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1. Move source destination size bytes Move copies the specified nunber of bytes fromthe source pointer to the destination pointer Store the pitch Move Ai dat al pntr amp pitch si zeof pitch increase the pointer to point to the next data el erent type pntr sizeof pitch br eak case ConmPr ot ocol kRol Move source destination size bytes Move copies the specified nunber of bytes fromthe source pointer to the destination pointer Store the roll Move amp data pntr Sr oll si zeof roll increase the pointer to point to the next data element type pntr sizeof roll br eak case ConmPr ot ocol kTenper at ure Move source destination size bytes Move copies the specified nunber of bytes fromthe source pointer to the destination pointer Store the headi ng Move A dat alL pntr amp t emper at ure si zeof t enperature increase the pointer to point to the next data element type pntr si zeof temper at ur e br eak PNI Sensor Corporation DOC 1018154 r01 SeaTRAX User Manual October 2012 Page 67 default Message is a function that displays a formatted string simlar to printf Wessage Unknown type W2X r n data pntr 1 unknown data type so size is unknown so skip ever yt hi ng return br eak count Qne less element to read in Message is a function that displays a formatted string
2. Ul nt 16 CommPr ot ocol CRO void data Ul nt 32 en Ulnt8 dataPtr Unt8 data Ul nt 32 index 0 Ulnt16 cre 0 while len crc unsigned char crc gt gt 8 crc lt lt 8 crc dat aPtr i ndex crc unsigned char crc 8 Oxff gt gt 4 crc crc lt lt 8 lt lt 4 crc cre amp Oxff lt lt 4 lt lt 1 return crc ig This is called each time this process gets a turn to execute voi d Conmpr ot ocol Cont rol Inten returns the number of bytes in the input buffer of the serial object that are available for us to read Ul nt 32 i nLen n eri al Port gt I nLen SeaTRAX User Manual r01 Page 62 swi t ch mot ep case 1 wait for length bytes to be received by the serial obj ect if inLen gt 2 Read block wl return the number of requested or available bytes that are in the serial objects input buffer read the byte count ner i al Port gt ReadBl ock m nDat a 2 TT TT byte count is ALWAYS transmtted in big endian copy byte count to mExpectedLen to native endi aness mExpectedLen mnData 0 lt lt 8 m nDat al 1 Ticks is a timer function 1 tick 10msec wait up to 1 2s for the complete frame mExpectedLen to be received mii me Ticks 50 nSt ep goto the next step in the process break case 2 wait for msg complete or timeout if inLen gt
3. simlar to printf Wessage Headi ng Pitch Poll Temperature r n heading pitch roll temperature m6t ep send next data request br eak default Message is a function that displays a formatted string simlar to printf Wessage Unknown frame 02X recei ved r n Ul nt 16 f rameType br eak Have the ConmProtocol build and send the frame to the nodule TT voi d SEATRAX SendConm Ul nt 8 frameType void dataPtr Ulnt16 dat aLen if mConm nConm gt SendDat a frameType dataPtr dat aLen Ticks is a timer function 1 tick 10msec mResponseTi me Ticks 300 Expect a response w thin 3 seconds This is called each time this process gets a turn to execute id SEATRAX Cont rol t ch n6t ep i 0 TE gt gt Die case 1 Ul nt8 pkt kDat aCount 1 the coments we are requesting preceded by the number of components bei ng request ed pkt 0 kDat aCount SeaTRAX User Manual r01 Page 68 pkt 1 ConmPr ot ocol kHeadi ng pkt 2 ConmProtocol kPitch pkt 3 ConmPr ot ocol kRol pkt 4 ConmPr ot ocol kTenper at ure SendConm ConmPr ot ocol kSet Dat aComponents pkt kDat aCount 1 Ticks is a timer function 1 tick 10msec mii me Ticks 100 Taking a sample in ts m6t ep go to next step of process br eak case 2 Ticks is a timer function 1 t
4. 31 24 23 1615 87 0 msb Isb Big Endian 7 015 8 23 1631 24 Isb msb Little Endian Unsigned 16 Bit Integer Ulnt16 UInt16 based parameters are unsigned 16 bit numbers 15 87 0 7 0 15 8 msb Isb Isb msb Big Endian Little Endian Unsigned 8 Bit Integer Ulnt8 UInt8 based parameters are unsigned 8 bit numbers SeaTRAX User Manual r01 Page 36 byte Boolean Boolean is a 1 byte parameter that MUST have the value 0 FALSE or 1 TRUE 7 0 byte 7 3 Commands 8 Communication Frames Table 7 2 SeaTRAX Command Set Frame IDa Command Description 1 7 kGetModInfo Queries the device s type and firmware revision 2 kGetModInfoResp Response to kKGetModInfo 6 kSetConfig Sets internal configurations in SeaTRAX 19 kSetConfigDone Response to kSetConfig 7 kGetConfig Queries SeaT RAX for the current internal configuration 8 kGetConfigResp Response to kGetConfig 42 kSetFIRFilters Sets the FIR filter settings for the magnetometer amp accelerometer sensors 20 kSetFIRFiltersDone Response to kSetFIRFilters 13 kGetFIRFilters Queries for the FIR filter settings for the magnetometer 8 accelerometer sensors 14 kGetFIRFiltersResp Contains the FIR filter settings for the magnetometer amp accelerometer sensors 46 kSetSyncMode Sets whether the Sea TRAX is in normal or Sync Mode 47 kSetSyncModeResp Response to kSetS
5. Table 5 4 12 Point Limited Tilt Calibration Pattern Sample Yaw Pitch Roll First Circle 1 0 0 0 2 90 0 0 3 180 0 0 6 270 0 0 Second Circle 7 45 gt 52 gt 50 8 135 gt 50 gt 50 11 225 gt 52 gt 50 12 315 gt 5 gt 50 Third Circle 13 45 lt 5 lt 5 14 135 lt 5 lt 5 17 225 lt 5 lt 5 18 315 lt 5 lt 5 PNI Sensor Corporation SeaTRAX User Manual October 2012 DOC 1018154 r01 Page 15 Note that a similar and acceptable alternative pattern would be to follow he recommended 12 point Full Range Calibration pattern but substituting the gt 45 of pitch with whatever pitch can be achieved and the 30 to 40 or roll with whatever roll can be achieved up to these limits See Section 5 1 1 5 1 4 Hard Iron Only Calibration It is not uncommon for the hard iron magnetic distortions around the SeaTRAX to change Some reasons for this include significant temperature change or temperature shock to a system as well as gradual aging of components A Hard Iron Only Calibration allows for quick recalibration of the SeaTRAX for hard iron effects and generally is effective for operation and calibration in the tilt range of 3 or more 245 is preferred The recommended 6 point calibration pattern given below is a circle of alternately tilted evenly spaced points with as much
6. PNI calibrates the accelerometers in its factory prior to shipment But over time the bias and offset of the accelerometers will drift For this reason PNI recommends the accelerometers be recalibrated every 6 to 12 months The user may return the SeaTRAX to PNI for accelerometer calibration or the user may perform a user accelerometer calibration The remainder of this section covers the user accelerometer calibration 5 2 1 Accelerometer Only Calibration The requirements for a good user accelerometer calibration differ significantly from the requirements for a good magnetic calibration Specifically a good accelerometer calibration involves the SeaTRAX experiencing a wide range of pitch and roll values preferably seeing both 180 of pitch and 180 of roll Also it is necessary for the SeaTRAX to be very still during an accelerometer calibration If possible PNI recommends using a fixture to hold the device during calibration although resting the SeaTRAX on a hard surface normally is sufficient On the other hand the Sea TR A X does not need to be incorporated in the user s host system to perform a user accelerometer calibration which significantly simplifies calibration when compared to magnetic calibration Figure 5 2 shows the two basic starting positions for the recommended 18 point calibration pattern Starting with the SeaTRAX as shown on the left in Figure 5 2 rotate the device about its z axis such that it sits on each of its 4
7. Unt 8 frame void dataPtr NULL Ul nt 32 void Set Baud Ul nt 32 baud pr ot ect ed SeaTRAX User Manual r01 CornmHandl er mHandl er Ser Port meri al Port Ul nt 8 mOut Dat al kBuf f er Si ze m nDat al kBuf f er Si ze Ul nt 16 rmExpect edLen Ul nt 32 mut Len nO dl nLen mi me mer ep Ul nt 16 CR void data Ulnt32 len void Control Page 60 7 7 3 CommProtocol cpp File i ncl ude CommPr ot ocol h import an obj ect that wll provide a 10m6ec tick count through a function called Ti cks i ncl ude Ti ckGener at or h II Ber Port is an obj ect that controls the physical serial interface It handles sending out the characters and buffers the characters read in until a we are ready for them CornmPr ot ocol ConmPr ot ocol CommHandl er handler Ser Port serPort Process ConmPr ot ocol mHandl er handler store the obj ect that wll parse the data when it is fully received mSeri al Port ser Port Init Initialize the serial port and variables that wll control this process voi d ConmPr ot ocol I nit Ul nt 32 baud Set Baud baud nA dinLen 0 no data previ ously recei ved mStep 1 4 goto the first step of our process e Put together the frare to send to the module voi d CommPr ot ocol SendDat a Unt 8 frameType void dat abr r Ulnt32 en Ulnt8 data Unt8 dataPtr the data to send Ul nt 32
8. below in Table 4 1 Table 4 1 SEATRAX Pin Descriptions Pin Number Description 1 UART Rx 2 UART Tx 3 Vin 4 GND Footnote 1 Pin 1 is located per Figure 3 1 After making the electrical connections it is a good idea to perform some simple tests to ensure the SeaTRAX is working as expected See Section 5 for how to operate the SeaTRAX with PNI Studio or Section 7 for how to operate the SeaTRAX using the PNI binary protocol 4 2 Installation Location The SeaTRAX s wide dynamic range and sophisticated calibration algorithms allow it to operate in many environments For optimal performance however you should mount the SeaTRAX with the following considerations in mind SeaTRAX User Manual r01 Page 6 4 2 1 Operate within the SeaTRAX s dynamic range The SeaTRAX can be field calibrated to correct for static magnetic fields created by the host system However each axis of the SeaTRAX has a calibrated dynamic range of 125 uT If the total field exceeds this value for any axis the SeaTRAX may not perform to specification When mounting the SeaTRAX consider the effect of any sources of magnetic fields in the host environment that when added to Earth s field may take the SeaTRAX out of its dynamic regime For example large masses of ferrous metals such as transformers and vehicle chassis large electric currents permanent magnets such as electric motors and so on 4 2 2 Locate away from changing magnetic
9. etc batteries audio speakers current carrying wires and electric motors Compensation is accomplished by mounting the SeaTRAX in the host system and performing a user calibration It is expected the sources of magnetic distortion remain fixed relative to the SeaTRAX s position within the host system By performing a calibration the SeaTRAX identifies the local sources of magnetic distortion and negates their effects from the overall reading to provide an accurate heading As with the magnetic sensors the accelerometers in the SeaTRAX are calibrated at PNI s factory But the accelerometers gradually change over time and the user either will need to periodically perform a user accelerometer calibration or return the unit to PNI for recalibration As a rule of thumb the accelerometers should be recalibrated every 6 to 12 months Unlike a magnetic calibration the accelerometers may be calibrated outside the host system Accelerometer calibration is more sensitive to noise or hand jitter than magnetic calibration especially for subsequent use at high tilt angles Because of this a stabilized fixture is suggested for accelerometer calibration although resting the unit against a stable surface often is sufficient Key Points e User calibration is required for the SeaTRAX to perform optimally and meet specification e Magnetometer calibration o Requires incorporating the SeaTRAX into the user s host system such that the magnetic compo
10. mExpectedLen 2 Ul nt 16 crc crcRecei ved calculated and received crcs Read block wl return the nunber of requested or available bytes that are in the serial obj ects input buffer nSer i al Port gt ReadBl ock Amt nDat a 2 SS TT mExpectedLen 2 in CRC verification don t incl ude the CRC in the recal cul ati on 2 crc CRO mnData mExpectedLen 2 CRC is also ALWAYS transmtted in big endian crcRecei ved mnDat al mexpectedLen 2 lt lt 8 m nDat al mexpectedLen 1 if crc crcRecei ved the crc is correct so pass the frame up for processi ng i f mHandl er mHandl er gt Handl eConm m nDat al 2 amp m nDat a 3 mExpectedLen kPacket M n ze el se II crc s don t match so clear everything that is currently in the input buffer since the data is not reliable mer al Port gt l nQ ear PNI Sensor Corporation DOC 1018154 r01 SeaTRAX User Manual October 2012 Page 63 go back to looking for the length bytes mStep 1 el se Ticks is a timer function 1 tick 10msec if Ticks gt mli me Corrupted message W did not get the length we were expecting within 1 2sec of receiving the length bytes ear everything in the input buffer since the data is unreliable nSeri al Port gt l nO ear mStep 1 Look for the next length bytes TT TT break def ault break SeaTRAX User Man
11. AutoSanpling 13 type bool ean kBaudRat e 14 Unt8 kM Out Put 15 type Bool ean kDat aCal 16 type Bool ean kCoef T CopySet 18 18 type Ulnt 32 kAccel Coef f CopySet 19 type Ulnt 32 Mounting Reference I Ds kMount ed andar d 1 1 kMbunt edXUp 11 2 kMbunt ed YUp e kMbunt edSt dPI us90 II 4 kMbunt edSt dPl us180 PS kMbunt edSt dn us270 6 kMount edZDown 7 kMbunt edXUpPI us90 8 kMbunt edXUpPI us 180 9 kMbunt edXUpPI us270 10 kMbunt ed YUpPI us90 G 11 PNI Sensor Corporation DOC 1018154 r01 SeaTRAX User Manual October 2012 Page 57 kMbunt edYUpPI us180 kMount ed YUpPI us270 kMWMbunt edZDownPl us90 kMount edZDownPl us180 kMount edZDownPl us270 Result kErr None kErr Save e Ul n o TT _ Ds 0 Taa o 0 function to cal cul ate CRC 16 t16 CO void data Ulnt32 en Ulnt8 dataPtr Unt8 data Ul nt 32 index 0 Update the CRC for transmtted and received data using the CCITT 16bit algorithm X 16 X12 X5 1 Ulnti6 crc 0 while len crc unsigned char crc gt gt 8 crc lt lt 8 crc dat aPtr i ndex 4 crc unsigned char crc 8 Oxff gt gt 4 crc cre lt lt 8 lt lt 4 crc cre 8 Oxff lt lt 4 lt lt 1 return crc SeaTRAX User Manual r01 Page 58 7 7 2 CommProtocol h File pr agma once i ncl ude Syst enfe
12. D nas D D D D D D D D D Tiana D D D ee GO J O Q GOM GO SeaTRAX User Manual r01 Page 56 kGet AcqPar amsResp kPower DoneDown kFact or yUser Cal kFact or y User Cal Done kTakeUser Cal Sanpl e kFactorylncl Cal 36 kFact or yl ncl Cal Done kSet SyncMode 46 kSet SyncModeDone kSyncRead 49 Cal Option IDs o D D D D D KT D D D D D D D D kFul RangeCal 10 10 type Fl oat 32 k2DCal 20 20 type Fl oat 32 KH Onl yCal 30 30 type Fl oat 32 kLimtedTiltCal 40 40 type Fl oat 32 kAccel Cal Onl y 100 100 type Fl oat 32 kAccel Cal wi t hMag 110 110 type Fl oat 32 Param Ds kSet Dat aConponents 3 3 Axisl D U nt 81 Count Unt8 Value Float64 Data Component Ds kHeadi ng 5 5 type FI oat 32 kTenper ature 7 7 type Fl oat 32 kDi st orti on 8 type bool ean kAccel X 21 21 type Fl oat 32 kAccel Y 22 type Fl oat 32 kAccel Z 23 type Fl oat 32 kPi t ch 24 type Fl oat 32 kRol l 25 type Fl oat 32 kMagX 27 11 27 type Fl oat 32 kMagY 28 type Fl oat 32 kMagZ 29 type Fl oat 32 Configuration Parameter Ds kDecli nation 1 1 type FI oat 32 kTr ueNor t h 2 type bool ean kMounti ngRef 10 10 type Ulnt8 kUser Cal St abl eCheck 11 type bool ean kUser Cal NunPoi nt s 12 type Ul nt 32 kUser Cal
13. Hard iron distortions add a constant magnitude field component along each axis of sensor output Soft Iron Effects Soft iron distortions are the result of interactions between the Earth s magnetic field and any magnetically soft material within close proximity to the sensors In technical terms soft materials have a high permeability The permeability of a given material is a measure of how well it serves as a path for magnetic lines of force relative to air which has an assigned permeability of one Unlike hard iron distortion soft iron distortion changes as the host system s orientation changes making it more difficult to compensate Temperature Effects While the hard iron and soft iron distortions of a given component in a system may remain quite stable over time normally this distortion signature will change over temperature Therefore no matter how stable a heading sensor is over temperature it is usually necessary to recalibrate as the temperature changes since the magnetic distortion signature of the host system will change over temperature One way the SeaTRAX helps with this issue is by allowing the user to save up to 8 sets of calibration coefficients so that as the temperature changes a magnetic calibration coefficient set matching the new temperature can be used in the SeaTRAX Other Considerations The SeaTRAX measures the total magnetic field within its vicinity and this is a combination of Earth s magnetic
14. ID4 Format Values Range Default kDeclination 1 Float32 180 to 4180 0 kTrueNorth 2 Boolean True or False False kBigEndian 6 Boolean True or False True 1 STD 0 2 X UP 0 Sea HIS GIS 4 STD 90 5 STD 180 6 STD 270 7 Z DOWN 0 8 X UP 90 9 X UP 180 10 X UP 270 11 Y UP 90 12 Y UP 180 13 Y UP 270 14 Z DOWN 90 15 Z DOWN 180 16 Z DOWN 270 kUserCalNumPoints 12 Ulnt32 4 32 12 kUserCalAutoSampling 12 Boolean True or False True kMountingRef 10 Ulnt8 PNI Sensor Corporation DOC 1018154 r01 SeaTRAX User Manual October 2012 Page 39 0 300 1 600 2 1200 3 1800 4 2400 5 3600 6 4800 kBaudRate 14 Ulnt8 7 7200 12 8 9600 9 14400 10 19200 11 28800 12 38400 13 57600 14 115200 kMilOutput 15 Boolean True or False False kHPRDuringCal 16 Boolean True or False True kMagCoeffCopySet 18 Ulnt32 0 7 0 kAccelCoeffCopySet 19 Ulnt32 0 2 0 Refer to Figure 4 2 for additional information on mounting orientations Configuration parameters and settings for kSetConfig kDeclination Config ID 1d This sets the declination angle to determine True North heading Positive declination is easterly declination and negative is westerly declination This is not applied unless kTrueNorth is set to TRUE kTrueNorth Config ID 24 Flag to set heading out
15. SeaTRAX Connected O es N l Firmware Version s901 muss Serial Number 1031792 PCA Version ROWBIFS Connection Configuration Calibration Test Log Data Graph System Log Time Stamp Event 2012 10 15 13 16 18 Checking preference file 2012 10 15 13 16 18 Preferences file not found using defaults 2 10 15 13 16 18 Enabled audible feedback 2 10 15 13 16 18 Disabled high contrast 2012 10 15 13 16 18 Enabled auto scroll 16 Enabled 3D Model Changed computer serial portto COM1 Opened serial portCOM1 Changed computer baud rate to 38400 Opened serial port COM1 Extracted module configuration Changed endianess to big endian Extracted module information Changed taps to 32 Changed acquisition mode to poll mode Disabled filter flushing Changed mounting to Standard Changed north reference to magnetic north Disabled stability checking Enabled automatic sampling Changed output to be in Degrees 2012 10 15 13 16 43 Changed HPR during Calibration The System Log tab shows all communication between PNI Studio and the SeaTRAX module since launching PNI Studio Closing PNI Studio will erase the system log Select the lt Export gt button at the bottom right of the screen to save the system log to a text file PNI Sensor Corporation DOC 1018154 r01 SeaTRAX User Manual October 2012 Page 33 7 Operation with PNI Binary Protocol The SeaTRAX utilizes a binary protocol that is transmitted over
16. Sleep Mode recovery lt 80 ms Footnotes 1 The maximum sample rate is dependent on the strength of the magnetic field 2 FIR taps set to 0 Table 3 3 Electrical Requirements Parameter Value Supply Voltage 3 8 to 9 VDC High Level Input 2 4 V minimum Low Level Input 0 6 V maximum om unica iaiia Output Voltage Swing 15 2 V typ 5 0 V min Tx Output Resistance 300 Q max sample rate 25 mA typical EEN 8 Hz TIE rate 17 mA TE During application of 180 mA pk 60 mA avg Beak Corrent Dri external power over 10 ms During logical power 135 mA pk 60 mA avg up down or Sync Trigger over 4 ms Sleep Mode Current Draw 0 3 mA typical Table 3 4 Environmental Requirements Parameter Value Operating Temperature 40C to 85C Storage Temperature 40C to 85C Footnote 1 To meet performance specifications across this range recalibration will be necessary as the temperature varies SeaTRAX User Manual r01 Page 4 Table 3 5 Mechanical Characteristics Parameter Value Dimensions w o shield 70x 11 8 x 9 8 mm U X wx h with shield 70 x 11 8 x 10 3 mm Weight 4 3 gm Connector 4 pin Molex pn 53780 0470 3 2 Mechanical Drawings DIMENSIONS IN MM and NOMINAL UNLESS OTHERWISE NOTED 70 0 Ges s alo y ne ae W O SHIELD Esa 4X R1 11 Molex PN 53780 0470 Mates with PN 51146 0400 Through hole Solder Pads for Direct Wire Conne
17. advance notice of the possibility of any such damages including but not limited to loss of use revenue or profit In no event shall PNI s total liability for all claims regarding a Product exceed the price paid for the Product PNI neither assumes nor authorizes any person to assume for it any other liabilities Some states and provinces do not allow limitations on how long an implied warranty lasts or the exclusion or limitation of incidental or consequential damages so the above limitations or exclusions may not apply to you This warranty gives you specific legal rights and you may have other rights that vary by state or province PNI Sensor Corporation DOC 1018154 r01 SeaTRAX User Manual October 2012 Page 1 2 Introduction Thank you for purchasing PNI Sensor Corporation s SeaTRAX 3 axis tilt compensated heading sensor pn 13457 with Sen Z shield or pn 13118 without Sen Z shield SeaTRAX is a high performance low power consumption tilt compensated heading sensor incorporating PNI s advanced magnetic distortion compensation and calibration scoring algorithms to provide industry leading heading accuracy SeaTRAX combines PNI s patented magneto inductive sensors and measurement circuit technology with a 3 axis MEMS accelerometer for unparalleled cost effectiveness and performance SeaTRAX was designed with oceanology markets in mind Specifically the narrow form factor makes it ideal for inclusion in streamers and towed array
18. button reverts PNI Studio program to the factory default settings 6 3 11 Retrieve Clicking on this button causes PNI Studio to read the settings from the module and display them on the screen PNI Sensor Corporation DOC 1018154 r01 SeaTRAX User Manual October 2012 Page 25 6 4 Calibration Tab PNV er 610 File Edit Module SeaTRAX Connected O AE N l Firmware Version s901 Serial Number 1031792 PCA Version R01IMIF9 cronos Connection Configuration Calibration Test Log Data Graph System Log Samples Calibration Results e Dist Error Tilt Error Tilt Range Accel CalScore Take Sample Current Configuration Options Limited Tilt Cal Z Audible Feedback Automatic Sampling Hard Iron Only Cal lumber of samples is 12 Accel Only Cal 2D Only Cal Heading Pitch Roll S Accel Cal with Mag Full Range Cal 000 0 000 0 000 0 Clear Accel Cal to Factory _ClearMaqCaltoFactory Save Note The default settings are recommended for the highest accuracy and quality of calibration 6 41 Samples Before proceeding refer to Section 5 for the recommended calibration procedure corresponding to the calibration method selected on the Configuration tab Clicking the lt Start gt button begins the calibration process and immediately takes the first sample If Automatic Sampling is not checked on the Configuration tab it is necessary to click the lt Take Sample gt button
19. edges taking one calibration sample on each edge Then place the SeaTRAX flat on the surface and take a calibration sample then flip it over roll it 180 and take another sample Next starting with the SeaTRAX as shown on the right take a calibration point with it being vertical 0 Now tilt the SeaTRAX back 45 and take another calibration point 45 then tilt the device forward 45 and take another calibration point 45 Repeat this 3 point calibration process for the SeaTRAX with it resting on each of its 4 corners Note that it is possible to perform an Accelerometer Calibration with as few as 12 sample points although it generally is more difficult to obtain a good calibration with just 12 sample points Also the maximum number of calibration points is 18 PNI Sensor Corporation DOC 1018154 r01 SeaTRAX User Manual October 2012 Page 17 Figure 5 2 Accelerometer Calibration Starting Orientations 5 2 2 Mag and Accel Calibration The SeaTRAX allows for a simultaneous magnetometer and accelerometer calibration This requires a good calibration pattern stable measurements not handheld and installation in the user s system such that the appropriate local magnetic environment is present PNI recommends 18 to 32 calibration points for a Mag and Accel Calibration although 12 points is acceptable but less likely to yield good results The Accelerometer Only Calibration pattern discussed in Section 5 2 wil
20. field and local magnetic sources The SeaTRAX can compensate for local static magnetic sources However a magnetic source which PNI Sensor Corporation DOC 1018154 r01 SeaTRAX User Manual October 2012 Page 11 19 not static such as a motor which turns on off can create errors and it is not possible to compensate for such a dynamic nature In such cases keeping the SeaTRAX away from dynamic magnetic fields is recommended or taking measurements only when the state of the magnetic field is known For example only take measurements when a nearby motor is turned off The main objective of a magnetic user calibration is to compensate for hard iron and soft iron distortions to the magnetic field caused by components within the user s host system To that end the SeaTRAX needs to be mounted within the host system and the entire host system needs to be moved as a single unit during a user calibration The SeaTRAX allows the user to perform a calibration only in a 2D plane or with limited tilt but provides the greatest accuracy if the user can rotate through a full sphere The following subsections provide instructions for performing a magnetic calibration of a SeaTRAX system Calibration may be performed using Studio or using the PNI binary protocol and up to 8 sets of calibration coefficients may be saved The recommended calibration patterns described in the following sub sections provide a good distribution of sample points Also PNI recomm
21. i Called by the ConmProtocol obj ect when a frame is completely recei ved voi d SeaTRAX Handl eCom Ul nt 8 frameType void dataPtr Ulnt16 dat aLen Ulnt8 data Unt8 dataPtr swi t ch f r ame Type case ConmPr ot ocol kGet Dat aResp Parse the data response Ul nt8 count dat al 0 The nunber of data elements returned Ul nt32 pntr 1 Used to retrieve the returned el erents The data elements we request ed Fl oat 32 heading pitch roll temperature if count kDat aCount Message is a function that displays a C formatted string simlar to printf Wessage Recei ved data el ement s inst ead of the requested r n Ul nt 16 count Ul nt 16 kDat aCount return SeaTRAX User Manual r01 Page 66 loop through and collect the elements whi e count The elements are received as type ie kHeadi ng data swi t ch dat al pnt r read the type and go to the first byte of the data Onl y handling the 4 elements we are ooking for case ConmPr ot ocol kHeadi ng Move sour ce destination size bytes Move copies the specified number of bytes fromthe source pointer to the destination pointer Store the headi ng Move Ai dat al pntr amp headi ng TT TT si zeof headi ng increase the pointer to point to the next data element type pntr si zeof headi ng br eak case CommPr ot ocol kPitch
22. i ndex 0 our location in the frame we are putting together Ul nt 16 crc the CRC to add to the end of the packet Ul nt 16 count the total length the packet wll be count Unt16 len kPacket M nS ze exit wthout sending if there is too much data to fit inside our packet if len gt kBufferSi ze kPacketMnSi ze return Store the total len of the packet including the len bytes 2 the frame ID 1 the data len and the crc 2 If no data is sent the mn len s 5 PNI Sensor Corporation DOC 1018154 r01 SeaTRAX User Manual October 2012 Page 61 mOut Dat al i ndex OUL Dat al i ndex count gt gt 8 count amp OxFF store the frame ID mOut Dat a i ndex frameType copy the data to be sent while len mQui Dat a i ndex dat a compute and add the crc crc CRO OUL Data index mQut Dat a i ndex crc gt gt 8 OUL Dat al i ndex crc amp OXFF Wite block wll copy and send the data out the serial port ner i al Port gt W i t eB ock mQut Dat a index Ef Call the functions in serial port necessary to change the baud rate voi d ConmPr ot ocol Set Baud Ul nt 32 baud mer al Port gt Set BaudRat ei baud n6er i al Port gt l nQ ear clear any data that was already waiting in the buffer Update the CRC for transmtted and received data using the CQ TT 16bit algorithm X 16 X12 X5 1
23. the new baud rate for the module e Click the lt Power Down gt button The button will change to read lt Power Up gt e Inthe Computer window select same baud rate for the computer e Click the lt Power Up gt button The button will revert back to lt Power Down gt Note While the SeaTRAX can operate at a baud rate of 230400 a PC serial port normally will not operate this fast SeaTRAX User Manual r01 Page 20 6 2 3 Changing Modules Once a connection has been made PNI Studio will recall the last settings If a different module is used click the lt Connect gt button once the new module is attached This will reestablish a connection assuming the module baud rate is unchanged 6 3 Configuration Tab PNV er 5 U Module SeaTRAX Connected Firmware Version s901 E 5 Serial Number 1031792 Power Down own PCA Version R01IMIF9 Connection Configuration Calibration Test Log Data Graph System Log Mounting Options Filter Settings Calibration Settings Standard Taps 32 E Z Automatic Sampling North Reference Acquisition Settings Calibration Points 1 2 Full Range Calibration OHI Only Calibration Deciinetion BS se U O Limited Tilt Range Calibration Acquire Delay 0 000 2D Calibration O Accel only Calibration O Accel Calibration with Mag O Magnetic True Mode Poll Continuous Endianess O Big O Little Sample Delay 0000
24. when the calibration sample point are taken then this flag should be set to FALSE kBaudRate Config ID 14 Baud rate index value A power down power up cycle is required when changing the baud rate kMilOutput Config ID 154 This flag sets the heading pitch and roll output to mils By default kMilOutput is set to FALSE and the heading pitch and roll output are in degrees Note that 360 degrees 6400 mils such that 1 degree 17 778 mils or 1 mil 0 05625 degree kHPRDuringCal Config ID 164 This flag sets whether or not heading pitch and roll data are output simultaneously while the SeaTRAX is being calibrated The default is TRUE such that heading pitch and roll are output during calibration FALSE disables simultaneous output kMagCoeffCopySet Config ID 184 This command provides the flexibility to store up to eight 8 sets of magnetometer calibration coefficients in the module The default is set number 0 To store a set of coefficients first establish the set number number 0 to 7 using kMagCoeffCopySet then perform the magnetometer calibration The coefficient values will be stored in the defined set number This feature is useful if the PNI Sensor Corporation DOC 1018154 r01 SeaTRAX User Manual October 2012 Page 41 heading sensor will be placed in multiple locations that have different local magnetic field properties kAccelCoeffCopySet Config ID 194 This command provides the flexibility to store up
25. would be used together for proper communication with a Sea TRAX module Note The following files are not included in the sample codes and need to be created by the user Processes h amp TickGenerator h The comments in the code explain what is needed to be sent or received from these functions so the user can write this section for the user s platform For example with the TickGenerator h the user needs to write a routing that generates 10 msec ticks 7 7 1 Header File amp CRC 16 Function type declarati ons typedef struct Ul nt8 Acqui siti onMbde FlushFilter Fl oat 32 Sensor AcqTi me Sampl eDel ay _ attribute _ packed AcqPar ans oe struct Fl oat 32 MagCal Score Fl oat 32 reservel Fl oat 32 Accel Cal Score Fl oat 32 Dist Error Fl oat 32 TiltError Fl oat 32 Tilt Range _ attribute __ packed MagCal Score enum Frame Ds Commands kGet Mdl nfo 1 kGet Modl nf oResp kSet Dat aConponent s kGet Dat a kGet Dat aResp kSet Conf i g kGet Conf i g kGet Conf i gResp kSave kSt art Cal kSt opCal kSet Filters kGet Filters kGet Fil t er sResp kPower Down kSaveDone kUser Cal SampCount kMagCal Score kSet Conf i gDone kSet Fi t er sDone kSt art Cont i nuous Mbde kt opCont i nuous Mde kPower Up kSet AcqPar ans kGet AcqPar ans kAcqPar ans Done lt SS k k k k k k LO OO zl O GO P GO M sch araa D as D D D D D D D D D D D D
26. 73620e 1 07 1024151197772e 2 08 3414139286254e 3 6 01 6637325898141e 1 09 5354386848804e 2 01 2456836057785e 2 7 06 4500864832660e 2 01 1484431942626e 1 01 7646051430536e 2 8 01 9875512449729e 2 01 2567124916369e 1 02 3794805168613e 2 9 01 2567124916369e 1 03 0686505921968e 2 10 01 1484431942626e 1 03 8014333463472e 2 11 09 5354386848804e 2 04 5402682509802e 2 12 07 1024151197772e 2 05 2436112653103e 2 13 04 6451949792704e 2 05 8693165018301e 2 DOC 1018154 r01 Page 43 PNI Sensor Corporation SeaTRAX User Manual October 2012 14 02 5971390034516e 2 06 3781858267530e 2 15 01 2710056429342e 2 06 7373451424187e 2 16 07 9724971069144e 3 06 9231 186101853e 2 17 06 9231186101853e 2 18 06 7373451424187e 2 19 06 3781858267530e 2 20 05 8693165018301e 2 21 05 2436112653103e 2 22 04 5402682509802e 2 23 03 8014333463472e 2 24 03 0686505921968e 2 25 02 3794805168613e 2 26 01 7646051430536e 2 27 01 2456836057785e 2 28 08 3414139286254e 3 29 05 3097803863757e 3 30 03 2757326624196e 3 31 02 0737124095482e 3 32 kSetFIRFiltersDone frame ID 20 01 4823725958818e 3 This frame is the response to kSetFIRFilters The frame has no payload kGetFIRFilters frame ID 134 This frame queries the FIR filter settings for the sensors Byte 1 sho
27. C Flush Filters Output HPR During Calibration Degrees OMils EEN Oof Enable 3D Model Display Note No settings will be changed in the module until the lt SAVE gt button has been selected 6 3 1 Mounting Options PNI Studio supports 16 mounting orientations as illustrated previously in Figure 4 2 The descriptions in PNI Studio are slightly different from those shown in Figure 4 2 and the relationship between the two sets of descriptions is given below PNI Sensor Corporation DOC 1018154 r01 SeaTRAX User Manual October 2012 Page 21 Table 6 1 Mounting Orientations PNI Studio Figure 4 2 PNI Studio Figure 4 2 Description Description Description Description Standard STD 0 Y Sensor Up Y Up 0 Standard 90 Y Sensor Up Plus gt Degrees US 90 Degrees epee Standard 180 S Y Sensor Up Plus a o Degrees SETE 180 Degrees TEH Standard 270 S Y Sensor Up Plus a 7 Degrees O 270 Degrees Ed X Sensor Up X Up 0 Z Sensor Down Z Down 0 X Sensor Up Plus uy S Z Sensor Down SC 2 90 Degrees AO Plus 90 Degrees DAA X Sensor Up Plus y Z Sensor Down vas e 180 Degrees E Plus 180 Degrees EE X Sensor Up Plus uy S Z Sensor Up Plus gt S 270 Degrees EE 270 Degrees SE 6 3 2 North Reference Declination also called magnetic variation is the difference between true and magnetic north It is measured in degrees east or
28. Continuous Mode 49 kSyncRead Queries the module for data in Sync Mode 15 kPowerDown Powers down the module 28 kPowerDownDone Response to kPowerDown Confirms the SeaTRAX has received a signal to 23 kPowerUpDone power up 7 4 Set Up Commands 7 4 1 Module Information kGetModinfo frame ID 14 This frame queries the device s type and firmware revision number The frame has no payload kGetModinfoResp frame ID 24 The response to kGetModInfo is given below The payload contains the device type identifier followed by the firmware revision number Payload Ulnt32 Note the model type and firmware revision can be decoded using the ASCII standard For example the hex string 00 OD 02 54 43 54 41 73 39 30 31 C7 87 can be decoded to read TCTA s901 where TCTA indicates the device is the SeaTRAX Ulnt32 and s901 indicates the firmware revision SeaTRAX User Manual r01 Page 38 7 4 2 Module Configuration kSetConfig frame ID 64 This frame sets internal configurations in the SeaTRAX The first byte of the payload is the configuration ID followed by a format specific value These configurations can only be set one at time To save these in non volatile memory the kSave command must be issued Payload Ulnt8 ID Specific Example To configure the declination the payload would look like Payload Declination ID Declination Angle Float32 Table 7 3 Configuration Identifiers Settings Config
29. Flushing the FIR filter clears all the filter values so it is necessary to fully repopulate the filter before a good reading can be given For example if 32 FIR taps is set then 32 new samples must be taken to provide a good reading It is particularly prudent to flush the filter if the Sample Delay is set to a non zero value as this will purge old data Note that flushing the filters increases the delay until data is output with the length of the delay being directly correlated to the number of FIR taps The default is not to Flush Filters 6 3 8 HPR During Calibration When the lt On gt button is selected heading pitch and roll will be output on the Calibration tab during a calibration 6 3 9 Calibration Settings Automatic Sampling When selected the module will take a sample point once minimum change and stability requirements have been satisfied If the user wants to have more control over when the point will be taken then Auto Sampling should be deselected Once deselected the lt Take Sample gt button on the Calibration tab will be active Selecting SeaTRAX User Manual r01 Page 24 the lt Take Sample gt button will indicate to the module to take a sample once the minimum requirements are met Calibration Points The user can select the number of points to take during a calibration The minimum number of points needed for an initial calibration is 10 although a hard iron only re calibration can be performed with only 4 s
30. TRAX User Manual October 2012 Page 7 4 3 Mechanical Mounting For the SeaTRAX the full radius cut outs along the long sides are intended for test fixturing and not as the mechanical mount in the user s system PNI recommends securing the long edge of the PCB to a shelf or lip in the user s system using an adhesive Ideally the SeaTRAX also would be fully potted in the user s system to reduce or eliminate shock and vibration effects Refer to Section 3 2 for dimensions hole locations and the reference frame orientation 4 3 1 Pitch and Roll Conventions The SeaTRAX uses MEMS accelerometers to measure the tilt angle of the heading sensor This data is output as pitch and roll data and is also used in conjunction with the magnetometers to provide a tilt compensated heading reading The SeaTRAX utilizes Euler angles as the method for determining accurate orientation This method is the same used in aircraft orientation where the outputs are heading also called yaw or azimuth pitch and roll When using Euler angles roll is defined as the angle rotated around an axis through the center of the fuselage while pitch is rotation around an axis through the center of the wings These two rotations are independent of each other since the rotation axes rotate with the plane body As shown in Figure 4 1 for the SeaTRAX a positive pitch is when the front edge of the board is rotated upward and a positive roll is when the right edge of the board i
31. User Manual SeaTRAX High Accuracy Heading Sensor Pon SENSOR CORPORATION Table of Contents 1 COPYRIGHT 8 WARRANTY INFORMATION cccccssssceccessssececcsssecsecesssees 1 2 INTRODUCTION score reer oini sess ursi neso sri oit swE vs 2 3 SPECIFICATIONS ccoo is a A dnu Ea russie sou N ENSE 3 3 1 Characteristics amp Requirements sese eee ee eee ee eee eee 3 3 2 Mechanical Drawing s eee eee eee ee eee 5 L SETUP iia A A A A AA 6 4 1 Electrical Connect 6 4 2 Installation LOCA Ossand n 6 4 2 1 Operate within the SeaTRAX s dynamic range see eee eee eee 7 4 2 2 Locate away from changing magnetic fields cccccsseceeeees 7 4 2 3 Mount in a physically stable location ee ee ee eee eee eee 7 4 2 4 Location verification testing sse 7 4 3 Mechanical Mounting secsi Ea E 8 4 3 1 Pitch and Roll Conventions siii eee eee eee eee 8 4 3 2 Mounting Orientation 9 5 USER CALIBRATION iii is 10 5 1 Magnetic Calibration ic ease ees eege 11 5 1 1 Full Range Calibration e ee eee eee eee eee 13 5 1 2 DCalbrati n nori 14 5 1 3 Limited Tilt Range Calbration 15 5 1 4 Hard Iron Only Calibration eceescecesessseeeesssneeeeesseeeeeeeeeaaes 16 5 2 Accelerometer Calibration sese ee eee eee e eee 16 5 2 1 Accelerometer Only Calibration ccccccccccccessssssseeeeeeeseeeeees 17 5 2 2 Mag and Accel Calibration sese eee eee 18 6 OPERATION WITH PNI STUDIO s ssssss sese ss e sss seene ennenen nenen 19 6 1 S
32. X The payload should contain the following Payload AcquisitionMode FlushFilter SensorAcqTime SampleDelay Ulnt8 Ulnt8 Float32 Float32 AcquisitionMode This flag sets whether output will be presented in Continuous or Polled Acquisition Mode Polled Mode is TRUE and is the default Polled Mode should be selected when the host system will poll the SeaTRAX for each data set Continuous Mode should be selected if the user will have the SeaTRAX output data to the host system at a relatively fixed rate FlushFilter Setting this flag to TRUE results in the FIR filter being flushed cleared after every measurement The default is FALSE Flushing the filter clears all tap values thus purging old data This can be useful if a significant change in heading has occurred since the last reading as the old heading data would be in the filter Once the taps are cleared it is necessary to fully repopulate the filter before data is output For example if 32 FIR taps is set 32 new samples must be taken before a reading will be output The length of the delay before outputting data is directly correlated to the number of FIR taps SensorAcqTime The SensorAcqTime sets the time between samples taken by the module in seconds The default is 0 0 seconds which means that the module will reacquire data immediately after the last acquisition This is an internal setting that is NOT tied to the time with which the module transmits data to the host system G
33. ame has no payload This is the ONLY command that causes the device to save information to non volatile memory kSaveDone frame ID 16 a This frame is the response to kSave frame The payload contains a UInt16 error code U indicates no error 1 indicates an error when attempting to save data to memory Payload Ulnt16 7 5 Calibration Commands 7 5 1 User Calibration Commands Before proceeding with this section please ensure you are familiar with Section 5 kStartCal frame ID 10d This frame commands the module to start a user field calibration After sending this command the module initially reports a sample count of 0 Once a PNI established stability condition is met the module takes the first calibration point and responds with kUserCalSampCount kUserCalSampCount will continue to be sent after each sample is taken If auto sampling subsequent samples will be taken when the minimum change and stability conditions are met If manually sampling samples will be taken after the kTakeUserCalSample command is sent and the stability condition is met See Section 3 for more information on the various calibration procedures SeaTRAX User Manual r01 Page 46 Note The payload needs to be 32 bit 4 byte If no payload is entered or if less than 4 bytes are entered the unit will default to the previous calibration method a Payload gt Cal Option t Ulnt32 gt The CalOption values are gi
34. amples The module will need to be rotated through at least 180 degrees in the horizontal plane with a minimum of at least 1 positive and 1 negative Pitch and at least 1 positive and 1 negative Roll as part of the 12 points Calibration Method Buttons Full Range Calibration recommended calibration method when gt 45 of tilt is possible The minimum recommended number of calibration points is 12 Hard Iron Only Calibration serves as a hard iron recalibration to a prior calibration If the hard iron distortion around the module has changed this calibration can bring the module back into specification The minimum recommended number of calibration points is 6 Limited Tilt Range Calibration recommended calibration method when gt 5 of tilt calibration is available but tilt is restricted to lt 45 i e full range calibration is not possible The minimum recommended number of calibration points is 12 2D Calibration recommended when the available tilt range is limited to lt 5 The minimum recommended number of calibration points is 12 Accel Calibration Only The user should select this when accelerometer calibration will be performed The minimum recommended number of calibration points is 18 Accel Calibration w Mag The user should select this when magnetometer and accelerometer calibration will be performed simultaneously The minimum recommended number of calibration points is 18 6 3 10 Default Clicking this
35. an RS232 UART The parameters should be set as follows Table 7 1 UART Configuration Parameter Value Number of Data Bits 8 Start Bits 1 Stop Bits 1 Parity none 7 1 Datagram Structure The data structure is shown below ByteCount Packet Frame CRC 16 Ulnt16 1 4092 Ulnt8 Ulnt16 dira e Payload Uints 1 4091 Ulnt8 Figure 7 1 Datagram Structure The ByteCount is the total number of bytes in the packet including the CRC 16 checksum CRC 16 is calculated starting from the ByteCount to the last byte of the Packet Frame The ByteCount and CRC 16 are always transmitted in big Endian Two examples follow Example The complete packet for the kGetModInfo command which has no payload is ByteCount Frame ID Checksum Example Below is a complete sample packet to start a 2D Calibration kStartCal 00 09 00 00 00 14 5C F9 ByteCount Frame ID CalOption CalOption Checksum 2D Calibration SeaTRAX User Manual r01 Page 34 7 2 Parameter Formats Note Floating point based parameters conform to ANSI IEEE Std 754 1985 Please refer to the Standard for more information PNI also recommends the user refer to the compiler s instructions to understand how the compiler implements floating point format 64 Bit Floating Point Float64 Below is the 64 bit float format in big Endian In little Endian the bytes are in reverse order in 4 byte groups eg big Endian ABCD EFGH little E
36. at is not fixed with respect to the module Dist Error Indicates the quality of the sample point distribution primarily looking for an even yaw distribution Significant clumping or a lack of sample points in a particular section can result in a poor score The score should be lt 1 and close to 0 Tilt Error Indicates the contribution to the Mag CalScore caused by tilt or lack thereof and takes into account the calibration method The score should be lt 1 and close to 0 Tilt Range This reports the larger of either half the full pitch range or half the full roll range of sample points For example if the module is pitched 10 to 20 and rolled 25 to 15 the Tilt Range value would be 20 as derived from 25 15 2 For Full Range Calibration and Hard Iron Only Calibration this should be gt 45 For 2D Calibration this ideally should be 2 For Limited Tilt Range Calibration the value should be as large a possible given the user s constraints Accel CalScore Represents the over riding indicator of the quality of the accelerometer calibration Acceptable scores will be lt 1 If either CalScore is too high click the lt Start gt button to begin a new calibration If the calibration is acceptable then click the lt Save gt button in the Calibration Results window to save the calibration to the module s flash If this button is not selected then the module will need to be recalibrated after a p
37. c Ulnt8 ID Specific Example If heading and pitch are set to be output per the kSetDataComponents command the payload would look like Payload ID Count Heading ID Heading Pitch ID Pitch Output Float32 Float32 7 6 4 Sleep Mode For certain applications low power consumption is critical Consequently the Sea TR A X may be powered down and put into Sleep Mode when heading data is not required kPowerDown frame ID 154 This frame is used to power down the module which puts the module in Sleep Mode The frame has no payload The command will power down all peripherals including the sensors microprocessor and RS 232 driver However the driver chip has a feature to keep the Rx line enabled The SeaTRAX will power up when it receives any signal on the native UART Rx line kPowerDownDone frame ID 284 This frame confirms the SeaTRAX received a command to power down The frame has no payload kPowerUpDone frame ID 234 This frame confirms the SeaTRAX received a command to power up The SeaTRAX will power up when it receives any signal on the native UART Rx line The frame has no payload Since the module was previously powered down which drives the RS 232 driver TX line low break signal it is recommended to disregard the first byte PNI Sensor Corporation DOC 1018154 r01 SeaTRAX User Manual October 2012 Page 55 7 7 Code Examples The following example files CommProtocol h CommProtocol cp SeaTRAX h and SeaTRAX cp
38. ce is pitched 10 to 20 and rolled 25 to 15 the TiltRange value would be 20 as derived from 25 15 2 For Full Range Calibration and Hard Iron Only Calibration this should be gt 45 For 2D Calibration ideally this should be 2 For Limited Tilt Range Calibration the value should be as large a possible given the user s constraints 7 5 4 Reset to Factory Calibration kSetFactoryMagCoeff frame ID 29 This frame clears the magnetometer calibration coefficients and loads the original factory generated coefficients The frame has no payload This frame must be followed by the kSave frame to save the change in non volatile memory kSetFactoryMagCoeffDone frame ID 30 This frame is the response to kFactoryMagCoeff frame The frame has no payload kSetFactoryAccelCoeff frame ID 36 This frame clears the accelerometer calibration coefficients and loads the original factory generated coefficients The frame has no payload This frame must be followed by the kSave frame to save the change in non volatile memory kSetFactoryAccelCoeffDone frame ID 37 This frame is the response to kFactoryAccelCoeff frame The frame has no payload SeaTRAX User Manual r01 Page 50 7 6 Operation Commands 7 6 1 Data Acquisition Parameters How data will be measured is established with the Data Acquisition Parameters kSetAcqParams frame ID 24 This frame sets the sensor acquisition parameters in the SeaTRA
39. cteristics amp Requirements Table 3 1 Performance Characteristics Parameter Value lt 65 of pitch after full range calibration lt 0 3 rms lt 80 of pitch after full range calibration lt 0 5 rms Accuracy lt 5 of pitch after 2D calibration lt 2 0 rms dd using imited tit calibration 1 20 ms Resolution 0 1 Repeatability 0 05 rms Barge Pitch 90 Roll 180 Pitch 0 2 rms Attitude Accuracy SE E Roll lt 80 of pitch 0 42 rms lt 86 of pitch 1 0 rms Resolution 0 01 Repeatability 0 05 rms Maximum Operational Dip Angle 85 Calibrated Field Range 1258 uT Magnetometers Resolution 0 05 uT Repeatability 0 1 UT Footnotes 1 Specifications are subject to change Assumes the SeaTRAX is motionless and the local magnetic field is clean relative to the user calibration 2 For example if the calibration was performed over 10 of tilt then the SeaTRAX would provide lt 2 rms accuracy over 20 of tilt 3 Performance at maximum operational dip angle will be somewhat degraded PNI Sensor Corporation DOC 1018154 r01 SeaTRAX User Manual October 2012 Page 3 Table 3 2 I O Characteristics Parameter Value Communication Interface RS232 UART Communication Protocol PNI Binary Communication Rate 300 to 115200 baud Maximum Sample Rate 50 samples sec Time to Initial Initial power up lt 210 ms Good Data
40. ction 4 places 0 94 mm ID holes 20 AWB max pls A WITH SHIELD 2 3 The SeaTRAX with the shield is PNI pn 13457 while without the shield the it is pn 13118 The default orientation is for the arrowhead to point in the forward direction Note The full radius cut outs along the long sides are intended for test fixturing and not as the mechanical mount in the user s system PNI recommends using an adhesive to secure the long edge of the PCB to a shelf or lip in the user s system Typically SeaTRAX would be potted in the user s system Figure 3 1 SeaTRAX Mechanical Drawing PNI Sensor Corporation DOC 1018154 r01 SeaTRAX User Manual October 2012 Page 5 4 Set Up This section describes how to configure the SeaTRAX in your host system To install the SeaTRAX into your system follow these steps e Make electrical connections to the SeaTRAX e Evaluate the SeaTRAX using PNI Studio or a binary terminal emulation program such as RealTerm or Tera Term to ensure the heading sensor generally works correctly e Choose a mounting location e Mechanically mount the SeaTRAX in the host system e Perform a field calibration 4 1 Electrical Connections The SeaTRAX incorporates a 4 pin Molex connector part number 53780 0470 which mates with Molex part 51146 0400 or equivalent and alternatively allows the user to directly solder to the board using the 4 through holes directly in front of the connector The pin out is given
41. e device is expected to encounter in use Top Views Side Views Minimum 12 good user re calibration points Additional points can be added including upside down if possible Large Positive Pitch a 5 Alternate Roll between gt er points odd number DNA points positive roll Nun even negative roll Large Negative n Pitch Note While Figure 5 1 shows the location of the device changing this is for illustration purposes and it is best for the location of the device to remain constant while only the orientation is changed PNI Sensor Corporation DOC 1018154 r01 SeaTRAX User Manual October 2012 Page 13 Table 5 2 12 Point Full Range Calibration Pattern Sample Yaw Pitch Roll First Circle 1 0 5 30 to 40 2 90 5 30 to 40 3 180 o 30 to 40 4 270 5 30 to 40 Second Circle 5 30 gt 45 30 to 40 6 120 gt 45 30 to 40 7 210 gt 45 30 to 40 8 300 gt 45 30 to 40 Third Circle 9 60 lt 45 30 to 40 10 150 lt 45 30 to 40 11 240 lt 45 30 to 40 12 330 lt 45 30 to 40 Footnote 1 Yaw listings are not absolute heading directions but rather relative heading referenced to the first sample 5 1 2 2D Calibration A 2D Calibration is intended for very low tilt operation lt 5 where calibrating the SeaTRAX w
42. ends the location of the SeaTRAX remain fairly constant while only the orientation is changed Table 5 1 Magnetic Calibration Mode Summary ofSamplesin Allowable ee Static Accuracy de Recommended Range of g Cal Pattern of Samples Full Range 0 3 rms gt 45 12 10 32 2D Calibration lt 2 lt 15 12 10 32 Limited Tilt lt 2 over 2x tilt A S 10 32 Range alas 5 to 45 12 Hard Iron Only Restores prior 43 6 eos accuracy Before proceeding with a calibration ensure the SeaTRAX is properly installed in the host system The device should be installed as discussed in Section 4 and the software should be properly configured with respect to the mounting orientation Endianness north reference etc Section 6 4 outlines how to perform a calibration using Studio while Section 7 5 2 provides a step by step example of how to perform a calibration using the PNI protocol SeaTRAX User Manual r01 Page 12 5 1 1 Full Range Calibration A Full Range Calibration is appropriate when the SeaTRAX can be tilted 45 or more This method compensates for hard and soft iron effects in three dimensions and allows for the highest accuracy readings The recommended 12 point calibration pattern is a series of 3 circles of evenly spaced points as illustrated in Figure 5 1 and listed in Table 5 2 The pitch used in the second and third circles of the calibration should at least match the maximum and minimum pitch th
43. enerally speaking the SensorAcqTime is either set to 0 in which case the SeaTRAX is constantly sampling or set to equal the SampleDelay value The advantage of running with an SensorAcqTime of 0 is the FIR filter can run with a relatively high FIR Tap value to provide stable and timely data The advantage of PNI Sensor Corporation DOC 1018154 r01 SeaTRAX User Manual October 2012 Page 51 using a greater SensorAcqTime is power consumption can be reduced assuming the SampleDelay is no less than the SensorAcqTime SampleDelay The SampleDelay is relevant when the Continuous Acquisition Mode is selected It is the time delay in seconds between completion of the SeaTRAX sending one set of data and the start of sending the next data set The default is O seconds which means the SeaTRAX will send new data as soon as the previous data set has been sent Note that the inverse of the SampleDelay is somewhat greater than the actual sample rate since the SampleDelay does not include actual acquisition time kSetAcqParamsDone frame ID 26 This frame is the response to kSetAcqParams frame The frame has no payload kGetAcqParams frame ID 25 4 This frame queries the unit for the acquisition parameters The frame has no payload kGetAcqParamsResp frame ID 27 This frame is the response to kGetAcqParams frame The payload has the same structure as kSetAcqParams 7 6 2 Data Components What data will be measured is established with t
44. fields It is not possible to calibrate for changing magnetic anomalies Thus for greatest accuracy keep the SeaTRAX away from sources of local magnetic distortion that will change with time such as electrical equipment that will be turned on and off or ferrous bodies that will move Make sure the SeaTRAX is not mounted close to cargo or payload areas that may be loaded with large sources of local magnetic fields 4 2 3 Mount in a physically stable location Choose a location that is isolated from excessive shock oscillation and vibration The SeaTRAX works best when stationary Any non gravitational acceleration results in a distorted reading of Earth s gravitational vector which affects the heading measurement 4 2 4 Location verification testing Location verification testing should be performed at an early stage of development to understand and accommodate the magnetic distortion contributors in a host system Determine the distance range of field distortion Place the heading sensor in a fixed position then move or energize suspect components while observing the output to determine when they are an influence Determine if the magnetic field is within the dynamic range of the heading sensor With the heading sensor mounted rotate and tilt the system in as many positions as possible While doing so monitor the magnetometer outputs observing if the maximum linear range is exceeded PNI Sensor Corporation DOC 1018154 r01 Sea
45. ge is 0 0 to 359 9 the pitch range is 90 0 to 90 0 and the roll range is to 180 0 to 180 0 kTemperature Component ID 7 This value is provided by the device s internal temperature sensor Its value is in degrees Celsius and has an accuracy of 3 C kDistortion Component ID 8 This flag indicates at least one magnetometer axis reading is beyond 125 uT kCalStatus Component ID 9 This flag indicates the user calibration status False means it is not user calibrated and this is the default value PNI Sensor Corporation DOC 1018154 r01 SeaTRAX User Manual October 2012 Page 53 kAccelX kAccelY 8 kAccelZ Component IDs 214 224 234 These values represent the accelerometer sensor data for the x y and z axis respectively The values are normalized to g Earth s gravitational force kMagX kMagY amp kMagZ Component IDs 274 284 294 These values represent the magnetic sensor data for the x y and z axis respectively The values are given in uT 7 6 3 Making a Measurement kGetData frame ID 44 If the SeaTRAX is configured to operate in Poll Acquisition Mode as defined by kSetAcqParams then this frame requests a single measurement data set The frame has no payload The response is kGetDataResp kStartContinuousMode frame ID 21 If the SeaTRAX is configured to operate in Continuous Acquisition Mode as defined by kSetAcqParams then this frame initiates the outputting of data at a re
46. he Data Components kSetDataComponents frame ID 34 This frame defines what data is output when kGetData is sent Table 7 6 summarizes the various data components and more detail follows this table Note that this is not a query for the device s model type and software revision see kGetModInfo The first byte of the payload indicates the number of data components followed by the data component IDs Note that the sequence of the data components defined by kSetDataComponents will match the output sequence of kGetDataResp Payload pos er ve es Jo Ulnt8 Ulnt8 Ulnt8 Ulnt8 Example To query for heading and pitch the payload should contain SeaTRAX User Manual r01 Page 52 Payload ID Count Heading ID Pitch ID When querying for data kGetData frame the sequence of the data component output follows the sequence of the data component IDs as set in this frame Table 7 6 Component Identifiers Component Component ID Format kHeading Float32 degrees kPitch 24 Float32 degrees kRoll 25 Float32 degrees kTemperature 7 Float32 Celsius kDistortion 8 Boolean Nie kCalStatus 9 Boolean Sea kAccelX 21 Float32 G kAccelY 22 Float32 G kAccelZ 23 Float32 G kMagX 27 Float32 uT kMagY 28 Float32 uT kMagZ 29 Float32 D Component types are listed below All are read only values kHeading kPitch kRoll Component IDs 54 24a 254 Provides heading pitch and roll outputs The heading ran
47. ick 10msec if Ticks gt mli me tell the module to take a sample SendConm ConmPr ot ocol kGet Data mii me Ticks 100 take a sample every second n6t ep br eak case 3 Ticks is a timer function 1 tick 10mec if Ticks gt mResponseli me Message No response fromthe module Check connection and try Ran oy t ep 0 br eak def aul t br eak PNI Sensor Corporation DOC 1018154 r01 SeaTRAX User Manual October 2012 Page 69
48. ick is 1 60 second PNI Sensor Corporation DOC 1018154 r01 SeaTRAX User Manual October 2012 Page 31 6 7 Graph Tab IPN File Edit Module SeaTRAX E N l Firmware Version s901 Serial Number 1031789 PCA Version R0113178 Connection Configuration Calibration Test Graph Data w o User Cal O with User Cal MX Filt MY Filt MX Cal MY Cal CE cee D Auto Scroll Connected o MX 20 99 17 78 14 57 11 36 8 15 Log Data Graph System Log 494 20 72 14 30 The graph provides a 2 axis X Y plot of the measured field strength If w o User Cal graph data is selected the plot and data provide magnetic field strength measurements after the FIR taps are applied but prior to applying the user calibration coefficients If with User Cal graph data is selected the plot and data provide data after applying the FIR filter and the user calibration coefficients The sample plot shows a 360 rotation in the horizontal plane with both w o User Cal and with User Cal selected The offset between these two plots represents the effect of the calibration coefficients The graph can be used to visually see hard and soft iron effects within the environment measured by the SeaTRAX as well as corrected output after a user calibration has been performed SeaTRAX User Manual r01 Page 32 6 8 System Log Tab IPN Er Eile Edit Module
49. ing old data This can be useful if a significant change in heading has occurred since the last reading as the old heading data would be in the filter Once the taps are cleared it is necessary to fully repopulate the filter before data is output For example if 32 FIR taps is set 32 new samples must be taken before a reading will be output The length of the delay before outputting data is directly correlated to the number of FIR taps kSetFIRFilters frame ID 124 The payload for kSetFIR Filters is given below Ulnt8 Ulnt8 Payload Ulnt8 ID Specific ID Specific ID Specific ID Specific Byte 1 should be set to 3 and Byte 2 should be set to 1 The third payload byte indicates the number of FIR taps to use which can be 0 no filtering 4 8 16 or 32 This is followed by the tap values 0 to 32 total Values can be in the payload with each Value being a Float64 and suggested values given in Table 7 5 Table 7 5 Recommended FIR Filter Tap Values 4 Tap Filter 8 Tap Filter 16 Tap Filter 32 Tap Filter 1 04 6708657655334e 2 01 9875512449729e 2 07 9724971069144e 3 01 4823725958818e 3 2 04 5329134234467e 1 06 4500864832660e 2 01 2710056429342e 2 02 0737124095482e 3 3 04 5329 134234467e 1 01 6637325898141e 1 02 5971390034516e 2 03 2757326624196e 3 4 04 6708657655334e 2 02 4925036373620e 1 04 6451949792704e 2 05 3097803863757e 3 5 02 49250363
50. ith greater tilt is not practical This procedure calibrates for hard and soft iron effects in only two dimensions and in general is effective for operation and calibration in the tilt range of 5 to 5 The recommended 12 point calibration pattern is a circle of evenly spaced points as given in Table 5 3 SeaTRAX User Manual r01 Page 14 Footnote Table 5 3 12 Point 2D Calibration Pattern Sample Yaw Pitch Roll 1 0 0 0 2 30 max negative max negative 3 60 0 0 4 90 max positive max positive 5 120 0 0 6 150 max negative max negative 7 180 0 0 8 210 max positive max positive 9 240 0 0 10 270 max negative max negative 11 300 0 0 12 330 max positive max positive 1 For best results the tilt experienced during calibration should match that experienced in service For example if the SeaTRAX is restrained to a level plane in service then calibration should be in a plane where max positive and max negative are 0 5 1 3 Limited Tilt Range Calibration A Limited Tilt Range Calibration is recommended when 45 of tilt isn t feasible but gt 5 of tilt is possible It provides both hard iron and soft iron distortion correction The recommended 12 point calibration pattern given below is a series of 3 circles of evenly spaced points with as much tilt variation as expected during use
51. l calibration point The payload is defined below and the various payload components are discussed after this Payload MagCalScore Bytes 5 8 AccelCalScore DistErmor TiltError TiltRange Float32 Float32 Float32 Float32 Float32 Float32 MagCalScore Represents the over riding indicator of the quality of the magnetometer calibration Good scores will be lt 1 for full range calibration lt 2 for other methods Note that it is possible to get acceptable scores for DistError and TiltError and still have a rather high MagCalScore value The most likely reason for this is the SeaTRAX is close to a source of local magnetic distortion that is not fixed with respect to the device Bytes 5 8 Reserved for PNI use AccelCalScore Represents the over riding indicator of the quality of the accelerometer calibration A good score is lt l DistError Indicates if the distribution of sample points is good with an emphasis on the heading distribution A good score is 0 Significant clumping or a lack of sample points in a particular section can result in a poor score TiltError Indicates if the SeaTRAX experienced sufficient tilt during the calibration taking into account the calibration method A good score is 0 PNI Sensor Corporation DOC 1018154 r01 SeaTRAX User Manual October 2012 Page 49 TiltRange This reports the larger of either half the full pitch range or half the full roll range of sample points For example if the devi
52. l work for a Mag and Accel Calibration Optimal performance is obtained when all rotations of the cube are performed towards magnetic north to achieve the widest possible magnetic field distribution Note that combining calibrations only makes sense if all the host system s magnetic distortions steel structures or batteries for instance are present and fixed relative to the module when calibrating If the Accelerometer Only Calibration is performed the user s system distortions are not relevant which allows the SeaTRAX to be removed from the host system in order to perform the Accelerometer Only Calibration SeaTRAX User Manual r01 Page 18 6 Operation with PNI Studio PNI Studio puts an easy to use graphical user interface GUI onto the binary command language used by the SeaTRAX PNI Studio is intended for evaluating demonstrating and calibrating the SeaTRAX module The program includes the ability to log and save the outputs from the SeaTRAX to a file for off line evaluation Check the PNI website for the latest PNI Studio updates at www pnicorp com Note PNI Studio is compatible with the TCM XB and TCM MB as well as the SeaTRAX The PNI Studio evaluation software communicates with the SeaTRAX through the RS232 serial port of a computer 6 1 Installation PNI Studio is provided as an executable program which can be downloaded from PNI s website It will work with Windows XP Windows Vista Windows 7 and Mac OS X opera
53. latively fixed data rate where the data rate is established by the SampleDelay parameter The frame has no payload The response is kGetDataResp kStopContinuousMode frame ID 22 This frame commands the SeaTRAX to stop data output when in Continuous Acquisition Mode The frame has no payload kSyncRead frame ID 49 If the SeaTRAX is configured to operate in Sync Mode as defined by kSetSyncMode then this frame wakes up the module requests a measurement outputs the results then powers down again This frame has no payload The response is kGetDataResp with heading pitch and roll automatically set as the data component IDs Prior to sending the kSyncRead frame the user s system must first send an FF string which wakes up the system then wait some minimum delay time before sending the kSyncRead frame The minimum delay time is dependent on the baud rate and for a baud rate equal to or slower than 9600 there is no delay The minimum delay is defined by the same formula given for switching from Sync Mode to Normal Mode in kSetSyncMode SeaTRAX User Manual r01 Page 54 kGetDataResp frame ID 54 The response to kGetData kStartContinuousMode and kSyncRead is kGetDataResp The specific data fields that will be output ID 1 Value ID 1 etc should have been previously established by the kSetDataComponents command frame Payload ID Count Value ID 1 Value ID 2 Value ID 3 Ulnt8 Ulnt8 ID Specific Ulnt8 ID Specifi
54. lay time is dependent on the baud rate and for a baud rate equal to or slower than 9600 there is no delay For baud rates greater than 9600 the minimum delay is equal to Minimum delay after sending FF in seconds 7E 3 10 baud rate For example with a baud rate of 38400 the minimum delay after sending FF is Minimum delay at 38400 baud 7E 4 10 38400 4 4E 4 seconds 440 us Sync Mode generally is intended for applications in which sampling does not occur frequently For applications where Sync Mode sampling will be at a frequency of 1 Hz or higher there is a minimum allowable delay between taking samples This minimum delay between samples approximately inverse to the maximum sample rate varies from 100 msec to 1 06 second and is a function of the number of FIR filter taps as defined by the following formula Minimum Delay between Samples in seconds 0 1 0 03 number of Taps PNI Sensor Corporation DOC 1018154 r01 SeaTRAX User Manual October 2012 Page 45 kSetSyncModeResps frame ID 47 This frame is the response to kSetSyncMode frame The payload contains the Mode ID requested Payload gt Mode ID lt Ulnt8 gt 7 4 5 Saving Settings kSave frame ID 94 This frame commands the SeaTRAX to save internal configurations and user calibration to non volatile memory Internal configurations and user calibration are restored on power up The fr
55. le 7 3 Configuration Identifiers 39 Table 7 4 Sample Points 41 Table 7 5 Recommended FIR Filter Tap Values 43 Table 7 6 Component Identifiers 53 List of Figures Figure 3 1 SeaTRAX Mechanical Drawing 5 Figure 4 1 Positive amp Negative Roll and Pitch Definition 8 Figure 4 2 Mounting Orientations 9 Figure 5 1 12 Point Full Range Calibration 13 Figure 5 2 Accelerometer Calibration Starting Orientations 18 Figure 7 1 Datagram Structure 34 PNI Sensor Corporation DOC 1018154 r01 SeaTRAX User Manual October 2012 Page iii 1 Copyright 8 Warranty Information O Copyright PNI Sensor Corporation 2012 All Rights Reserved Reproduction adaptation or translation without prior written permission is prohibited except as allowed under copyright laws Revised October 2012 For most recent version visit our website at www pnicorp com PNI Sensor Corporation 133 Aviation Blvd Suite 101 Santa Rosa CA 95403 USA Tel 707 566 2260 Fax 707 566 2261 Warranty and Limitation of Liability PNI Sensor Corporation PNI manufactures its SEATRAX products Products from parts and components that are new or equivalent to new in performance PNI warrants that each Product to be delivered hereunder if properly used will for one year following the date of shipment unless a different warranty time period for such Product is specified 1 in PNI s Price List in effect at time of order acceptance or ii on PNI s web site www p
56. llowed by the data component ID value pairs The sequence of the component IDs are kHeading kPitch and kRoll PNI Sensor Corporation DOC 1018154 r01 SeaTRAX User Manual October 2012 Page 47 kTakeUserCalSample frame ID 31 This frame commands the SeaTRAX to take a sample during user calibration The frame has no payload kUserCalSampleCount frame ID 17 This frame is sent from the SeaTRAX after taking a calibration sample point The payload contains the sample count with the range of 0 to 32 Payload SampleCount Ulnt32 kStopCal frame ID 114 This command aborts the calibration process Assuming the minimum number of sample points for the calibration as defined in Table 7 4 is not acquired prior to sending kStopCal the prior calibration results are retained If the acquired number of sample points prior to sending kStopCal is within the allowable range of kUserCalNumPoints then new calibration coefficients and a new score will be generated For instance if kUserCalNumPoints is set to 32 for a full range calibration and kStopCal is sent after taking the 12 sample point then a new set of coefficients will be generated based on the 12 sample points that were taken They will not be saved however unless the kSave command is sent 7 5 2 Performing a User calibration The steps below provide an example of the steps to perform a user calibration e Using the kSetConfig command set kUserCalAutoSampling Fal
57. ndian DCBA HGFE 63 62 5251 S Exponent Mantissa The value v is determined as if and only if O lt Exponent lt 2047 v 1 S 2 Exponent 1023 1 Mantissa 32 Bit Floating Point Float32 Shown below is the 32 bit float format in big Endian In little Endian format the 4 bytes are in reverse order LSB first 3130 2322 S Exponent Mantissa The value v is determined as if and only if 0 lt Exponent lt 255 v 1 S 2 Exponent 127 1 Mantissa Signed 32 Bit Integer Sint32 SInt32 based parameters are signed 32 bit numbers 2 s compliment Bit 31 represents the sign of the value O positive 1 negative 31 24 23 1615 87 0 msb Isb Big Endian 7 015 8 23 1631 24 Isb msb Little Endian PNI Sensor Corporation DOC 1018154 r01 SeaTRAX User Manual October 2012 Page 35 Signed 16 Bit Integer Sint16 SIntl6 based parameters are signed 16 bit numbers 2 s compliment Bit 15 represents the sign of the value O positive 1 negative 15 87 0 7 0 15 8 msb Isb Isb msb Big Endian Little Endian Signed 8 Bit Integer SInt8 UInt8 based parameters are unsigned 8 bit numbers Bit 7 represents the sign of the value O positive 1 negative 7 0 byte Unsigned 32 Bit Integer Ulnt32 Ulnt32 based parameters are unsigned 32 bit numbers
58. nents of the user s system can be compensated for o Allows for 4 different methods of calibration Full Range Calibration provides the highest heading accuracy but requires 245 of pitch 2D and Limited Tilt Calibration allow for good calibration when the range of allowable motion is limited Hard Iron Only Calibration updates the hard iron compensation coefficients with a relatively easy procedure e Accelerometer calibration requires rotating the SeaTRAX through a full sphere of coverage but the SeaTRAX does not need to be incorporated into the user s system during calibration SeaTRAX User Manual r01 Page 10 e The number of calibration sample points and the calibration pattern is dependent on the calibration method 5 1 Magnetic Calibration Two fundamental types of magnetic distortion exist hard iron distortion and soft iron distortion These are discussed in the following two paragraphs plus a discussion on how temperature also effects magnetic distortions For more information on magnetic distortion and calibration see PNI s white paper Local Magnetic Distortion Effects on 3 Axis Compassing at PNI s website http www pnicorp com technology papers Hard Iron Effects Hard iron distortions are caused by permanent magnets and magnetized steel or iron objects within close proximity to the sensors This type of distortion remains constant and in a fixed location relative to the sensors for all heading orientations
59. nicorp com at time of order acceptance be free from defects in material and workmanship and will operate in accordance with PNI s published specifications and documentation for the Product in effect at time of order PNI will make no changes to the specifications or manufacturing processes that affect form fit or function of the Product without written notice to the OEM however PNI may at any time without such notice make minor changes to specifications or manufacturing processes that do not affect the form fit or function of the Product This warranty will be void if the Products serial number or other identification marks have been defaced damaged or removed This warranty does not cover wear and tear due to normal use or damage to the Product as the result of improper usage neglect of care alteration accident or unauthorized repair THE ABOVE WARRANTY IS IN LIEU OF ANY OTHER WARRANTY WHETHER EXPRESS IMPLIED OR STATUTORY INCLUDING BUT NOT LIMITED TO ANY WARRANTY OF MERCHANTABILITY FITNESS FOR ANY PARTICULAR PURPOSE OR ANY WARRANTY OTHERWISE ARISING OUT OF ANY PROPOSAL SPECIFICATION OR SAMPLE PNI NEITHER ASSUMES NOR AUTHORIZES ANY PERSON TO ASSUME FOR IT ANY OTHER LIABILITY If any Product furnished hereunder fails to conform to the above warranty OEM s sole and exclusive remedy and PNI s sole and exclusive liability will be at PNI s option to repair replace or credit OEM s account with an amount equal to the
60. ooonnnnnnnonnonononnnnnnnnonnnnnanonononnnonons 39 7 4 3 FIR A o E 42 7 4 4 Since Mode ist 45 7 4 5 SAVING gn 46 7 5 Calibr tion Conadi caia eg 46 7 5 1 User Calibration CommandS iia ii 46 7 5 2 Performing a User calibration eee ee 48 7 5 3 EH ege 49 7 5 4 Reset to Factory Calibration cccccccccsssssssececeeeeessessneeeeeeeens 50 7 6 Operation Commandes 51 7 6 1 Data Acquisition Parameters see eee ee ee eee ee eee 51 7 6 2 Data COMPONENTS ooocccnnnncccccnnnnconnnnnnnnnnnnnnnanonnnnnnnononnnnncnncnnnnnnnnns 52 7 6 3 Making a Measurement eee eee ee eee ee eee 54 7 6 4 Sleep Mode siii de 55 7 7 Code Examples escocia it ti 56 7 7 1 Header File amp CRC 16 Function 56 7 7 2 CommProtocol A hilera Es 59 7 7 3 CommProtocol cpp File 61 7 7 4 Sea RAM eege ici 65 7 7 5 SOSA TRAX COp RI 66 SeaTRAX User Manual r01 Page ii List of Tables Table 3 1 Performance Characteristics 3 Table 3 2 I O Characteristics 4 Table 3 3 Electrical Requirements 4 Table 3 4 Environmental Requirements 4 Table 3 5 Mechanical Characteristics 5 Table 4 1 SEATRAX Pin Descriptions 6 Table 5 1 Magnetic Calibration Mode Summary 12 Table 5 2 12 Point Full Range Calibration Pattern 14 Table 5 3 12 Point 2D Calibration Pattern 15 Table 5 4 12 Point Limited Tilt Calibration Pattern 15 Table 5 5 6 Point Hard Iron Only Calibration Pattern 16 Table 6 1 Mounting Orientations 22 Table 7 1 UART Configuration 34 Table 7 2 SeaTRAX Command Set 37 Tab
61. ower cycle PNI Sensor Corporation DOC 1018154 r01 SeaTRAX User Manual October 2012 Page 27 Note If a calibration is aborted all the score s will read 179 80 and the calibration coefficients will not be changed Clicking the lt Save gt button will not change the calibration coefficients 6 4 3 Current Configuration These indicators mimic the pertinent selections made on the Configuration tab 6 4 4 Options This window indicates how many samples are to be taken and provides real time heading pitch and roll information if HPR During Calibration is set to lt On gt both as defined on the Configuration tab Audible Feedback If selected PNI Studio will give an audible signal whenever a calibration sample point is taken 6 45 Clear Clear Mag Cal to Factory This button clears the user s calibration of the magnetometers Once selected the module reverts to its factory magnetometer calibration To save this action in nonvolatile memory click the lt Save gt button It is not necessary to clear the current calibration in order to perform a new calibration Clear Accel Cal to Factory This button clears the user s calibration of the accelerometers Once selected the module reverts back to its factory accelerometer calibration To save this action in non volatile memory click the lt Save gt button It is not necessary to clear the current calibration in order to perform a new calibration SeaTRAX U
62. price paid for any such Product which fails during the applicable warranty period provided that 1 OEM promptly notifies PNI in writing that such Product is defective and furnishes an explanation of the deficiency ii such Product is returned to PNI s service facility at OEM s risk and expense and 111 PNI is satisfied that claimed deficiencies exist and were not caused by accident misuse neglect alteration repair improper installation or improper testing If a Product is defective transportation charges for the return of the Product to OEM within the United States and Canada will be paid by PNI For all other locations the warranty excludes all costs of shipping customs clearance and other related charges PNI will have a reasonable time to make repairs or to replace the Product or to credit OEM s account PNI warrants any such repaired or replacement Product to be free from defects in material and workmanship on the same terms as the Product originally purchased Except for the breach of warranty remedies set forth herein or for personal injury PNI shall have no liability for any indirect or speculative damages including but not limited to consequential incidental punitive and special damages relating to the use of or inability to use this Product whether arising out of contract negligence tort or under any warranty theory or for infringement of any other party s intellectual property rights irrespective of whether PNI had
63. put to true north heading by adding the declination angle to the magnetic north heading kBigEndian Config ID 64 Sets the Endianness of packets TRUE is Big Endian FALSE is Little Endian kMountingRef Config ID 104 This sets the reference orientation for the module Please refer to and Figure 4 2 for additional information kUserCalNumPoints Config ID 124 The user must select the number of points to take during a calibration The number of sample points must be within the listed Allowable Range or the module may not work properly Calibration generally is not as good if less than the Minimum Recommended is selected but may be acceptable See Section 5 for additional information SeaTRAX User Manual r01 Page 40 Table 7 4 Sample Points Number of Samples Calibration Mode INTE Minimum Range Recommended Full Range 10 to 32 12 2D Calibration 10 to 32 12 Limited Tilt Range 10 to 32 12 Hard Iron Only 4 to 32 6 Accelerometer Only 12 to 32 18 Accel and Mag 12 to 32 18 kUserCalAutoSampling Config ID 134 This flag is used during user calibration If set to TRUE the module automatically takes calibration sample points once the minimum change requirement is met If set to FALSE the module waits for kTakeUserCalSample to take a sample with the condition that a magnetic field vector component delta is greater than 5 uT from the last sample point If the user wants to have maximum control over
64. r Port h i ncl ude Processes h 9 CormHandl er is a base class that provides a callback for i ncom ng messages l ass CommHandl er 5 public Call back to be implemented in derived class virtual void Handl eCom Ul nt 8 frameType void dataPtr NULL Ulnt16 dataLen 0 ComrProtocol handles the actual serial conmunication wth the modul e Process is a base class that provides ComfProtocol wth cooperative parallel processing The Control method wll be called by a process manager on a continuous basis Ef eng CormPr ot ocol public Process public enum Frame Ds Commands kGet Mod nf o 1 kGet Modl nf oResp II 2 kSet Dat aConponent s 3 kGet Dat a II 4 kGet Dat aResp II 5 Data Component Ds kHeadi ng 5 5 type Fl oat 32 kTenper at ure 7 7 type Fl oat 32 kAccel X 21 21 type FI oat 32 kAccel Y 22 type Fl oat 32 kAccel Z 23 type Fl oat 32 kPi t ch 24 type Fl oat 32 kPol l 25 type Fl oat 32 kBuf f er Si ze 512 max size of input buffer kPacket M nSi ze 5 mn size of serial packet T TT Ber Port is a serial communication object abstracting the hardware i mpl erent ati on PNI Sensor Corporation DOC 1018154 r01 SeaTRAX User Manual October 2012 Page 59 ConmPr ot ocol CommHandl er handler NULL SerPort serPort NULL void Init Ul nt 32 baud 38400 void SendDat a
65. s Compared to fluxgate sensors that tend to dominate these markets the SeaTRAX requires much less power is smaller and provides a variety of calibration options And the accuracy of the SeaTRAX surpasses most fluxgate heading sensors While designed with oceanology markets in mind SeaTRAX can be ideal for non oceanology applications that desire its narrow form factor such as for sighting on laser range finders and far target locaters PNI recognizes not all applications allow for significant tilt during calibration so multiple calibration methods are available to ensure optimized performance can be obtained in the real world These include Full Range Calibration when gt 45 of tilt is possible during calibration 2D Calibration when constrained to calibration in a horizontal or near horizontal plane and Limited Tilt Calibration when tilt is constrained to lt 45 but gt 5 of tilt is possible PNI also recognizes conditions may change over time and to maintain superior heading accuracy it may be necessary to recalibrate the heading sensor So the SeaTRAX incorporates Hard Iron Only Calibration to easily account for gradual changes in the magnetic signature of the host system And the accelerometers can be recalibrated in the field if desired We re sure the SeaTRAX will help you to achieve the greatest performance from your system Thank you for selecting the SeaTRAX SeaTRAX User Manual r01 Page 2 3 Specifications 3 1 Chara
66. s rotated downward m Direction of Travel or Line of Sight S e Negative Ai PITCH Positive AXIS Negative Figure 4 1 Positive 8 Negative Roll and Pitch Definition SeaTRAX User Manual r01 Page 8 4 3 2 Mounting Orientation The SeaTRAX can be mounted in various orientations as shown in Figure 4 2 All reference points are based on the white silk screened arrow on the top side of the board The orientation should be programmed in the SeaTRAX using the kSetConfig command and the kMountingRef setting as described in Section 7 4 2 The default orientation is STD 0 Xx UP 90 el HEADING es LA X UP 180 cf ce STD 180 ES Gei HEADING Figure 4 2 Mounting Orientations PNI Sensor Corporation DOC 1018154 r01 SeaTRAX User Manual October 2012 Page 9 5 User Calibration To optimize the performance of the SeaTRAX such that it performs to specification it is necessary to properly calibrate both the magnetic sensors and the accelerometers in the device The magnetic sensors in the SeaTRAX are calibrated at PNI s factory in a magnetically controlled environment However sources of magnetic distortion positioned near the SeaTRAX in the user s system will distort Earth s magnetic field and should be compensated for in the host system with a user calibration Examples of such sources include ferrous metals and alloys ex iron nickel steel
67. se is generally recommended but True may be more convenient e Using the kSetConfig command set kCoeffCopySet magnetometer calibration and or kAccelCoeffCopySet accelerometer calibration These fields allow the user to save multiple sets of calibration coefficients 0 is the default e Using the kSetConfig command again set kUserCalNumPoints to the appropriate number of calibration points e Initiate a calibration using the kStartCal command Note that this command requires indentifying the type of calibration procedure for example Full Range Calibration or 2D Calibration e Follow the appropriate calibration procedure as discussed in Section 5 If kUserCalAutoSampling was set to False then send a kTakeUserCalSample command when ready to take a calibration point If kUserCalAutoSampling was SeaTRAX User Manual r01 Page 48 set to True then look for kUserCalSampCount to confirm when a calibration point has been taken During the calibration process heading pitch and roll information will be output from the SeaTRAX and this can be monitored using kGetDataResp e When the final calibration point is taken the device will present the calibration score using kMagCalScore e If the calibration score is acceptable as discussed in Section 7 5 3 save the calibration coefficients using kSave 7 5 3 Calibration Score kCalScore frame ID 18 The calibration score is automatically sent upon taking the fina
68. se of the Sample Delay is greater than the sample rate since the Sample Delay does not include the actual measurement acquisition time The default is 0 PNI Sensor Corporation DOC 1018154 r01 SeaTRAX User Manual October 2012 Page 23 Polling Delay The Polling Delay is relevant when Poll Mode is selected It represents the time delay in seconds between the completion of PNI Studio receiving one set of sampled data and requesting the next sample set If the delay is set to O then PNI Studio requests new data as soon as the previous request is fulfilled Note that the inverse of the Polling Delay is greater than the sample rate since the Polling Delay does not include the actual measurement acquisition time The default is 0 Acquire Delay The Acquire Delay sets the time between samples taken by the module in seconds This is an internal setting that is NOT tied to the time with which the module transmits data to PNI Studio or the host system Generally speaking the Acquire Delay is either set to 0 in which case the SeaTRAX is constantly sampling or set to equal either the Polling Delay or Sample Delay values The advantage of running with an Acquire Delay of 0 is that the FIR filter can run with a relatively high Tap value to provide stable and timely data The advantage of using a greater Acquire Delay is that power consumption can be reduced assuming the Sample or Polling Delay are no less than the Acquire Delay Flush Filters
69. ser Manual r01 Page 28 6 5 Test Tab PN Stadio Ver 5 U Fie Edit a Module SeaTRAX Connected I Firmware Version s901 Serial Number 1031792 SEI Um PCA Version ROWMBIPS Connection Configuration Calibration Test Log Data Graph System Log Current Reading 3D Model Heading 097 1 Pitch Roll 006 5 003 5 Contrast Acquisition Settings Module is in POLL mode Pall delay is 0 seconds Acquisition delay is 0 000 seconds d ple dela Filters are NOT flushed Module Outputis in Degrees Sync Mode 6 5 1 Current Reading Once the lt Go gt button is selected the module will begin outputting heading pitch and roll information Selecting the lt Stop gt button or changing tabs will halt the output of the module Contrast Selecting this box sets the Current Readings window to have yellow lettering on a black background rather than black lettering on a white background 6 5 2 3D Model The helicopter will follow the movement of the SeaTRAX and give a visual representation of the module s orientation assuming the Enable 3D Model Display box is selected on the Configuration tab 6 5 3 Acquisition Settings These indicators mimic the pertinent selections made on the Configuration tab PNI Sensor Corporation DOC 1018154 r01 SeaTRAX User Manual October 2012 Page 29 6 5 4 Sync Mode Sync Mode enables the module to stay in Sleep Mode until
70. t reading as the module is already awake SeaTRAX User Manual r01 Page 30 6 6 Log Data Tab PNV er 610 File Edit Module SesTRAX Connected O E N l Firmware Version s901 Serial Number 1031792 PCA Version PU IBU Connection Configuration Calibration Test Log Data Graph System Log Teks is 1 60th of a second Data Ticks Heading Pitch Heading 000879783 97 1 Pitch 000879788 97 1 Roll 000879793 97 1 MagX 000879797 97 1 Magy 000879803 97 1 MagZ 000879807 97 1 AccelX 000879810 97 1 AccelY 000879813 97 1 AccelZ 000879817 97 1 Temperature 000879821 97 1 Distortion 000879824 97 1 000879827 97 1 000879832 97 1 000879837 97 1 Heading 971 Pith 65 Roll 35 Auto Scroll PNI Studio can capture measurement data and then export it to a text file To acquire data and export it follow the procedure below e Select the parameters you wish to log in the Data window Use Shift Click and Ctrl Click to select multiple items In the screen shot above Heading Pitch and Roll were selected e Click the lt Go gt button to start logging The lt Go gt button changes to a lt Stop gt button after data logging begins e Click the lt Stop gt button to stop logging data e Click the lt Export gt button to save the data to a file e Click the lt Clear gt button to clear the data from the window Note The data logger use ticks for time reference A t
71. talin vauteadaves 19 6 2 Connection Tabacalera 20 6 2 1 Initial eege msi lada 20 6 2 2 Changing Barataria 20 6 2 3 Changing Module 21 6 3 Configuration Tab EN 21 6 3 1 Mounting Options cece ee ee ee teen ee eeeeeeeeeeeeeeeeeeeeeeeeeeees 21 6 3 2 North RORET EMC E 22 6 3 3 ENdIANESS ii 22 6 3 4 MACAU usada 23 6 3 5 Enable 3D Mode EE 23 6 3 6 a A Een 23 6 3 7 ACQUISITION Settings seisein 23 6 3 8 HPR During Calibration css esse eee eee eee 24 6 3 9 Calibration Settings eee eee eee eee eee 24 PNI Sensor Corporation DOC 1018154 r01 SeaTRAX User Manual October 2012 Page i BOLO DEPAUW EE 25 6 3 11 A tilt eth tial bl dl Hahei bh ete 25 6 4 Calibration bt cai ii 26 6 4 1 Samples cion 26 6 4 2 Calibration Results iii ida 27 6 4 3 Current Configura TTT 28 6 4 4 OPON Sic isa 28 6 4 5 A A A dE EE 28 6 5 A O O 29 6 5 1 CUERO los do 29 6 5 2 SDIMIO Nina 29 6 5 3 Acquisition Setting AEN 29 6 5 4 Syne Modeen iesin ebe eene ge Bed a a 30 6 6 kog Data Tab eria E eee 31 6 7 Graph Ta cT 32 6 8 System Log Tab in a Aa aT Sege 33 7 OPERATION WITH PNI BINARY PROTOCOL sssssccccsssseeccccsscececeesssees 34 7 1 Datagram Structure orisun arera aaa Ea a E a a 34 7 2 Parameter FOrMAtS oi inreder e ase i eaan aata tends 35 7 3 Commands amp Communication Frames esse sese ee eee eee eee e eee 37 7 4 Sets Up as l alaa CTT 38 7 4 1 Module lnFormatioan sss sees essere a 38 7 4 2 Module ConfiguratioN cccconono
72. the user s system sends a trigger to report data When so triggered the SeaTRAX will wake up report data once then return to Sleep Mode One application of this is to lower power consumption Another use of the Sync Mode is to trigger a reading during an interval when local magnetic sources are well understood For instance if a system has considerable magnetic noise due to nearby motors the Synch Mode can be used to take measurements when the motors are turned off Enter Sync Mode On the Test tab near the bottom of the screen click the Sync Mode check box to enter Sync Mode Sync Mode Output To retrieve the first reading click the lt Sync Read gt button Heading pitch and roll information will be displayed on Current Reading window If the Enable 3D Model Display box is selected on the Configuration tab then the helicopter will follow the movement as well The module will enter Sleep Mode after outputting the heading pitch and roll information To obtain subsequent readings the user should first click on the lt Sync Trigger gt button to wake up the module and then click on the lt Sync Read gt button to get the readings after which the module will return to sleep Exit Sync Mode Click on the lt Sync Trigger gt button and then uncheck the Sync Mode check box to exit Sync Mode Note that lt Sync Trigger gt sends a OxFF signal as an external interrupt to wake up the module This is not done for the firs
73. this feature 6 3 6 Filter Setting Taps The SeaTRAX incorporates a finite impulse response FIR filter to effectively provide a more stable heading reading The number of taps or samples represents the amount of filtering to be performed The user should select either 0 4 8 16 or 32 taps with zero taps representing no filtering Note that selecting a larger number of taps can significantly slow the time for the initial sample reading and if Flush Filters is selected the rate at which data is output The default setting is 32 6 3 7 Acquisition Settings Mode When operating in Continuous Acquisition Mode the SeaTRAX continuously outputs data to the host system The rate is set by the Sample Delay When operating in Poll Mode PNI Studio simulates a host system and polls the SeaTRAX for a single measurement but PNI Studio makes this request at a fixed rate which is set by the Polling Delay In both cases data is continuously output but in Continuous Mode the SeaTRAX controls the data rate while in Poll Mode the PNI Studio program controls the data rate Poll Mode is the default Sample Delay The Sample Delay is relevant when Continuous Mode is selected It is the time delay in seconds between completion of the SeaTRAX sending one set of data and the start of sending the next sample set If the delay is set to 0 then the SeaTRAX will begin sending new data as soon as the previous data set has been sent Note that the inver
74. tilt as expected during use Table 5 5 6 Point Hard Iron Only Calibration Pattern Footnote Sample Yaw Pitch Roll 1 0 max negative max negative 2 60 max positive max positive 3 120 max negative max negative 4 180 max positive max positive 5 240 max negative max negative 6 300 max positive max positive 1 For best results the tilt experienced during calibration should match that experienced in service For example if the SeaTRAX will be subject to 45 of pitch and roll when in service then max negative should be 45 and max positive should be 45 5 2 Accelerometer Calibration The SeaTRAX uses MEMS accelerometers to measure attitude This data is output as pitch and roll data Additionally the accelerometer data is critical for establishing an accurate heading reading when the SeaTRAX is tilted as discussed in the PNI white paper Tilt Induced Heading Error in a 2 Axis Compass which can be found on PNI s web site http www pnicorp com technology papers The SeaTRAX algorithms assume the accelerometers only measure the gravitational field If the SeaTRAX is accelerating this will result in the SeaTRAX calculating an inaccurate SeaTRAX User Manual r01 Page 16 gravitational vector which in turn will result in an inaccurate heading reading For this reason the SeaTRAX should be stationary when taking a measurement As previously mentioned
75. ting systems Check the PNI web page at www pnicorp com for the latest version For Windows computers copy the PNIStudio msi file onto your computer Then open the file and step through the Setup Wizard For Mac computers copy the PNIStudio zip file onto your computer This automatically places the application in the working directory of your computer The Quesa plug in also in the zip file needs to be moved to Library CFMSupport if it is not already there PNI Sensor Corporation DOC 1018154 r01 SeaTRAX User Manual October 2012 Page 19 6 2 Connection Tab IS Ver 5 1 File Edit Module SeaTRAX Connected O fS N l Firmware Version s901 s Serial Number 1031792 PCA Version RO1IBI79 Connection Configuration Calibration Test Log Data Graph System Log Computer Serial Pont COM1 Baud Rate 39400 Module Baud Rate 38400 6 2 1 Initial Connection If using the PNI dual connectorized cable ensure the batteries are well charged e Select the serial port the module is plugged into which is generally COM 1 e Select 38400 as the baud rate e Click the lt Connect gt button if the connection is not automatic Once a connection is made the Connected light will turn green and the module s firmware version serial number and PCA version will be displayed in the header section 6 2 2 Changing Baud Rate To change the baud rate e Inthe Module window select
76. to take a calibration sample point This should be repeated until the total number of samples as set on the Configuration tab are taken while changing the orientation of the module between samples as discussed in Section 5 If Automatic Sampling is checked the module will need to be held steady for a short time and then a sample automatically will be taken Once the window indicates the next number the module s orientation should be changed and held steady for the next sample Once the pre set number of samples has been taken as set on the Configuration tab the calibration is complete SeaTRAX User Manual r01 Page 26 6 4 2 Calibration Results Once the calibration is complete the Calibration Results window will indicate the quality of the calibration This may take a few seconds The primary purpose of these scores is to demonstrate that the field calibration was successful as demonstrated by a low CalScore The other parameters provide information that may assist in improving the CalScore should it be unacceptably high Mag CalScore Represents the over riding indicator of the quality of the magnetometer calibration Acceptable scores will be lt 1 for Full Range Calibration lt 2 for other methods Note that it is possible to get acceptable scores for Dist Error and Tilt Error and still have a rather high Mag CalScore value The most likely reason for this is the SeaTRAX is close to a source of local magnetic distortion th
77. to three 3 sets of accelerometer calibration coefficients in the module The default is set number 0 To store a set of coefficients first establish the set number number 0 to 2 using kAccelCoeffCopySet then perform the accelerometer calibration The coefficient values will be stored in the defined set number kSetConfigDone frame ID 19 This frame is the response to kSetConfig frame The frame has no payload kGetConfig frame ID 74 This frame queries the SeaTRAX for the current internal configuration value The payload contains the configuration ID requested Payload Config ID Ulnt8 kGetConfigResp frame ID 84 The response to kGetConfig is given below The payload contains the configuration ID and value Payload Ulnt8 ID Specific Example If a request to get the set declination angle the payload would look like Payload Declination ID Declination Angle Float32 7 4 3 FIR Filters The SeaTRAX incorporates a finite impulse response FIR filter to provide a more stable heading reading The number of taps or samples represents the amount of filtering to be SeaTRAX User Manual r01 Page 42 performed The number of taps directly affects the time for the initial sample reading as all the taps must be populated before data is output The SeaTRAX can be configured to clear or flush the filters after each measurement as discussed in Section 7 6 1 Flushing the filter clears all tap values thus purg
78. ual r01 Page 64 7 7 4 SeaTRAX h File pr agma once i ncl ude Processes h i ncl ude CommPr ot ocol h i This file contains the obj ect providing communi cation to the SeaTRAX It wll set up the module and parse packets received Process is a base class that provides SeaTRAX wth cooper ati ve parallel processing The Control method wll be called by a process manager on a continuous basi s ass SeaTRAX public Process public ConmHandl er a H a SL public SeaTRAX Ser Port serPort SeaTRAX pr ot ect ed CommPr ot ocol mom Ul nt 32 nSt ep mli me nResponseli me voi d Handl eCom Ul nt 8 frameType void dataPtr NULL Ul nt 16 dat aLen 0 void SendComr Ul nt 8 frameType void dat abr r NULL Ul nt 16 dataLen 0 void Control IE PNI Sensor Corporation DOC 1018154 r01 SeaTRAX User Manual October 2012 Page 65 7 7 5 SeaTRAX cpp File fi ncl ude SeaTRAX h i ncl ude Ti ckGenerator h nst Ulnt8 kDataCount 4 Ve will be requesting 4 components heading pitch roll and t enper at ure e This obj ect polls the SeaTRAX module once a second for heading pitch roll and tenperature SeaTRAX SeaTRAX Ser Port ser Port Process SeaTRAX Let the ConmProtocol know this object wll handle any serial data returned by the nodule mConm new ComPr ot ocol this serPort mime 0 mStep 1 SeaTRAX SeaTRAX
79. uld be set to 3 and Byte 2 should be set to 1 Payload Byte 1 Byte 2 Ulnt8 Ulnt8 kGetFIRFiltersResp frame ID 144 This is the response to kGetFIRFilters and it has the same payload definition as kSetFIRFilters SeaTRAX User Manual r01 Page 44 7 4 4 Sync Mode When the SeaTRAX operates in Sync Mode the module will stay in Sleep Mode until the user s system sends a trigger to report data When so triggered the SeaTRAX will wake up report data once then return to Sleep Mode One application of this is to reduce power consumption Another use of the Sync Mode is to trigger a reading during an interval when local magnetic sources are well understood For instance if a system has considerable magnetic noise due to nearby motors the Synch Mode can be used to take measurements when the motors are turned off kSetSyncMode frame ID 46 4 Note When Sync Mode is selected the SeaTRAX will acknowledge the change in mode and immediately trigger the Sync Mode and send a data frame This frame allows the module to be placed in Sync Mode The payload contains the Mode ID requested as given below Payload gt Mode ID Normal Mode 0 Mode ID Sync Mode 100 lt _ UlInt8 gt If the module is in Sync Mode and the user desires to switch back to Normal Mode an FFh string first must be sent followed by some minimum delay time prior to sending the kSetSyncMode frame The minimum de
80. ven below along with basic descriptions of the options Full Range Calibration magnetic only 10 0A Recommended calibration method when gt 45 of tilt is possible 2D Calibration magnetic only 20 14 Recommended when the available tilt range is limited to lt 5 Hard Iron Only Calibration magnetic only 30 1E Recalibrates the hard iron offset for a prior calibration If the local field hard iron distortion has changed this calibration can bring the module back into specification Limited Tilt Range Calibration magnetic only 404 28 Recommended calibration method when gt 5 of tilt calibration is available but tilt is restricted to lt 45 i e full range calibration is not possible Accelerometer Only Calibration 100 64 Select this when only accelerometer calibration will be performed Accelerometer and Magnetic Calibration 110 6E Selected when magnetic and accelerometer calibration will be done simultaneously Below is a complete sample packet to start a 2D Calibration kStartCal 00 09 00 00 00 14 5C F9 ByteCount Frame ID CalOption CalOption Checksum MSBs 2D Calibration Heading pitch and roll information is output via the kGetDataResp frame during the calibration process This feature provides guidance during the calibration regarding calibration sample point coverage During calibration in the kGetDataResp frame the number of data components is set to be 3 and then fo
81. west of true north Correcting for declination is accomplished by storing the correct declination angle and then changing the heading reference from magnetic north to true north Declination angles vary throughout the world and change very slowly over time For the greatest possible accuracy go to the National Geophysical Data Center web page below to get the declination angle based on your latitude and longitude http www ngdc noaa gov geomagmodels Declination jsp Magnetic When the lt Magnetic gt button is selected heading will be relative to magnetic north True When the lt True gt button is selected heading will be relative to true north In this case the declination needs to be set in the Declination window 6 3 3 Endianess Select either the lt Big gt or lt Little gt Endian button The default setting is lt Big gt See Sections 7 2 and 7 3 for additional information SeaTRAX User Manual r01 Page 22 6 3 4 Output The SeaTRAX module can output heading pitch and roll in either degrees or mils Click either the lt Degrees gt or lt Mils gt button The default is lt Degrees gt There are 6400 mils in a circle such that 1 degree 17 7778 mils and 1 mil 0 05625 degree 6 3 5 Enable 3D Model PNI Studios Test tab includes a live action 3 D rendering of a helicopter Some computer systems may not have the graphics capability to render the 3D Model for this reason it may be necessary to turn off
82. yncMode Saves the current internal configuration and any new 9 kSave EE Se user calibration coefficients to non volatile memory 16 kSaveDone Response to kSave Calibration 10 kStartCal Commands the SeaTRAX to start user calibration 11 kStopCal Commands the SeaTRAX to stop user calibration 31 kTakeUserCalSample Commands the SeaTRAX to take a sample during user calibration Sent from the SeaTRAX after taking a calibration 17 kUserCalSampleCount sample point PNI Sensor Corporation SeaTRAX User Manual October 2012 DOC 1018154 r01 Page 37 18 kCalScore Contains the mag and accel calibration scores Resets magnetometer calibration coefficients to O EI ee original factory established values 30 kSetFactoryMagCoeffDone Response to kSetFactoryMagCoeff Resets accelerometer calibration coefficients to ee TES HET original factory established values 37 kSetFactoryAccelCoeffDone Respond to kSetFactoryAccelCoeff Operation 24 kSetAcgParams Sets the sensor acquisition parameters 26 kSetAcqParamsDone Response to kSetAcqParams 25 kGetAcqParams Queries for the sensor acquisition parameters 27 kGetAcqParamsResp Response to kGetAcqParams 3 kSetDataComponents Sets the data components to be output 4 kGetData Queries the SeaTRAX for data 5 kGetDataResp Response to kGetData 214 KEE ebe oo the SeaTRAX to output data at a fixed 22 kStopContinuousMode Stops data output when in

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