Home

IS-600 XL Manual

Contents

1. Add Delete Copy Change Apply When setting up a Fusion Mode station you must enter the positions of 3 optical sensors relative to the InertiaCube Px Py and Pz in the screen above The coordinate system for these values is the body of the InertiaCube where X is forward Y is to the right and Z is down see Figure 20 The origin is located in the exact center of the bottom of the base of the InertiaCube All values are entered in meters Please see Figure 20 You must also enter the directional vector representing the orientation of the optical sensors in the InertiaCube body coordinate frame Nx Ny and Nz in the screen above This orientation should be interpreted as the direction of maximum visibility of the optical sensor 29 Position Sensor Data Entry A Normal Vector pointing up 0 0 1 b Optical Sensor InertiaCube Figure 20 Position Sensor Coordinates To change the configuration of a sensor double click on the corresponding line or press Change Important After entering or changing data you must explicitly activate these changes by selecting Apply Configuration item in the Commands menu or pressing the Apply button This sends the new PSE configuration to the tracker and checks if it was applied properly by trying to retrieve it back This window lets you change the configuration parameters of a particular Mobile PSE Station corresponds to the station number that this optical sen
2. Bytes Explanation 1 Record type 2 2 Station Number Always 1 3 Sub Record type S 4 Config Hex Char 0 5 Config Hex Char 1 6 Config Hex Char 2 7 9 BIT error Currently unused 10 15 Blank 16 21 Firmware version ID 22 53 System Identification 54 55 CR LF To decode each of the Config bytes Config Hex Char 0 Unused Config Hex Char 1 Unused Config Hex Char 2 Bit Meaning 0 Output Format 02 ASCII 1 Binary 1 Output Units O Inches 1 Centimeters 2 Unused 3 Transmit Mode 0 Polled 1 Continuous Output List Record This record is sent in response to a Of stationNum lt gt command It returns the list of currently selected output parameters for that station 2 bytes per item 2 stationNum O parlpar2 parN Bytes Explanation 1 Record type 2 2 Station Number 3 Sub Record type O 4 5 parl 6 7 par2 CR LF For example the default data list would be returned as 210241 54 Station State Record This record is sent in response to a If stationNum lt gt command StationNum is ignored and the record returns the state of the first four stations This maintains the compatibility with the Fastrak protocol Output values of are interpreted as 1 for ON and 0 as OFF 2 stationNum l statl stat2stat3stat4 c lt c e n Explanation Record type 2 Station Number 1 2 3 4 Sub Record type T State of station 1 State of station 2 State of station 3 State of station 4
3. This command is similar to Alignment Reference Frame command except it only affects orientation and not position output This command is ignored if station is configured for Fusion Mode b stationNum lt gt Firmware Version 2 x compatibility mode Mb stationNum lt gt Fastrak compatibility mode Clears the orientation coordinate frame changes produced by the Heading Boresight command 40 Set Communication Parameters o rate parity bits HHS lt gt System Record Request Station Status Output Units Control System control Output record mode rate parity bits HHS Default Parity bits AHS Change the communication parameters is one of 3 12 24 48 96 192 384 576 1152 rate is multiplied by 100 N none O odd E even Tor 8 Hardware handshake 0 OFF 1 ON Baud rate depends on hardware mode switch N 8 OFF Request a system status record to be sent l stationNum state State Default U u Default K W Ay S Q Caution F f Default set the stationNum on or off 0 OFF 1 ON Only station 1 is on Sets output data record position units to inches Sets the position units to centimeters This command is not relevant to the IS 300 U Save the current settings to nonvolatile memory Restore the system settings to the factory defaults Restart the firmware to the power up condition Suspend data transmission Resume data transmissi
4. eene tee Heading Boresight Help EE AT E IT edendi Hemisphere ISDEMO 4 oie Rm mme 28 Inches InertiaCube assignment den vente 48 58 73 ISDEMO placement recommendations technology overview lat ney toos Renate ame aiu 51 LF line feed S30 Load and Save Factory Settings 522 Load Power Up Settings esee 22 M Magnetic Sensor Configuration cesses 29 Hardwaie ID 2 5 EUN errors Peer es 49 Magnetic Tracket 2 nere 14 Hemisphere Magn tometer sss oau toe etre tere Mobile PSE Ziru tee Ree ico te one e E ated commands O Optical Fracker js A T as ee a eee latency miei RH e Source Frame sss Output Mode commads E BB ISDEMO system status record Output Record List comimatd oic uit ERES 42 72 IeCOIQ A nos nassnei e A 54 Output Units e a eee 54 P Patents 5 sete ete een Ds 2 Perceptual Enhancement ISDEMO Polh mus a Kirra e eerte ee eei deerit eese dese eie dese Polled Mode command esasen ai DIEI YT data records system status record Precautionary Statements sese 3 Prediction Command iiu e DEN 47 73 ISDEM O eedem nen 27 T6COIQN edere eo EC ia tono 59 PSE Position Sensing Element 29 79 Q Quate oN en n RAS 42 43 R Rec iverP od ann nee RSRPUSPERREE 29 Refresh iie ie eU ESO Ee ERR IUE 27 Rotation Matrix 4
5. 37 Frames s Station 1 ON Display is ON Choose Com or Com2 shown above Some versions of ISDEMO may have Com3 and Com4 listed as well You have the option of choosing one of four baud rates 9 600 19 200 38 400 115 200 When chosen this option will automatically detect the port and the baud rate being used The program attempts to establish communication by sending the command status record request and waiting for a response for 2 seconds If the status record is not received within that time the program tries again with the different communication parameters E Autodetect Communication Parameters Lx Press Detect to start accept cancel 23 4 4 Parameter options Parameters menu gives you access to the tracker configuration controls imi ISDEMO Configured for IS 600 Series device nl x File Commun 271 Records s 0 Frames s ON Display is OFF 4 4 1 Tracker System Parameters acke em Configuration Continuous Mode Inches Centimeters ASCII P BINARY Binary Output Mode Polled or Continuous In Polled mode data records are sent out only in response to a P command Measurement output record Inches Centimeters 24 Data Format ASCII F command Numbers are returned in ASCII format Each number has 7 ASCII characters a sign 3 digits a decimal point and 2 more digits Binary f command Floats are sent as 4 bytes of IEEE 32 bit floats This can increase t
6. 9 CR LF oo 109 tA 4 0 02 Alignment Reference Frame Record This record is sent in response to an AfstationNum lt gt command It returns 9 ASCII floats that were last set with the A command Each float is represented as 7 characters with 2 digits after the floating point 2 stationNum A OxOyOzXxXyXzYxYyYz Bytes Explanation 1 Record type 2 2 Station Number 3 Sub Record type A 4 24 OxOyOz origin coordinates 25 45 XxXyXz vector in the direction of the positive x axis 46 66 YxYyYz vector in the direction of the positive y axis 67 68 CR LF 55 Boresight Reference Angles Record This record is sent in response to a G stationNum lt gt command It returns 3 ASCII floats that were last set with the G command Each float is represented as 7 characters with 2 digits after the floating point 2 stationNum G yawref pitchref rollref lt gt Bytes Explanation 1 Record type 2 2 Station Number 3 Sub Record type G 4 10 yawref azimuth reference angle 11 17 pitchref elevation reference angle 18 24 rollref roll reference angle 25 26 CR LF 56 5 3 3 InterSense specific Records Manufacturer System Status Record This record is sent in response to an MS lt gt command It returns a status record specific to the InterSense system 31S statusRecord lt gt Bytes Explanation 1 Record type 3 2 Station number Always 1 3 Sub Record type S 4 Config Hex Cha
7. Degree Of Freedom DOF tracker It obtains its primary motion sensing data using a miniature solid state inertial measurement unit InertiaCube which senses angular rate of rotation gravity and earth components along three perpendicular axes The angular rates are integrated to obtain the orientation yaw pitch and roll of the sensor Gravitometer and compass measurements are used to prevent the accumulation of gyroscopic drift IS 600 The IS 600 uses an InertiaCube to sense angular rate of rotation and linear acceleration along three perpendicular axes The angular rates are integrated to obtain the orientation yaw pitch and roll of the sensor and the linear accelerations are transformed into a reference coordinate frame and double integrated to keep track of changes in position x y and z Ultrasonic time of flight distance measurements are used to obtain a starting position and to correct any drift in the inertial position and orientation tracking 19 IS 900 The IS 900 is similar to the IS 600 except the roles of the SoniDiscs and ReceiverPods are reversed Ultrasonic range measurements are made with respect to an array of SoniDiscs The array is positioned over the required tracking area or on a wall behind the tracker or both The SoniDiscs are triggered by infrared triggering codes and they respond by emitting an ultrasonic chirp which propagates through the air Three ReceiverPods mounted in the tracker then detect this
8. Numbers Floating point numbers can be returned as IEEE 32 bit floats or as ASCII numbers in X xf notation where X is the total number of characters used to represent the float x is the number of digits after the floating point f symbol indicating that number is a float For example number 42 6 in 0 4f format would look as follows 42 6000 Status Record Hexadecimal Character Decoding System Status Manufacturer Status and Manufacturer Station records use Hexadecimal Characters to encode status data Each character can be 0 to F and can encode 4 bits Logical AND operator can be used to test specific bits Please see following code example unsigned short byte1 byte2 byte3 char hexChar 2 hexChar 1 0x00 hexChar 0 statusRecordBuffer 3 sscanf hexChar x amp byte1 hexChar 0 statusRecordBuffer 4 sscanf hexChar x amp byte2 hexChar 0 statusRecordBuffer 5 sscanf hexChar x amp byte3 52 5 3 2 Fastrak System and Data Records Data Record Example This record is sent in response to a P command in polled mode or continuously in continuous mode A separate data record is sent for each active station The list of data items in each station record depends on how the list was set up with the O command For most of the commonly used data list items the format depends on commands F f U u MT Mt Of stationNum status datalItem1 dataltem2 stationNum A number from
9. Send Boresight Command Send Unboresight Command Send Reset Angles Command Mode 0 provides the best accuracy The inertial tracker uses gyros to measure angular rotation rates for computing the sensor s orientation To compensate for the gyroscopic drift depending on the configuration the tracker may use accelerometers magnetometers or optical system to measure the actual physical orientation of the sensor That data is then used to compute the necessary correction In Mode 0 correction adjustments are made immediately no jitter reduction algorithms are used This results in somewhat jumpy output not recommended for head tracking but with lower RMS error Use this mode for accuracy testing or for any application that requires best accuracy Mode 1 provides accuracy similar to that of mode 0 with an addition of a jitter reduction algorithm This algorithm reduces the accuracy by only a small amount and does not add any latency to the measurements Mode 2 is recommended for use with HMD or other immersive applications The drift correction adjustments are made smoothly and only while the sensor is moving so as to be transparent to the user This setting is only used when Perceptual Enhancement Level is set to 2 It controls the minimum angular rotation rate picked up by the InertiaCube Default is level 3 Increasing sensitivity does not increase latency during normal movements It may however result in some small residual movements
10. can use this function for test and debug purposes Type in the command and press Enter or Return The lt CR LF gt pair is automatically added to the end of the line before it is written to the serial port ili Send Command x Commands Help Command String See Section 5 Interface Communication Protocol for the complete list of all available commands This option allows you to send an entire file to the tracker over the serial port This tool may be useful if you would like to keep a list of tracker configuration commands in a file Send Command File opens a file selection dialog in which you can identify the file directory and drive of a command file to be sent When creating a command file please enter commands one per line It is not necessary to add CR and LF to any lines in the file Please Select a File x configl txt config2 txt config3 26 6 9 35 System Information formation This window provides a summary of the InterSense tracker system configuration Data Capture Playback Utility ISDEMO has the ability to write the data it receives from the tracker to a file To utilize this feature you must first specify the name and location of the output file To start data collection select Record Data can be saved As Is or in an ASCII or binary flat file When Flat File option is selected only tracker data is saved one line per update cycle If you are planning to import data to Excel o
11. chirp The ReceiverPods and associated electronics on the tracker measure the time of flight and thereby obtain range measurements from the camera to whatever SoniDiscs are nearby and visible IS 600 XL The IS 600 XL uses an InertiaCube to sense angular rate of rotation and linear acceleration along three perpendicular axes The angular rates are integrated to obtain the orientation yaw pitch and roll of the sensor and the linear accelerations are transformed into a reference coordinate frame and double integrated to keep track of changes in position x y and z Position data from the attached optical tracker is used to obtain a starting position and to correct any drift in the inertial position and orientation tracking Note You must select IS 300 or IS 600 XL or ISDEMO will not be able to correctly configure your tracker 20 ISDEMO Main window ISDEMO has six primary menus in its main window 4 2 File options File Communications Parameters Display Tools Help lii ISDEMO Configured for IS 600 Series device File Communications Parameters Dis CEELB ETE Ctrl4Q dd 78 91Kbps 272 Records s 73 Frames s Station 1 ON Display is ON The File menu shown above provides you with the following options Select Hardware Device Save Current Settings Select Hardware Device Boresight Current Station Unboresight Current Station Save Current Settings Load Power up Settings Load and Save Factor
12. effects induced in users of real time computing systems that include various types of tracking sensors This research has reported the symptoms described below from some users of these systems IS 300 has been designed using the latest sensor technologies and we believe that the possibility of such symptoms occurring has been minimized However it is not possible to design for the individual characteristics of each user and it is possible that users will experience one or more of the side effects described below Historic research shows that the effects or symptoms ordinarily occur during and immediately after use and should diminish quickly once the user stops using the system We want you to make an informed and responsible choice about using the IS 300 Accordingly we warn you that even if you read and follow the User Instructions you may experience one or more of the following effects or symptoms if you use IS 300 with a personal display eye strain altered vision eye or muscle twitching headaches neck and shoulder strain nausea and vomiting disorientation dizziness impaired balance and stability drowsiness fainting fatigue sweating extreme paleness impaired hand eye or other co ordination Each effect or symptom if it occurs should be temporary and may last from a few minutes to 30 minutes 70 Appendix E Care and Maintenance Care and Cleaning The first step to keeping your IS 300 clean is to keep dirt and dust
13. for a couple of seconds after the sensor has stopped If your application requires sensitivity greater than maximum provided by this control you must use Perceptual Enhancement level 0 or 1 instead InterSense tracker models IS 300 Pro and higher can predict motion up to 50 ms into the future which compensates for graphics rendering delays and further contributes to eliminating simulator lag This feature is only available for stations configured with an InertiaCube Program requests status records for all the parameters displayed in this dialog box Settings are displayed as soon as they are received If records are not received within two seconds a communication error is assumed Sends boresight command to the station being configured Reverses the effects of the boresight command Reverses the effects of the Alignment Reference Frame command 27 4 4 3 XL Tracker Setup XL Tracking System Configuration Sagies SM3D Le Right Source Frame Position and Orientation Position I0 0000 ES Ee keisi aj 0 0000 IES keko saa O 0000 This screen lets you setup the supported auxiliary position tracking system By default None is selected and the tracker works like a regular IS 300 orientation tracker If you choose to use the XL option you must specify the type of tracker connected to the Data In port of the IS 300 base unit Hemisphere is the feature of the magnetic systems and not applicable to optical trackers Source Fr
14. half rate 1f state is 1 update rate will equal 15 Hz If state is 3 and the specified rate is too high the update rate will equal 15 Hz Using CrystalEyes To configure an IS 600 Mark 2 or IS 900 CT for use with CrystalEyes set the sync signal type switch to TTL and send the command MG2 120 or MG2 60 to the tracker Adjusting Phase Point A data record is output once per sync period when the tracker is in continuous mode The phase point is the time within the sync period at which a data record is transmitted and is adjustable for internal and external Genlock The phase point is specified as a percentage of the sync period 0 the default instructs the tracker to output a data record as soon as possible after the sync period begins 100 delays the output of a record as much as possible before the next sync period begins To adjust phase point via command MGP lt gt Increase decrease to next preceding phase point MGP p Set phase point to percentage specified by p 0 to 100 The current phase point is reported if the command is issued without parameters or invalid ones The tracker will accept the first form of the command only after Genlock is established With the second form of the command the tracker will match the specified phase point as best it can but typically with far less resolution than 1 100 of the sync period To set the phase point via the LCD menu select System Config Genlock Phase Set and change
15. so as to be transparent to the user Default 2 Rotational Sensitivity Level MOf stationNum Sensitivity Level lt gt Adjusts rotational sensitivity of a station These settings are only applicable when the Perceptual Enhancement Level is set to 2 Sensitivity Level is an integer 1 to 4 where 1 is the lowest and 4 is the highest sensitivity If optional parameter is omitted current value is returned Default 3 47 5 2 3 Station Component Configuration Commands Associate InertiaCube with a Station MCI station number InertiaCube number This command assigns an InertiaCube to a station If the second parameter is omitted current assignment information is returned The InertiaCube number can be 1 to 4 and is the same as the number of the connector on the tracker This command does not take effect until explicitly activated by the MCe lt gt command Disassociate InertiaCube from a Station MCi stationNum InertiaCube number This command removes an InertiaCube from the station configuration The InertiaCube number can be 1 to 4 and is the same as the number of the connectors on the tracker If the station number and the InertiaCube number are not associated in the current this configuration command is ignored If both parameters are omitted all station to InertiaCube associations are cleared This command does not take effect until explicitly activated by the MCe command Associate Mobile PSE with a st
16. supply output record rate Default 0 MGP Param Param can be the Phase 0 to 100 or to increase to the next phase point or to decrease to the next phase point Please see Appendix A for complete details Default 0 45 5 2 2 InterSense specific Station Parameters InterSense Station Status Record Request Ms stationNum lt gt Request an individual sensor status record for stationNum This is information about parameters which are specific to the InterSense product Compass Heading Correction MH stationNum mode lt gt This controls the state of the compass component of the InertiaCube To operate effectively the magnetic field in your workspace needs to be homogeneous this can be difficult to arrange in a typical work environment Mode 0 Compass is OFF no heading compensation is applied Not recommended Modes 1 or 2 are preferred Mode 1 Partial compass mode Magnetometer readings are used to reduce drift and maintain stability but not as an absolute measurement system In this mode system is much less susceptible to magnetic interference but heading drift will slowly accumulate This mode is particularly useful when high rotational sensitivity settings are used Mode 2 FULL compass mode Readings produced by the magnetometers inside the InertiaCube are used as the absolute reference orientation for yaw For backward compatibility old style commands MH stationNum lt gt and Mh s
17. the coordinate system of the tracker It simply saves the current position and subtracts it from all the future data points before drawing them on the screen Zoom options Zoom in PageUp Zoom out PageDn Changes the display scale Please note that zooming in may cause the sensor to disappear from the screen Use Reset Origin menu item to bring it back in the view This option is used to display tracking status information for all stations The top row lists 12 stations which is the maximum supported by the current interface protocol The second row displays the tracking status Stations configured for GEOS Mode always display T Tracking Stations running in Fusion Mode display T when tracking position and L Lost when position tracking is not possible If a station configuration is invalid X is displayed Station Status Display Commands Help Alo call aly Row 3 displays the number of measurements received by each station during the last cycle In the case of IS 600 XL a measurement is defined as one sensor data point received from the attached optical tracker Row 4 displays the number of measurements rejected by the system This number should normally be zero 34 Send Command String Send Command File Send Command String allows you to send single line commands to the tracker This tool is provided to allow control over the tracker parameters not supported in the menus and dialogs For instance you
18. tracker base unit For an IS 600 Mark 2 or IS 900 CT connect the sync signal to the BNC connector labeled Sync In on the back of the tracker base unit Select the appropriate signal type by setting the switch near the BNC connector to TTL or NTSC Enabling Genlock via Command Send the C command to the tracker to place it in continuous mode If the tracker is used in polled mode its internal updates will be synchronized to the sync signal but data record output will not Send the InterSense specific Genlock command to the tracker MG state rate lt gt state 0 Genlock off free run 1 Use external sync autodetect strobe rate 30 Hz minimum 2 Use external sync strobe rate specified by rate parameter manual 3 Use internal sync output data records at frequency specified by rate parameter rate For state 2 the sync strobe rate in hertz For state 3 the data record output rate in hertz 30 Hz minimum in either case Note Use of state 1 is recommended instead of state 2 to avoid inadvertently specifying a rate that does not match the actual input strobe rate and may prevent synchronization Current settings of state and rate are reported if the command is issued without parameters or invalid ones The Fastrak command y state is interchangeable with the MG command with state equal to 0 or 1 ISDEMO can be used to send the Genlock command using the Send Command String option Genlock settings can be saved to the tracker u
19. 0x007F hi dataRecord 4 amp 0x007F int14bit lo 2 hi 9 result float int14bit 1 0 32768 0 Resulting quaternion value has range of 1 0 44 5 2 InterSense Specific Commands All InterSense specific commands start with the letter M for Manufacturer specific and must be completed by a CR LF pair 5 2 System Configuration Commands Time Units The time stamp recorded is the time when the tracker data was collected from the hardware The time index is set to zero when tracker is first turned on MT Setsthe units for the data record time stamp to milliseconds Mt Sets the units for the data record time stamp to microseconds Default T InterSense System Status Record Request MS lt gt Request the manufacturer specific system status record This is information about parameters which are specific to the InterSense product additional to the standard system status information obtained using the S command Tracking Status Record Request Set Current Time to Zero Genlock Synchronization Genlock Phase MP Requests tracking status information for all 12 stations See Section 6 3 4 for the description MZ This command sets current time index of the tracker to zero MG State Rate lt gt State 0 Genlock is off 1 External sync autodetect strobe rate not implemented in release 3 0161 2 External sync manual supply strobe rate 3 Internal sync
20. 1 to 4 status An ASCII space character This status byte is currently unused dataltemX ASCII In ASCII numbers set with the F command any numbers returned as floats are returned as ASCII numbers Each number is 7 ASCII characters a sign 3 digits a decimal point and 2 more digits If programming in C use scanf 07 2f amp value to read them Binary In binary mode set with the f command the floats are sent as 4 byte IEEE 32 bit floats Time Stamp 32 bit floating point number ASCII In ASCII mode it is allowed 14 characters and is displayed as an integer digits after the floating point are ignored Binary In binary mode it is returned as a 32 bit float Binary16 mode Set by selecting 18 19 and or 20 only with the O command This is the fastest way to get data but the most difficult to decode and the least accurate For the default data record O1 2 4 in ASCII mode F The output record set for the active stations 1 and 2 would look as follows 01 1 23 41 83 12 18 13 04 76 11 34 12CRLF 02 23 01 452 94 0 01 1 01 23 32 12 34CRLF For station 1 x 1 23 y 41 83 z z12 18 yaw 13 04 pitch 76 11 and roll 34 12 For station 2 x 23 01 y 452 94 z 0 01 yaw 1 01 pitch 23 32 and roll 12 34 53 System Status Record This record is sent in response to the S command It contains system wide status information Some of the information in the status record must be bit decoded 2IS statusRecord
21. 2f ASCII format 62 68 Hardware ID code in ASCII format 69 70 CR LF 59 Tracking Status Record Sent in response to MP lt gt command It returns the tracking status information for 12 stations allowed by the interface protocol A measurement is defined as one sensor data point received from the optical tracker 510 Tracking state record lt gt Station Number Always 1 Tracking state identifier for station 1 State can be L if lost T for tracking or X for invalid Please see Section 4 6 of this manual for complete description Number of measurements received this cycle Number of measurements rejected Tracking state identifier for station N Update rate per station Bytes Explanation 1 Record type 5 2 3 Unused Always 0 4 5 6 343 N 39 43 44 45 CR LF 60 5 3 4 XL System Configuration Records XL System Configuration record Hemisphere record Source Frame record Sent in response to MXS command It returns the identifier of the currently configured auxiliary tracking system 31XS Mode lt gt Bytes Explanation 1 Record type 3 2 Station Number Always 1 3 4 Sub Record type XS 5 Auxiliary system identifier 0 None 1 Polhemus Fastrak 2 Ascension Flock of Birds 3 Sagies SM3D Optical Tracker 6 7 CR LF Sent in response to MXH lt gt command It returns the current settings of the hemisphere parameter Bytes Explanation 1 Record t
22. 3 Rotational Sensitivity See Sensitivity RS 232 Pin assignment incana 66 SEINES EE 23 41 72 Send Command String Sensitivity commiand e REIR ISDEMO edu T M Shortcut Keys eH Rep REHAB RSS Software compatibility ISDEMO SoniDisc nte nee rt E R eb ab eb ib eda 29 Source Frame command need 51 ISDEMO foci sis cca de cade 0s cade d0e cade neaei is 28 record drei ebeb eie 61 Start Displaying Data Station iustitie E Fete et Fett ste Pest ete Penh eroi 25 state StereoGraphics Synchronization ssssss Synchronize to monitor esee System Information System Initialization window T Time Stamp Time Units m Tracker System Parameters 24 Tracking Statistics ISDEMO idc E esie see n tenons 34 senum 60 Transformation Matrix See Rotation Matrix U Unboresight comimarid 3 RR RU ia i i 40 72 ISDEMO Win32 NT sample code sess 14 X XL Mode command ISDEMO latency sunm MC Y Yaw Boresight 72 See Heading Boresight 76
23. 66 Q7 Q8 To connect up to a Mini DIN 8 Mac s amp SGI s or a DB 25 serial port use this table InterSense signal InterSense DB9 DIN 8 DB 25 RX 2 3 TX 3 TX TX 3 5 RX 2 RX GND 5 4 GND 7 GND Note that you must connect up RX TX and TX gt RX So the bottom line is that you only need three wires RX TX and GND Do you have any advice about working with software packages Some software packages such as Sense8 will not work if more than one sensor is turned on We recommend that you turn off all sensors except one and save the settings How do I know whether I have the latest release of ISDEMO Check our web site the URL is http www isense com support html Click on the ISDEMO ZIP hypertext link We always post the latest release for you to download 67 Appendix C Troubleshooting Problem ISDEMO doesn t work ISDEMO is communicating but system does not track InertiaCube interference Orientation is drifting uncontrollably Reason Solution Most common reasons not in any order 1 2 3 4 5 6 7 Not using a NULL modem cable Connected to wrong Com port plug on the back of the computer The selected serial port is captured by another program and can t be opened by ISDEMO Serial port not capable of running at desired baud rate This is usually due to older computers that cannot run at 115200 baud The problem is a lack of a proper UART such as the 16550 Inco
24. User Manual for IS 300 Pro IS 600 XL Optical Systems Firmware versions 3 0171 and above Contacting InterSense Please do not hesitate to contact us for any reason We are here to help and we value your business InterSense Inc 73 Second Avenue Burlington Massachusetts 01803 USA Telephone 781 270 0090 email info isense com Fax 781 229 8995 Internet www isense com Regulatory Statements and Approvals C United States FCC Part 15 Subpart B Class A This device complies with part 15 of the FCC Rules Operation is subject to the following two conditions 1 This device may not cause harmful interference and 2 this device must accept any interference received including interference that may cause undesired operation Canada This Class A digital apparatus meets all requirements of the Canadian Interference Causing Equipment Regulations Europe EN60950 EN55022 Class A EN50082 1 Warning This is a Class A product In a domestic environment this product may cause radio interference in which case the user may be required to take adequate measures 072 00005 0E99 Patents The label below identifies the protection granted by the Government of the United States to InterSense for its products U S Patents 5645077 5807284 and patents pending INTERSENSE Trademarks InterSense InertiaCube SoniDisc GEOS PULSAR CONSTELLATION are trademarks of InterSense Inc All other trad
25. a To prevent graphics updates from taking over most of the processor time no more than 20 data records per second are displayed Please note that whenever your tracker is in continuous mode records are displayed in the text window even when the display is off 600 Series device i OL x T9 9 DO 9 9 DO C0 CO CO o C CO 0 c 9 64Kbps Station 1 ON Display is ON Turns on off the numeric readout for X Y Z Pitch Yaw and Roll This can be useful when running on a very slow computer This option is only available in DOS version and is designed to reduce the flickering of the image during data display It attempts to do all drawing between monitor refresh cycles This however limits the frame rate to a maximum of 60 fps and with numeric and analog display will likely reduce it to 30 or below depending on the speed of your computer 32 4 6 Tools Options Display Tools Help Display Position Display Tracking Statistics Send Command File System Information Data Capture Utility 79 57Kbps 275 Records s 0 Frames s Station 1 ON Display is OFF Display Position Allows you to view the position and yaw of the currently displayed station L Position Display x Commands Zoom He 1 unit 3 00 inches 33 Display Tracking Statistics File options Start Displaying Data Crtl D Stop Displaying Data Crtl X Exit Crtl Q Command options Reset Origin Crtl R This command does not change
26. ame Position and Orientation controls are used to specify the orientation and position of the optical system in a user defined locally leveled coordinate system When a multi camera system like Qualisys is used then Source Frame is the world coordinate system of the optical tracker 28 4 4 4 Setup Position Sensors Terminology Mobile PSE Configuration IS 600 and IS 900 models contain an ultrasonic subsystem that includes SoniDiscs Ultrasonic Transponder Beacons and ReceiverPods Ultrasonic Receiver Modules To generalize the interface protocol and configuration tools for these tracker models we defined a new term PSE Position Sensing Element Same terminology is also applied to IS 600 XL A PSE may be Mobile or Fixed Mobile PSEs are assigned to the stations and their movements are tracked by the system Fixed PSEs form a CONSTELLATION and must not be moved In the case of the IS 600 XL optical sensor is considered to be a mobile PSE Fixed PSE setup is replaced with the Source Frame configuration and not needed here Note All position data for PSEs is entered in meters To track position a station must have 3 optical sensors associated with it This window lets you add delete and configure these Mobile PSEs for all the stations E Mobile PSE Configuration x Commands File Help Station PSE Px 1 0 0000 0 0000 0 0564 0 00 0 00 2 0 1524 0 0000 0 0157 0 00 0 00 1 00 0 0244 0 0354 0 0157 0 00 0 00 1 00
27. are and hardware including products from Virtual Research eSuperscape Sense8 MetaVR Division Kaiser Electro Optics Softimage eMultigen enVision Xtensory homson T amp S 12 Setting up your new IS 300 3 1 IS 300 IS 600 XL Components IS 300 IS 300 Pro E ISDEMO InertiaCube Configuration Software IS 300 Base Unit The base unit is the processing engine of the IS 300 system It has the following connections InertiaCubes up to 4 via cable attached to the InertiaCubes Power via 12V DC power supply User s Computer via null modem RS232 cable The base unit should be installed in a clean dry environment 13 InertiaCube sensors Optional Optical Tracker Software The InertiaCube orientation sensors come with 10 foot cables that plug into the IS 300 Base Unit NOTE the InertiaCube sensor is a precision instrument Care must be taken when handling this device Most of our customers attach the InertiaCube to devices that are more fragile than the InertiaCube and hence require that the whole system must be handled carefully Although the product can withstand the normal wear and tear experienced by a premium HMD or other device abrupt actions such as dropping it or banging it against another object can permanently damage the InertiaCube By connecting an optical tracker to the auxiliary serial port marked Data In of the IS 300 Pro it can be made into a GDOF inertial optical hybrid tracker Use 115200 bau
28. ata record ISDEMO s Autodetect communications B rrjg 13 mode sy C E 16 Baud Rate command ISDEMO iode switch asas a 16 Binary 16 format eee UR 43 Binary format cormarid oR ARAL 41 72 Gata record serrer 53 ISDEMO i TEE 25 Boresight commands ccsscccscesseesacessescacsssescscesnchcoetse 39 72 compatibility with Fastrak 39 72 C Centimeters e eee ee eese aia ees 54 Communications auto detecting 2c cn o t es 23 comman Asoro iers a E ISDEMO Compatibility Constellation Continuous Mode system status record Corloli eet CR carriage return E CrystalByes eee epe te Reed D Data CAPUT veia d DE Dette 36 format command c eSNERSUNERSNREDRRERNGRSE TSE cis i oe Se UE ctus OQULPULTECOL ene eaasud em Direction Cosines Display Position i erii treten ttes Display Text i eee E edo DOS KPM OT e ns ISDEMO window management i Sainple code RR Eu 74 Fastrak ved HG ARORA 11 38 Filesment 3 nen Rononedencecncenatng 21 Firmware Version nnn an 54 Fixed PSE ar he i ona 29 Fusion Mode CONN SUTIN seein eee hele 29 CescriptiOns accent eerte ve ate o 9 monitoring ISDEMO un oh 6s Sees HORROR SAAR 34 status record hennen ononon on DnA Oe 60 status record request sess 45 G GEOS Mode d SCEIDUOR uere t cH ERES 8 H Hardware ID Mobile PSES 5
29. ation MCM stationNum MPSE number xp yp zp xn yn zn IDcode lt gt Configures or adds a Mobile PSE For an IS 600 XL a Mobile PSE is an optical sensor If only the stationNum parameter is provided then the current data for that station is returned on the serial port one PSE per record Please note that only the records for configured PSEs are returned If stationNum and MPSE number are present then the current data for that PSE is returned If that PSE is not configured record will contain Hardware ID of 1 If no parameters are provided then data for all configured PSEs for all stations is returned each PSE in a separate record This command does not take effect until explicitly activated by the MCe lt gt command 48 stationNum A unique number identifying a station MPSE number From 1 to 8 only Unique number identifying one Mobile PSE out of the set attached to the station It identifies PSE within one station and starts with 1 for each station Xp yp zp Position vector in meters When setting up a Fusion Mode station user must enter position of an optical sensor relative to the InertiaCube The coordinate system for these values is the frame of the InertiaCube where X is forward Y is to the right and Z is down The origin is located in the exact center of the base of the InertiaCube Coordinates of the optical sensors are measured in meters to typically the geometric center of the sensor xn yn za Nor
30. ation is changed and during any boresight operations e tis recommended though not required that you wait for the InertiaCube to warm up it achieves optimal performance after warming up for at least 15 20 minutes e The InertiaCube is tuned for normal head motion Avoid shaking vibration Remember this precision instrument uses angular rate sensors which sense smooth regular movement very well If you keep these guidelines in mind your IS 300 will deliver superb performance 17 ISDEMO Testing the IS 300 ISDEMO is included as a test diagnostics configuration tool With it you can test all the features of your tracker You can also use it to set and save tracker configurations Software included with your tracking device includes the following 1 ISDEMO32 EXE Win32 version To be used under Windows95 98 and NT 2 ISDEMO EXE DOS version of ISDEMO program 3 ISDEMO HLP A file which contains help text also reprinted here ISDEMO provides a convenient graphical interface that can configure most of the tracker parameters There are however some advanced features that it does not support These features can be configured by sending single line commands through the serial port See the section titled Interface Communication Protocol for descriptions of all the available commands 4 1 Getting Started Create a directory on your hard drive where you would like the program to be installed Copy all files and directories fro
31. ch to Fastrak Compatible mode 40 MBI lt gt Switch to Version 2 x Compatible mode Boresight B stationNum lt gt Fastrak compatibility mode 41 MB stationNum lt gt Version 2 x compatibility mode Unboresight b stationNum lt gt Fastrak compatibility mode 41 Mb stationNum lt gt Version 2 x compatibility mode Heading Boresight B stationNum lt gt Version 2 x compatibility mode 41 MB stationNum lt gt Fastrak compatibility mode Heading Unboresight b stationNum lt gt Version 2 x compatibility mode 41 Mbf stationNum lt gt Fastrak compatibility mode Set Communication Parameters o rate parity bits HHS lt gt 42 System Record Request S 42 Station Status l stationNum state lt gt 42 Output Units Control U Setunits to inches 42 u Set units to centimeters System control K Save the current settings to nonvolatile memory 42 W Restore to the factory defaults Y Restart the firmware to the power up condition S Suspend data transmission O Resume data transmission Output record mode F Putin ASCII output mode 42 f Putin Binary output mode Output record list settings Ol stationNum pl p2 p3 pn 43 72 Time Units Set Current Time to Zero InterSense System Status Record Request Tracking Status Record Request Genlock Synchronization Genlock Phase InterSense Station Status Record Request Compass Heading Correction Prediction Interval Perceptua
32. chronization signal and then decides upon a tracking loop update rate which is the highest multiple of this frequency that it can consistently maintain In the example in the diagram the tracker has decided to do 4 internal updates per display refresh cycle However ONLY ONCE per display refresh cycle is data output across the serial port to the host This point by default is at the end of the last update cycle in the field labeled 8 in the diagram above Using this point or point 7 provides the lowest possible end to end latency only 11 4 video fields in this example However if the time to transmit the data across the serial port and accomplish all necessary processing and rendering cannot be guaranteed to be strictly limited to 16 7ms on every single cycle there will be cycles when the rendering does not complete in time for the next scan out resulting in a disturbing glitch in the image By choosing to have the serial port data output occur at one of the earlier numbered phase points there is a bit more latency but also more slack to allow for an occasional rendering cycle that just slightly exceeds the allotted 16 ms The following diagram illustrates the tracker set up to output data at phase point 3 The rendering time of the second cycle has been extended slightly as illustrated by the black bar and the timing slack has absorbed this anomaly so that the image is still rendered with the same 124 frame latency as the frames before it resul
33. d from Euler angles cos P cos Y sin R sin P cos Y cos R sin Y cos R sin P cos Y sin R sin cos P sin Y sin R sin P sin Y cos R cos Y cos R sin P sin Y sin R cos Y sin P cos P sin R cos P cos R Data Item 11 Orientation Quaternion Quaternion is returned as q w x y z Quaternion to rotation matrix conversion can be accomplished using the following formula 120y 227 2xy 2WZ 2xz 2wy 2xy 2wz 152x 27 2yz 2wx 2xz 2wy 2yz 2wx 1 2x 2y Data Items 18 19 20 16 bit binary format 16 bit binary format can be used in applications requiring fastest possible serial I O Each floating point number is stored in 2 bytes with only 14 bits containing actual data This results in lower accuracy than the standard IEEE floating point format Data is 2 s complement The first byte of the data set has its high order bit set to 1 all others have them set to zero This can be used for data synchronization Data is returned low order byte then high order byte Use following code sample as an example on how to decode this format To decode Euler angles lo dataRecord 3 amp 0x007F hi dataRecord 4 amp 0x007F int14bit lo 2 hi 9 result float int14bit 180 0 32768 0 43 Resulting number represents orientation and has a full range of 180 0 180 0 to 179 978 degrees To decode Orientation Quaternion lo dataRecord 3 amp
34. d serial link via a standard null modem rs232 cable The following software is included with the system and is explained in great detail in Section 4 1l ISDEMO32 EXE For Windows95 98 and NT 2 ISDEMO EXE DOS version of ISDEMO program 3 ISDEMOHIP A file which contains help text also reprinted here UNIX version of ISDEMO is currently not available To obtain sample source code for DOS Windows 95 NT or UNIX please contact InterSense 14 3 2 Setting up the Hardware InertiaCube placement The InertiaCube is typically screwed or bolted to the object it is tracking As best as possible locate the InertiaCube level to the ground in relation to its actual position during use o amp Correct Incorrect Optimally you would mount the InertiaCube onto a base plate In cases of anticipated vibration or physical shock it is recommended that rubber mounting pads be used The mounting holes for the InertiaCube are illustrated below 0 11 Diameter The InertiaCube comes with a 10 cable attached This cable plugs into the front panel of the Base Unit The range of the InertiaCube is theoretically unlimited and is only restrained by the length of the cable that attaches it to the Base Unit A length of 10 feet is standard on all orders Lengths above 30 feet have been tested without problem but they are subject to loss of signal strength consult with InterSense 15 Base Unit Set up Make sure the uni
35. e discarded 50 5 2 4 XL mode configuration commands XL System Configuration Hemisphere of Operation MXS Mode lt gt This command is used to specify the type of the auxiliary tracking system attached to the IS 300 Mode 0 None 1 Polhemus Fastrak 2 Ascension Flock of Birds 3 Sagies SM3D Optical Tracker Default 0 MXH Hemisphere lt gt This command sets up the hemisphere of operation of the magnetic tracker IS 300 converts this data to appropriate command and sends it to the magnetic tracker In the case of the optical inertial tracker this command is ignored Hemisphere 0 Forward 1 Aft 2 Upper 3 Lower 4 Left 5 Right Default 0 Source Frame Position and Orientation Optical System Latency MXFh posX posY posZ yaw pitch roll lt gt Source Frame Position and Orientation command is used to specify the orientation and position of the optical tracker in a user defined locally leveled coordinate system Default 0 0 0 0 0 0 Md latency This command sets the latency of the optical data reported to the IS 300 Value is entered in milliseconds Default 20 51 5 3 Records Returned from the Tracker to the Host 5 3 1 Format Considerations Record Headers The first byte of each record is used to identify its type 0 Data record 2 Fastrak status record 3 InterSense manufacturer specific status record Floating Point
36. e perpendicular axes The angular rates are integrated to obtain the orientation yaw pitch and roll of the sensor Gravitometer and compass measurements are used to prevent the accumulation of gyroscopic drift 1 4 InertiaCube integrated inertial instrument The InertiaCube is a monolithic part based on micro electro mechanical systems MEMS technology involving no spinning wheels that might generate noise inertial forces and mechanical failures The InertiaCube simultaneously measures 9 physical properties namely angular rates linear accelerations and magnetic field components along all 3 axes Micro miniature vibrating elements are employed to measure all the angular rate components and linear accelerations with integral electronics and solid state magnetometers The magnetometers are included for optional yaw drift correction in the sourceless inertial orientation mode only The geometry and composition of these elements are proprietary but the functional performance of the multisensor unit can be understood sufficiently by reference to the equivalent diagram in Figure 1 Figure 2 illustrates the basic physical principal underlying all Coriolis vibratory gyros Suppose that the tines of the tuning fork are driven by an electrostatic electromagnetic or piezoelectric drive to oscillate in the plane of the fork When the whole fork is rotated about its axis the tines will experience a Coriolis force F X v pushing them to vibra
37. ed to stabilize the orientation to the earth s gravitational and magnetic fields thus eliminating the gradual but unbounded accumulation of gyroscopic drift errors The Kalman filter uses an ever evolving adaptive algorithm to discard the portion of the accelerometer measurements which are due to actual motion instead of gravity This is a very important step because otherwise horizontal accelerations would result in very large transient pitch and roll errors known as slosh The low cost sourceless trackers used in early consumer HMDs are inclinometer compass devices and are thus intrinsically slosh prone to the point of being uncomfortable to use InertiaCube I Perceptual i Enhancement I I ax y ay az Kalman Filter Algorithm Orientation Error Estimator Figure 3 GEOS mode tracking algorithm In GEOS mode the reference frame hereafter referred to as Navigation frame or Nav frame or N frame is the locally level geographic frame with its x axis pointing north y axis east and z axis down The Euler angles reported by the tracker can be described as a sequence of rotations applied to the InertiaCube starting with its body axes initially aligned with the Nav frame axes and resulting in the current orientation The sequence starts with a rotation by yaw about the Z axis followed by a rotation by pitch about the new Y axis i e body frame axis followed by a rotation by roll about the new X ax
38. emarks are the property of their respective owners Copyright 1999 InterSense Inc 072 00005 0E99 Precautionary Statements r PrP PP Do not attach InertiaCube sensors to the system while the electrical power is applied Any changes or modifications to the IS 300 not expressly approved by InterSense will void the user s authority to operate the equipment Do not drop or otherwise shock the InertiaCube for it can be permanently damaged Do not bend twist pull strongly or tamper in any way with any part of the IS 300 cabling Take care to avoid electric shocks Do not plug in or unplug the power cable with wet hands Please see Appendix D for Health and Safety warnings and guidelines Table of Contents Subject Theory of Operations 1 1 InertiaCube Integrated Inertial Instrument 1 2 Operating Modes 1 2 1 Tracking Modes Overview 1 2 2 3 DOF Gyroscopic Earth stabilized Orientation Sensing GEOS 1 2 8 6 DOF Fusion Mode Specifications and performance characteristics Setting up your new IS 300 3 IS 300 Components 3 2 Setting up the hardware ISDEMO Testing and configuring the IS 300 4 1 Getting started 4 2 File Options 4 3 Communications 4 4 Parameter Options 4 4 1 Tracker System Parameters 4 4 2 Station and Sensor Parameters 4 4 5 XL Tracker Setup 44 4 Setup Position Sensors 4 5 Display Options 4 6 Tools Options 4 7 Window Management Commands under DOS Interface communication p
39. from accumulating Try to keep the area around the system clear and clean Open ports in the rear of the base unit can quickly accumulate dust and dirt that can affect their functioning Recommended cleaning materials are the same as those for computers Antistatic cloths which not only clean the components but also reduce static electricity Cleaning solutions should be applied to the cloth and not directly on ant part of the system components Phone amp email support Any questions regarding the care and maintenance of your IS 300 IS 600 XL can be handled by phone 781 270 0090 or by email info isense com Please see the Support page at www isense com for the technical support contact information Returns to InterSense Should you need to return any component of your system to InterSense for replacement or repair contact InterSense prior to shipment and when shipping use the following address InterSense Inc 73 Second Avenue Burlington MA 02129 USA Batteries There are no batteries in the IS 300 system Electrical power 12 VDC 8 6W 71 Appendix F Interface Protocol Commands Quick Reference Command Syntax Page Data Record Request P 39 Output mode Cc 39 Alignment Reference Frame Af stationNum Ox Oy Oz Xx Xy Xz Yx Yy Yz 39 Reset Alignment Reference Frame R stationNum lt gt 40 Boresight Reference Angles G stationNum yawref pitchref rollref lt gt 40 Boresight Compatibility Mode MBF Swit
40. he data throughput by minimizing the size of the record 4 4 3 Station and Sensor Parameters The window shown below allows you to configure each station A Station is a position and orientation sensing unit which may consist of 1 InertiaCube and 3 or more optical sensors IS 600 XL optical hybrid can support up to 4 stations Note that performance is reduced as more stations are configured Before any data is displayed in this list the program requests and then attempts to receive the configuration data from the tracker If this fails for any reason an error message is displayed and data in the list may not be reliable Some configuration parameters like prediction are only relevant when an InertiaCube is associated with a station When none are N A not applicable is displayed Station Configuration x Station State InertiaCube Enhancement Sensitivity Compass Prediction 1 P 3 oN 0 None N A N A ta None N A N A None N A N A None N A N A None N A N A None N A N A l e 2 3 4 5 6 7 8 None N A N A Double clicking on the Station line or selecting the Change button will bring up the Station Configuration window where changes can be made 25 Station Configuration window Station ON OFF Compass InertiaCube Number C gt Station On Off ON InertiaCube Assignment al Compass ee Perceptual Enhancement Accuracy Smoothness 2 Sensitivity Level uoc KE Predic
41. heart condition e Persons with a history of epilepsy Take frequent breaks A It is recommended that IS 300 should be used for no more than one hour at a time After that you should take a 15 minute rest break before re use regardless of how you feel If you feel uncomfortable at any time stop using immediately Rest after using A Rest for at least 15 minutes after using IS 300 even if you feel fine and have experienced none of the symptoms described below If you have experienced any undesirable effects or symptoms rest until they are completely gone Do not walk drive ride a bike or operate equipment until you have rested otherwise you risk injury to yourself and others Epilepsy and seizures A A very small part of the population has a condition that may result in epileptic seizures or loss of consciousness If you or anyone in your family has epilepsy or has experienced seizures or loss of consciousness do not use IS 300 without first consulting your physician Persons who have not experienced seizures or loss of consciousness may still have an epileptic condition We recommend that a non user is always present when IS 300 is being used 69 Additional possible risks of harm While tracking technology has been used for many years the range of sensors that are used to calculate positional and angular data continues to develop Over the last twenty years as considerable amount of research has been conducted into possible side
42. ions which is designed to make the output data minimize perceivable errors rather than minimize mean square errors Because the human observer is more sensitive to jitter and drift when still or moving slowly the PEA uses adaptive filtering to preferentially suppress these effects as the head slows down Interestingly the PEA only filters the corrections to orientation made by the error estimator and not the orientation signals themselves Therefore the trade off is increased dynamic error and not increased latency If a head at rest suddenly makes a rapid movement there will be no additional latency imposed by the PEA in the all important head motion to visual feedback sensorimotor loop The Perceptual Enhancement is a constantly evolving family of fuzzy rule based algorithms which have been quite successful in eliminating most perceivable jitter and drift without introducing any latency For information on controlling the PEA see the Perceptual Enhancement Level command in sections 4 4 2 and 5 2 2 1 2 3 6 DOF Fusion Mode The 6 DOF Fusion Mode works like an inertial navigation system with optical measurements used to curtail drift in both position and orientation Figure 9 illustrates the signal flow in this mode The same InertiaCube is used as in GEOS mode but its outputs are processed somewhat differently The angular rate signals are integrated in a direct manner to obtain orientation as with GEOS The linear acceleration signals are used
43. is i e body frame x axis The line from the magnetic field sensor outputs of the InertiaCube to the Kalman filter is a dotted line to indicate that the use of the magnetometers may optionally be disabled The accelerometer measurements are sufficient to correct all the drift in pitch and roll and the geomagnetic compassing function is only used to correct drift in yaw In many fly through applications absolute yaw referenced to magnetic north is not important and relative yaw tracking is sufficient This is the case when the user can turn to face an object or rotate the virtual world to bring that object into view In these situations it may be desirable to turn magnetic yaw compensation off if there are large variations in the direction of magnetic north over the tracking area With the compassing turned off the yaw value will drift a few degrees per minute This drift is too slow to notice while it is happening but the cumulative yaw error may eventually become noticeable if the user is seated in a fixed chair and then it may be necessary to send a Heading Boresight command When yaw compensation mode is disabled the Nav frame axes are aligned instead to pseudo north pseudo east and down where pseudo north is simply the direction the InertiaCube x axis was facing on power up or after a Heading Boresight command The Perceptual Enhancement Algorithm PEA indicated with dotted lines is an option provided for HMD tracking and similar applicat
44. l Enhancement Level Rotational Sensitivity Level Associate InertiaCube with a Station Disassociate InertiaCube from a Station Associate Mobile PSE with a Station Disassociate Mobile PSE from a Station Clear Station Command Apply New Configuration Cancel Configuration Session XL System Configuration Hemisphere of Operation Source Frame Position and Orientation Optical System Latency MT lt gt Sets to milliseconds Mt lt gt Sets to microseconds MZ lt gt MS lt gt MP lt gt MG State Rate lt gt MGP Param lt gt Ms stationNum lt gt MH stationNum State lt gt Mp stationNum Interval lt gt MF stationNum Mode lt gt MOf stationNum Sensitivity Level lt gt MCI stationNum InertiaCube number lt gt MCi stationNum InertiaCube number lt gt MCM stationNum MPSE number xp yp zp xn yn zn IDcode lt gt MCm stationNum MPSE number IDcode MCc stationNum MCe lt gt MCx lt gt MXS Mode lt gt MXH Hemisphere lt gt MXF posX posY posZ yaw pitch roll lt gt Md latency 73 46 46 46 46 46 46 47 47 48 48 48 49 49 49 51 51 51 51 52 52 52 52 Appendix G Index of Terms 1 16 bit binary format See Binary 16 format A Alignment Reference Frame commands record Apply Configuration command ei 50 73 ISDEM O s isset a tenebre nest 30 VS O ERARAS 51 61 ASCII format command a e en a d
45. le the sensor position and orientation are being displayed the cursor will blink and may be hard to follow We recommend you use the keyboard commands instead 37 Interface Communication Protocol For IS 300 firmware version 3 0161 Commands Sent from the Host to the Tracker lt gt Carriage return line feed pair not needed for single character commands CR ASCII value 13 LF ASCII value 10 List of parameters required for command List of optional parameters for command Omitting them results in a query The IS 300 emulates most but not all of the commands in the Polhemus Fastrak protocol thus it is possible to use the IS 300 with most applications without writing new driver code There are also several additional commands added to access some of the advanced features of the IS 300 which do not have any counterpart in the Fastrak protocol 5 1 Standard Fastrak Interface Commands 5 1 1 Supported Fastrak Commands Data Record Request P Output mode C Default Alignment Reference Frame Request a data record from all active stations Only used in polled mode Put in continuous output mode Put in polled output mode Polled mode Af stationNum Ox Oy Oz Xx Xy Xz Yx Yy Yz lt gt Default Sets the coordinate frame with respect to which outputs for that station will be reported The coordinate frame is defined by a set three points Ox Oy Oz defines the origin of the new coordinate sy
46. m the floppy disk to that location xcopy a c isdemo Vs When running DOS version without a mouse use following keys to control window functions Alt F10 causes the active window to be maximized restored Alt F4 generates the window close request Alt F2 causes a redraw in all open windows Alt F1 circulates windows If mouse is available you can also use Alt drag to resize the window on which the mouse button is pressed Important Please note that ISDEMO does not save any tracker parameters to the hard disk of your computer All settings displayed in various configuration screens are requested and received from the tracker every time the screen is displayed All changes are immediately converted to commands sent to the tracker and then confirmed 18 Using the ISDEMO The first screen you ll see is the hardware selection window shown below The program creates a different interface depending on the tracker model selected ISDEMO can detect the tracker model automatically Serial communication must first be established with the tracker to utilize this function Use the Autodetect option in the Communications menu to detect port and baud rate parameters if you have trouble setting them manually E System Initialization ISDEMO Ver 4 05 Commands Communications Help dV INTERSENSE Is 300 Series Configured for 15 600 XL device Is 600 Series Is 900 Series e E 0K S IS 600 XL IS 300 The IS 300 is a 3
47. mal vector In a typical installation optical sensor will point up so the normal vector values will be 0 0 0 0 1 0 IDcode Hardware ID of the PSE It is the number of the optical sensor typically 1 to 24 lt gt CR LF pair 49 Disassociate Mobile PSE from a Station MCm stationNum Mobile PSE number IDcode If the station number PSE number and IDcode are not associated in the current configuration this command is ignored This command does not take effect until explicitly activated by the MCe lt gt command Clear Station Command MCc stationNum lt gt Clears all Mobile PSEs associated with a station If the station number is omitted then all stations are cleared This command does not take effect until explicitly activated by the MCe command Apply New Configuration MCe lt gt This command reconfigures the system with the new InertiaCube and PSE information A Configuration Session is the period during which the station and InertiaCube assignment commands are received and accepted Configuration session starts when the first MC command arrives MC commands are saved but not applied to the system configuration until the MCe lt gt command is received This command executes all MC commands received since the start of the Configuration Session and computes the new system state Cancel Configuration Session MCx Cancel the configuration session command All MC commands received during the session ar
48. ndering loop represents the delay of transmitting the results from the tracker to the host If you use binary data mode and set up the IS 300PRO to only transmit 3 Euler angles using the command O1 4 lt gt then the total number of bytes per record will be 15 which corresponds to 150 bits At a baud rate of 115 200 bits sec this record will take about 1 3 milliseconds to transmit Thus the tightest timing loop illustrated in the first diagram above can be achieved but it should probably not be attempted with any longer output data record format or slower baud rate Configuring Tracker for Genlock The default operation of the tracker is free run That is the tracker performs updates and in continuous mode outputs data records as rapidly as it can Genlock operation causes the tracker to synchronize updates and data record output to an external sync signal or to an internal clock When external Genlock is enabled and a valid sync signal is provided it may take several seconds to stabilize tracking If a valid signal not present the tracker will wait an extra period of time for the signal dropping the update rate to half the sync rate Details are discussed below Connecting Sync Signal First set up the tracker as described in the User Manual For an IS 300 PRO or IS 600 Mark 1 use the external sync accessory available from InterSense Follow instructions supplied with the accessory then plug the accessory into IMU port 4 on the front of the
49. ns and Performance Characteristics Performance Specifications The following performance specifications can be achieved when tracking one station in Fusion Mode Please note that the accuracy of the IS 600 XL depends on the accuracy of the optical tracker Specifications Maximum Angular Rate 1200 sec Angular Resolution 0 02 RMS Angular Accuracy 0 1 RMS Maximum Linear Velocity 15 sec Translation Resolution 0 01 RMS Translation Accuracy 0 1 mm RMS Prediction 0 50ms Number of InertiaCube Sensors up to 4 Number of Optical Sensors up to 8 per station total not to exceed 24 Orientation Update Rate up to 500Hz GEOS Mode only Position Update Rate up to 200Hz Fusion Mode Interface RS 232C with selectable baud rates to 115 200 Protocol Compatible with industry standard protocol FASTRAK Max System Configurations GEOS FUSION 4 orientation only 4 6 DOF stations stations 11 Physical Specifications Power 12 VDC 8 6W Operating Temperature 0 to 50 C 32 F to 122 F Storage Temperature 20 to 70 C 4 F to 158 F InertiaCube Base Unit Sensor Signal Processor Dimensions 1 06 x 1 34 x 1 2 5 08 x 5 25 x 1 5 Weight 2 1 oz 15 oz Cable 10 extendible to 30 NA Block Diagram Optical Tracker 115200 Baud Serial Link to Data In Port Null Modem Cable IS 300 Pro KS Oke OO Ly i Ez Compatibility The InterSense IS 300 is compatible with all industry leading softw
50. on Sending W command will cause all the user configuration information to be lost Put in ASCII output mode Put in Binary output mode F 41 Output record list settings Of stationNum p1 p2 p3 pn lt gt Sets the output data list for stationNum If optional parameters are omitted a data record containing current output list settings for the station is returned Item Description Output Format 0 ASCII space character 1 ASCII byte 1 ASCII CR LF pair 2 ASCII bytes 2 X y Z position coordinates 3 floats 4 yaw pitch and roll Euler angles 3 floats 5 X axis direction cosines 3 floats 6 Y axis direction cosines 3 floats 7 Z axis direction cosines 3 floats 11 orientation quaternion 4 floats 16 stylus switch status always 0 1 byte ASCII or binary 18 X y Z in 16 bit binary format see next page 19 yaw pitch and roll in 16 bit binary format see next page 20 quaternion in 16 bit binary format see next page 21 time stamp in selected time units see section 5 3 2 Default 2 4 1 Data Item 4 Euler Angles The Euler angles are defined as rotations about Z then Y then X in body frame Angles are returned in degrees 42 Data Items 5 6 7 Direction Cosines X axis Y axis and Z axis direction cosines can be used construct a 3x3 rotation matrix xl x2 x3 X direction cosines yl y2 y3 Y direction cosines Zl zz Z direction cosines This matrix can also be constructe
51. r 0 5 Config Hex Char 1 6 Config Hex Char 2 7 8 CR LF To decode each of the Config Hex Characters Config Hex Char 0 Config Hex Char 1 Bit Reserved Meaning WNr Config Hex Char 2 Bit Reserved Reserved Unused Unused Meaning 1 2 Reserved Boresight Compatibility Mode 0 Firmware Version 2 x 1 FASTRAK Time units 0 milliseconds 1 microseconds Unused 57 Manufacturer Station Record This record is sent in response to the Ms stationNum lt gt command It returns a station status record specific to the InterSense system 3 stationNum s statusRecord lt gt Bytes Explanation Record type 3 Station number Sub Record type s Config Byte 0 Config Byte 1 Config Byte 2 8 CR LF NYDN BWN To decode each of the Config bytes Config Byte 0 Unused Config Byte 1 Corresponds to the Perceptual Enhancement Level Can be 0 1 or 2 The remaining 2 bits are reserved for future expansion of this option Config Byte 2 Bit Meaning 0 Reserved 1 Heading Compensation Mode bit 1 2 Heading Compensation Mode bit 2 3 Reserved InertiaCube Record Heading compensation bits are translated as 00 Compass mode 0 compass is off 01 Compass mode 1 Partial compass mode 10 Compass mode 2 Full compass mode This record is sent in response to the MCI station number lt gt command It returns the number of the InertiaCube currently associated with this sta
52. r Matlab you must set the output format to ASCII of use the ASCII Flat file option You can display previously recorded data through ISDEMO by selecting Play Playback option will only work on files saved with the As Is ISDEMO Version Hardware Version Firmware Version Communications Output Mode Output Units Output Format Time Units Boresight Mode Sensor 1 Compass InertiaCube 4 05 Is 600 XL 3 0171 v2 COM1 115200 Baud POLLED CENTIMETERS ASCII MILLISECONDS Firmware v2 x Compatible ON Full e option E Data Capture Playback Utility Commands Options Flat File y Flat File 36 Help Facility Help in the ISDEMO is context sensitive Selecting Help or pressing F1 will bring up the appropriate help subject 4 7 Window Management Commands under DOS The DOS version of ISDEMO does not have all the window management functionality of the Windows version Alt F10 Causes the active window to be maximized restored Alt F4 Generates the window close request Alt F2 Causes a redraw in all open windows Alt F1 Circulates windows Alt drag Is used to resize the window on which the mouse button is pressed To move a window hold down the left mouse button over the window header and drag same as in Windows Shortcut Keys F10 Activate menu same as ALT key in Windows Ctrl Q_ Closes current window Ctrl D Start displaying sensor data Ctrl X Stop displaying sensor data Whi
53. riptions 1 2 4 Tracking Modes Overview For a motion tracking system a station means an output data stream corresponding to one particular rigid object being tracked Some manufacturers refer to such a data channel as a sensor which is perhaps more intuitive for a tracking system in which one physical sensor unit is always used to track one moving object However for an IS 600 XL tracking in a 6 DOF mode it is necessary to attach multiple physical sensing devices an InertiaCube and 3 or more optical sensors to a single tracked entity We therefore prefer the term station to reduce confusion For an IS 600 XL each station may be configured in one of the three tracking modes described below Which tracking mode will be used for a particular station depends on what hardware devices are assigned to that station Hardware Assigned to Station Resulting Tracking Mode 1 InertiaCube GEOS mode 3 DOF orientation tracking 1 InertiaCube AND 3 or more Optical 6 DOF Fusion mode Sensors Table 1 Hardware assignments for each tracking mode 1 2 2 3 DOF Gyroscopic Earth stabilized Orientation Sensing GEOS algorithms Figure 3 shows the processing which is used to compute orientation using this sensor configuration The basic computation of orientation from gyroscopic angular rates in the top line of boxes provides the very rapid dynamic response and high resolution of the system The accelerometers and magnetometers are us
54. rotocol 5 1 FASTRAK commands 5 1 1 Supported Fastrak Commands FASTRAK isa registered trademark of Polhemus Inc 13 15 18 21 23 24 24 25 28 29 31 33 37 38 38 Qn fo 0 5 5 2 InterSense specific commands 5 2 1 System Configuration Commands 5 2 2 InterSense specific Station Parameters 5 2 2 Station Components Configuration Commands 5 2 4 XL mode configuration commands 5 3 Records returned from the tracker to the host 5 3 1 Format Considerations 5 3 2 Fastrak System and Data Records 5 3 3 InterSense specific Records 5 3 4 XL System Configuration Records Appendices Genlock Synchronization Frequently Asked Questions FAQ Troubleshooting Health and Safety warnings and guidelines Care and Maintenance Interface Protocol Commands Quick Reference Index of Terms 45 45 46 48 51 52 52 53 57 61 62 66 68 69 71 72 74 Theory of Operations Congratulations for buying the finest orientation tracker on the market This technology offers you several advantages Very low latency Unlimited range Prediction based on directly sensed motion derivatives Smooth jitter free tracking The IS 300 is an inertial 3 DOF Degree of Freedom orientation tracking system It obtains its primary motion sensing using a miniature solid state inertial measurement unit called an InertiaCube which senses angular rate of rotation gravity and earth magnetic field along thre
55. rrect port settings use autodetect for Com parameters Not using Start Displaying Data It may be necessary to select Stop Displaying Data first At least one of the following must be turned on under the Display Menu Numeric Display Display Sensor Check for the following 1 2 3 The InertiaCube is not plugged in The InertiaCube was plugged in after power up Selecting the wrong Sensor Check for the following 1 1 2 Placement directly on top of metal You should place the InertiaCube an inch or two away Make sure that InertiaCube is properly plugged in Keep InertiaCube still while the tracker is booting up or after reconfiguring it 68 Appendix D Health and Safety warnings and guidelines Important Most of the side effects described in this section usually only occur when a tracking device like an IS 300 is used with personal displays or 3D glasses The symptoms listed below are usually referred to as Simulator Sickness Before using IS 300 read and follow the user instructions In exceptional circumstances failure to read and follow the user instructions could result in possible side effects that may lead to accidental injury during or after use Read and follow the user instructions Recommended A For use only by persons 15 years of age or older This system should not be used by e Persons under the influence of drugs and alcohol e Pregnant women e Persons suffering from a
56. sight B stationNum lt gt Fastrak compatibility mode MB stationNum lt gt Firmware Version 2 x compatibility mode Boresight a station If boresight reference angles have been specified by the G stationNum yawref pitchref rollref command prior to issuing of Boresight command then that orientation becomes the new reference point The angles output by the tracker at that orientation become zero Otherwise system uses current station orientation and that becomes the new reference line of sight Please make sure that the object being tracked like an HMD is leveled and is pointing down the x axis when boresighting a station b stationNum lt gt Fastrak compatibility mode Mb stationNum lt gt Firmware Version 2 x compatibility mode Unboresight a station Reference angles are cleared for the specified station B stationNum lt gt Firmware Version 2 x compatibility mode MB stationNum lt gt Fastrak compatibility mode This command is used to define a user coordinate frame for orientation It only applies to GEOS mode stations In GEOS mode the default orientation reference frame is a locally level geographic frame with its x axis pointing towards local magnetic north if the compass is on or towards the direction the InertiaCube was facing at power up if the compass is off This command takes the current heading and makes it the new direction of the x axis The yaw value at that point becomes zero
57. simultaneously for two separate purposes First they are transformed from the InertiaCube body frame B frame into a locally level navigation frame N frame The gravitation constant g is then subtracted from the vertical acceleration component in order to cancel the unwanted effects of gravity on the accelerometer triad Then the remaining acceleration vector is double integrated to track changes in the N frame position In a second usage the B frame accelerations are also fed into the error estimator to help cancel pitch and roll drift analogous to the way they are used in GEOS mode Orientation Orientation Integration Prediction aCe es amp PEA Coordinate g LI Double Position Transform gravity Integration Prediction amp PEA Optical Position Measurements X Y Z EKF Orientation and Position Error Estimator Figure 9 Fusion Mode tracking algorithm Position and orientation drift correction is computed based on the optical system measurements As shown in Table 1 a Fusion Mode station must be equipped with an InertiaCube and 3 or more optical sensors These components are mounted on a rigid object to be tracked and then the position of the optical sensors with respect to the B frame axes of the InertiaCube are measured and entered into the tracker The origin and axes of the tracked station for the purposes of tracking will be those of the InertiaCube 10 Specificatio
58. sing ISDEMO using the K command or using the LCD if equipped 64 Enabling Genlock via LCD Menu available on IS 600 Mark 2 and 1S 900 CT Select Communication Data Output Sample Mode Continuous to place the tracker in continuous mode If the tracker is used in polled mode its internal updates will be synchronized to the sync signal but data record output will not Select System Config Genlock State and then one of the following choices Off Genlock off Auto Use external sync autodetect strobe rate minimum 30 Hz Manual Use external sync select strobe rate in 5 Hz increments using arrow buttons then press the enter button Internal Use internal sync select data record output rate in 5 Hz increments using arrows buttons then press the enter button Verifying Synchronization To verify Genlock is working with an IS 600 Mark 2 or IS 900 CT check the Genlock indicator in the lower right corner of the LCD on the front panel of the base unit When Genlock is on and stable the indicator displays G otherwise the indicator is blank To verify Genlock is working with an IS 300 PRO or IS 600 Mark 1 display tracking statistics in ISDEMO Tools menu of ISDEMO 4 03 or later and check the update rate If the tracker is synchronized the update rate will equal or be a multiple of rate If state is 2 and the sync signal is not detected by the tracker due to an invalid signal or incorrect configuration the update rate will be
59. sor is assigned to PSE number is the index of the PSE within a station numbers 1 to 8 are accepted Hardware ID is the optical sensor identifier values 1 to 24 are accepted When finished entering data press Apply Mobile PSE Data x Commands Station Pse Number sash ee a 0 0804 Normal Y Jo spei Hardware ID 30 4 5 Display Options ISDEMO Configured for 1S 600 XL device File Communications Parameters 32 68Kbps 70 Records s 203 Frames s Station 1 ON Display is ON Start and Stop Displaying Data Station Number To display position and orientation data being received from the tracker use the Start Displaying Data option in the Display menu or press Ctrl D ISDEMO first attempts to establish communication and get all configuration information necessary to correctly interpret and display incoming data If it fails to receive a reply to any of the status record requests it will still go into the display mode but there may be no data to display or it may not be able to display the data correctly If such errors are detected stop the display by selecting Stop Displaying Data option in the Display menu or pressing Ctrl X and check the connection Allows you to choose which station is to be displayed 31 Display Text Numeric Display Synchronize to monitor When this option is selected all status and some of the data records are displayed in text format in the sensor display are
60. stem Xx Xy Xz defines a point on the positive x axis and Yx Yy Yz defines a point on the positive y axis If optional parameters are omitted current values are returned X North Y East Z Down position origin is not relevant 38 Reset Alignment Reference Frame Boresight Reference Angles Boresight Compatibility Mode R stationNum lt gt Resets reference frame to the default G stationNum yawref pitchref rollref lt gt Default MBF lt gt MBI lt gt Default Sets the boresight reference angles for the specified station If set these values are then used by the next Boresight command instead of current orientation If optional parameters are omitted current reference angles are returned 0 0 0 Switch system to Fastrak Compatible mode Switch system to Firmware Version 2 x Compatible mode In firmware versions prior to 3 00 the B stationNum lt gt command was implemented as the Heading Boresight see below and full boresight was not available To maintain compatibility with the user software written at that time two Boresight Compatibility modes are available In Fastrak Compatible mode B stationNum lt gt command executes full 3 DOF boresight and MB stationNum lt gt affects heading only In the Firmware Version 2 x Compatible mode the meanings of these commands are reversed Firmware Version 2 x Compatible 39 Boresight Unboresight Heading Boresight Heading Unbore
61. t it turned off before connecting any cables Connect the InertiaCube s to the front of the Base Unit Plug in the power cord Connect the RS232 cable between the Base Unit and the Host Computer Select baud rate using mode switch as described below Connect the optional optical tracker to the Data In port of the IS 300 7 Turn on the optional optical tracker tat ot ea NM Set the power mode switch to on The power on LED on the front panel will turn on The four IS 300 Pro LED lights on the front panel of the Base Unit to the left of the InertiaCube plug in locations will flash in sequence for a few seconds then stop Each LED corresponds to the InertiaCube plug in pattern to the right i e upper right hand LED is for the upper right hand InertiaCube plug in 4 When a particular InertiaCube is in motion the corresponding LED will flash to acknowledge this IS 300 single sensor tracker has only one sensor connector and one LED Baud Rate The Base Unit has a switch located on the back of the unit This gives you the option of choosing one of four baud rates 9 600 mode 0 19 200 mode 1 these correspond to the 38 400 mode 2 mode switch at last 115 200 mode 3 power up Note you must power cycle the system power down power up after changing the mode 16 Tracker Use Guidelines e Keep the InertiaCube s still 1 e sitting on a table for the entire boot up period whenever the tracker configur
62. tationNum lt gt are maintained turning compass mode to 2 and 0 respectively Default 2 Note These settings are only used if station is configured for GEOS Mode operation Compass readings are not used for tracking in Fusion Mode 46 Prediction Interval Mp stationNum interval lt gt Sets the time interval of prediction for stationNum Interval is an integer number of time in milliseconds Suggested range is 0 50ms If optional parameter is omitted current prediction value is returned Default 0 Perceptual Enhancement Level MF stationNum Mode lt gt In order to provide the best performance for a large range of various applications 3 levels of perceptual enhancement are available None of the modes introduces any additional latency Mode 0 provides the best accuracy The drift correction adjustments are made immediately no jitter reduction algorithms are used This results in somewhat jumpy output not recommended for head tracking but with lower RMS error Use this mode for accuracy testing or for any application which requires best accuracy Mode 1 provides accuracy similar to that of mode 0 with an addition of a jitter reduction algorithm This algorithm reduces the accuracy by only a small amount and does not add any latency to the measurements Mode 2 is recommended for use with HMD or other immersive applications The drift correction adjustments are made smoothly and only while the sensor is moving
63. te perpendicular to the plane of the fork The amplitude of this out of plane vibration is proportional to the input angular rate and it is sensed by capacitive or inductive or piezoelectric means to measure the angular rate By way of comparison a conventional inertial measurement unit IMU senses 6 of these properties using 6 separate instruments 3 rate gyros and 3 linear accelerometers each of which by itself would typically be larger heavier and more expensive than an InertiaCube Unlike conventional rate gyro and accelerometer instruments which must be carefully aligned on a driven vibration 4 Q 1 Y sensed vibration X gyro E Q Xv Z gyro y gyro y accel y mag ae z accel angular rate z mag Figure 1 Functional diagram of InertiaCube Figure 2 Principle of Coriolis vibratory Gyroscope precision machined triaxial mounting block the InertiaCube is a monolithic device with its orthogonal outputs factory calibrated to precise alignment Being a digital device the InertiaCube cabling and connectorization is relatively non critical and the cables can be extended up to 30 feet without fear of contaminating sensitive analog signals The power consumption of the InertiaCube is 30 mA at 9V which makes it suitable for prolonged operation from a small battery in future wireless applications Figure 3 shows an InertiaCube next to a floppy disk for scale Figure 3 InertiaCube 1 2 Operating Mode Desc
64. the value with the arrow buttons then press the enter button To increase or decrease to the next or previous phase point select System Config GenlockPhase Increase or Decrease Adjust the phase to the latest point in the cycle for minimum latency such that the system still behaves smoothly during head rotation no render cycles last beyond the deadline for the next scan out 65 Ql Q2 Q3 Q4 Q5 Q6 Appendix B Frequently Asked Questions What is the maximum length of the cable between the InertiaCube and the Base Unit The cable between the InertiaCube and the Base Unit has been tested to a length of 30 feet Longer than 30 feet will result in loss of signal strength Does the InertiaCube have batteries How often do they have to be changed The InertiaCubes do not contain batteries Are all the interconnection cables shielded YES What is the MTBF of each component separately Based on supplier data the MTBF for the system is estimated at 5 years What type of shock can the InertiaCube sustain These InertiaCube is designed to withstand a maximum acceleration of 500 g Basically this means that a direct impact on the devices is not recommended The InertiaCubes can withstand a higher level of shock if installed on the inside of an object or mounted on rubber What are the PIN assignments on the DB9 on the IS 300 Pin Function 1 DCD 2 RX 3 TX 4 DTR 5 GND 6 DSR 7 RTS 8 CTS 9 RI
65. ting in no visual glitch Of course if there are several frames in a row that run longer than 16 7 ms the system will eventually drop a frame resulting in a jarring transition to 2 24 frame latency To prevent this the application developer must insure that the average frame rate before attempting synchronization is ALWAYS above 60 Hz so that once the synchronization is turned on the frame rate will be fixed at 60 Hz with no annoying shifts As a precaution in case there ever is a time when the frame rate of the rendering engine drops below 60 Hz the SW driver which is reading data from the tracker should always check to make sure that it is reading the latest available data record After reading a complete record check to see if there are any further bytes in the receive buffer and if so wait for there to be a complete record and read it in replacing the just read record If this is not done multiple data records could become queued up in the receive buffer resulting in lots of extra latency time ms 0 16 7 33 3 50 scan out rendering tracking MEE mmm CRM CHM NEN NNNM SEN CHEE CENE CORN o CEE ON 12 34 56 78 P peu first second processing processing stage stage sample TnertiaCuhe A second reason why you may want to adjust the output record transmission to an earlier phase point is to allow for serial port transmission time In the diagrams above the slant of the arrow pointing up from the tracking loop to the re
66. tion 3 station number I InertiaCube number lt gt Bytes Explanation 1 Record type 3 2 Station Number 3 Sub Record type T 4 5 InertiaCube number 1 4 or 1 if none are associated 6 7 CR LF 58 Prediction Interval Record Sensitivity Level Record Mobile PSE Record This record is sent in response to Mp stationNum lt gt command It returns an ASCII integer for the number of milliseconds of prediction 3 stationNum p interval lt gt Bytes Explanation 1 Record type 3 2 Station Number 3 Sub Record type p 4 Prediction interval 5 6 CR LF This record is sent in response to MQf station number command It returns the current sensitivity settings of a station This setting is only relevant when Perceptual Enhancement level is 2 3 Station Number Q Sensitivity Level Bytes Explanation 1 Record type 3 2 Station Number 3 Sub Record type Q 4 Sensitivity level 1 to 4 5 6 CR LF Sent in response to MCM station number PSE number lt gt command It returns the current settings of a station or a single PSE within station 3 Station Number M Mobile PSE number Mobile PSE record Bytes Explanation 1 Record type 3 2 Station Number A hexadecimal number up to C 3 Sub Record type M 4 10 Mobile PSE number 11 40 X y z components of position vector in 0 4f ASCII format Values are in meters 41 61 X y Z components of normal vector in 7
67. tion Value uc KE When a station is ON a data record will be sent for it even if there is no InertiaCube or optical sensors are assigned to it This controls the state of the compass component of the InertiaCube Compass is only used when station is configured for GEOS mode in Fused mode compass readings are not used regardless of this setting When station is configured for FULL compass mode the readings produced by the magnetometers inside the InertiaCube are used as absolute reference orientation for yaw Compass can be affected by metallic objects and electronic equipment in close proximity to the InertiaCube When station is configured for PARTIAL compass mode magnetometer readings are used to reduce drift and maintain stability but not as an absolute measurement system In this mode system is much less susceptible to magnetic interference but heading drift will accumulate If compass is OFF no heading compensation is applied See section 5 2 2 InterSense specific Station Parameters for more details InterSense trackers support up to 4 InertiaCubes Optical inertial hybrid must have and InertiaCube assigned to each station Perceptual Enhancement Level In order to provide the best performance for a large range of various applications three levels of perceptual enhancement are available None of the modes introduces any additional latency 26 Sensitivity Level Prediction Value Commands sub menu Refresh Status
68. y Settings System Initialization window also seen at initial start up is shown when Select Hardware Device is selected Use this window to select or detect the tracker model connected to your computer Sends K command to the tracker This saves the current settings to nonvolatile memory in the tracker base unit The next time the tracker is turned on these settings will be restored 21 Load Power Up Settings Sends Y commands to the tracker This restores the firmware to the power up condition All changes made to the settings since power up or last K command are lost Load and Save Factory Settings Sends W command to the tracker This restores the system settings to the factory defaults Boresight Current Station Sends B stationNum lt gt command to the tracker where stationNum is the number of the currently displayed station Please see section 4 2 9 for instructions on how to switch between stations Please see chapter 6 for complete explanation of the boresight implementation Unboresight Current Station Sends b stationNum lt gt command to the tracker This reverses the effects of boresight command 22 4 5 Communications options This menu allows you to set the communications port and the baud rate of the computer ISDEMO is running on to match the settings of the tracker Communications Port Baud Rate Autodetect Parameters Bii ISDEMO Configured 600 Series device Parame 78 84Kbps 272 Records s
69. ynchronization is essential if smooth response is desired during periods of moderately fast head rotation GEOSTM mode runs several times faster on IS 300 PRO 600 or 900 series products and therefore the need for Genlock is less dramatic Nonetheless for very high performance systems it is still beneficial to use it in GEOS mode and therefore a Genlock adapter accessory is being developed for the IS 300 PRO which allows users to obtain synchronization signals from NTSC VGA or TTL sources and feed them in through the unused 4 InertiaCube input port on the IS 300 PRO or the IS 600 Mark 1 When using an IS 600 or IS 900 with StereoGraphics CrystalEyes Genlock synchronization is also used to prevent the infrared signals emitted by the ReceiverPods from interfering with the infrared receiver in the CrystalEyes eyewear Timing Diagram IS 300 PRO interfaced to PC with 60 Hz display refresh time ms 0 16 7 33 3 50 0 scan out latency es i ij 1 Es Es rendering m tracking EEH EEE CHM CHM NEN onn CREE onn CREE CEN ONE CEU CUN 12 34 56 78 Pn sample first second InertiaCube processing processing stage stage 62 This diagram illustrates the timing relationship of the tracking loop to the rendering loop with Genlock in effect The vertical lines at multiples of 16 7 milliseconds represent the vertical sync pulses stripped from the 60 Hz VGA monitor cable The tracker automatically determines the frequency of the Genlock syn
70. ype 3 2 Station Number Always 1 3 4 Sub Record type XH 5 Hemisphere 0 Forward 1 Aft 2 Upper 3 Lower 4 Left 6 7 CR LF Sent in response to MXF lt gt command It returns the current settings of the source frame parameters Bytes Explanation 1 Record type 3 2 Station Number Always 1 3 4 Sub Record type XF 5 34 posX posY posZ in 0 3f format 35 55 yaw pitch roll in 7 3f format 56 57 CR LF 61 Appendix A Genlock Synchronization Last updated 01 28 99 Applicable products IS 300 PRO with Genlock adapter accessory IS 600 Mark 1 with Genlock adapter accessory IS 600 Mark 2 IS 900 CT Purpose Genlock synchronization is used to guarantee constant latency between the sampling of the motion tracking sensor and the scan out of the updated image on the display device Any jitter in the amount of latency will appear as jitter in orientation when the head is rotating For typical head rotation rates of 300 degrees sec a timing jitter of 6 7 milliseconds will result in orientation jitter of 2 degrees which is highly disturbing On an IS 600 or 900 series product running Fusion mode with no synchronization the tracker will update at about 150 Hz corresponding to a 6 7 ms period Since the 150 Hz update rate of the tracker is asynchronous with the update rate of the computer graphics rendering and display cycle the latency will vary by up to 6 7 ms from cycle to cycle and thus Genlock s

Download Pdf Manuals

Related Search

Related Contents

2013 Nissan Maxima Owners Manual  SERVICE  Adobe Illustrator 8 Shading Procset  Mercedes-Benz 2006 SLR Unlimited Automobile User Manual  fonds bijouterie Jeannot  Earth Centered Universe Lite Manual V3.2A  Elite-x Series Operation Manual  Untitled - Topaz Labs  

Copyright © All rights reserved. Failed to retrieve file