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FASTRAK Manual

1. eee 83 JUNE 2012 POLHEMUS INNOVATION IN MOTION F 76 81 FACTOR secot n nnriocitre tiet bees 76 81 factory defaults 5 niece tee 79 Factory Defaults ienen nseni C 3 FASTRAK Commands Index ee FASTRAK Data Record FASTRAK GUI een reef epe FCC Statement ii ldslitio P S Figure Black Box System sss D 3 Complete FASTRAK System 1 Completing the Found New Hardware Wizard 30 Connection of USB Cable to Switch to USB Mode 28 29 DC Power Cable Installation cccecseeeeeeseeeees 3 4 Default I O Select Dip Switch Settings 17 Driver Files Search Results FASTRAK SEU Front View iu FASTRAK SEU Rear View eee 15 Hardsware Irst ll eet ttt tenen Hemisphere Vector is Install Hardware Device Divers 30 Locate Driver Files itr re 30 Mounting Transmitter and Receiver on 2x4 2 Position amp Orientation Measurement System Diagram Power Connector eerte eorr tenebre vaste t E eae Rea ee INTOSR SCENES UI Receiver Connection Receiver Dimensions in Inches 22 RS 232 Cable Connection eese 19 Transmitter Dimensions In Inches 21 USB communication with FASTRAK established 30 USB communications with FASTRAK established 31 frequency reference numbers Frequency Se
2. If the FASTRAK system is already powered up and connected to the computer the PiMgr will discover the connection immediately upon startup If not you will need to manually create the connection once you have powered up FASTRAK To do this first you must select the type of connection you wish to create If you want to create a USB connection skip to Step 9 PiMer defaults to a USB connection If you want to create an RS 232 connection first configure the serial port settings by opening the Device Configuration dialog Open this dialog off the Device menu Device gt Device Configuration and select the Connection tab Select the RS 232 Connection Type on the left and the appropriate RS 232 Properties on the right Then select OK 5 JUNE 2012 POLHEMUS INNOVATION IN MOTION FASTRAK MANUAL Traces Connie irs io Source Mounting Frame Active Sensors General Connection Filters Connection Type RS 232 Properties 1 Com Port rame RS 232 C USB Baud Rate 115 200 v Parity None Cancel Apply Figure 1 9 RS 232 Configuration Settings d To create a connection select the Connect button on the PiMegr toolbar sl When the connection has been established the connection icon at the lower right will change to e To collect a single frame of motion data from the FASTRAK system select the Single button on the toolbar f You can also do this by typing p or P anywhere on
3. Resume Data Transmission page 86 is issued 87 JUNE 2012 POLHEMUS INNOVATION IN MoTION FASTRAK MANUAL AY Reinitialize System Syntax Purpose Relatives Default Example Rev G Y Reinitializes the entire system to the power up state The user should allow sufficient time for the system to run through its self test and initialization wait for the green light to stop flashing before attempting to send the system additional commands K W X N A If the user wanted to set the system EEPROM back to its original factory default condition the following commands should be sent 1 W 2 K 3 Y The system will now be in its original factory default condition The Y simulates turning the system power off then back on again to allow user to verify the AK Save Operational Configuration command page 85 worked properly 88 JUNE 2012 POLHEMUS INNOVATION IN MoTION FASTRAK MANUAL 10 Command Error Command errors are defined as follows COMMAND ERROR RECORD IDENTIFIER INITIATING COMMAND all invalid commands byte s Identification Format jm Record Type 2 Al ds Blank Al 3 Sub record type E Al 4 10 ERROR 11 Erroneous command as it was input 11 ERROR EC IT V Error code from following list 1 Required field missing 2 Required numeric is non numeric 3 Value is outside required range
4. V 4is KM r Equation D 1 Coupled through the Magnetic Linkage is a noise quantity Ni which is composed of incidental link noise plus atmospheric noise Additionally system noise generated as a function of the black box electronics is given by Ny System noise Np is the sum of quantization shot and thermal noise and is referred to the input of the black box These noise quantities are algebraically added to the voltage equation for the input to the black box and expressed as V lgKM N amp N r Equation D 2 SIGNAL TO NOISE S N RATIO At the output of the black box the signal S portion of the S N ratio is the value of any given position and orientation of the receiver It could be considered as the input equation stated above minus the noise components times the transfer function of the black box The noise portion N is the noise components of the input equation times the black box transfer function and is observed as the deviation in the output parameters about the given position and Rev G D 3 JUNE 2012 POLHEMUS INNOVATION IN MoTION FASTRAK MANUAL orientation Therefore determining the S N ratio from a black box perspective involves the use of a precise mechanical positioning instrument with a precision gimbal Using surveyed precisely known attitude coordinates azimuth elevation and roll a statistically valid number of measurement samples are taken at each attitude For each attitude the mean vector su
5. X Configuration Control Data Syntax X string Or X lt gt to retrieve the current configuration control data Definition Configuration control data is user specified information that is stored in the status record The status record is retrieved with the S System Status Record command page 68 This gives the user the ability to identify a particular FASTRAK system in the status record Purpose A maximum of 32 ASCII characters may be entered as configuration control data in EEPROM with this command The K Save Operational Configuration command page 85 must be used to save the new configuration control data in the FASTRAK EEPROM The specific parameters are string a maximum of 32 ASCII characters can be used to identify the configuration control data Relatives K AN W Default The default configuration control data retrieved with the X command is as follows OutputCompensat CPG2030 003 10 This is a Polhemus configuration code Example A user could enter project specific information with the X command as follows XF18 Simulator05 Saint Louis lt gt Sending the S command to the system would yield the following result 21S3F0 0 103 00F18 Simulator05 Saint Louis NOTE Resetting the EEPROM with the Wi Reset System to Defaults command page 79 alters the contents of this data area to OutputCompensat CPG2030 003 10 RECORD IDENTIFIER X INITIA
6. 4 Specified frequency not hardware configured 5 Internal buffer limits exceeded 99 Undefined input cannot identify command 3 s PS position TESTE e Character position in the input record note numbering starts 0 1 2 22 643 FL field SE ws Field number causing the error note numbering of the field is 0 1 2 and starts at 0 following the command identifier 29 3 ST station Number of the affected system station less 1 i e this value ranges from 0 3 stations are numbered in commands as 1 4 Rev G 89 JUNE 2012 POLHEMUS INNOVATION IN MoTION FASTRAK MANUAL 11 Default Operation with a Stylus The stylus may be used as a receiver in any of the receiver ports However the button on the stylus will only work when the stylus is connected to Station 1 The stylus functions as a receiver with the electrical center offset from the tip of the stylus via software Operation of the switch on the Stylus will cause the following actions as a function of the various FASTRAK commands and modes No other actions are possible In NON continuous output mode pressing the switch defines to the FASTRAK system a P command When a C Continuous Output Mode command see page 41 is entered via RS 232 or USB to enable continuous mode the system immediately responds with output as defined in the manual however when the Stylus switch is pressed output is interrupted but this
7. Items 5 6 and 7 or 55 56 and 57 may be obtained to construct the line of sight line of hear and line of plumb vectors as follows Three 3 values are obtained from each item above Item 5 or 55 5a 5b 5c 55a 55b 55c Item 6 or 56 6a 6b 6c 56a 56b 56c Item 7 or 57 217a 7b 7c 57a 57b 57c Then the a column above is the line of sight vector the b column above is the line of hear vector and the c column above is the line of plumb vector Rev G 60 JUNE 2012 POLHEMUS INNOVATION IN MoTION FASTRAK MANUAL System Data Record IEEE Floating Point Format RECORD IDENTIFIER none INITIATING COMMANDS P or in continuous mode byte s Identification Format 5s Record type 0 Al p Station Number Al 3 i System error code Al See Note 2 on previous page TE ass ASCII space character Al TELS Carriage return line feed jm x y z position Cartesian coordinates 3 SingleFP jm az el roll Euler orientation angles 3 SingleFP JP uus X direction cosines of the receiver s x y z axes 3 SingleFP See Note 1 T ss Y direction cosines of the receiver s x y z axes 3 SingleFP See Note 1 y m Z direction cosines of the receiver s x y z axes 3 SingleFP See Note 1 a The system data record contents are specified by the user using the O Output Data List command page 57 and may vary from configuration to configuration Therefore the specific location of a data
8. The Frequency Select Modules are color coded for carrier frequency identification as described in Carrier Frequency page 13 IMPORTANT NOTE As with any handling of an electronics printed circuit board PCB when inserting other frequency select modules to change the carrier frequency static electricity precautions must be observed Do not remove and replace frequency select modules with power applied to the SEU Also do not handle or touch the main PCB without first being grounded at an ESD safe workstation 7 8 RS 232 I O The RS 232 I O serial connector is a standard 9 pin male D type connector located on the rear panel of the SEU as shown in Figure 7 2 on page 15 The pinout identification for this connector is as follows FASTRAK End User End Not used RxD Receive Data TxD Transmit Data to the FASTRAK TxD Transmit Data RxD Receive Data from the FASTRAK Not used Not used Not used Not used Not used VD G A CL P AHA ra Z 4 4 CQ 4 4 Z Q Z J Rev G 18 JUNE 2012 POLHEMUS INNOVATION IN MoTION FASTRAK MANUAL Figure 7 5 RS 232 Cable Connection NOTE Many commercially available cables do not include connections for all pins so do not assume that these connections are made Please refer to APPENDIX F Cable Diagrams on page F 1 to find the specific interconnection scheme for your host computer in order to obtain a
9. determination by Polhemus that the parts or Products are defective and covered by the warranty set forth above Polhemus at its option shall repair or replace the same without cost to Buyer Buyer shall be responsible for any import export duties tariffs and pay all charges for transportation and delivery costs to Polhemus s factory for defective parts where directed to be sent to Polhemus and Polhemus shall pay for transportation costs to Buyer s facility only for watranty replacement parts and Products Removed parts covered by claims under this warranty shall become the property of Polhemus In the event that allegedly defective parts are found not to be defective or not covered by warranty Buyer agrees that Polhemus may invoice Buyer for all reasonable expenses incurred in inspecting testing repairing and returning the Products and that Buyer will pay such costs on being invoiced therefor Buyer shall bear the risk of loss or damage during transit in all cases Any repaired or replaced part or Product shall be warranted for the remaining period of the original warranty or thirty 30 days whichever is longer Warranties shall not apply to any Products which have been e repaired or altered other than by Polhemus except when so authorized in writing by Polhemus or e used in an unauthorized or improper manner or without following normal operating procedures or e improperly maintained and where such activities in Polhemus s sole
10. lt FHIGH lt 1 a scalar value that specifies the maximum allowable transition rate from minimum filtering for highly dynamic input conditions to maximum filtering for relatively static input conditions by proportionately limiting the decay to the low filter limit whenever the input conditions effect a transition to a narrower bandwidth Allowable range of values 0 lt FACTOR lt 1 When the form of the command is x 1 lt gt the position filter is disabled This is the system default configuration n Macro filter is enabled when n gt 2 as defined below Note this also sets the macro filter setting for attitude See v command n 2 No Filter This macro has the same effect as x 1 lt gt above n 3 Low Filter n 4 Medium Filter n 5 Heavy Filter 81 JUNE 2012 POLHEMUS INNOVATION IN MoTION FASTRAK MANUAL Example Relatives Default Example To select medium filtering type x4 lt gt The filter is a single pole low pass type with an adaptive pole location i e a floating filter parameter variable The pole location is constrained within the boundary values FLOW and FHIGH but is continuously self adaptive between these limits as a function of the sensitivity parameter F and the sensed ambient noise plus translational rate input conditions For input rate conditions that fall within the adaptive range the adaptive feature varies the pole location between the FLOW and FHIGH limits so as t
11. reliable serial interface If you do not find your particular host s RS 232 I O interconnection scheme in APPENDIX F Cable Diagrams on page F 1 refer to Contacting Polhemus Customer Service on page 8 and FAX a copy of your host computer s pin out identification from its user s manual Polhemus will respond with advice on how to make the serial connection between your FASTRAK and your host computer NOTE THE FASTRAK SYSTEM BEHAVES AS A TRANSMITTER ON THE RS 232 AND THEREFORE A NULL MODEM CABLE IS REQUIRED 7 9 USB I O The USB I O connector is a standard Series B connector located on the rear panel of the FASTRAK SEU as shown in Figure 7 2 on page 15 The connector on the FASTRAK is a square shaped connector with two corners shaved off for correct orientation upon insertion The connector on the host PC is a Series A connector and is rectangular shaped Since the connectors on each end of the USB cable are different it is impossible to connect the cable incorrectly The signals on the FASTRAK USB connector conform to the USB standard The USB communication cable used to connect the FASTRAK to the host computer is a standard cable that is commercially available 7 10 Optional RS 422 I O The optional RS 422 connector is identical to the RS 232 connector in form fit function and location on the rear of the SEU IMPORTANT NOTE In order to use this interface the FASTRAK system must be ordered from the factory configured for RS 422 c
12. the brick s DIN connector into the power input connector on the rear panel of the electronics unit and firmly seat Figure 1 6 DC Power Cable Installation Identify the power ON OFF rocker switch located on the rear panel of the electronics unit Ensure this switch is in the OFF position logic 0 DOWN before inserting the brick s convenience plug into the 110 220 VAC outlet 6 Connect the USB cable to the FASTRAK as shown below and the remaining end of the cable into a USB port on the host computer Rev G 3 JUNE 2012 POLHEMUS INNOVATION IN MoTION FASTRAK MANUAL Figure 1 7 DC USB Cable Installation 7 Install the Host Software NOTE FASTRAK Host Software is intended to be installed on a computer running Windows XP Vista Win 7 only Insert the FASTRAK Host Software CD ROM into your computer s CD ROM drive If the FASTRAK Host Software Installation Panel does not run automatically then navigate to the CD ROM drive using Windows Explorer Run Setup exe The Host Software Installation Panel will appear Select Install Host Software The installation wizard will walk you through the installation For simplicity it is recommended that you use the default installation settings suggested by the installation wizard When the installation is complete if you are planning to use your computer s USB port to connect to the FASTRAK System leave the CD ROM in the drive It will be needed w
13. 15 Video sync is available to minimize noise generated by computer monitors detected by the receivers In order to use the video sync capability the Video Sync Detector cable must be connected to the video sync input connector on the FASTRAK The detector can then be positioned on the monitor surface where it will detect a sync pulse After sending the y2 external sync command to the FASTRAK it will be synced to the monitor See Synchronization on page 31 for more information on synchronization 7 12 Power Input Receptacle The Power Input is a 5 contact female shielded DIN type receptacle located on the rear panel of the SEU as shown in Figure 7 2 on page 15 Pin outs for this receptacle are as follows Pin Function 1 GROUND Digital 2 GROUND Analog 3 5 VDC 4 15 VDC 5 15 VDC NOTE Digital ground pin 1 is not electrically shorted to analog ground Pin 2 on the PCB They are electrically connected in the power supply 7 13 Transmitter The Transmitter is the device which produces the electro magnetic field and is the reference for the position and orientation measurements of the receivers It is usually mounted in a fixed Rev G 20 JUNE 2012 POLHEMUS FASTRAK MANUAL INNOVATION IN MOTION position to a non metallic surface or stand which is located in close proximity to the receivers The Transmitter is dimensionally shown in Figure 7 6 including the position of the electrical center There are four 4 20 NC t
14. 2004 Voltage Dips amp Interruptions Rev G ii JUNE 2012 POLHEMUS INNOVATION IN MoTION FASTRAK MANUAL Table of Contents LIST OF FIGURES sesssscssescsscsascccsscsssesntsedscsssonssaansssocssnecossecssanccsenscosssssvantsestesteossnsceseedssenscesnecoassdeessscoussseesss V 1 GETTING STARTED Pcr 1 2 CONTACTING POLHEMUS CUSTOMER SERY ICE ecce eese eren eene ette seen seen eo seen seen 8 3 CURRENT FASTRAK VS PREVIOUS VERSIONS 4 eere eee ee ee eene ete seen oeste seen sette seen seen 9 4 FASTRAK COMMANDS INDEX sssisscc sccssiscsctsaccossteseeacsasesseceseecessccssstsvesnssacecsedesevesseasestacesenesseass 10 5 IPECHINICAT OOVERY EW E 11 6 SPECIFICATION P M 12 Position ET 12 Anpular COVeTQBe susci gantep ies TERIS GU IIT UE tO UN RUD IU qe ate 12 GEES 12 Resolution WS RONG Coes sess sas one RO DRIHEHHU RUM US GI HI EA tines 12 Mor E REEE 12 Output 12 Update R te eats ani ott on IR HERE RR DUI Ep e E estt tt 12 G7 0112 27174 1 RE 13 Eege 13 AELIAN E 13 Operating Environments 13 SAHNE MIHI 13 Physical Characteristics eese ee sees eee eene aN Ee A ENE ER EE EEEE EE ETAn eE 13 ee 14 7 COMPONENT DESCRIPTION 55 i eicseonscen e pPe epa Se eS RCHEREE NES eNSS eL PENNE EUR E QURE SER
15. Q INITIATING COMMAND Q Rev G 64 JUNE 2012 POLHEMUS INNOVATION IN MOTION FASTRAK MANUAL byte s Identification Format Dos Record type 2 Al 2 us Station number AI c Sub record type Q Al 4 12 Maximum azimuth value Sxxx xxxb 13 21 Maximum elevation value Sxxx xxxb 22 30 Maximum roll value Sxxx xxxb 31 39 Minimum azimuth value Sxxx xxxb 40 48 Minimum elevation value Sxxx xxxb 49 57 Minimum roll value Sxxx xxxb 58 59 Carriage return line feed Rev G 65 JUNE 2012 POLHEMUS INNOVATION IN MoTION FASTRAK MANUAL R Reset Alignment Reference Frame Syntax Rstation lt gt Purpose This command resets the alignment reference frame for the specified station to the station reference frame It provides an easy way to re align the reference frame to the factory default values The command parameter is defined as station the number of the station to be reset Relatives A Example Any time the alignment command A1 is used it is best to send the reset alignment command R1 lt gt first That way there is no risk of building one alignment on top of another See A Alignment Reference Frame on page 37 for the Standard Alignment Procedure Rev G 66 JUNE 2012 POLHEMUS INNOVATION IN MoTION FASTRAK MANUAL r Transmitter Mounting Frame Syntax rstation A E R lt gt or rstation lt gt to read back the current transmitter moun
16. Rev G 52 JUNE 2012 POLHEMUS INNOVATION IN MoTION FASTRAK MANUAL T Define Increment Syntax Purpose Relatives Default Example Istation distance lt gt or Istation lt gt to read back the current increment selection This command allows the user to control when data records will be sent to the host based on receiver movement The distance selection allows the user to specify exactly how much movement will be required before data is produced If the user enters Istation lt gt the system outputs the current distance value selection NOTE The system should be in continuous output mode in order for this command to work properly Definitions of the command parameters are listed below station the number of the station whose increment is to be changed distance the minimum distance a receiver must move before a data record is output to the host computer The units of measure inches or centimeters for the distance value must be consistent with the current selection of system units None The default value is 0 0 inches which disables the increment feature If the user wants the system to output data each time the receiver on station 1 moves 2 in any axis the following command should be entered NR C The system will now output a data record each time station 1 receiver moves 2 in any axis RECORD IDENTIFIER I INITIATING COMMAND I Rev G byte s Identi
17. Where applicable examples of the command in use will be given All commands are input on the RS 232 serial port and consist of ASCII characters Additionally format notations and conventions for commands and outputs are presented first 9 1 Command Format Notation and Convention Use the following format notation to enter commands Items shown inside square brackets are optional To include optional items type only the information inside the brackets Do not type the brackets lt gt Represents an ASCII carriage return or enter Whenever shown this value must be present to terminate the command sequence An ellipsis indicates that you can repeat an item A comma represents a delimiter in a list of optional parameters The comma must be present for those parameters which are omitted except for the case of trailing commas For example Qs p1 p4 lt gt is the proper command format when omitting parameters p2 and p3 Commas following the parameter p4 are not required if parameters p5 and p6 are omitted A vertical bar means either or Choose one of the separated items and type it as part of the command For example ONIOFF indicates that you should enter either ON or OFF but not both Do not enter the vertical bar n Represents the Ctrl key Rev G 34 JUNE 2012 POLHEMUS INNOVATION IN MoTION FASTRAK MANUAL 9 2 Command Format Notes e All commands and alphabetic parameters are case sensitive They must
18. and orientation the six pieces of data needed to fully describe tracking of an object in 3D space Some tracking devices by C 5 JUNE 2012 POLHEMUS INNOVATION IN MoTION FASTRAK MANUAL Pitch Quaternion Receiver Roll Sensor Station Stylus Sync Rev G virtue of their principle of operation can produce only position or only orientation whereas others can produce both P amp O although the user usually can opt for only those parameters desired Same as elevation A four parameter quantity representing a vector and a scalar The quaternion q qo i q j q2 k qs can be used to represent the receiver s orientation without the need for trigonometric functions The attitude matrix output from the 3SPACE can be equivalently represented by the following matrix using quaternions X Directional Cosines Y Directional Cosines Z Directional Cosines d 4 44 704927 109s 2445 4042 2 4340 4 92 h t 2 424 4041 2 4193 4042 2 4199 9392 4 4 d q The receiver measures the low frequency magnetic field generated by the transmitter The receiver is used to track both the position and orientation of the object to which it is attached relative to the measurement reference frame Coordinate of orientation tracking about the azimuth elevation axis where an increase of the angle is clockwise as viewed from behind or in the same direction as the object is facing Same as Receiver The transmitter rec
19. be entered in upper or lower case as defined in the syntax e Any command with a next to it means that it cannot be stored in EEPROM i e if a K Save Operational Configuration command see page 85 is executed the information will not be saved after the system power is turned off e For those commands involving an optional list of parameters if some of the parameter values are omitted the current system retained value of that parameter is used in its place e The RELATIVES field contains a list of those commands which provide related information to the system For example the b Unboresight command page 40 is a relative to the B Boresight command page 39 e The term station is a transmitter receiver pair The four receivers paired with the one available transmitter are assigned station numbers one through four 1 4 e FASTRAKs are shipped configured in one of four 4 possible frequencies The frequencies are referenced as follows Ref Number Frequency 1 8013 Hz 2 10016 Hz 3 12019 Hz Standard 4 14022 Hz e A numeric floating point value will be accepted by the FASTRAK if any of the following formats are used FOR EXAMPLE 3 0 may be specified as 3 3 3 0 or 3 0 E 00 See each command s format for generally accepted accuracy range e The notation R Sxx xxxB represents the ASCII output format for the specific data element where R isthe repeat count and what follows in parenthesis is repea
20. during periods of highly dynamic input conditions Allowable range of values FLOW lt FHIGH lt 1 a scalar value that specifies the maximum allowable transition rate from minimum filtering for highly dynamic input conditions to maximum filtering for relatively static input conditions by proportionately limiting the decay to the low filter limit whenever the input conditions effect a transition to a narrower bandwidth Allowable range of values 0 lt FACTOR lt 1 When the form of the command is v 1 lt gt the attitude filter is disabled This is the system default configuration 76 JUNE 2012 POLHEMUS INNOVATION IN MoTION FASTRAK MANUAL Example Relatives Default Example Rev G n Macro filter is enabled when n gt 2 as defined below Note this also sets the macro filter setting for position See x command n 2 No Filter This macro has the same effect as v 1 lt gt above n 3 Low Filter n 4 Medium Filter n 5 Heavy Filter To select medium filtering type v4 lt gt The filter is a single pole low pass type with an adaptive pole location 1 e a floating filter parameter variable The pole location is constrained within the boundary values FLOW and FHIGH but is continuously self adaptive between these limits as a function of the sensitivity parameter F and the sensed ambient noise plus rotational rate input conditions For input rate conditions that fall within the adaptive rang
21. elevation and roll data output to be 0 15 0 respectively SUB RECORD IDENTIFIER G INITIATING COMMAND G Rev G byte s Identification Format l Record type 2 Al 2 Station Number Al ds Sub record type G Al 4 10 Azimuth reference angle SXXX XX 11 17 Elevation reference angle SXXX XX 18 24 Roll reference angle SXXX XX 25 26 Carriage return line feed 49 JUNE 2012 POLHEMUS INNOVATION IN MoTION FASTRAK MANUAL H Hemisphere of Operation Syntax Description Purpose Rev G Hstation p1 p2 p3 lt gt or Hstation lt gt to read back the current hemisphere selection Because of the symmetry of the magnetic fields generated by the transmitter there are two mathematical solutions to each set of receiver data processed Therefore only half of the total spatial sphere surrounding the transmitter is practically used at any one time without experiencing an ambiguity usually sign flips in the X Y Z measurements This half sphere is referred to as the current hemisphere The chosen hemisphere is defined by an LOS line of sight vector from the transmitter through a point at the zenith of the hemisphere and is specified by the LOS direction cosines Since the receiver s can only operate in one hemisphere at a time relative to the transmitter it is necessary to tell the FASTRAK system which side of the transmitter they will be on for each station A hemisphe
22. elevation and roll are designated v 0 and in Figure C 1 These angles represent an azimuth primary sequence of frame rotations that define the current orientation of the receiver with respect to its zero orientation state The defining rotation sequence is an azimuth rotation followed by an elevation rotation followed by a roll rotation The azimuth angle y is defined in Figure C 1 as a rotation of the X and Y reference axes about the Z reference axis Note that the transition axes labeled X and Y represent the orientation of the X and Y axes after the azimuth rotation The elevation angle 0 is defined as a rotation of the Z reference axis and the X transition axis about the Y transition axis Note that the transition axis labeled Z represents the orientation of the Z reference axis after the elevation rotation Note also that the current x axis of the current receiver frame represents the orientation of the X transition axis after the elevation rotation Lastly the roll angle is defined as a rotation of the Y and Z transition axes about the x axis of the receiver frame Note that the y and z axes of the current receiver frame represent the orientation of the Y and Z transition axes after the roll rotation Note also that in the example of Figure C 1 the azimuth elevation and roll rotations are positive negative and positive respectively A list of the data items included in a data record Acronym for position
23. gol eM dees RRS 67 Systems Electronics Unit SEU en 11 Rev G JUNE 2012 POLHEMUS INNOVATION IN MOTION T Table of Contents Technical Overview theory of operaton tip 56 Dni M 56 Tracker Alignmenit etr trt inet C 7 Tracker Calibration oinnes ei C 7 Tracker Latency Tracker Response 5 entretenir C 7 trademarks eise deeg eegen Ee ii translational resolution Translational Resolution transmitter eee e RE E Transmitter Input Transmitter Mounting Frame m Transmitter POrt 5 ionem eet trouble shooting eese TTL compatible tr i imr s dreet GE 40 Units Update R te route robe ct eee VSB niei eir iiec USB communication establishing USB c USB Interfacecoseod utente ono Ade m USBmode s uero ote te tet elitas Rev G FASTRAK MANUAL USB Op ration icri ENEE EES 28 Useful Range s C 7 User Defaults User s application software 30 Using the USB Interface 28 verify COMMUNICATION 0 0 eeeee eee eeeeeeeeeeeeeeeeeeaeeeeeeeeees 68 Video Sync Video Sync Detector Video Sync Input is Video Sync Mode eie iter eterne KCL E A 1 Windows 2000 NEE 29 Windows XD 29 JUNE 2012
24. in the default hemisphere forward the following procedure should be used to enable hemisphere tracking on station 1 1 Position the receiver on the positive X side of the transmitter the side opposite from where the cable comes out of the transmitter shell and turn the system on 2 While the receiver is located in the forward hemisphere send the hemisphere tracking command to the FASTRAK The command should be H1 0 0 0 lt gt 3 The receiver can now be moved to any side of the transmitter without worrying about hemisphere selection 4 Do not save this configuration to the system EEPROM using the R command because it will save whatever the current computed hemisphere selection happens to be for that position of the receiver relative to the transmitter 5 If necessary the user can disable the hemisphere tracking feature by sending a 51 JUNE 2012 POLHEMUS INNOVATION IN MoTION FASTRAK MANUAL normal hemisphere selection e g H1 1 0 0 lt gt to go back to the forward hemisphere selection TRANSMITTER Figure 9 2 Hemisphere Vector Zenith represents the hemisphere vector RECORD IDENTIFIER H INITIATING COMMAND H byte s Identification Format l Record type 2 Al P Station number Al Saach Sub record type H Al 4 10 Vector x component SXX XXX LISTA Vector y component SXX XXX 18 24 Vector z component SXX XXX 25 26 Carriage return line feed
25. is meaningful only to factory personnel The T command is useful to attempt to clear a problem however if an error re occurs and after you have verified your setup configuration consultation with the factory is recommended The parameters are BITnumber The BIT number for which added information is requested see below O This parameter if used is specified as a 0 zero If present the BITnumber specified is reset cleared Relatives S Default N A Example BIT number Code Transmitter amp Receiver Error Codes 65 A X Driver Linearity 66 B Y Driver Linearity 67 C Z Driver Linearity 68 D x Gain Linearity 69 E y Gain Linearity 70 F z Gain Linearity 71 G X Slope of Driver X Linearity Line 72 H Y Slope of Driver Y Linearity Line 73 I Z Slope of Driver Z Linearity Line 74 J X Slope of Coil Receiver X Linearity 75 K Y Slope of Coil Receiver Y Linearity 76 L Z Slope of Coil Receiver Z Linearity 77 83 Not Used Reserved for future use 84 T Receiver PROM Error 85 U Transmitter PROM Error 86 V Receiver PROM Circuit Error 87 W Transmitter PROM Circuit Error 88 X Driver Characterization Validity 89 Y Receiver Characterization Validity 90 Z Receiver Coil Validity Rev G 70 JUNE 2012 POLHEMUS INNOVATION IN MOTION FASTRAK MANUAL BIT number Code Self Calibration Error Codes 97 a X Driver Limits Self Calibration 98 b Y Driver Limits Self Calibration 99 c Z Driver Limits Self C
26. item in the output record is not determined until the record contents are defined Rev G 61 JUNE 2012 POLHEMUS INNOVATION IN MoTION FASTRAK MANUAL o Set Output Port Syntax Description Purpose Relatives Default Example Rev G orate parity bits HHS lt gt The system output port settings including RS 232 BAUD rate parity and number of bits per character may be established to specified values Sets the output BAUD rate for RS 232 port to a specified rate The parameters are rate is specified as follows 24 2 400 48 4 800 96 9 600 192 19 200 384 38 400 576 57 600 1152 115 200 parity N none O Odd E even bits Tors Note 1 The number of stop bits is always one 1 Note 2 For seven 7 bits parity may be NONE ODD or EVEN For eight 8 bits there is never a parity bit i e NONE Note 3 8 data bits are required when using either the standard binary format or the 16 BIT format None Based on I O switch settings Suppose there is a requirement to change the baud rate in software to 19 200 baud while the rate set by the I O select switches is 115 2K baud It can be accomplished with the following command without turning off and restarting the system 0192 N 8 0 lt gt The system serial communication parameters will now be 19200 baud no parity 8 data bits and 1 stop bit NOTE The communication software will now have to be re set to the new ba
27. judgment have adversely affected the Products Neither shall warranties apply in the case of damage through accidents or acts of nature such as flood earthquake lightning tornado typhoon power surge s or failure s environmental extremes or other external causes Warranties shall not apply to any Products if the Products are defective because of normal wear and tear or e used for any purpose without obtaining any applicable regulatory approvals Rev G A 1 JUNE 2012 POLHEMUS INNOVATION IN MoTION FASTRAK MANUAL POLHEMUS DOES NOT WARRANT AND SPECIFICALLY DISCLAIMS THE WARRANTY OF MERCHANTABILITY OF THE PRODUCTS OR THE WARRANTY OF FITNESS OF THE PRODUCTS FOR ANY PARTICULAR PURPOSE POLHEMUS MAKES NO WARRANTIES EXPRESS OR IMPLIED EXCEPT OF TITLE AND AGAINST PATENT INFRINGEMENT OTHER THAN THOSE SPECIFICALLY SET FORTH HEREIN IN NO EVENT SHALL POLHEMUS BE LIABLE UNDER ANY CIRCUMSTANCES FOR SPECIAL INCIDENTAL OR CONSEQUENTIAL DAMAGES INCLUDING BUT NOT LIMITED TO LOSS OF PROFITS OR REVENUE WITHOUT LIMITING THE FOREGOING POLHEMUS S MAXIMUM LIABILITY FOR DAMAGES FOR ANY CAUSE WHATSOEVER EXCLUSIVE OF CLAIMS FOR PATENT INFRINGEMENT AND REGARDLESS OF THE FORM OF THE ACTION INCLUDING BUT NOT LIMITED TO CONTRACT NEGLIGENCE OR STRICT LIABILITY SHALL BE LIMITED TO BUYER S ACTUAL DIRECT DAMAGES NOT TO EXCEED THE PRICE OF THE GOODS UPON WHICH SUCH LIABILITY IS BASED The Products are not certified for medical or bio medical use Any
28. press P once 6 The system then composes the alignment coordinates and prints the new alignment parameters to the screen SUB RECORD IDENTIFIER A INITIATING COMMAND A byte s Identification Format 1 Record type 2 Al 2 Station Number Al 3 Sub record type A Al 4 24 Origin coordinates 3 Sxxx xx 25 45 Positive X axis coordinates 3 Sxxx xx 46 66 Positive Y axis coordinates 3 Sxxx xx 67 68 Carriage return line feed Rev G 38 JUNE 2012 POLHEMUS INNOVATION IN MoTION FASTRAK MANUAL B Boresight Syntax Purpose Relatives Default Example Rev G Bstation lt gt This command causes the tracking receiver to be electronically aligned in orientation with the user system coordinates This results in azimuth elevation and roll outputs equal to the boresight reference values usually 0 0 0 which is the system default at the current orientation The tracker then produces outputs relative to this reference Any receiver orientation can be designated as the zero orientation point The command parameter is defined as station the number of the station to be boresighted b G The zero orientation condition occurs when the receiver orientation corresponds to the transmitter orientation The receiver may be mounted on a person s head to measure where it is pointing When the subject s head is looking at a given object the user may want the system angular outputs to be zer
29. return address is Polhemus 40 Hercules Drive Colchester VT 05446 Attention RMA __ Telephone From the U S and Canada 800 357 4777 Telephone From outside the U S and Canada 802 655 3159 Fax 802 655 1439 Rev G 8 JUNE 2012 POLHEMUS INNOVATION IN MoTION FASTRAK MANUAL 3 Current FASTRAK vs Previous Versions Congratulations on purchasing our FASTRAK system For our customers who presently own one or more of our tracker products there are some minor differences which should be noted for all FASTRAKs produced as of January 2012 e Fan has been removed e 16 bit binary has been removed e Master Slave mode has been removed e External sync output has been removed Rev G 9 JUNE 2012 POLHEMUS INNOVATION IN MOTION 4 FASTRAK Commands Index Cmnd Ltr KEE Je El t DA DIE en D I DO e HI om CG Die por D e iad Rev G FASTRAK Command Title Alignment Reference Frame Boresight Unboresight Continuous Output Mode Disable Continuous Output Enable Fixed Metal Compensation Disable Fixed Metal Compensation Define Stylus Button Function Enable ASCII Output Format Enable Binary Output Format Boresight Reference Angles Hemisphere of Operation Define Increment Active Station State Define Tip Offsets Output Data List Set Output Port Single Data Record Output Angular Operational Envelope Reset Alignment Reference Frame Transmitter Mounting Frame System Status Record Built In Test Info
30. the tracker s cycle Rev G E 2 JUNE 2012 POLHEMUS INNOVATION IN MoTION FASTRAK MANUAL FILTER RESPONSE LAG FASTRAK has optional filters that are intended to smooth the receiver s calculated position and orientation in mechanically or magnetically noisy environments The degree of filtering is user selectable from very heavy to none at all or the degree of filtering can be automatically selected in real time by the tracker as it adapts to noise Filtering can introduce lag in response the sync to output latent period remains unchanged recall that latent period is defined as a first indication and not a final settled response but the data that is output may not correspond to where the receiver was recently To help understand the response of the optional filters the filter algorithm is described and analyzed in the following paragraphs FASTRAK coordinate filters are exponential filters as described by the following equation lt xX gt ax4 1l a lt x gt Equation E 1 ee 2 In this equation x is the unsmoothed receiver coordinate measured at time k it may be a coordinate of position or orientation The variable lt x gt is the filter output at discrete time k and lt x gt is the smoothed value at time k 1 The filter parameter a controls the degree of filtering and must be within the range 0 lt a lt 1 Small values of a produce heavy filtering large value
31. x Oorl 3 Sx xxxxxESxxb 3 Sx xxxxxESxxb 3 Sx xxxxxESxxb 3 Sx xxxxxESxxb 3 Sx xxxxxESxxb 4 Sx xxxxxESxxb x where x Oorl The system data record contents are specified by the user using the O command and may vary from configuration to configuration Therefore the specific location of a data item in the output record is not determined until the record contents are defined Rev G 59 JUNE 2012 POLHEMUS INNOVATION IN MoTION FASTRAK MANUAL Note 1 Original precision is retained for compatibility with previous Polhemus 3SPACE systems Also note that some item values are repeated as extended precision items although no output difference is made 1 e space cr If Original and extended precision may be freely mixed in an output record but it is recommended that extended precision be used if compatibility is not required as the original precision may be deleted in future systems Note 2 This code will in general output the last error that the system BIT Built In Test routines found prior to the output of this system data record If any BIT clearing has been commanded see the T Built In Test Information command page 70 the system will search for an error that is currently set starting at the largest numeric error code value and then output the first error code found in the search that is set See T Built In Test Information page 70 for specified definitions of each error code Note 3
32. 0 0 40 0 60 0 800 100 0 120 0 Range inches Range Position Resolution Orientation Resolution inches inches degrees 12 0 0 00023 0 0026 24 0 0 0030 0 0147 36 0 0 019 0 0558 48 0 0 055 0 1266 72 0 0 346 0 369 120 0 1 605 2 960 Latency 4 0 milliseconds from center of receiver measurement period to beginning of transfer from output port Output Software selectable including extended precision Cartesian coordinates of position and Euler orientation angles are standard Direction cosines and quaternions are selectable English or metric units and ASCII or binary outputs also are selectable Update Rate One receiver 120 updates second Two receivers 60 updates second Rev G 12 JUNE 2012 POLHEMUS INNOVATION IN MOTION FASTRAK MANUAL Three receivers 40 updates second Four receivers 30 updates second Carrier Frequency The FASTRAK may be configured with any one of four discrete carrier frequencies to allow simultaneous operation of up to four systems in close proximity Carrier frequencies are selected via color coded Frequency Select Modules FSM These frequencies are Reference Frequency Color Code NNBWN ra 12019 Hz White TX1 A colored dot can be found on the FSM on the end closest to the connector and on the back panel of the FASTRAK SEU as it comes from the factory FSMs different from the standard can be specified by the user at time of order or can be purchased for a nominal fee at any ti
33. 1 identification 2 Data item 02 identification I2 Data item 03 identification D Data item n identification D Carriage return line feed 58 JUNE 2012 POLHEMUS INNOVATION IN MOTION System Data Record ASCII Format RECORD IDENTIFIER none INITIATING COMMANDS P or in continuous mode Item byte s Identification I Record type 0 2 Station Number S System Error Code See note 2 Original Precision O or 50 ASCII space character lor 51 Vm Carriage return line feed 2 J a x y z position Cartesian Coordinates 4 Deo az el roll Euler orientation angles 5 DF uu X direction cosines of the receiver s x y z axis See Note 3 6 PS Y direction cosines of the receiver s x y z axis See Note 3 7 TE Z direction cosine of the receiver s x y z axis D Note 3 11 LEN Orientation Quaternion Q0 Q3 16 JE Stylus Switch Extended precision 52 T x y z position Cartesian coordinates 54 Tta az el roll Euler orientation angles 55 Te X direction cosines of the receiver s x y z axis See Note 3 56 T Y direction cosines of the receiver s x y z axis See Note 3 57 Hom Z direction cosines of the receiver s x y z axis See Note 3 61 TEL Orientation Quaternion Q0 Q3 66 d Stylus Switch Factory use only 8 10 12 15 17 49 58 60 62 65 67 69 FASTRAK MANUAL Format AI AI AI Al 3 SXxx xx J Sxxx xx J3 Sx xxxx J Sx xxxx J Sx xxxx A Sx xxxx x where
34. AK MANUAL AQ Resume Data Transmission Syntax Purpose Relatives Default Example Rev G Q Resumes data transmission to the host device following suspension of transmission by a S command If a previous Q command has been issued without an intervening S this command will have no effect S N A If the FASTRAK system had been issued the C Continuous Output Mode command page 41 to output data continuously and then the 4S Suspend Data Transmission command page 68 had been used to suspend or temporarily stop the data transmission the following command could be used to start the data again Q The continuous data stream will now resume 86 JUNE 2012 POLHEMUS INNOVATION IN MoTION FASTRAK MANUAL AS Suspend Data Transmission Syntax Purpose Relatives Default Example Rev G S This command suspends data transmission to the host device until a subsequent AQ Resume Data Transmission page 86 is received If a previous S command has been issued without an intervening Q this command will have no effect Q N A If the FASTRAK system had been issued the C Continuous Output Mode command page 41 to output data continuously the following command could be used to suspend or temporarily stop the data transmission S The data stream will stop scrolling and will not begin again until a Q
35. Conn DIN 8 9 Pin Female Pin Identification Pin 1 8 2 3 Transmit Data Receive Data 2 4 Signal Ground 5 5 Receive Data Transmit Data 3 6 7 7 8 Rev G F 3 JUNE 2012 POLHEMUS INNOVATION IN MoTION FASTRAK MANUAL RS 232 Cable Diagram e SGI VTX Onyx Personal Iris To PC To FASTRAK Circular Connector D Type Conn DIN 8 9 Pin Female Pin Identification Pin 2 Transmit Data Receive Data 2 3 Receive Data Transmit Data 3 4 5 6 T Ground 5 8 7 9 8 Rev G F 4 JUNE 2012 POLHEMUS INNOVATION IN MOTION FASTRAK MANUAL INDEX Drei D 1 D 5 Accuracy and Resolution White Paper D 1 Active Station State suse Alignment alignment command Alignment Frame s esseeeeeee Alignment Reference Frame Angular Coverage territi rr toto reinen ns Angular Operational Envelope angular resolution eese APPENDIX A erit rr e ete risen APPENDIX B APPENDIX C APPENDIX E APPENDIX F ASCII Format Attitude Filt
36. Data Output field the message USB Communications with FASTRAK established should be displayed as shown below LISP Communications with Pau Teak ectabidhad Oats Dap aiziz De Des tpe Tea Is f eje Resint R ADI Se F Gemen C Dnay C breed TE logon Perg T Leg Fratand F Pesosa Se Log He e I r No Lag File Seite eter EEPROM Seve Lod Bebo os Rev G 30 JUNE 2012 POLHEMUS INNOVATION IN MoTION FASTRAK MANUAL Select the Request Data button to get data from the FASTRAK over the USB port IS EE Dus Das Type Onptay type Laa Pory f Seje Resint R Asa Tee wl D Fnatied F Feepes Does mmm Se Leni e oe Receiving data from the FASTRAK using the GUI confirms that the USB device drivers have been successfully installed on the host computer and the FASTRAK should now be able to communicate with the host application over the USB port For subsequent utilization of the USB I O simply make sure that the USB communication cable is connected to the FASTRAK and the host computer before turning on the FASTRAK power To return to RS 232 communication disconnect the USB cable and cycle the power on the FASTRAK system Make sure the RS 232 cable is connected and that the host communication software settings are set correctly i e com port selection baud rate parity etc 8 6 Synchronization Synchronization defines and controls the precise time that a FASTRAK system measureme
37. Direction Cosines Y Direction Cosines Z Direction Cosines CA SE CR QEX CA CE CA SE SR SA CR SA SR zk zk x E SA CE CA CR SA SE SR SA SE CR CA SR E x SE CE SR CE CR where CA Cos azimuth CE Cos elevation CR Cos roll SA Sin azimuth SE Sin elevation SR Sin roll Azimuth The coordinate of orientation tracking in the horizontal plane where an increase in the angle is clockwise when viewed from above Azimuth is a Rev G C 1 JUNE 2012 POLHEMUS INNOVATION IN MoTION FASTRAK MANUAL Baud Rate rotation around the Z or vertical axis The term yaw is often substituted for azimuth especially in the context of flight The signaling rate on a serial line For example to convey an 8 bit byte normally requires at least two additional bit times a start bit and a stop bit so that synchronization is possible without a separate clocking line For example such an arrangement implies for a 9600 baud rate conveyance of data at a 9600 8 10 7680 bit rate Benign Environment A tracking environment free of the need for special calibration or BIT Boresight bps Compensation Data Rev G compensation brought on by the unique features of a particular installation and its environment e g high light levels for optical tracking high sound levels for sonic tracking high metallic distortion for magnetic tracking If not otherwise noted all measurements and statements pertaining to tr
38. ERE EES 15 EARUM 15 7 2 TRANSMITTER PORT 15 7 3 AZOUiuidgucuulc p ENEE 16 TAPOWER INDICATOR SC CMC 16 Ted IO SHECTSWMOH C E 16 TO EXTERNA SYNG TO m m 17 7 7 FREQUENCY SELECT MODULE sese enne nnnsst ennt tern nnns sien entere dass sess enne te nass sees nean 18 PERS 2 lO EE 18 2 0 USB UO esent Eege 19 71 10 OPTIONAL RS 422 UO 19 TAD VIDEO SYNC U 20 7 12 POWER INPUT RECEPTACLE ear EES 20 ES EM TRANSMITTER TH 20 TVA RECEIVER S EE 22 Wel IBI CH 24 7 16 VIDEO SYNC DETECTOR EE 25 7 17 LONG RANGER TRANSMITTER 5 redeo ee a Seo EREE Eee RR EENS Evo vea ree die E E aI E ri 26 EE a TRANSMITTBR EET EE 26 7 19 SHORT RANGER TRGANSMITTER eene EAEE E stesse tana sse EREE ESEE ses eet sega assess enn 26 7 20 MINT RECEIVER 222055 035055005 O 26 8 SYSTEM OPERATION mST o Sni 27 SL TVO CONSIDERA TIONS 103 225035 50455558 ERC ee ER EEr EEEE RERE EEEE RES 27 DULL U 27 eT U 27 82 POWERING UP FASTRAK iint serere trie eres E sbedeeseebadarase
39. POLHEMUS INNOVATION IN MOTION 3SPACE FASTRAK USER MANUAL OPMOOPIO02 REV G JUNE 2012 POLHEMUS INNOVATION IN MoTION FASTRAK MANUAL Copyright 2000 2012 by Polhemus Colchester Vermont U S A All rights reserved No part of this publication may be reproduced stored in a retrieval system or transmitted in any form or by any means mechanical photocopying recording or otherwise without the prior written permission of Polhemus No patent liability is assumed with respect to the use of the information contained herein While every precaution has been taken in the preparation of this book Polhemus assumes no responsibility for errors or omissions Neither is any liability assumed for damages resulting from use of the information contained herein 3SPACE and FASTRAK are registered trademarks of Polhemus Polhemus is a Good Manufacturing Practices GMP Contract Manufacturer under U S FDA Regulations We are not a manufacturer of Medical Devices Polhemus systems are not certified for medical or bio medical use Any references to medical or bio medical use are examples of what medical companies have done with the Products after they have obtained all necessary or appropriate medical certifications The end user OEM VAR Distributor must comply with all pertinent FDA CE regulations pertaining to the development and sale of medical devices and all other regulatory requirements FCC Statement This equipment has been tes
40. S FASTRAK MANUAL ISOMETRIC VIEW FOR REFERENCE ONLY THEORETICAL ELECTRICAL CENTER POSITION SHOWN 0 51 Figure 7 10 Receiver Rev G 23 JUNE 2012 POLHEMUS FASTRAK MANUAL INNOVATION IN MOTION 7 15 Stylus The stylus is a pen shaped device with a receiver coil assembly built inside and a push button switch mounted on the handle to effect data output The Position measurements are relative to the tip of the stylus due to a precise factory calibration The Stylus is dimensionally shown in Figure 7 11 and may be used as a receiver in any of the receiver ports However the button on the stylus will only work when the stylus is connected to Station 1 The stylus functions as a receiver with the electrical center offset from the tip of the stylus via software Single or Continuous output records may be obtained as a function of the integral switch See Default Operation with a Stylus on page 90 for operation with a stylus Rev G 24 JUNE 2012 POLHEMUS INNOVATION IN MoTION FASTRAK MANUAL Figure 7 12 Stylus 7 16 Video Sync Detector The Video Sync Detector consists of a suction cup pickup coil with a 3 cable terminated with a subminiature telephone plug The Video Sync is used when the system s data exhibits objectionable noise when operating a receiver in close proximity to any CRT monitor If this condition occurs then Video Sync may be employed using the Video Sync Detector through the software comm
41. SB a device driver must be installed on that computer before USB communication can be established This process is somewhat automatic but requires occasional key strokes by the user during the installation process NOTE the FASTRAK USB port was designed to operate in accordance with the USB 1 0 standard When the USB cable is connected from the FASTRAK to the host computer for the first time the following message will appear Found New Hardware E USB Device Installing Shortly after this message the Found New Hardware Wizard will be launched Install Hardware Device Drivers La SZ Welcome to the Found New A device driver is a software program that enables a hardware device to work with Hardware Wizard an operating system This wizard helps you install a device driver for a hardware device This wizard will complete the installation for this device e USB Device A device driver is a software program that makes a hardware device work Windows needs driver files for your new device To locate driver files and complete the installation click Next What do you want the wizard to do To continue click Next Rev G 29 JUNE 2012 POLHEMUS INNOVATION IN MOTION FASTRAK MANUAL Make sure the CD containing the USB device driver is inserted into the drive before pressing Next in the following window Found New Hardware Wizard Locate Driver Files Let Where do you want Win
42. TING COMMAND X byte s Identification Format I6 Record type 2 Al pem Blank Al S uus Sub record type X Al 4 35 Configuration identification A32 36 37 Carriage return line feed Rev G 80 JUNE 2012 POLHEMUS INNOVATION IN MOTION FASTRAK MANUAL x Position Filter Parameters Syntax Purpose Rev G x F FLOW FHIGH FACTOR lt gt or x n lt gt Macro filter command This command establishes the sensitivity boundary and transition control parameters for the adaptive filter that operates on the position outputs of the tracking system The user can adjust these parameters to fine tune the overall dynamic response of the system F FLOW FHIGH FACTOR a scalar value that establishes the sensitivity of the filter to dynamic input conditions by specifying the proportion of new input data to recent average data that is to be used in updating the floating filter parameter variable Allowable range of values 0 lt F lt 1 a scalar value that specifies the maximum allowable filtering to be applied to the outputs during periods of relatively static input conditions Setting this value to 1 0 disables the filter completely Allowable range of values 0 lt FLOW lt FHIGH or 1 0 to disable a scalar value that specifies the minimum allowable filtering to be applied to the outputs during periods of highly dynamic input conditions Allowable range of values FLOW
43. acker performance shall be regarded as occurring in such a benign environment Built In Test features monitoring the status and health of the tracking system as well as flagging of certain preset conditions monitored by the tracking system software Not to be confused with bit a contraction of binary digit Any procedure that rotates the receiver frame so as to precisely align the receiver to the designated reference frame In a 3SPACE system context the term usually refers to the system software routine that on command performs a coordinate rotation which effectively aligns the receiver frame to a predefined boresight reference orientation Note that the boresight routine accomplishes the boresight orientation of the receiver regardless of the receiver s physical orientation at the instant of boresight initiation So for applications that require the orientation tracking of the body or body member to which the receiver is attached a prerequisite to initiating the boresight function is a physical orientation of the body to be tracked to the boresight reference orientation Bits per second Not to be confused with the signaling or baud rate which is always equal to or higher than the bit rate See baud rate A set of invariable data that allows the 3SPACE to compensate for fixed distortions of the magnetic field due to the surrounding environment The compensation data generally results from an application specific distortion
44. agnetic instruments all measure and output 6DOF data in different optional formats including Cartesian coordinates of position and Euler angles and or direction cosines as orientation parameters The azimuth elevation and roll yaw pitch and roll angles are the more intuitive of the orientation parameters of the receiver and are measured with respect to the alignment or fixed transmitter reference frame Euler angles are defined as the sequence of angles azimuth elevation and roll that define the orientation of the receiver with respect to the X Y Z alignment reference frame Azimuth is a rotation of the receiver s x axis projection in the X Y reference plane about the Z Rev G D 5 JUNE 2012 POLHEMUS INNOVATION IN MoTION FASTRAK MANUAL reference axis Elevation is a rotation of the receiver s x axis about the Y reference axis Rollis a rotation of the receiver s y or Z axis about its x axis In order to measure the orientation Static Accuracy in the same manner that the positional accuracy was obtained the aforementioned precise gimbal test fixture is required to allow input of precise and simultaneously different attitudes As with the positional measurements azimuth elevation and roll measurements of the receiver are taken in a statistically valid number of known attitudes in fixed and known locations throughout the same specified motion box as used for the positional measurements The azimuth elevation and roll error
45. agnetic instruments are treated as black boxes thereby focusing on the performance of the instruments and negating the process of solution from the definitions A key element for determining resolution and accuracy from a black box point of view is the system s signal to noise S N ratio First consider the black box system shown in Figure D 1 The Magnetic Linkage is the magnetic field or B field which is a vector quantity derived from the vector sum of the radial and tangential field components for a magnetic dipole It contains both the magnetic moment vector m and the inverse cube of the range factors given by the quantity K r Rev G D 2 JUNE 2012 POLHEMUS INNOVATION IN MoTION FASTRAK MANUAL MAGNETIC LINKAGE BLACK BOX OUTPUT X Y Z YAW PITCH ROLL ANY GIVEN POSITION amp ORIENTATION MAGNETIC LINKAGE Magnetic Moment POSITION amp ORIENTATION Sensor Loop triad receiving antenna for position and orientation Figure D 2 Black Box System There are three sensing coils and three magnetic moments with the resultant matrix M expressed by M Im m m Position and orientation are described by the voltages induced in the three receiver loops according to their sensitivity and orientation and given by the matrix quantity S si Is 3 Coupling between the Magnetic Linkage and Position and Orientation sensitivity produces nine voltages giving rise to the input voltage matrix expressed as
46. alibration 100 d x Gain Limits Self Calibration 101 e y Gain Limits Self Calibration 102 f z Gain Limits Self Calibration 103 g Coil Limits Self Calibration 104 h Not Used in FASTRAK BIT number Code Signal Matrix Error Codes 105 i Not Used in FASTRAK 106 j A Signal Saturation 107 k A Low Signal 108 1 A Maximum Signal Element Zero BIT number Code EEPROM Error Codes 109 m EEPROM Validity Checksum Error or Data Validity Discrepancy 110 n Reserved for Future Use 111 o Reserved for Future Use 112 p Reserved for Future Use 113 q Reserved for Future Use 114 T Reserved for Future Use BIT number Code Soft Error Codes 115 S Unit Normal Position Vector Reset P R Norm BIT number Code Miscellaneous Error Codes 116 t Compensation Structure Errors Array Size Not In Specification Limits 117 u Compensation Point Not Within Mapped Bounds 118 v No CRT Sync Signal Available 119 W Write Error on Configuration EEPROM 120 X Receiver Out of Motion Box 121 y Euler Angles Outside Allowed Angular Envelope 122 Z Reserved Rev G Identification Format Record type 2 Al Blank Al Sub record type T Al BIT number I3 BIT information A Factory meaningful only Carriage return line feed 71 JUNE 2012 POLHEMUS INNOVATION IN MoTION FASTRAK MANUAL U English Conversion Units Syntax U Description Input output unit is a reference to the distance unit assumed by the system when interpreting input and generating output data Pur
47. and y2 The pickup coil of the Video Sync Detector is attached to the CRT Monitor case and the connector inserted into the Video Sync Detector input After issuing the y2 command the system checks for sufficient signal level from the video pickup coil If the signal level from the pickup coil is below a preset threshold the message no video sync available will be Rev G 25 JUNE 2012 POLHEMUS INNOVATION IN MoTION FASTRAK MANUAL displayed If this condition exists move the pickup coil to another part of the Monitor case This procedure should be repeated until the message no video sync available ceases to occur The video synchronization mode may be exited at any time by selecting another type of synchronization mode using the y command Figure 7 13 Video Sync Detector 7 17 Long Ranger Transmitter The Long Ranger Transmitter is an optional device which produces a larger electro magnetic field and therefore enables greater range capabilities The 18 acrylic sphere is attached to a pedestal which is typically mounted on the optional tripod assembly or suspended from the ceiling The advantage besides longer range when using the Long Ranger Transmitter in lieu of the standard transmitter is a better signal to noise ratio less noise so that whole body tracking can easily be done 7 18 4 Transmitter The 4 Transmitter is an optional device which allows up to 40 more range than the standard 2 Transm
48. apped holes provided on the bottom surface for mounting Nylon hardware supplied should be used when locating the Transmitter in a fixed position NOTE Please be sure to route the transmitter cable separate from the receiver cables in order to avoid possible noise problems 407 104 0mm 4 4 SOURCE 2 SOURCE eg 1 40 D 04 Omm 35 560mm CABLE EXIT v i WT Figure 7 6 Transmitter Diagram Figure 7 7 Transmitter Rev G 21 JUNE 2012 POLHEMUS FASTRAK MANUAL INNOVATION IN MOTION 7 14 Receiver s The receiver is the smaller device whose position and orientation is measured relative to the Transmitter The Receiver is dimensionally shown in Figure 7 8 including the position of the electrical center The Receiver package provides two mounting holes for 4 nylon screws supplied in the event that Receiver mounting is required NOTE Nylon hardware is only required when the hardware will be in direct contact with the transmitter or receiver A testing surface where the devices will be used a table for example could have small metal hardware like screws nuts and bolts which probably would not affect the accuracy of the system Again please be sure to route the receiver cables separate from the transmitter cable 120m Iin I5 PIN CONNECTOR Figure 7 8 RX2 Receiver Dimensions in Inches Rev G 22 JUNE 2012 POLHEM INNOVATION IN U
49. at Al Al Al bSx xxx bSx xxx bSx xxx bSx xxx JUNE 2012 POLHEMUS INNOVATION IN MoTION FASTRAK MANUAL W Reset System to Defaults Syntax Purpose Relatives Default Example Rev G W This command resets all of the system EEPROM variables to their factory default values When using this command the K Save Operational Configuration command page 85 could be used afterwards to save the factory default values to the EEPROM if that is desired Then the Y Reinitialize System command page 88 can be used to reinitialize the system and verify that the factory defaults are now stored in the system EEPROM K Y X N A If the FASTRAK EEPROM had been altered by sending various other commands and saving the result to the EEPROM and the user wanted to return the system to its original factory default settings then the following commands should be sent W K y The green light on the front panel of the FASTRAK will now blink several times while the system is initializing After initialization the system EEPROM will be set with all of the factory default parameters This exercise is especially useful when the system has been modified to the point where the user is not sure how to get back to factory defaults However care should be taken because all custom settings will be lost as a result of the reset 79 JUNE 2012 POLHEMUS INNOVATION IN MoTION FASTRAK MANUAL
50. cycle is completed i e all currently configured stations complete output for this cycle The Stylus switch then serves as a toggle for system output from then on until an RS 232 or USB c command is issued Each toggle will initiate or terminate a continuous stream of output that begins with station one 1 and terminates by a subsequent switch pressing with output for the last station in the cycle list Note that all output begins with the FIRST station in the sequence 1 2 3 4 that is configured ON and ends with the LAST station in the sequence list that is configured ON Configured ON requires both a proper selection switch at power on or enabling the station via the T Active Station State command page 54 Increment functions are as previously defined in this document That is if any receiver does NOT move since its last cycle by an amount equal to or greater than its defined increment output is skipped for the receiver when the above actions cause an output A switch cycle takes 40 system cycles At 8 33 msec per cycle the switch is responsive at a speed of 333 msec or about 1 3 second In other words if the switch is held down while the system is in NON continuous mode an output cycle is generated as if a P Single Data Record Output command page 63 is entered at the rate of 3 second If the switch is pressed twice within the 333 msec window the second pressing is ignored See the e Defin
51. dard RS 232 serial configuration or the optional RS 422 configuration Each configuration supports either Binary or ASCII formats RS 232 The RS 232 is the most commonly used port both in binary and ASCII formats because of its commonality and the fact that it supports high baud rates The RS 232 port should be used where host to FASTRAK physical separation distances are no greater than 50 feet and baud rates can be kept low Higher baud rates will require shorter cable lengths for reliable operation Ensure that your RS 232 cable connects the FASTRAK TRANSMIT data pin pin 3 to the HOST S RECEIVE data pin and that the FASTRAK RECEIVE data pin pin 2 is connected to the HOST S TRANSMIT data pin Also ensure that the RS 232 cable connects the FASTRAK GROUND pin 5 to the HOST S GROUND pin Note that the host computer s ground pin may be designated as Signal Ground or some other comparable phrase RS 232 Cable Connections FASTRAK HOST Transmit pin 3 Receive Receive pin 2 Transmit Ground pin 5 Ground RS 422 The optional RS 422 port is used where large separation distances between the FASTRAK and the host are anticipated If high baud rate operation over a long communication cable is required but the host computer does not have an RS 422 inexpensive RS 422 RS 232 conversion modules are availab
52. dows to search for driver files e Search for driver files for the following hardware device e USB Device The wizard searches for suitable drivers in its driver database on your computer and in any of the following optional search locations that you specify To start the search click Next If you are searching on a floppy disk or CD ROM drive insert the floppy disk or CD before clicking Next Optional search locations E Y Vv Specify a location Microsoft Windows Update Found New Hardware Wizard Hardware Install Windows is installing drivers for your new hardware Fastrak Loader MZ Ins Found New Hardware Wizard J Driver Files Search Results The wizard has finished searching for driver files for your hardware device Sy The wizard found a driver for the following device p USB Device Windows found a driver for this device To install the driver Windows found click Next cg a ftusb inf Completing the Found New Hardware Wizard 9 Fastrak Loader Windows has finished installing the software for this device To close this wizard click Finish i Cancel At this point the device driver installation is complete and the host computer should be ready to communicate with the FASTRAK over the USB port with the user s application software To verify USB communication using the Polhemus GUI double click on the FASTRAK GUI icon FT GUI In the
53. e Relatives Default Example Rev G y smode Or y to read back the current synchronization mode Synchronization allows for any one of four conditions 1 The FASTRAK system can operate in its default condition with the data cycle time set to 8 3 milliseconds This can be achieved by setting the system to Internal Sync Mode 2 Oneto four FASTRAK systems can operate in relatively close proximity without interfering with each other The interference is generally seen as noise where measurements change without physically moving receiver position or orientation This can be achieved by setting the system to External Sync Mode and linking the systems together with a sync cable 3 The FASTRAK cycle time can be set externally with a sync pulse generator This can be achieved by setting the system to External Sync Mode and connecting to the external pulse 4 The FASTRAK receivers can operate in relatively close proximity to a CRT video monitor without picking up interference This can be achieved by setting the system to Video Sync Mode and connecting the video sync detector between the FASTRAK and the CRT monitor This command allows the host to set the system synchronization mode The specific parameters are smode Description 0 Internal Sync Mode Signifies that the system is synced internally 8 3 milliseconds cycle time 1 External Sync Mode Signifies that the system is externally synced to another FASTRAK sy
54. e free run 1 External 2 CRT 5 6 Carriage return line feed Rev G 84 JUNE 2012 POLHEMUS INNOVATION IN MoTION FASTRAK MANUAL AK Save Operational Configuration Syntax Definition Purpose Relatives Default Example Rev G AK EEPROM Electronically Erasable Programmable Read Only Memory is memory that can be altered by the system but is not lost when the power is turned off System variables are stored in the EEPROM All of these variables are assigned default values The values are assigned to these variables at the factory and are therefore called the factory defaults The default values are applied to the variables at initial power up and system reset This command allows the user to save the current state of the system configuration parameters to the system EEPROM This state is henceforth the power up state until another K Save Operational Configuration command page 85 is issued NOTE There may be a short pause of several seconds while the system executes this command Y W X N A If the system were used in an application where only position measurements on station 1 were required and they had to be in metric units the following commands should be sent 1 O1 2 1 lt gt 2 u 3 K The system will now be configured to output metric position measurements only on station one each time it is powered on 85 JUNE 2012 POLHEMUS INNOVATION IN MoTION FASTR
55. e the adaptive feature varies the pole location between the FLOW and FHIGH limits so as to maximize the output resolution for static inputs while minimizing the output lag for dynamic inputs Whenever the input conditions cause the filter to make a transition to a narrower bandwidth 1 e increased filtering the transition rate of the pole location is constrained to a maximum allowable rate by the parameter FACTOR If all of the optional parameters are omitted the current value of each parameter is returned to the user as an output record of type v None The default mode for all filter parameters is medium These settings may be used as a starting point for determining optimum filtering in your particular environment F 0 2 FLOW 0 2 FHIGH 0 8 FACTOR 0 95 Although they are already stored in the system EEPROM medium filtering can be selected by sending the following command to the system v 2 2 8 95 lt gt All active stations will now have medium filtering applied to the attitude measurements 77 JUNE 2012 POLHEMUS INNOVATION IN MOTION RECORD IDENTIFIER INITIATING COMMAND V Rev G byte s 2 seek Does 4 10 11 17 18 24 25 31 as 32 33 Identification Record type 2 Blank Sub record type v Filter sensitivity Floating filter low value Floating filter high value Transition rate maximum Carriage return line feed 78 FASTRAK MANUAL Form
56. e Figure 9 1 on page 36 An example of where this command would be useful is a sloped test surface that the user wanted referenced to the transmitter This would obtain congruence between the FASTRAK and the axes of the sloped surface NOTE This command operates incrementally If the command is entered and the user then decides to change it the R Reset Alignment Reference Frame command page 66 must be used to reset the alignment reference frame BEFORE the command is re entered This is ESPECIALLY IMPORTANT to remember if the user makes an error and wants to correct the erroneous input because the new alignment would be additive to the mistake The command parameters are station to 4 which specifies the relevant transmitter receiver pair Ox Oy Oz the Cartesian coordinates of the origin of the new reference frame Xx Xy Xz the coordinates of the point defining the positive direction of the X axis of the new reference frame Yx Yy Yz the coordinates of a third point that is in the positive Y direction from the X axis R No Range Restriction Enforced The transmitter reference frame is the default alignment reference frame 0 0 0 200 0 0 0 200 0 in centimeters To perform an alignment on station 1 follow the steps listed below Standard Alignment Procedure 1 Send the command R1 2 Place the receiver at the proposed origin location 3 Press P and write down the X Y Z measurements These will be Ox Oy Oz 4 Mo
57. e Short Ranger Transmitter sssessseeeneeeee 26 Power Reguirementz signal to noise S N ratio D 3 power up Single Data Record Oummut 63 Powering Up FASTRAK sse Bpecifeaton EE A 12 printed circuit board DCH Standard Alignment Procedure sss 37 PROM ou deum shut eet a A data a tereti Static ACCULACY ien tne ii eser 12 Eng P 54 QualteED OD eese eim edo esci ssren irre rabat e WEI read system identification information TECEIVED soient nier feine REGELV Cf c Receiver Input s EP Receiver Ports 4 oo ede e tren een he ene bere RECEIVE S hesesare r E EN 22 Reinitialize System eectteere 16 79 88 System Block Diagram seen D 2 reset alignment reference frame v u 37 System Cominards oett rrr eto eene 34 Reset Alignment Reference Frame 66 System Data Record Reset System to Defaite 79 80 ASCII Format i eene nnne resolution D 1 D 4 IEEE Floating Point Format Resolution vs Range cesceesceeseeesseeeeeeeeneeeeneeseeeseeeeaes 12 System Electronics Unit SEU Resume Data Transmission 86 87 System ID Data returning merchandise essere 8 System Operation Roll system re initialization esses roll mounting frame sees 67 System Status Record cca Mn LA MO D MILLS
58. e Stylus Button Function command page 45 for other options and operational information Rev G 90 JUNE 2012 POLHEMUS INNOVATION IN MoTION FASTRAK MANUAL APPENDIX A Limited Warranty and Limitation of Liability Polhemus warrants that the Product shall be free from defects in material and workmanship for a period of two years from the date of Polhemus delivery to the Buyer or two years and 30 days from the date ownership of Product passed to the Buyer whichever occurs first with the exception of FastSCAN Marker and mechanical failure of a battery assembly which have a watranty period of only one year Batteries have a 90 day warranty period Polhemus shall upon notification within the warranty period correct such defects by repair or replacement with a like serviceable item at Polhemus s option This warranty shall be considered void if the Product is operated other than in accordance with the instructions in Polhemus s User Manual or is damaged by accident or mishandling Parts or material which are disposable or expendable or subject to normal wear beyond usefulness within the warranty period such as lamps fuses etc are not covered by this warranty In the event any Product or portion thereof is defective Buyer shall promptly and within the watranty period notify Polhemus in writing of the nature of the defect and return the defective parts to Polhemus at the direction of Polhemus s Customer Service representative Upon
59. e output list refers to the subset of data items to be included in a data record Any combination of up to 32 data items that total less than or equal to 254 bytes is permissible This command allows the user to define the list of variables to be output to the host computer for the specified station Any combination of up to 32 data items that total less than or equal 254 bytes is permissible The allowable values of the parameters are 0 ASCII space character 1 ASCII carriage return line feed pair 2 x y z Cartesian coordinates of position 3 relative movement x y z Cartesian coordinates of position i e the difference in position from the last output This item should only be selected if the specified station s Increment is 0 0 See the T Define Increment command page Seck A azimuth elevation roll Euler orientation angles 5 X direction cosines of the receiver s x y z axes See Note 1 6 y direction cosines of the receiver s x y z axes See Note 1 7 Z direction cosines of the receiver s x y z axes See Note 1 8 not used 9 not used 10 not used 11 orientation quaternion 12 not used 13 not used 14 not used 15 not used 16 stylus switch status 17 not used 18 not used 19 16not used 20 not used 21 49 not used reserved for future use Extended precision 50 66 50 ASCII space character same as 0 51 ASCII carriage return line feed pair same as 1 52 x y z Cartesian coordinates of posit
60. eiver pair Up to four receivers are permitted yielding a possible four stations A pencil shaped housing for the receiver with an integral switch and used by the operator to indicate and or select points to be digitized Shorthand for synchronization For example sync signal C 6 JUNE 2012 POLHEMUS INNOVATION IN MoTION FASTRAK MANUAL System ID Data Tracker Alignment Thirty two characters of ASCII data hardware serial number etc stored in EEPROM containing information identifying the system See X command The process whereby the tracking system coordinate reference is brought into coincidence either physically or mathematically with other coordinates of the environment Tracker Calibration The process whereby the tracking system is made to operate accurately in Tracker Latency Tracker Response Transmitter Units Update Rate Useful Range Rev G the installed environment to produce tracking data throughout the motion box The interval of time between when tracker measurement data were collected and when the P amp O result is formatted ready for transfer to the host computer In some systems namely active trackers there is a timer interval when the active element is illuminating the environment when the data are collected after which the P amp O computation can be done Hence this definition is intended to correspond to the center point of data collection time so that tracker latency is strai
61. er key An ellipsis indicates that you can repeat an item A comma represents a delimiter in a list of optional parameters The comma must be present for those parameters which are omitted except for the case of trailing commas For example Qs p1 p4 lt gt is the proper command format when omitting parameters p2 and p3 Commas following the parameter p4 are not required if parameters p5 and p6 are omitted A vertical bar means either or Choose one of the separated items and type it as part of the command For example ONIOFF indicates that you should enter either ON or OFF but not both Do not enter the vertical bar Used in text to indicate the Ctrl key C 8 JUNE 2012 POLHEMUS INNOVATION IN MoTION FASTRAK MANUAL APPENDIX D Accuracy and Resolution White Paper ACCURACY AND RESOLUTION IN ELECTROMAGNETIC 6 DEGREE OF FREEDOM 6DOF MEASUREMENT SYSTEMS APB 8500 0014 INTRODUCTION The classical definitions of resolution and accuracy as articulated by Cook and Rabinowicz in Physical Measurement and Analysis Addison Wesley Publishing Company 1963 are Resolution the smallest amount of the quantity being measured that the instrument will detect Accuracy the fractional error in making a measurement Clearly confusion over these issues in light of the burgeoning need to measure both the position and orientation of a freely movable object in space with respect to a fixed reference can lead t
62. er Parameters ccccccccsscccesssecessseeeessseeeees 76 Attitude Matrix qe TP C 1 Azimuth azimuth mounting frame sse 67 baud rate ssssssseseeeeeennneeen nennen 16 62 C 2 Benign Environment C2 Dii t M 12 BIT Built In Test etre re tems 60 C 2 JEN I 70 DIS eiecti 62 Black Box System D 3 boresight Boresight Boresight Reference Angles eee 49 hoc Built In Test BIT Built In Test Information ccccccccccessseceesseeeeeeee 60 70 Cable Diagram 25 Pni Female onion nire F 2 O Pin Female 5 rrt teo CEN F 1 Cable DiaBratn s ded eie e a reete 19 F 1 Carrier Frequency eonim han enit s 13 REV G Cartesian coordinates esesseseeeeeenneneees 12 58 Cenitimeters ro roo inem ie ren ODE ERE HER EUER ET 73 character width e ie tie etitm eee hene nean 16 check for BIT ettOIs corretti iei ree xe 68 Command Error geniert bre re tnt erre Reds 89 Command Format Notation and Convention 34 Command Format Notes Command Output Lietng eee 36 COMPENSALIOMN esee emt rrt aree ese rera ed praedio d Compensation Data vs Component Description esee 15 CONCOMT c Configuration Changes Configuration Control Data 80 Contacting Polhemus eere continuous output mode COP YTS ac sce ccrte o epe r
63. ered on 8 4 Using the USB Interface When the FASTRAK is powered on it is enabled for RS 232 communication As soon as the USB cable is plugged in the FASTRAK will shift to USB operation see Figure 8 1 on page 29 It takes the FASTRAK approximately 3 4 seconds to shift to USB mode Since the FASTRAK can not communicate over the RS 232 port and the USB port simultaneously the user needs to choose which interface will be used and cease communication over the other port Once the FASTRAK is in the USB mode simply disconnecting the USB cable will not put the FASTRAK back in RS 232 mode In order to switch the FASTRAK back to RS 232 mode the user must disconnect the USB cable and then cycle the power on the FASTRAK turn it off then turn it back on again Note that at anytime during RS 232 operation the USB cable can be plugged into the FASTRAK and it will switch to USB mode without having to cycle the power However it is best to disable continuous output mode and close any programs communicating with the FASTRAK via RS 232 first in order to avoid error messages or program lock ups while switching to the USB mode Rev G 28 JUNE 2012 POLHEMUS INNOVATION IN MoTION FASTRAK MANUAL Figure 8 1 Connection of USB Cable to Switch to USB Mode 8 5 Installing USB Device Drivers NOTE The following USB Device Driver was designed to run on Windows 2000 and Windows XP The first time the FASTRAK is connected to a new host computer via U
64. erefore if you change the switches to obtain a different baud rate you must restart the system either by recycling the power or by using the Y Reinitialize System command see page 88 Rev G 16 JUNE 2012 POLHEMUS INNOVATION IN MoTION FASTRAK MANUAL The o Set Output Port command page 62 may be used to override the switch settings during operation and select other baud rates Although it is possible to save the new baud rate with the AK Save Operational Configuration command see page 85 the next time you power up or re initialize the system with the Y Reinitialize System command page 88 the system will ignore the EEPROM baud rate setting and read the dip switch settings to operate at that baud rate NOTE High baud rates such as 115 2K generally require a short well made RS 232 cable in order to achieve error free performance The Hardware Handshake function has been discontinued in this FASTRAK version Switch 4 has no effect The Parity select logic for switches 6 and 7 is as follows Parity 6 7 None 0 0 Odd 1 0 Even 0 1 Not used 1 Caution System will not operate in this position P N 1A0383 001 Freq FASTRAK S N 407A90030 PoLHEMUS Figure 7 3 Default I O Select Dip Switch Settings 7 6 External Sync I O The External Sync I O module is located on the rear panel of the SEU as shown in Figure 7 4 The connector contains two modular telephone sockets wit
65. eset ede acea eee A SERERE ERE UY Current FASTRAK vs Previous Versions customer Service AER Default Operation with a Stylus 11 24 90 Define Increimient d eiie Rete 53 define stylus button function 45 90 Define Tip O fSetS isi rr tee the RRS 56 determine system configuration eee 68 determine the firmware version number 68 Device Driver Installation eeeeeeene 30 npe cL 3 DOINGS ME F 4 Direction S rr Cx Disable Continuous Printing eee Disable Fixed Metal Compensation distance Unit onere riri pete e e EC Declaration of Incorporation see ii EEPROM eegne pit e ati gei deeds 79 85 C 3 effective latent period E 1 electro magnetic Elevation iiir crr reme cde to i ee elevation mounting frame sees Enable ASCII Output Format Enable Binary Output Format eese enable fixed metal compensation sese 43 English Sege eit te ots 5 12 72 English Conversion Units eee 72 Enhanced Alignment Procedure uses 38 envelope lirniits i oceeoisece neenon tnit 74 Euler M M 12 Euler angles eie ertet et 58 Euler orientation angles see 58 External Sync iiie eee recti 31 External Sync I O s 12 17 External Sync Mode
66. fication Format lust Record type 2 Al d sees Station number Al oer Sub record type T Al 4 10 Distance required to move Sxxx xx 11 12 Carriage return line feed 53 JUNE 2012 POLHEMUS INNOVATION IN MoTION FASTRAK MANUAL T Active Station State Syntax Description Purpose Relatives Default Example Rev G lstation state Or lstation lt gt to read back the current station state A station is defined as a transmitter receiver pair The four receivers paired with the one transmitter are assigned station numbers one through four 1 4 Although stations are enabled simply by plugging the receivers into the ports on the FASTRAK SEU the stations can then be disabled or enabled again by using a software command When a station 1s enabled data records for that receiver will be transmitted from that station If the station 1s disabled no data records from that station will be transmitted The purpose of this command is to allow the host to turn a station on or off in software The command parameters are identified as follows station 1to4 state 0 off on None The default condition depends on the number of receivers that are currently connected to the FASTRAK SEU The default condition of a station that has a receiver connected to it is a 1 or station on The default condition of a station that does not have a receiver connected to it is a 0 or
67. g Command Sequence W 4K Y Resets System Defaults BIT Error n w Return SEU for Repair BIT Error s Reduce Range Return SEU for Repair BIT Error Gu Test with Compensation Turned Off Send d Command Rev G B 1 JUNE 2012 POLHEMUS FASTRAK MANUAL INNOVATION IN MOTION APPENDIX C Glossary 6DOF The 6 Degrees Of Freedom XYZAER needed to define the position and orientation of an object in 3D space Alignment Obtaining congruence between the axes of the tracker and the axes of the application For active technologies this is often the same as aligning the active element from which all measurements are referenced Alignment in an active system is not the same as a boresight operation which concerns only the receiver Only in passive systems alignment and boresight can be identical Alignment Frame The reference frame in which the position and orientation of the receiver is measured The default alignment frame is the transmitter frame ASCII American national Standard Code for Information Interchange defines a certain 8 bit code for display and control characters Attitude Matrix A three by three matrix containing the direction cosines of the receiver s x axis in column one the direction cosines of the receiver s y axis in column two and the direction cosines of the receiver s z axis in column three The order of the 3SPACE Euler angle rotation sequence is azimuth elevation and roll X
68. ghtforward and understandable as stated Other tracking systems e g inertial may produce raw data continuously or nearly continuously Tracker latency in this case reduces to the computation time for producing the answer ready for transfer to the host computer The interval of time between a request to the tracking system to collect a data point and when that data is available for input from the tracker The transmitter generates the low frequency magnetic field measured by the receiver The transmitter s X Y and Z axes are the default measurement reference frame The unit of assumed distance The 3SPACE allows either inches or centimeters The rate at which motion tracking data can be made available from the tracking system The maximum distance at which the resolution and noise performance of the tracking system can be realized C 7 JUNE 2012 POLHEMUS INNOVATION IN MoTION FASTRAK MANUAL User Defaults XYZ or X Y Z XYZAER Yaw lt gt Rev G The values assigned to certain system variables by the user Stored in EEPROM the system receives these variable values at power up The Cartesian coordinates of position tracking where normally X is in the forward direction Y is in the right hand direction and Z is upward The output string of date reporting the position XYZ and orientation AER azimuth elevation and roll of the tracking receiver Same as azimuth Used in text to indicate the Ent
69. gnificant bit The volume in which motion tracking is guaranteed to perform as prescribed Although this 3D volume usually is cubicle in nature many of the tracking technologies known as active are dependent on a source of stimulation e g magnetic field light transmitter which actually performs equally well at a constant radius from the source so that the box actually might be better described as spherical or hemispherical The azimuth elevation and roll angles that define the current orientation of the receiver coordinate frame with respect to the designated reference frame The Euler angle coordinates that are output by the 3SPACE as one measure of receiver orientation are graphically defined in Figure C 1 In Figure C 1 the x y z and X Y Z tri axis arrays represent independent three dimensional orthogonal coordinate frames The x y z triad represents the receiver frame in its current orientation state The X Y Z triad represents the reference frame against which the relative orientation of the receiver frame is measured By definition then the X Y Z frame also represents the zero orientation reference state of the receiver frame C 4 JUNE 2012 POLHEMUS INNOVATION IN MoTION FASTRAK MANUAL Output List P amp O Rev G X Y Z Alignment Reference Frame X y Z Rotated Stylus or Sensor Coordinate Frame Y Azimuth 0 Elevation Roll Figure C 1 Euler Angles The 3SPACE Euler angles azimuth
70. h the one closest to the I O Select Switch being Sync In The input signal must be a single ended TTL signal If the output is employed in the user s system it should be interfaced with differential TTL circuitry The Sync Out signals are also compatible with RS 422 specifications The signal logic is as follows Input START Logic LOW to HIGH transition 50 usec pulse min Output START Logic LOW to HIGH transition 50 usec pulse min NOTE The Sync Out feature is no longer available on FASTRAK models produced as of January 2012 The pin assignments for each plug are as follows and their numbering is shown in Figure 7 4 Rev G 17 JUNE 2012 POLHEMUS INNOVATION IN MoTION FASTRAK MANUAL RESERVED 8A RESERVED 7A RESERVED 6A RESERVED 5A RESERVED 4A RESERVED 3A RESERVED 24 SYNCIN 14 RESERVED 8B RESERVED 7B SYNC OUT 6B RESERVED 5B RESERVED 4B SYNC OUT 3B GND 2B NOTUSED 18 OUT SYNC INTERFACE MATING FACE SHOWN Figure 7 4 Sync Connector Identification Input and Output NOTE If a ground is required use a shielded cable and use the shield as the ground reference 7 7 Frequency Select Module The Frequency Select Module is used to select the operating carrier frequency of the FASTRAK system It is located inside the SEU directly behind the Transmitter input connector The alternate carrier frequencies are produced by inserting the required tuning module in the socket provided
71. hen the initial USB connection is made If you are not planning to use the USB port you may remove the CD ROM from the drive now USB Driver Installation Rev G When FASTRAK is connected via USB to a Windows host for the first time the host will display a Found New Hardware message The host will then launch the Found New Hardware Wizard to locate and install the USB drivers for FASTRAK If the CD ROM is not already in the drive load it now When the Found New Hardware Wizard displays select the Install software automatically option and then Next The wizard will install the FASTRAK Loader When it has completed select Finish The same process will be launched again automatically to install the Polhemus FASTRAK USB Driver Repeat the same selections and the process will be complete 4 JUNE 2012 FOE FASTRAK MANUAL 8 Use the Polhemus PiMgr GUI If you selected the default settings when you installed the FASTRAK Host Software on your computer you will find a shortcut to the PIMgr application on your Windows XP Vista Win 7 desktop It looks like this Otherwise navigate to the program through the windows Start menu Start gt All Programs gt Polhemus gt PiMgr The initial PiMgr screen will look like this Rev G Figure 1 8 PiMgr Screen Display a With no FASTRAK system connected notice that the 2M icon appears in the lower right corner Once connected the icon will change to
72. hes the position operational envelope limits If the X Y Z output measurements are outside the limits defined by this command the system will produce a BIT error x The specific parameters are s the number of the station whose position limits is to be returned or established xmax the maximum x coordinate for the position operational envelope ymax the maximum y coordinate for the position operational envelope zmax the maximum z coordinate for the position operational envelope xmin the minimum x coordinate for the position operational envelope ymin the minimum y coordinate for the position operational envelope zmin the minimum z coordinate for the position operational envelope Relatives Q Default 78 74 78 74 78 74 78 74 78 74 78 74 200 200 200 200 200 200 in centimeters Example If the user wanted to reduce the position operation envelope to a 30 cube the following command should be sent V1 30 30 30 30 30 30 lt gt The system will now output an error x any time the 30 inch limit is exceeded in any of the axis for station 1 RECORD IDENTIFIER V INITIATING COMMAND V Rev G 74 JUNE 2012 POLHEMUS INNOVATION IN MOTION Rev G byte s E 2 s 3 s 4 11 12 19 20 27 28 35 sins 36 43 44 5 52 53 4 Identification Record type 2 Station number Sub record type V Maximum x coordinate value Maximum y coordinate value Maximum z coordina
73. inary format is generally computer readable Regardless of output data format selected all input data commands to the FASTRAK system must be in ASCII format f The default output data format is ASCII If a software application is written to receive binary data from the FASTRAK system and there was a requirement to take it offline temporarily to do visual checks the user would enable the ASCII output data format in order to be able to easily read the FASTRAK data on the PC monitor To do so the following command should be sent F The system will now be in ASCII output data format and can be read by the user 46 JUNE 2012 POLHEMUS INNOVATION IN MoTION FASTRAK MANUAL f Enable Binary Output Format Syntax Purpose Relatives Default Example Rev G f This command enables the binary output data format Binary format is generally computer readable while ASCII format is human readable This format is a 32 bit floating point output that is in accordance with the format specified by ANSI TEEE Std 754 1985 Specification for Binary Floating Point Arithmetic F The default output data format is ASCII The user may wish to write a software application for the FASTRAK where a fast update rate is crucial In order to reduce data packet size the FASTRAK could be set to output in binary instead of ASCII This can be accomplished with the command f The FASTRAK will now output binary data The notation S
74. inches Y position in inches Z position in inches Azimuth attitude in degrees Elevation attitude in degrees Roll attitude in degrees Oo LN P GA A rz Because you have locked the receiver in one position relative to the transmitter Step 4 the data output will not change regardless of the number of data samples you take Remove the receiver move it approximately six inches toward the transmitter secure it in place and take a data point The value of the X position data will decrease by approximately six inches The Y and Z values will remain roughly the same as the original data If you left the attitude of the receiver approximately the same as it was when you started then the attitude data will be approximately the same also Again remove the receiver and without moving its position try twisting it in azimuth in the same plane as the 2 x 4 approximately 45 degrees and lock it down with tape Now take another data point by clicking a single button or using the P Single Data Record Output command page 63 The first four columns will be approximately as they were in Step 10 but the Azimuth data in column 5 will have changed by approximately 45 degrees Experiment with the system as shown in Step 12 to demonstrate that it measures the position and orientation 6DOF of the receiver with respect to the transmitter If the system fails to produce 6DOF data carefully go over the above procedure in a systematic fash
75. ingleFP refers to the ANSI IEEE Standard for Binary Floating Point Arithmetic 754 1985 format of data This is defined in the standard as MSB LSB Bit 31 Bit 30 23 Bit 22 0 Sign Exponent Fraction Byte 3 Byte 2 Bytel ByteO The IEEE floating point format uses sign magnitude notation for the mantissa and an exponent offset by 127 In a 32 bit word representing a floating point number the first bit is the sign bit The next 8 bits the exponent offset by 127 i e the actual exponent is e 127 The last 23 bits are the absolute value of the mantissa with the most significant 1 implied The decimal point is after the implied 1 or in other words the mantissa is actually expressed in 24 bits In the normal case an IEEE value is expressed as 1 S 2 e 127 O1 f If0 lt e lt 255 In special cases 1 S 0 0 Ife 0 andf 0 1 8 2 126 0 f Ife 0 and f lt gt 0 denormalized 1 S infinity If e 255 and f 0 infinity NaN not a number If e 255 and f lt gt 0 The actual I O byte sequence is system specific For the greatest compatibility Polhemus has adopted for output the following Intel 80X86 byte ordering 47 JUNE 2012 POLHEMUS INNOVATION IN MoTION FASTRAK MANUAL The lowest physical address for a byte is a0 al has address a0 1 etc The least significant byte of data is bO with b3 the most significant byte For IEEE FP output from the Tracker Dig
76. ion 53 relative movement x y z Cartesian coordinates of position i e the difference in position from the last output This item should only be selected if the specified station s Increment is 0 0 See the T Define Increment command page 33 54 az el roll Euler orientation angles 55 X direction cosines of the receiver s x y z axes See Note 1 57 JUNE 2012 POLHEMUS INNOVATION IN MOTION FASTRAK MANUAL 56 y direction cosines of the receiver s x y z axes See Note 1 57 z direction cosines of the receiver s x y z axes See Note 1 58 not used 59 not used 60 not used 61 orientation quaternion 62 not used 63 not used 64 not used 65 not used 66 stylus switch status 67 not used reserved for factory use 68 98 not used reserved for factory use 99 not used reserved for factory use Relatives None Default 0s 2 4 1 i e the three Cartesian coordinates the three Euler orientation angles carriage return and line feed for stations 1 through 4 Example The user may decide to use X Y Z direction cosines instead of the default output format In order to do so the following command should be sent O1 5 6 7 1 lt gt The output data for station will now be displayed as X Y Z direction cosines RECORD IDENTIFIER O INITIATING COMMAND O byte s ls p Rev G Identification Format Record type 2 Al Station number Al Sub record type O Al Data item 0
77. ion checking connections and switch settings especially When all else fails call us Rev G 7 JUNE 2012 POLHEMUS INNOVATION IN MoTION FASTRAK MANUAL 2 Contacting Polhemus Customer Service If problems are encountered with the FASTRAK system or if you are having difficulty understanding how the commands work help is just a telephone call away Call Polhemus at 800 357 4777 and select 2 for Customer Service and then 1 for Technical Support Polhemus is open Monday through Friday 8 00 AM to 5 00 PM Eastern Standard Time For the most part our customer service engineers are usually able to solve problems over the telephone and get you back into the fast lane right away Help is also available on our web page at www polhemus com Simply double click Technical Support then select techsupport polhemus com to send us an email describing the problem or question If a problem requires repair of your system the customer service engineer will issue a Return Merchandise Authorization RMA number so you can return the system to the factory Please retain and use the original shipping container if possible to avoid transportation damages for which you or your shipper would be liable Please do not return any equipment without first obtaining an RMA number If your system is still under warranty Polhemus will repair it free of charge according to the provisions of the warranty as stated in APPENDIX A of this document The proper
78. ion limits This command allows the user to set maximum and minimum limits for the azimuth elevation and roll outputs If the orientation outputs are outside of the limits defined by this command the system will output an error y The specific parameters are s the number of the station whose angular limits are to be established azmax the maximum azimuth value for the angular operational envelope elmax the maximum elevation value for the angular operational envelope rlmax the maximum roll value for the angular operational envelope azmin the minimum azimuth value for the angular operational envelope elmin the minimum elevation value for the angular operational envelope rlmin the minimum roll value for the angular operational envelope V 180 90 180 180 90 180 If the FASTRAK system outputs were to be used to drive a gimbaled system that had physical orientation limits then it would be a good idea to set the FASTRAK angular operational envelope to those limits Suppose the gimbaled system had azimuth and elevation limits of 45 degrees The following command should be sent Q1 45 45 180 45 45 180 lt gt The FASTRAK data will now contain an error y each time the azimuth or elevation limit is exceeded In addition the application software should be programmed to ignore any data record containing the y error to avoid causing the gimbaled system to slam into a limit RECORD IDENTIFIER
79. itizer the byte output sequence is bO b1 b2 amp b3 a0 al a2 ag b0 b1 b2 b3 80X86 b2 b3 b0 b1 DEC PDP 11 b3 b2 b1 b0 Z8000 M680XX Rev G 48 JUNE 2012 POLHEMUS INNOVATION IN MoTION FASTRAK MANUAL G Boresight Reference Angles Syntax Purpose Relatives Default Example Gstation Azref Elref Rlref Or Gstation lt gt to read back the current boresight reference angles This command establishes the bore sight reference angles for a particular station When the system is boresighted with the B Boresight command see page 39 the line of sight vector Azimuth Elevation and Roll angles will assume these values If all the optional parameters are omitted the system returns the boresight reference angles for the specified station as an output record of type G The command parameters are defined as station the number of the station whose reference angles are to be fixed Azref the azimuth reference angle Elref the elevation reference angle Rlref the roll reference angle B b The system default boresight reference values are 0 0 0 The user may wish to set the boresight reference values to an orientation that corresponds with the application For example if the application required an output of 0 15 0 following a boresight reference angles should be applied with the G command G1 0 15 0 lt gt The boresight command B1 lt gt will now cause the azimuth
80. itter The 4 Transmitter can be employed in virtually the same environments as the standard transmitter and even uses the same mounting hole pattern allowing increased range without degradation in the data 7 19 Short Ranger Transmitter The Short Ranger Transmitter TX1 is an optional device which produces a smaller electro magnetic field for precision work in a restricted space It is dimensionally the same as the receiver and is shown in Figure 7 6 on page 21 There are two advantages when using the Short Ranger Transmitter in lieu of the standard transmitter a small volume means 1 less susceptibility to field distortions with metals nearby and 2 no concern about transmitter aperture when closely approaching the device The Short Ranger requires a factory modification to the SEU which needs to be addressed when the product is ordered other transmitters can no longer be operated by the modified SEU 7 20 Mini Receiver The Mini Receiver is an optional device 10 12 mm in size whose position and orientation is measured relative to the transmitter like all receivers Because of its small size its maximum range from the transmitter is reduced to 35 40 that of a standard receiver Refer to Figure 7 9 on page 23 Rev G 26 JUNE 2012 POLHEMUS INNOVATION IN MoTION FASTRAK MANUAL 8 System Operation 8 1 I O Considerations Currently there are two possible interface configuration options available on the FASTRAK system the stan
81. iver moving at constant velocity will correspond to where the receiver was at t t 2 the midpoint of the sampling period hence the effective latency is T t 2 or 3 75 ms OTHER FACTORS Although the time to transmit data is not included in the definition of latent period a knowledge of how to compute these delays is needed to properly align in time the receipt of tracker solution with the actual event For example the factory default ASCII output record x y z az el rl is composed of 47 bytes 3 status bytes 6 data words each 7 bytes long and a CR LF terminator and at 115 2K Baud requires a transmission time of 4 ms recall that there is one start bit and one stop bit per 8 bit data byte The tracker s sync to output latent period plus transmit time for this example is 9 5 ms and the effective latent period plus transmit time is 5 8 ms It is very important to note that if the transmit time exceeds the tracker cycle time 8 33 ms which could happen if the baud rate is too slow or if the record length is too long it becomes necessary for the tracker to periodically discard solutions to prevent output buffer overflow This would make it appear as though the tracker was not tracking continuously or was dropping data This interface problem is most noticeable in multiple receiver operation as the tracker is designed to maintain constant order of receiver processing If the interface just missed a given receiver in the list of multiple receive
82. lags LSBit nABRWNR CH 6 9 Output Format Units Compensation Transmit Mode Configuration Always 1 Reserved FASTRAK MANUAL Format AI AI AI H3 0 ASCIL Binary O2Inches Centimeters 0 Off 1 On 02Non Continuous Continuous 1 Tracker Reserved for future use 10 23 Reserved for future use MSBit BIT error Blank Reserved for future use F3 ID Tag Sensor Map Blank Reserved Software Version ID System Identification See X Carriage return line feed I Al A6 A32 The system s configuration status is contained as a hexadecimal number in the fourth fifth and sixth columns of the S command output For convenience the following table lists the hexadecimal number and corresponding system configuration HEX Code Continuous Mode Compensation Units Output 3FF ON ON CM Binary 3FE ON ON CM ASCII 3FD ON ON IN Binary 3FC ON ON IN ASCII 3FB ON OFF CM Binary 3FA ON OFF CM ASCII 3F9 ON OFF IN Binary 3F8 ON OFF IN ASCII SET OFF ON CM Binary 3F6 OFF ON CM ASCII 3F5 OFF ON IN Binary 3F4 OFF ON IN ASCII 3F3 OFF OFF CM Binary 3F2 OFF OFF CM ASCII 3F1 OFF OFF IN Binary 3F0 OFF OFF IN ASCII Rev G 69 JUNE 2012 POLHEMUS INNOVATION IN MoTION FASTRAK MANUAL T Built In Test Information Syntax TBITnumber 0 lt gt Purpose This command allows the user to obtain additional information about a particular BIT and clear a BIT error The additional information
83. ld be synchronized and data records should be reduced to the minimum required Also use the fastest baud rates available consider the use of binary formats and use the continuous print mode Rev G E 4 JUNE 2012 POLHEMUS INNOVATION IN MoTION FASTRAK MANUAL APPENDIX F Cable Diagrams RS 232 Cable Diagram e IBM PC Compatible Computer e SGI O2 Onyx 2 or Octane To PC To FASTRAK D Type Connector D Type Conn 9 Pin Female 9 Pin Female Pin Identification Pin 1 2 Receive Data Transmit Data 3 3 Transmit Data Receive Data 2 4 8 5 Signal Ground 5 6 7 7 8 9 Rev G F 1 JUNE 2012 POLHEMUS INNOVATION IN MoTION FASTRAK MANUAL RS 232 Cable Diagram e IBM PC Compatible Computer To PC To FASTRAK D Type Connector D Type Conn 25 Pin Female 9 Pin Female Pin Identification Pin 1 2 Transmit Data Receive Data 2 3 Receive Data Transmit Data 3 ON UA E l 10 11 12 13 14 15 16 17 18 19 20 8 21 22 23 24 25 Rev G F 2 JUNE 2012 POLHEMUS INNOVATION IN MoTION FASTRAK MANUAL RS 232 Cable Diagram e SGI Indigo2 Indigo Onyx Iris To PC To FASTRAK Circular Connector D Type
84. le Fixed Metal Compensation Syntax Purpose Relatives Default Example Rev G d This command disables fixed metal compensation If a custom calibration has been performed by a Polhemus technician at the user location then issuing this command will disable the compensation offsets in the system outputs D The default condition is compensation disabled A system could be calibrated by Polhemus at a particular user location and then later moved to a different location where the calibration is no longer required The user should then disable the calibration that is no longer applicable This could be accomplished with the command d System measurements would no longer contain the compensation offset 44 JUNE 2012 POLHEMUS INNOVATION IN MoTION FASTRAK MANUAL e Define Stylus Button Function Syntax Purpose Default Relatives NOTE Rev G e station fbutton lt gt This command allows the user to put the FASTRAK stylus into different output modes by controlling the button function The command parameters are defined as station the number of a station fbutton defines the function of the stylus button An entry of fbutton 0 defines the output interaction as mouse mode The pushing of the stylus switch has no change on system output except that if the user has defined by use of the O Output Data List command page 57 an output with item 16 switch status the
85. le commercially Please contact Polhemus Customer Service see Contacting Polhemus Customer Service on page 8 should you need suggestions on where to locate these modules As with the RS 232 port the RS 422 transmit signals from the FASTRAK must be connected to the Host s Receive signals and the FASTRAK s Receive signals must be connected to the Host s Transmit signals Signal polarity conventions must be strictly observed See diagram below for connections RS 422 Cable Connections FASTRAK HOST RxB receive high pin 1 TxB transmit high TxB transmit high pin 4 RxB receive high RxA receive low pin 6 TxA transmit low TxA transmit low pin 9 RxA receive low 8 2 Powering Up FASTRAK To power up your FASTRAK system first ensure that the power switch on the back panel of the FASTRAK is in the off position and the power supply brick is not plugged into the AC wall Rev G 27 JUNE 2012 POLHEMUS INNOVATION IN MoTION FASTRAK MANUAL outlet Then connect the power cable from the power supply to the DIN power connector on the rear panel of the FASTRAK Connect the power cord to the power supply brick and plug it into the AC wall outlet Configure the dip switch settings on the I O select switch Plug in transmitter receivers and RS 232 cable and turn the power switch to the ON position On power up the power indicator will blink for several seco
86. lect Module Frequency Select Modules FSM Se FSM Frequency Select Modules s G Getting Started inse ro eere rg e rer ER e tua 1 WIOSSALY EE C 1 Rev G FASTRAK MANUAL H hemisphere Hemisphere ch Hemisphere of Operation eee 50 hemisphere tracking tenementis 50 Hemisphere Vector ere MS 15 V O Considerations essere 27 W O latency 5 nnne ege I O Select Switch en IBM PC Compatible Computer F 1 F 2 IEEE Floating Point Format eene 61 INCHES E ein P M Gemen e ette fep tec e eite Rer RE Initial Power Up Procedure Installing USB Device Drivers eee 29 Int rface RS 232 iinanenmiene noun eden 13 Interface USB enemies etii eene 13 Internal SynC s ert rtt eiii tp tie eden 3l Internal Sync Mode 83 L DD C 4 lige E E X ae 12 Latency White Paper QE li bility eeepc te tn eere ene we A 1 limited warranty limitation of liability we A 1 Line of Sight OS we CA line of sight iOS E 50 List of FIgures ericeira v Long Ranger Transmitter eee 26 LOS line of sight ceret rrr dientes LOS line of sight ES e p M M magnetic linkage sicco II AE E E inne e mi bien e Me
87. lected by the I O Select Switches on the back panel or as selected by the software command o see o Set Output Port on page 62 for full description Of course the USB interface can be utilized without concern for these limitations The FASTRAK default output record contains measurements for X Y Z in inches and Azimuth Elevation and Roll in degrees This output format can be easily modified by using O Output Data List on page 57 Although the FASTRAK offers a variety of output selections it is best to keep the output record length constrained only to the data that is needed Excessive data in the output record can slow down the transmission and not allow the system to output data to the host at the maximum update rate The FASTRAK contains an adaptive filter that is designed to control noise in the data output The filter can be applied to Position or Orientation or both and can be activated with simple commands that select low medium or heavy filtering It should be noted that the effect that is seen in the data may have or appear to have a slower dynamic response with medium or heavy filtering selected Rev G 33 JUNE 2012 POLHEMUS INNOVATION IN MoTION FASTRAK MANUAL 9 System Commands There are two classes of system commands one class for configuring the state of the system and the other for controlling its operation The commands are presented in functional alphabetical order
88. lus The tip offsets allow the tip to act as the measurement reference instead of the receiver coil inside the handle This command allows the user to override the factory defaults for the stylus tip offsets Although changing the tip offsets is not recommended the ability to do so is available The command parameters are listed below station 1 4 xoff x direction tip offset yoff y direction tip offset zoff z direction tip offset None Factory default tip offsets are read from the PROM inside the stylus connector on power up As a result the N command can only override the factory defaults during the current operational session If the user created a special stylus tip attachment that extended exactly one inch from the end of the stylus an adjustment to the tip offsets would have to be made To do so the following steps should be taken 1 Verify that the FASTRAK system is in inches unit measurement by sending the u command 2 Read the factory tip offsets from the PROM in the connector by sending the command N1 A typical factory tip offset might be 2 523 0 004 0 03 3 To add one inch to the factory calibration type N1 3 523 0 004 0 03 lt gt 4 To verify that the tip offset was entered correctly type N1 to read it back 56 JUNE 2012 POLHEMUS INNOVATION IN MoTION FASTRAK MANUAL O Output Data List Syntax Description Purpose Rev G Ostation p1 p2 pn Th
89. m of these samples yields the signal S component and the vector sum of the one sigma values of the deviation yields the noise N component The S N ratio may be expressed as a unitless number or in db that is 20 logio S N RESOLUTION Resolution for electromagnetic 6DOF measurement instruments is generally specified as angular resolution and translational resolution ANGULAR RESOLUTION Considering that the receiver is an all attitude 360 degree device the angular resolution is calculated by dividing 360 degrees by the S N ratio thus yielding its value in degrees TRANSLATIONAL RESOLUTION The translational or positional resolution is a function of the S N ratio and range Being a positional function there are three orthogonal vectors whose vector sum multiplied by any given range number yields the required translational resolution as shown in Figure D 3 One vector is defined along the axis of the range and is therefore a function of the inverse cube of the range The remaining two orthogonal vectors a amp b are a function of the tangent of the angle derived by dividing 180 degrees by the S N ratio Unlike angular resolution which uses 360 degrees divided by the S N ratio 180 degrees is used for these translational resolution component vectors because with an electromagnetic system there are two possible solutions to the 6DOF measurement problem This two solution possibility constitutes a potential system ambiguity Obviously fo
90. manufacturer s viewpoint accuracy is generally specified and or should be determined in a metallically clean environment The accuracy specified by manufacturers of electromagnetic 6DOF instruments is called Static Accuracy as the measurements are made with both the transmitter and receiver in a fixed and surveyed attitude and position condition within a specified motion box or field of regard POSITIONAL STATIC ACCURACY The positional Static Accuracy may be determined by measuring the vector positions CAT Y Z of a receiver positioned in a statistically valid number of fixed and known locations throughout a specified motion box using a precise mechanical positioning instrument with a precision gimbal The X Y and Z error terms are recorded and the RMS values calculated for each term These resulting error values one of X one for Y and one for Z are the system s positional Static Accuracy at each given point within the specified motion box Obviously an overall positional Static Accuracy for X Y and Z may be obtained by calculating the RMS value for all positional Static Accuracy points taken within the specified field of regard ORIENTATIONAL STATIC ACCURACY Whereas a similar exercise is required to determine the orientational Static Accuracy a clear understanding of the orientation parameters is necessary to understand the meaning of the specification and how it is measured The electrom
91. mapping procedure C 2 JUNE 2012 POLHEMUS INNOVATION IN MoTION FASTRAK MANUAL Direction Cosines EEPROM Elevation Factory Defaults Format Hemisphere Host Increment Rev G The cosines of the angles between the receiver s x y z axes and the X Y Z axes of the measurement reference alignment frame Electronically Erasable Programmable Read Only Memory Memory that can be altered by the 3SPACE but is not lost when the power is OFF User default data is stored here as well as the system identification data Coordinate of orientation tracking in the vertical plane where an increase in the angle is upward from the horizontal A term often substituted for elevation especially as it concerns flight is pitch The values assigned to certain system variables by the factory Stored in PROM they are used to reinitialize the variables if EEPROM is lost The interchange coding used to present data The 3SPACE outputs either ASCII or BINARY data but accepts only ASCII inputs from the host Because of the inversion symmetry of the magnetic fields generated by the transmitter there are two possible mathematical solutions for the X Y Z position coordinates for each set of receiver data processed and the 3SPACE is unable to determine which solution is the correct one without additional information Therefore only half of the total spatial sphere surrounding the transmitter can be utilized at any one time for una
92. mbiguous position measurement The selected hemisphere is referred to as the current hemisphere It is defined by an LOS line of sight vector from the transmitter through a point at the zenith of the hemisphere and is specified by the direction cosines of the chosen LOS vector The orientation coordinates do not have a two solution spherical ambiguity and are therefore valid throughout the operating sphere centered at the transmitter Any device capable of supporting an RS 232C interface or the high speed USB interface when available and capable of bi directional data transmission Devices may range from a dumb terminal to a mainframe computer The minimum movement necessary to cause the 3SPACE to transmit a record to the host C 3 JUNE 2012 POLHEMUS INNOVATION IN MoTION FASTRAK MANUAL I O latency Lag Line of Sight LOS LSB LSD MSB Motion Box Orientation Angles Rev G The interval of time needed by the host computer to transfer tracker data from the tracking system into the host application The total time from motion data sample capture to host inputting where the data are ready for application use 1 The orientation angle of the tracker receiver 2 In active tracker systems the angle between the source of stimulation and the tracker receiver 3 Not obscured or blocked from view such as a clear line of sight for optical uses Least significant bit Least significant digit Most si
93. me Field installation of a FSM should prompt user change out of the SEU color dot in order to facilitate easy identification among multiple FASTRAKs RS 232 Interface RS 232C serial port with software selectable baud rates of 1200 2400 4800 9600 19200 38400 57600 and 115200 ASCII or Binary formats The factory default setting is 115 2K baud An RS 422 port is available as an optional serial port in lieu of the RS 232 at the same baud rates USB Interface USB Universal Serial Bus has become the predominant interface standard It removes transmission speed limitations due to maximum baud rate and allows transmission speeds up to 12 Mbps USB utilizes differential signaling for better signal quality and noise rejection and therefore allows the use of longer communication cables between the host computer and the FASTRAK system Operating Environment Large metallic objects such as desks or cabinets located near the transmitter or receivers may adversely affect the performance of the system Many walls floors and ceilings also contain significant amounts of metal Operating Temperature 10 C to 40 C at a relative humidity of 10 to 95 non condensing Physical Characteristics e SEU Width 11 5 29 20 cm length 10 3 26 2 cm height 2 2 6 10 cm weight 3 0 Ib 1 40 Kg Rev G 13 JUNE 2012 POLHEMUS FASTRAK MANUAL INNOVATION IN MOTION e Transmitter Width 2 2 5 6 cm length 2 2 5 6 cm heigh
94. n the status of the switch is reported in the output record In this case a 1 is reported in the output record when the switch is pressed and a 0 when it is not pressed An entry of fbutton 1 defines a pseudo point or track mode interaction with the switch In non continuous mode of output pressing the stylus switch has the same effect as sending a P Single Data Record Output command page 63 to the system point mode In point mode every time the button is pressed a data record is sent to the host In continuous output mode pressing the stylus switch serves as a toggle for continuous output track mode The first time the button is pressed continuous output mode is turned off The next time the button is pressed continuous output mode is turned back on again and so on System default is fbutton 1 point and track mode stylus interaction None The stylus may be used as a receiver in any of the receiver ports However the button on the stylus will only work when the stylus is connected to Station 1 The stylus functions as a receiver with the electrical center offset from the tip of the stylus via software 45 JUNE 2012 POLHEMUS INNOVATION IN MoTION FASTRAK MANUAL F Enable ASCII Output Format Syntax Purpose Relatives Default Example Rev G F This command enables the ASCII output data format ASCII format means that the data is generally human readable while b
95. ncdcescebacecavededesssessdeaQheedousevooace 27 8 3 CONFIGURATION CHANGES oreet ete teo eso sosveodccescescssveusteecescesssenssesicesdevesssceveccsesssesstecessecersersoace 28 8 4 USING THE USB INTERFACE E 28 8 5 INSTALLING USB DEVICE DRIVERS cccccccccessesseceecceceesssaececececseseaaeeecececeeseaeeeeeeeesesenseaeeeeeceesenses 29 8 6 SYNCHRONIZATION ere Agen RES E Dedi obrero deeg exer ein Eie goce gie eeh 31 ST INTERNAL S LEE M E M 31 Rev G iii JUNE 2012 POLHEMUS INNOVATION IN MoTION FASTRAK MANUAL 8 8 EXTERNAL SYNC ccccccccccecsessssscecececeesesssseceeececesasececccecseeaaesecececeeseseeeseeeceesenaaeeecceeceeseaaeaeeeceeeenens 31 S9 VIDEO SYNG eege EE EE gegeer 32 8 10 MULTIPLE SYSTEMS OPERATION FASTRAKS PRODUCED AS OF JANUARY 2012 32 8 11 OUTPUT CONSIDERATIONS enne enennnnnn ennt net nh nnns sn en neni nsn si isst entera sa nsns esset teda nass sss n eaa 32 9 SYSTEM COMMANDS 34 9 1 COMMAND FORMAT NOTATION AND CONVENTION 34 9 2 COMMAND FORMAT Nos 9 3 COMMAND OUTPUT DC WEE A Alignment Reference Frame B Boresight b Unboresight KEE Continuous Output Mode e orte etit it ete ie ee eet o a E PESE VERE ES MER SEP eon re Disable Continuous Printing iii onere retine e Fd etie testi Dee e btt itio a tola eei bet bier ten dnd D Enable Fixed Metal C
96. nchronization pulse initiates magnetic field sampling a period that lasts about 3 5 ms It goes beyond the scope of this note to explain the sampling process in more detail so let it suffice that nine magnetic field samples are taken per cycle time The samples are then solved for receiver coordinates a period that requires another 2 ms The solution is then placed in an output buffer and is made ready for transmission over the interface in use The total sync to output latent period is the sum of field sampling and coordinate solution periods or 5 5 ms and is independent of update rate EFFECTIVE LATENT PERIOD Sync to output latency is important for reasons of interface timing however it does not quantify the effective latent period between receiver motion and output coordinate values If external synchronization and continuous print are not implemented the environment is being run asynchronously and the latent period cannot be defined precisely Rev G E 1 JUNE 2012 POLHEMUS INNOVATION IN MoTION FASTRAK MANUAL This period is important to helmet display or virtual reality applications since dynamic errors between the actual and computed coordinates can be very noticeable to the eye To discuss effective latent period let the beginning of the magnetic field sampling be at t 0 let the end of sampling be at t t and let the time that the solution appears in the output buffer be t T The computed solution for a rece
97. nds to indicate the system s performance of an initialization and self test routine During this time system operation is not possible At the completion of this routine the power indicator will change from a blink state to steady on which indicates that the system is now operational IMPORTANT NOTE Do not connect or disconnect the power cable to the FASTRAK while it is powered on or while the power supply brick is energized Internal component damage could result Initial Power Up Procedure Verify FASTRAK power switch is off Verify power supply brick is not energized plugged into the wall outlet Connect power cable from the brick to the power connector on rear panel of FASTRAK Plug power supply brick into AC wall outlet Configure switch settings on I O select switch Plug in transmitter receivers and RS 232 cable Turn on FASTRAK power switch 8 3 Configuration Changes Although receivers can be connected or disconnected while the unit is powered on it is not normal operating practice However if it is necessary to do this it is important to either cycle the system power or send the Y reset command This allows the device characterization data for the receiver to be read and applied to future measurements Normal system accuracy cannot be achieved unless the receiver characterization data has been read properly IMPORTANT NOTE Do not connect or disconnect the transmitter while the FASTRAK system is pow
98. nt cycle will start and thereby controls the tracking output from an application system point of view The FASTRAK system has three distinct synchronization modes that are controlled by the y Set Synchronization Mode commands page 83 and are defined as Command Synchronization Mode y0 lt gt Internal Sync Default yl lt gt External Sync y2 lt gt Video Sync 8 7 Internal Sync In the Internal Sync mode each measurement cycle of the FASTRAK system starts immediately after the previous cycle ends The system update rate is slightly greater than 120 Hz and cycle to cycle variations on the order of microseconds are possible in this mode Only the yO command is required to initiate the Internal Sync mode and no input is required for the system s SYNC IN port 8 8 External Sync The External Sync mode allows the user to define when the FASTRAK system measurement cycle will start by means of a user supplied external sync pulse This mode may be used to synchronize other peripheral instrumentation to the FASTRAK data collection cycle or to slow the FASTRAK to a known and desired rate To initiate the External Sync mode an external Rev G 31 JUNE 2012 POLHEMUS INNOVATION IN MoTION FASTRAK MANUAL signal as detailed in External Sync I O on page 17 must be input to the SYNC IN port and the yl command issued 8 9 Video Sync The Video Sync mode should be used when a receiver will be operating in close proximi
99. o The user can designate this receiver orientation as the zero orientation by sending the boresight command Bl lt gt This results in azimuth elevation and roll outputs of zero at this orientation As the subject s head moves away from the boresight point the orientation angles are still measured relative to the transmitter with the zero points shifted to the point where the boresight occurred 39 JUNE 2012 POLHEMUS INNOVATION IN MoTION FASTRAK MANUAL b Unboresight Syntax Purpose Relatives Example Rev G bstation lt gt This command removes the current boresight The system boresight rotation matrix is reset to the identity matrix for the specified station The command parameter is defined as station the number of the station to be boresighted B G If the user issued the B Boresight command page 39 while the receiver was at a particular orientation and then later decided that it would be best not to use a Boresight or there was a need to see what the system reads without the Boresight then the Unboresight command could be used as follows bl lt gt P the command to request a single data record could then be used to read the default orientation angles 40 JUNE 2012 POLHEMUS INNOVATION IN MoTION FASTRAK MANUAL C Continuous Output Mode Syntax C Description Output transmit mode refers to whether the system automatically transmits data P
100. o inconclusive results and lost effort in application measurements From the outset of electromagnetic 6 Degree Of Freedom 6DOF measurement technology regardless of the application the subjects of accuracy and resolution have been confusing in light of claims by competing technologies and product manufacturers This Application Note attempts to clarify accuracy and resolution and to illustrate their total applicability to the classical definitions THEORY OF OPERATION The position of a point in space may be fully described by its relationship to any fixed and convenient three axis x y Z coordinate system Orientation means direction in relationship to that position and may be fully described by three parameters or angles known as azimuth yaw elevation pitch and roll A typical Polhemus system consists of a fixed magnetic dipole transmitting antenna called a transmitter a freely movable magnetic dipole receiving antenna called a receiver and associated electronics as shown in Figure D 1 Both the transmitter and receiver antennas consist of three mutually orthogonal loops coils The loop diameters are kept very small compared to the distance separating the transmitter and receiver so that each loop may be regarded as a point or infinitesimal dipole Exciting a loop antenna produces a field consisting of a far field component and a near or induction field component The far field intensity is a function of loop size and excitation fre
101. o minimize the output resolution for static inputs while minimizing the output lag for dynamic inputs Whenever the input conditions cause the filter to make a transition to a narrower bandwidth i e increased filtering the transition rate of the pole location is constrained to a maximum allowable rate by the parameter FACTOR If all of the optional parameters are omitted the current value of each parameter is returned to the caller as an output record of type x None The default mode for all filter parameters is medium These settings may be used as a starting point for determining optimum filtering in your particular environment F 0 2 FLOW 0 2 FHIGH 0 8 FACTOR 0 95 Although they are already stored in the system EEPROM medium filtering can be selected by sending the following command to the system x 2 2 8 95 lt gt All active stations will now have medium filtering applied to the position measurements RECORD IDENTIFIER X INITIATING COMMAND X Rev G byte s Identification Format l Record type 2 Al Zu Blank Al Sas Sub record type x Al 4 10 Filter sensitivity bSx xxx 11 17 Floating filter low value bSx xxx 18 24 Floating filter high value bSx xxx 25 31 5 Transition rate maximum bSx xxx 32 33 Carriage return line feed 82 JUNE 2012 POLHEMUS INNOVATION IN MoTION FASTRAK MANUAL y Set Synchronization Mode Syntax Description Purpos
102. ommunication A system can be configured for RS 422 Rev G 19 JUNE 2012 POLHEMUS INNOVATION IN MoTION FASTRAK MANUAL or RS 232 communication but not both Once ordered a system can be returned to the factory to have its interface configuration changed for a nominal fee RS 422 is a differential transmit and receive I O standard with a maximum error free speed of 10 Megabits second technical specifications for RS 422 not FASTRAK with operation possible at a distance of 1200 meters with a speed of 100Kbits second The RS 422 does not use Handshake functions for transmission and reception The RS 422 transfer rate on a FASTRAK is the same as for RS 232 but larger communication cables can be used which is very important at higher baud rates The pinouts for this connector are as follow FASTRAK End User End TXB RxB Non inverting receive input 2 Not used 3 Not used 4 RXB TxB Non inverting transmit output 5 Not used 6 TXA EE RxA Inverting receive input 7 Not used 8 Not used 9 RxA TxA Inverting transmit output 7 11 Video Sync Input The Video Sync Input is a subminiature telephone receptacle that mates with the video pickup coil assembly Video Sync Detector optional The Video Sync Input is located on the rear of the SEU as shown in Figure 7 2 on page
103. ommunication determine system configuration check for BIT errors determine the firmware version number and read system identification information This command allows the operator to request a status record from the FASTRAK system T N A Sending the S command to the system will yield an output similar to the following where _ indicates a space 2aSfffbbb F3c j k lmxxxx e The fact that the status record was received verifies communication e 2isthe record type e ais the station number e Sisthe command e fff is the hex code for system configuration see following pages for explanation bbb is the BIT error code three spaces indicate no errors F3 is the ID tag is the map of present sensors j k Im is the firmware version number The remainder xxxx is system identification information that can be programmed by the operator using the X Configuration Control Data command page 80 NOTE The station listed is chosen by the FASTRAK depending on when the S command is sent during the cycle The user may have to issue this command several times in order to get the status data for a particular station RECORD IDENTIFIER S Rev G 68 JUNE 2012 POLHEMUS INNOVATION IN MOTION INITIATING COMMAND S byte s 1 2 3 4 6 7 9 10 11 12 13 14 15 16 21 22 53 54 55 Identification Record type EIR H Station number Sub record type S System f
104. ompensation d Disable Fixed Metal Compensapon nennen tet enne nne nennen 44 Ee Define Stylus Button P rction 52 inertem rene ELE E ree Re EO Eres end 45 F Enable ASCII Output Format P Enable Binary Output Format G Boresieht E H Hemisphere of Operation SR ENEE ge N Define Tip Offsets Or Output Data LAS tcd rte maerens no atraer er n eitis erc aree er System Data Record ASCI Format etit dise trim reete eL eit ETER E ESES eb E ARS SEOSTE siiis 59 System Data Record IEEE Floating Point Format 61 10 Set Output 62 P Single Data Record Output sty ci4 dscsccp desdceseconcuhsecsnasesteteiysidaisasnglasedi lt acatncanssbdecacepsaerala cededossigvaseatsicanesbnces 63 Q Angular Operational Envelope 2 0 ennt eie mire niei reor E irr Heer a Hire ens 64 KE Reset Alignment Reference Frame senectt rre ir i n Ra ERR a ERE MER KEEN RE REESE RE SEENEN 66 T Transmitter Mounting Et me iion roe Er EHE HER ERREUR ER XE rene as or eoe poda 67 S System Status Record ere ttr penetret enn e EY EIERENS EE SER PEE YER EEN Ee NES TESTS 68 T UE ENEE EE 70 Hi English Conversion Urs 5 0 minero pei i e Hae bre ee 72 TO Metric Conversion Units srair ns as E ERA EEEE EEE CERES UE EROR dE Eed 73 V Position Operational Envelope eg dree Ee eegene Er devsassobasied eb bn depen deus 74 v Attitude Filter Parame
105. on Measurements System Block Diagram D 2 PET UT CD di y E D 3 Figure Ee Translational Resolution eierlechen D 4 DUE TO SOFTWARE AND HARDWARE MODIFICATIONS SCREEN OR PRODUCT EXAMPLES APPEARING IN THIS MANUAL MAY VARY SLIGHTLY FROM THE ACTUAL SCREENS OR PRODUCTS THE USER ACCESSES Rev G v JUNE 2012 POLHEMUS FASTRAK MANUAL INNOVATION IN MOTION 1 Getting Started Congratulations on buying the finest 3D tracker system yet This section of the user manual has been provided to help get your project under way as quickly as possible There are two ways to get started with your FASTRAK system as with any new system You could wing it which involves a great deal of assumptions based on either previous experience and or visual inspection and hope for the best Alternatively you could sit down and read the whole manual line by line and then start What we provide here is a middle ground to cover the basics to get you going quickly However this approach does not preclude using the manual as a precise guide reference and final arbiter NOTE This approach assumes a single receiver use of the USB port communicating with a Windows PC and use of the FASTRAK Host Software Unpack the FASTRAK SEU transmitter receiver s and power supply Figure 1 1 Complete FASTRAK System 1 Set up the system close to your host computer and away from large metal objects like file cabine
106. ot permitted meaning that all active receivers operate at the same update rate i e one cannot be operated faster than another Active receivers are selected by physical receiver cable connections and software configuration commands Additionally the FASTRAK may be used with a stylus instead of a standard package receiver Tip offsets are automatically calculated for the stylus and no special commands are required for this mode of operation Switch functionality is provided with the stylus The stylus may be used in any of the Receiver Ports Operation of these devices is covered in Default Operation with a Stylus on page 90 Rev G 11 JUNE 2012 POLHEMUS INNOVATION IN MoTION FASTRAK MANUAL 6 Specification Position Coverage The system will provide the specified accuracy when standard receivers are located within 30 inches 76 cm of the standard transmitter Operation with separations up to 120 inches 305 cm is possible with reduced accuracy NOTE Alternative devices of larger smaller size are available as options and operate to longer shorter ranges Angular Coverage The receivers are all attitude Static Accuracy 0 03 0 08 cm RMS for the X Y or Z receiver position and 0 15 RMS for receiver orientation Resolution vs Range Resolution vs Range 2 000 1 1 800 1 600 4 1 400 1 200 1 000 Orientation Resolution inches degrees grecs PD Position 0 600 0 400 0 200 0 000 r 0 0 2
107. pose This command sets the distance unit to English or inches Subsequent input and output lengths will be interpreted as inches Relatives u Default The system default unit is inches Example Assuming the system units had already been changed to centimeters with the u command the following command could be sent to change back to inches U The system will now output data in inches and interpret input data in inches Rev G 72 JUNE 2012 POLHEMUS FASTRAK MANUAL INNOVATION IN MOTION u Metric Conversion Units Syntax Purpose Relatives Default Example Rev G u This command sets the distance unit to metric or centimeters Subsequent input and output lengths will be interpreted as centimeters U The system default unit is centimeters If the operator wanted the system to output its measurements in centimeters the following command should be sent u The system will now output data in centimeters 73 JUNE 2012 POLHEMUS INNOVATION IN MoTION FASTRAK MANUAL V Position Operational Envelope Syntax Vs xmax L ymax zmax xmin ymin zmin lt gt or Vs lt gt to read back the current limits Description The position operational envelope is an area defined by X Y Z minimum and maximum limits It provides the user with a means of specifying the location of the limits and notifies the user when the limits have been exceeded Purpose This command establis
108. quency and decreases with the inverse of the distance 1 r The induction field or quasi static field component intensity is not frequency dependent and decreases by the inverse cube of the distance 1 r The quasi static field is not detectable at long distances in fact its strength dominates at short distances and the far field is negligible Rev G D 1 JUNE 2012 POLHEMUS INNOVATION IN MoTION FASTRAK MANUAL MAGNETIC LINKAGE e aaa 3 Axis 3 Axis Field Field Source Sensor Detector Circuits Computer and Processing Software Position and Orientation Measurements x y 2 yaw pitch roll Figure D 1 Position and Orientation Measurements System Block Diagram In the system shown in Figure D 1 each loop of the transmitter antenna is in turn excited with a driving signal identical in frequency and phase Each excitation produces a single axis transmitter dipole The transmitter excitation is a pattern of three states Exciting the transmitter results in an output at the receiver of a set of three linearly independent vectors The three output receiver vectors contain sufficient information to determine the position and orientation of the receiver relative to the transmitter Essentially nine measurements are available to solve for the six unknowns of x y z for position and azimuth yaw elevation pitch and roll for orientation DEFINITIONS For resolution and accuracy considerations the electrom
109. r a position measurement only one solution is permitted and valid The units for translational resolution are either English inches or metric cm vector sum Range r Source Figure D 3 Translational Resolution Rev G D 4 JUNE 2012 POLHEMUS INNOVATION IN MoTION FASTRAK MANUAL ACCURACY The accuracy of electromagnetic 6DOF measurement instruments is a function of the error involved in making measurements and is therefore expressed in statistical error terminology It should be noted here that the use of statistical error terminology is the reason the accuracy of such instruments is generally specified in degrees RMS for attitude orientation and in inches or centimeters RMS for position As with resolution accuracy will be considered here from the point of view of the instruments as black boxes When treating the instruments as black boxes all classic error terms such as linearity repeatability hysteresis and drift are included One factor to be considered with any of the electromagnetic instruments is range or field of regard All instruments have a practical operating range for which accuracy is specified Operation beyond that range will degrade accuracy as a function of the degradation of the system s S N ratio Additionally all electromagnetic 6DOF systems are affected somewhat by the metallic environment in which they operate As this is clearly an uncontrollable function of the environment from the
110. r cable 7 4 Power Indicator A green LED power on indicator is located on the front of the SEU as shown in Figure 7 1 on page 15 Upon power up the indicator will blink for several seconds while the system performs its initialization and self test routines When these routines are complete the indicator changes from blink mode to steady on mode indicating that the system is ready for operation 7 5 VO Select Switch The I O Select Switch is an 8 position switch located on the rear panel of the SEU as shown in Figure 7 2 on page 15 and is only read on power up or system re initialization see Y Reinitialize System on page 88 The purpose of these switches is to select the RS 232 serial port parameters including baud rate character width and parity The modes with switch positions and their corresponding functions are as follows NOTE UP position is a logic 1 and DOWN is a logic 0 Switch Position Function 1 Baud rate select 2 Baud rate select 3 Baud rate select 4 Not used 5 Character width 0 7 bits 1 8 bits 6 Parity select 7 Parity select 8 I O Select UP for RS 232 The Baud rate select logic for switches 1 2 and 3 is as follows Again 1 Up and 0 Down Baud Rate 3 1200 2400 57600 115200 M e e 5 LE en E rn E en CH le Le E E rn rn E CIA 0 0 0 0 1 1 1 1 factory setting The system reads the baud rate switches only on power up or system re initialization Th
111. r pecelvers Figure 7 1 FASTRAK SEU Front View o PIN 1A0383 001 Freq a FASTRAK CE S N 407490030 Paus USB e SELI EXT SYNC power TT E E iy or o QD o 6 ow IN E wun Figure 7 2 FASTRAK SEU Rear View 7 2 Transmitter Port The single Transmitter receptacle port is a 15 pin male D type connector located on the front of the SEU as shown in Figure 7 1 The transmitter should be connected to the SEU before the unit is powered on and disconnected after the unit is powered off CAUTION Do not disconnect the transmitter while the FASTRAK SEU is powered on Also do not power on the SEU without a transmitter connected When routing cables please be sure the transmitter cable is routed separately from the receiver cables Rev G 15 JUNE 2012 POLHEMUS INNOVATION IN MoTION FASTRAK MANUAL 7 3 Receiver Ports 4 The four Receiver receptacle ports are 15 pin female D type connectors located on the front of the SEU as shown in Figure 7 1 The receiver s should be connected to the SEU before the unit is powered on and disconnected after the unit is powered off It is permissible to disconnect and re connect receivers while the SEU is powered on however it is necessary to send the Y Reinitialize System command page 88 after doing so This will allow the receiver s precise characterization matrix to be loaded into the FASTRAK memory Again rout the receiver cables separately from the transmitte
112. re tracking option is available but important criteria must be met in order for it to work properly see pages that follow for more information Identification of command parameters is as follows station the number of the station whose operational hemisphere is to be modified pl the x component of a vector pointing in the direction of the operational hemisphere Set to 0 to enable hemisphere tracking p2 the y component of a vector pointing in the direction of the operational hemisphere Set to 0 to enable hemisphere tracking p3 the z component of a vector pointing in the direction of the operational hemisphere Set to 0 to enable hemisphere tracking If all of the optional parameters are set to 0 then hemisphere tracking will be enabled for the specified station IMPORTANT NOTES ABOUT HEMISPHERE TRACKING Hemisphere tracking is a feature whereby the tracker can continuously modify its operating hemisphere given that it is started in a known valid hemisphere 1 When this command H1 0 0 0 lt gt is sent to the FASTRAK system the receiver of the specified station must be located in the currently set hemisphere 2 If the AK Save Operational Configuration command page 85 is sent to the FASTRAK system while hemisphere tracking is enabled the currently 50 JUNE 2012 POLHEMUS INNOVATION IN MoTION FASTRAK MANUAL Relatives Default Example 1 Example 2 Rev G computed hemi
113. references to medical or bio medical use are examples of what medical companies have done with the Products after obtaining all necessary or appropriate medical certifications The end user OEM VAR must comply with all pertinent FDA CE and all other regulatory requirements Rev G A 2 JUNE 2012 POLHEMUS INNOVATION IN MOTION FASTRAK MANUAL APPENDIX B Trouble Shooting Symptom FASTRAK Won t Communicate Possible Solution Check Dipswitch Settings Check RS 232 Cable Check Communication Program Settings Check PC COM Port Return SEU for Repair Green Light Won t Stop Flashing Download New Firmware Return SEU for Repair Solid Light Without Flashing First Return SEU for Repair BIT Error A C G I Return Transmitter for Repair Return SEU for Repair BIT Error a c BIT Error D F J L Change Tuning Module Move Transmitter Away From Metal Replace Power Supply Brick Return SEU for Repair Turn Off CRT Based Displays Separate Receivers Return Receiver for Repair Return SEU for Repair BIT Error T V Y Z Return Receiver for Repair Return SEU for Repair BIT Error U W X Return Transmitter for Repair Return SEU for Repair BIT Error d g Move Receivers Away From CRT Based Displays Separate Receivers Return Receiver for Repair BIT Error j l Return SEU for Repair BIT Error k Reduce Range Return Transmitter and or Receiver for Repair BIT Error m x y Peform Followin
114. rmation Set Unit Inches Metric Conversion Units Position Operational Envelope Attitude Filter Parameters Reset System to Defaults Configuration Control Data Position Filter Parameters Set Synchronization Mode Save Operational Configuration Resume Data Transmission Suspend Data Transmission Re initialize System FASTRAK MANUAL Brief Description Defines reference frame and origin Sets AER to zero or the value set by G Removes new reference set by B Enables continuous data output Disables continuous data output Turns on compensation if applicable Turns off compensation if applicable Modifies stylus button function Enables ASCII output format Enables binary output format Allows B to yield specific AER output Defines operating side of transmitter Control output by receiver movement Turns a receiver station off or on Modifies stylus tip offsets Changes data output list Modifies output port parameters Requests a single data output record Sets angular operational envelope Clears previous alignment for new entry Modifies transmitter mounting frame Requests a system status record Clears BIT error and obtains more info Sets XYZ measurements to inches Sets XYZ measurements to centimeters Sets XYZ operational envelope Modifies AER filter parameters Resets EEPROM to default settings Modifies configuration data in status record Modifies the XYZ filter parameters Modifies sync mode Saves current configuration to EEPROM Allow
115. rs the tracker will output nothing until this receiver is again processed Another common problem is the RS232 communications XON XOFF protocol If the user s computer cannot assimilate the tracker s output fast enough the computer can transmit an XOFF signal to the tracker commanding it to stop transmitting When the user s computer has finally assimilated the data it has accumulated it transmits an XON command and the tracker once again begins transmitting coordinate data During the XOFF period the tracker s output buffer is continually discarding solutions to prevent buffer overflow thus many data sets are never transmitted Toggling of XON XOFF in the user s computer could be happening without the user s knowledge and could again make it appear that tracker sync to output latent period was varying from 5 5 ms to many times this and periodically dropping data The RS232 lines should be monitored if this problem is suspected A third problem is asynchronous interfacing and a particularly annoying example of such an interface is MIL STD 1553 as this bus is not only asynchronous but often very slow e g 25 Hz Asynchronous interfaces guarantee that on the average the apparent latent period will be increased by one half the tracker cycle time For a slow 25 Hz bus rate the sync to output latent period would vary from 5 5 ms to 13 8 ms Another example is a unsynchronized computer issuing single record print commands at random times in
116. s data to be transmitted Restricts data from being transmitted Invokes start up as if power was cycled 10 JUNE 2012 POLHEMUS INNOVATION IN MoTION FASTRAK MANUAL 5 Technical Overview The FASTRAK tracking system uses electro magnetic fields to determine the position and orientation of a remote object The technology is based on generating near field low frequency magnetic field vectors from a single assembly of three concentric stationary antennas called a transmitter and detecting the field vectors with a single assembly of three concentric remote sensing antennas called a receiver The sensed signals are input to a mathematical algorithm that computes the receiver s position and orientation relative to the transmitter The FASTRAK consists of a System Electronics Unit SEU one to four receivers a single transmitter a power supply and a power cord The system is capable of operating at any of four discrete carrier frequencies Different carrier frequencies allow operation of up to four FASTRAKs simultaneously and in close proximity to one another The FASTRAK interfaces to the host computer via RS 232 and USB serial communication Any single receiver may be operated at the fastest update rate 120 Hz any two receivers at one half this rate any three at one third this rate or all four at one fourth the fastest rate Of course the unit must be set to output at a high enough baud rate to receive these updates Mixed rates are n
117. s produce light filtering in the limit as a 0 the filter output never changes and in the limit as o 1 the output exactly follows the input The filter parameter o can be set to a specific value through system commands or a range of values can be specified which allows the system to choose its own optimum value automatically adapting to environmental noise Equation E 2 expresses the steady state filter response for zero acceleration in receiver coordinates and for a constant filter parameter a In the derivation of the equation the 129 E 66 99 coordinate x is assumed to be of the general form x vt where v represents a constant velocity in either position or orientation t is time and At is the tracker s cycle time the inverse of update rate de esce Eras a Equation E 2 Equation E 2 can be reformulated to express the filter time delay for a constant rate of change v in input eL m v a Equation E 3 Rev G E 3 JUNE 2012 POLHEMUS INNOVATION IN MoTION FASTRAK MANUAL Equation E 3 may be interpreted as the error in degrees per v degrees second in orientation input or the error in inches per v inches second of translation Note that in either case the units are in seconds As an example suppose that the update rate of the tracker is 120 Hz thus At 1 120 second Suppose also that the receiver is slewing in azimuth at 90 degrees per second and that o is a constant 0 95 a value
118. sphere will be saved not the hemisphere tracking feature to the EEPROM Therefore sending K during hemisphere tracking is not advised None The default hemisphere value is 1 0 0 which is positive X or forward hemisphere In addition the hemisphere tracking feature is disabled in the default condition The user may decide to mount the transmitter above the test area in order to be able to move the receiver to the positive and negative sides of X and the positive and negative sides of Y NOTE since the default hemisphere value is forward the user cannot move the receiver to the negative X side of the transmitter because the signs will flip and it will appear as if the X measurement never goes negative If the transmitter is positioned above the test area the positive Z or lower hemisphere should be selected This can be accomplished with the following command H1 0 0 1 lt gt Station 1 of the FASTRAK will now be set for the positive Z or lower hemisphere Although the hemisphere vector is not limited to 1s and Os the following table of hemisphere commands may be useful Forward Hemisphere X H1 1 0 0 lt gt Back Hemisphere X H1 1 0 0 lt gt Right Hemisphere Y H1 0 1 0 lt gt Left Hemisphere Y H1 0 1 0 lt gt Lower Hemisphere Z H1 0 0 1 lt gt Upper Hemisphere Z H1 0 0 1 The user may decide to take advantage of the hemisphere tracking feature Assuming the system is
119. station off A user could connect four receivers to a FASTRAK and then collect a data point from two receivers at a time after disabling the other two To do so the following commands would be sent Send the command 13 0 lt gt to turn station 3 off Send the command 14 0 lt gt to turn station 4 off Press P to collect a data point from stations 1 and 2 Send the command 13 1 lt gt to turn station 3 on Send the command 14 1 lt gt to turn station 4 on Send the command 11 0 lt gt to turn station 1 off Send the command 12 0 lt gt to turn station 2 off Press P to collect a data point from stations 3 and 4 Repeat steps 1 through 8 as necessary SUP Bm pce M 54 JUNE 2012 POLHEMUS INNOVATION IN MoTION FASTRAK MANUAL byte s Identification Format las Record type 2 Al 2 un Station number AI 3 uas Sub record type T Al A ER Station 1 1 if active elseO Al Sau Station 2 1 if active elseO Al 6 Station 3 1 if active elseO Al Tuus Station 4 1 if active elseO Al 8 9 Carriage return line feed Rev G 55 JUNE 2012 POLHEMUS INNOVATION IN MoTION FASTRAK MANUAL N Define Tip Offsets Syntax Description Purpose Relatives Default Example Rev G Nstation xoff yoff zoff lt gt or Nstation lt gt to read back the current tip offsets Each stylus has been factory calibrated with custom tip offsets This is the offset of the receiver from the tip of the sty
120. stem or an external sync source Note This setting can not be saved to EEPROM with the R command 2 Video Sync Mode Signifies that the system is synced via a video frequency pickup coil None 0 Internal Sync Mode If the user had a requirement to operate two FASTRAK systems in relatively close proximity the following steps should be taken 83 JUNE 2012 POLHEMUS INNOVATION IN MoTION FASTRAK MANUAL 1 Designate one FASTRAK system as the master and the other as the slave NOTE Make sure that the two FASTRAKs have different colored dots on them so you will know that they are operating at different frequencies 2 Connect one end of the sync cable to the sync out receptacle of the master FASTRAK 3 Connect the other end of the sync cable to the sync in receptacle of the slave FASTRAK 4 Send the command y0 lt gt to the master FASTRAK 5 Send the command yl lt gt to the slave FASTRAK The two systems will now be synced together NOTE Although synchronization allows two FASTRAKs to operate in relatively close proximity make sure the receiver of one system does not get closer to the transmitter of the other system than it is to the transmitter of its own system See Multiple Systems page 32 for multiple systems synchronization RECORD IDENTIFIER y byte s Identification Format lags Record type 2 Al d s Blank Al dde Sub record type y Al 8 us Synchronization mode Il 0 non
121. t 2 3 5 8 cm weight 0 6 Ib 0 27 Kg excluding attached cable The Transmitter may be purchased with either 10 or 20 cables e Receiver Width 1 1 2 83 cm length 0 90 2 29 cm height 0 60 1 52 cm weight 0 6 oz 17 0 gm excluding attached cable Receivers may be purchased with either 10 or 20 cables Stylus Length 7 00 17 78 cm including tip or the shorter version Stylus length 3 5 6 04 cm maximum barrel diameter 0 75 1 9 cm handle diameter 0 375 0 95 cm tip length 0 8 2 03 cm tip diameter 0 156 0 4 cm weight 2 5 oz 28 3 gm excluding attached cable Either stylus may be purchased with either 10 or 20 cables Power Requirements International Power Sources Supply Input power is 100 240 VAC 47 63 Hz and single phase at 15 watts Rev G 14 JUNE 2012 POLHEMUS FASTRAK MANUAL INNOVATION IN MOTION 7 Component Description 7 1 SEU The System Electronics Unit SEU is a stand alone unit that may be located anywhere that is convenient to the work area AC power and the host computer It contains the required input and output connectors and controls to support up to four receivers a single transmitter and the RS 232 and USB output ports Receiver Input s Transmitter Input I O Cables I O Select Switch External Sync I O Video Sync Input and Power Input connections are located on the SEU as shown in Figure 7 1 and Figure 7 2 below pA Ug UI D s one M tt
122. t Modules e Separation distance should be 23 feet or 7 meters If systems have different Frequency Select Modules e Separation distance should be 15 inches or 38 centimeters with transmitter to transmitter adjacent spacing no closer than 6 inches or 15 2 centimeters Again separation distance is defined as the distance between the transmitter of one system and the receiver of another system NOTE These separation distances assume FASTRAK systems using standard 2 inch transmitters and standard receivers 8 11 Output Considerations Most applications of the FASTRAK system involve using its data output to manipulate some type of computer graphics in real time In this condition it is extremely important to allow the data to be utilized as quickly as possible and to avoid latency or lag Lag is defined as the interval of time between requesting a tracker data point and receiving it into the host computer Factors that could increase this lag are e Baud Rate e Output Record Length Rev G 32 JUNE 2012 POLHEMUS INNOVATION IN MoTION FASTRAK MANUAL e Data Format binary is more efficient than ASCID e Filtering The FASTRAK baud rate should be set to the highest setting that is compatible with the host computer and the communication software Although the FASTRAK system runs at 120 Hz it may appear that it is running slower if the output is constrained by a slow baud rate The FASTRAK is capable of running at speeds of up to 115 200 as se
123. te value Minimum x coordinate value Minimum y coordinate value Minimum z coordinate value Carriage return line feed 75 FASTRAK MANUAL Format AI AI AI SXXX XXX SXXX XXX SXXX XXX SXXX XXX SXXX XXX SXXX XXX JUNE 2012 POLHEMUS INNOVATION IN MOTION FASTRAK MANUAL vy Attitude Filter Parameters Syntax Purpose Rev G v F FLOW FHIGH FACTOR lt gt or v n Macro filter command or v lt gt to return the current filter values selected This command establishes the sensitivity boundary and transition control parameters for the adaptive filter that operates on the attitude outputs of the tracking system The user can adjust the parameters of this command to fine tune the overall dynamic response of the tracker F FLOW FHIGH FACTOR a scalar value that establishes the sensitivity of the filter to dynamic input conditions by specifying the proportion of new input data to recent average data that is to be used in updating the floating filter parameter variable Allowable range of values 0 lt F lt 1 a scalar value that specifies the maximum allowable filtering to be applied to the outputs during periods of relatively static input conditions Setting this value to 1 0 disables the filter completely Allowable range of values 0 lt FLOW lt FHIGH or 1 0 to disable filter a scalar value that specifies the minimum allowable filtering to be applied to the outputs
124. ted R times S is the sign byte either or space for X isa decimal digit 0 9 is a decimal point B isablank H isahexadecimal digit 0 F Example A format 3 Sx xxxxB would be output as 1 1111 2 2222 3 3333 e For discussion purposes all Examples assume only 1 receiver is used connected to the station receptacle Rev G 35 JUNE 2012 POLHEMUS INNOVATION IN MOTION FASTRAK MANUAL 9 3 Command Output Listing See pages that follow NOTE Any command with a next to it means that it cannot be stored in EEPROM i e if a AK Save Operational Configuration command see page 85 is executed the information will not be saved after the system power is turned off ALIGNMENT REFERENCE FRAME TRANSMITTER REFERENCE FRAME Xx Xy Xz ORIGIN Ox Oy 0z TRANSMITTER Figure 9 1 System Alignment Rev G 36 JUNE 2012 POLHEMUS INNOVATION IN MoTION FASTRAK MANUAL A Alignment Reference Frame Syntax Purpose Relatives Range Default Example Rev G Astation Ox Oy Oz Xx Xy Xz Yx Yy z lt gt or Astation lt gt to read back the current alignment The alignment command does two things It defines a reference frame to which all position and orientation output data is referred In addition it creates a new origin point where the X Y Z measurements would equal 0 0 0 if the receiver were placed there Se
125. ted and found to comply with the limits for a Class A digital device pursuant to part 15 of the FCC Rules These limits are designed to provide reasonable protection against interference when the equipment is operated in a commercial environment This equipment generates uses and can radiate radio frequency energy and if not installed and used in accordance with the instruction manual may cause interference to radio communications Operation of this equipment in a residential area is likely to cause interference in which case the user will be required to correct the interference at the user s expense EC Declaration of Incorporation For all FASTRAK models produced as of January 2012 this product conforms to the following European Community Directives EMC Directive 2004 108 EC LVD 2006 95 EC The following standards were used to verify compliance with the directives EMC EN 61326 1 2006 EMC requirements Class A Emissions Class A Harmonics EN 55011 1998 A1 1999 A2 2002 Radiated amp Conducted Emissions NOTE The conducted emission here in only applies if a Polhemus supplied power supply is used with the FASTRAK electronics unit N 61000 3 2 2000 Harmonics N 61000 3 3 1995 A1 2001 Flicker N 61000 4 2 1995 A1 1998 A2 2001 ESD N 61000 4 3 2002 Radiated RF Immunity N 61000 4 4 2004 Electrical Fast Transient Burst N 61000 4 5 1995 Surge Immunity N 61000 4 6 1996 Conducted RF Immunity E E E E E E E EN 61000 4 11
126. terms are recorded and the RMS values calculated for each term The resulting error values one for azimuth one for elevation and one for roll are the instrument s orientational Static Accuracy As for the positional Static Accuracy the overall orientational Static Accuracy for azimuth elevation and roll may be obtained by calculating the RMS value for all orientational Static Accuracy points taken within the specified field of regard CONCLUSION It can be seen from the above discussions that accuracy and resolution for electromagnetic 6DOF instruments conform to the classical definitions of these terms Accuracy is indeed the fractional error obtained in making a measurement and Resolution is the granularity of the measurement or the smallest amount of the quantity being measured that the instrument will detect It can also be seen that numerical values of accuracy and resolution may be obtained from careful and precise measurements of the system s output data with respect to surveyed and known receiver positions and orientations Rev G D 6 JUNE 2012 POLHEMUS INNOVATION IN MoTION FASTRAK MANUAL APPENDIX E Latency White Paper TECHNICAL NOTE Latency 3SPACE FASTRAK H R Jones INTRODUCTION ANSI TEEE Std 100 1977 defines latent period as The time elapsing between the application of a stimulus and the first indication of a response The definition excludes the time required to transmit the response It is in
127. ters W Reset System t D faults 5 neenon p rei P E HR HEIL PR ER Or PEE HELLE FE erts ene es 79 X Configuration Control RE iie ertet em inet t eR Eee re E voce o ern redeo peas 80 x Position Filter Parameters fy Set Synchronization Mode perte d ted eei pd e Ie cava Col iet Ee deep ek oun 83 AK Save Operational Configuratin pedir tre t re er pe ER p b iae deiei 85 AQ Resume Data Transmission S Suspend Data Transmission WY Remitialize System iieri etie Pei bep ERR Ee eerte Pei deer debeo EEES TERES 10 COMMAND ERROR 11 DEFAULT OPERATION WITH A STYLUS 4 eeeeeeee eese eese ense tn seta etta sts stessa sss to setas sense ta 90 APPENDIX A Limited Warranty and Limitation of Liabltw neret A 1 APPENDIX B Trouble ShoOlg oct ee CS o E OR EN NOI tg Ld eei I oU en B 1 APPENDIX C Gl s88aty E C 1 APPENDIX D Accuracy and Resolution White Paper ccccceecseseeecceseesecesecseceeceaeceeesecseeeseesecesecseeeaeeeeneeeaeees D 1 APPENDIX E Latency White Paper eese ce eene et ette eren ape vea onse a Sena ea e EE EN ERAS e NER RYE EE Fe aee eR EE E 1 APPENDIX F Cable Diagrams Rev G iv JUNE 2012 POLHEMUS INNOVATION IN MoTION FASTRAK MANUAL List of Figures Figure 1 1 Complete FASTRAK System e EGRE n etn deeded Se een DUDEN 1 Figure 1 2 Transmitter Connection EN 2 Figure l 3 Receiver E 2 Figure 1 4 Mounting Transmi
128. that can be attained by either fixing both the upper and lower limits of a to 0 95 or by setting just the upper limit to 0 95 and letting the adaptive filter push a to this maximum limit which is what would happen for slew rates of this magnitude The filter lag for this example is calculated to be 0 44 ms The correct interpretation of this figure is that the receiver coordinates output at t 5 5 ms correspond to where the receiver was at t 1 2 0 44 ms 2 2 ms this would increase apparent latency to T 7 2 0 43 ms 4 2 ms The next example demonstrates what can happen when the filter constant is set too low producing extremely heavy filtering Suppose a is set to 0 05 and all other conditions are the same as in the above example In this case the filter lag calculates to 158 ms and the interpretation is that the coordinates output at t 5 5 ms corresponds to where the receiver was at t 1 2 158 ms this yields an apparent latent period of T t 2 158 162 ms Obviously low filter settings must be avoided if any reasonable dynamic response is desired RECAPPING This technical note has discussed the latency in the application of a Polhemus 3SPACE FASTRAK product As pointed out sync to output and effective latencies are measures of tracker throughput and cannot be changed while apparent latency and filter response are controlled to a degree by the interface and application environment To derive best performance the FASTRAK product shou
129. the PiMgr window This will cause PiMgr to request a single data frame from the FASTRAK system The contents of the frame will be displayed in the text window at the top of the PiMgr display The airplane image s in the graphics portion of the screen will move to the retrieved position and orientation Figure 1 10 FASTRAK Data Record Display 9 At this point you may turn on the FASTRAK using the power switch located on the back panel of the SEU Note the power on indicator located on the front panel of the electronics unit It should flash for approximately 10 seconds indicating self test and set Rev G 6 JUNE 2012 POLHEMUS 10 11 12 13 14 INNOVATION IN MoTION FASTRAK MANUAL up When these routines are completed after the flashing the indicator will turn to a steady on state thereby indicating that the system is ready to operate You may now use the PiMgr to exercise the system After clicking a single button or sending a P Single Data Record Output command see page 63 to the system the 6 Degree Of Freedom 6DOF output data will be sent to the host The data consists of a header Os where s equals the station number and six columns of data as follows NOTE These values represent an arbitrary placement of the receiver and transmitter 1 2 3 4 5 6 7 01 16 08 0 38 0 71 3 005 1 12 0 67 FASTRAK Data Record Column Function 01 Header not shown above X position in
130. this context that we define the latent periods 1 between the application of a synchronization pulse and a response and 2 between the application of receiver motion and a response The response for both cases occurs when the receiver coordinate solution is made ready for output and as noted above does not include the time required to transmit the coordinates over the interface in use e g RS 232 MIL STD 1553 IEEE 488 etc Polhemus 3SPACE FASTRAK magnetic 6DOF measurement systems emanate low frequency magnetic fields from a stationary transmitting antenna and sense them with a movable receiving antenna The received magnetic field samples are subjected to analog and digital processes and are ultimately solved for the receiver s position and orientation coordinates The solutions are formatted in varied ways according to user selections then output over various types of interfaces depending on the product The FASTRAK system s latent period is due to the time required to sample the magnetic fields solve for the receiver coordinates and make the solutions available for output However from the user s point of view the latent period may appear longer than this due to delays in the interface or in the user s computer or due to incorrectly configured FASTRAK filters which can make the response appear to occur later These topics are discussed in the following paragraphs SYNC TO OUTPUT LATENT PERIOD Application of an external sy
131. ting frame Purpose This command allows the user to modify the mounting frame coordinates of the transmitter relative to a particular receiver It is basically a non physical rotation of the transmitter and becomes the new orientation reference for the specified receiver s measurements The command parameters are as follows station the station to be defined A azimuth mounting frame angle E elevation mounting frame angle R roll mounting frame angle Relatives None Default 0 0 0 Example If there was a requirement to mount the transmitter upside down more mechanically feasible then the following command should be used r1 0 0 180 lt gt The orientation measurements for station 1 will now look as if the transmitter had not been mounted upside down RECORD IDENTIFIER r INITIATING COMMAND r byte s Identification Format Ts Record type 2 Al os Station Number Al 3 Sub record type r Al 4 11 Azimuth mounting frame angle SXXX XXX 12 19 Elevation mounting frame angle SXXX XXX 20 27 Roll mounting frame angle SXXX XXX 28 29 Carriage return line feed Rev G 67 JUNE 2012 POLHEMUS INNOVATION IN MoTION FASTRAK MANUAL S System Status Record Syntax Description Purpose Relatives Default Example S Status refers to the capability to determine information about the system that is not available from other commands This command allows the operator to verify c
132. top the data stream to adjust other system parameters This can be accomplished by sending the command c The continuous data output mode will be disabled and the data stream will stop 42 JUNE 2012 POLHEMUS INNOVATION IN MoTION FASTRAK MANUAL D Enable Fixed Metal Compensation Syntax D Description Compensation refers to programmed offsets that allow system computations to be Purpose Relatives Default Example Rev G accurate while the system is used in an environment containing metal within close proximity of the transmitter and receiver Generating compensation requires the use of special fixtures and proprietary software and is usually performed by a Polhemus technician This command is used to turn on compensation offsets If a custom calibration has not been performed by a Polhemus technician at the user location then enabling this command will yield no change in the system outputs D d The default condition is compensation disabled In most cases the user is able to locate a test set up where compensation is not required If it is required and Polhemus is contracted to perform a calibration then the system will be left with compensation enabled The command to enable compensation on all active stations is simply D The compensation offsets will now be applied to all position and orientation measurements 43 JUNE 2012 POLHEMUS INNOVATION IN MoTION FASTRAK MANUAL d Disab
133. tric Conversion Units Mini RECEIVER RR Motion BOX ire mounting frame uj n JUNE 2012 POLHEMUS INNOVATION IN MoTION FASTRAK MANUAL O Ir EE 11 13 16 18 27 90 RS 232 Cable Connections eee 27 Operating Environment RS 232 Cable Diagram Operating Temperature bus IBM PC Compatible Computer F 1 F 2 Optional RS 422 HO SGI 02 Onyx 2 or Oetane eeeeeeceeseeseeeeseeeseetenee F 1 orientation angles SGI Indigo2 Indigo Onyx Iris F 3 Orientation Angles SGI VTX Onyx Personal Iris orientational static accuracy RS 232 communication RS 232 I O RS 232 Interface separation distance eese ee set conversion units PIC ecce nete ona endete meiden C 6 Set Output Port center nito Position and Orientation Measurement D 2 Set Synchronization Mode sss Position Coverage ssiri tinsi eee enn SEU Position Filter Parameter SEU System Electronics Unit Position Operational Envelope SEU Systems Electronics Unit ssssss 11 positional static accuracy c ceceecesesessseseseeteeeeetseeesesesees SGI 02 Onyx 2 or Octane seen F 1 Power Indicator eee SGI Indigo2 Indigo Onyx Is F 3 Power Input s SGI VTX Onyx Personal Iris ssesees F 4 Power Input Receptacle ees
134. ts metal desks etc and away from the floor and walls 2 Identify the transmitter the two inch gray cube or the four inch black cube and insert the transmitter connector into the transmitter receptacle being careful to firmly engage it Using your fingers or a small flat blade screwdriver lock the connector by tightening the two retaining screws Rev G 1 JUNE 2012 POLHEMUS INNOVATION IN MoTION FASTRAK MANUAL Figure 1 2 Transmitter Connection 3 For getting started use only one receiver Identify the receiver and insert it into the receiver receptacle labeled one as shown below Firmly engage and lock the receiver connector into place in the same manner as the transmitter connector in Step 2 Figure 1 3 Receiver Connection 4 For testing purposes it is convenient to mount both the transmitter and the receiver on a single block of wood 2X4 or equivalent about 16 inches apart Exact placement of the transmitter and receiver is not important for this test just make sure the cables of both devices are not routed together and they come off opposite ends of the 2X4 Figure 1 4 Mounting Transmitter and Receiver on 2x4 Rev G 2 JUNE 2012 POLHEMUS INNOVATION IN MoTION FASTRAK MANUAL 5 Identify the five pin DIN type power input connector on the back panel of the electronics unit Figure 1 5 Power Connector With the separate Power Supply brick UNPLUGGED from the outlet of the wall plug
135. tter and Receiver on Zu 2 Figure 1 5 Power EN 3 Figure 1 6 DC Power Cable Installaflol esceseneaeet svudtueed edic Cau bei ba ch euve doa ra paa FON daga DEMON 3 Figure 1 7 DC USB Cable Installation ae tei dies ia En pup Ka be lisa ode an Ire cu AMEN Pda E 4 Figure 1 8 PiMgr Screen REH a Figure 1 9 E 6 Figure 1 10 FASTRAK Data Record Display eese eee eeeeeee eee nennen nn antennas setti 6 Figure 7 1 FASTRAK SEU Front E 15 Figure 7 2 FASTRAK SEU Rear VIEW ausus pte ia sedadc a pnt EE QRP ATA RNV E ERR Rd a M Ei Hn EEUU RE a EE 15 Figure 7 3 Default I O Select Dip Switch Settings eese eee niea eee aa eain aaa stanno a atas nasi span 17 Figure 7 4 Sync Connector Identification Input and Output essere 18 Figure 7 5 RS 232 Cable COMM CH OM NETTE 19 Figure 7 6 Transmitter HG PHA eins Ee uA ANDA ERR eege MA ERU RE 21 Figure AMD 10i a RN 21 Figure 7 8 RX2 Receiver Dimensions in Inches eee eese ee eeeee nennen nente than 22 Figure 7 9 RX1 D Receiver in inches o iaidacecva dte xda indo pcvsi eve dada Dix vend Ap tuu asi quld waste nbi LE EL IDU 23 TPE 7 10 Receiver E TERR 23 Figure 7 11 Stylus EIERE enee Pete P nd tA du Ruhe 25 Figure Eeer 25 Figure 7 14 Video Sync Detector gege ees 26 Figure 8 1 Connection of USB Cable to Switch to USB Mode 29 ee 36 Figure 9 2 Hemisphere E 32 Fig re sp Fuler Angles sirsrcsoiroconistiaore ao AEE R S RR EE E T E C 5 Figure E 1 Position and Orientati
136. ty to a CRT monitor and the FASTRAK measurements appear noisy The amount of noise detected will ultimately determine the definition of close proximity but it is usually when the receiver is less than 24 inches away from the monitor The reason this can occur is that all CRT monitors produce a magnetic field during the vertical refresh cycle After connecting the video sync detector and sending the y2 command the detector will sense the magnetic field and cause the FASTRAK to begin each measurement cycle after a slight pause for settling time This ensures that the FASTRAK measurement cycle will not occur during the monitor refresh cycle and eliminate noisy data 8 10 Multiple Systems Operation FASTRAKS produced as of January 2012 When using more than one FASTRAK in the same area it is important to ensure that each unit have a different Frequency Select Module NOTE Separation distance is defined as the distance between the transmitter of one system and the receiver of another system when both systems are operating Without changing the frequency module the minimum separation distance is 23 feet or 7 meters If the Frequency Select Modules are different then the minimum separation distance is 15 inches or 38 centimeters Clearly the latter option offers the greatest set up flexibility and user freedom The separation distance guidelines are restated below for further clarification If systems have identical Frequency Selec
137. ud rate 19 200 in order for communication with the system to continue 62 JUNE 2012 POLHEMUS INNOVATION IN MoTION FASTRAK MANUAL P Single Data Record Output Syntax P Description Output transmit mode refers to whether the system automatically transmits data Purpose Relatives Default Example Rev G records to the host continuous output mode or the host must request data records by sending a command to the system each time non continuous output mode In non continuous output mode this command requests a single data record to be transmitted to the host If more than one station is enabled then data from each active station will be displayed in numerical order station 1 first station 2 second etc That is a complete cycle of active stations will be output Cie Continuous output mode is disabled If the system is being used in an application where data is only needed a certain number of times then the single data record output should be used To request a single data record from the system send the command as follows P One data record from the FASTRAK system will be sent across the serial port to the host computer 63 JUNE 2012 POLHEMUS INNOVATION IN MoTION FASTRAK MANUAL Q Angular Operational Envelope Syntax Purpose Relatives Default Example Qs azmax elmax rlmax azmin elmin rlmin lt gt or Qs lt gt to read back the current orientat
138. urpose Relatives Default Example Rev G records to the host continuous mode or the host must request data records by sending a command to the system each time non continuous mode This command enables the continuous print output mode When the system is in continuous mode the data points from all stations are requested automatically and are scrolled one after the other in a continuous stream If more than one station is enabled then the data from each station will be displayed in numerical order station 1 first station 2 second etc GP Continuous output mode is disabled If the system is being used in an application where a fast update rate is critical driving real time computer graphics e g an animated character then the continuous output configuration should be enabled To enable continuous output mode send the command as follows C Data from the FASTRAK will now scroll continuously across the serial port to the host computer 41 JUNE 2012 POLHEMUS FASTRAK MANUAL INNOVATION IN MOTION c Disable Continuous Printing Syntax Purpose Relatives Default Example Rev G c This command disables the continuous print output mode After sending this command the continuous data stream from the FASTRAK to the host computer will stop C P Continuous output mode is disabled If the system is set to continuous output mode with the C command the user may wish to s
139. ve the receiver along the proposed X axis from the origin defined in step 2 and place it about 24 inches in front of this origin 5 Press P and write down the X Y Z measurements These will be Xx Xy Xz 37 JUNE 2012 POLHEMUS INNOVATION IN MoTION FASTRAK MANUAL 6 Move the receiver along the proposed Y axis from the origin defined in step 2 and place it about 24 inches from the transmitter 7 Press P and write down the X Y Z measurements These will be Yx Y y Yz 8 Using all of the data that has been written down in steps 1 7 send the command A1 O0x Oy Oz Xx Xy Xz Yx Yy YZ lt gt Enhanced Alignment Procedure A capability of the alignment command is called the Enhanced Alignment The Enhanced Alignment feature allows the user to perform an alignment quickly and easily The procedure is as follows 1 Select the lowest station number receiver selected usually station 1 2 Issue the command A0 Sending this command prepares the system for collection of alignment data 3 data points and resets previous alignments by sending the commands R1 R2 lt gt R3 lt gt and R4 lt gt 3 Place the receiver at the proposed origin location and press P once 4 Move the receiver along the proposed positive X axis from the origin and place it about 18 to 24 from the transmitter and press P once 5 Move the receiver along the proposed positive Y axis from the origin and place it about 18 to 24 from the transmitter and

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