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DMU380SA Series

User’s Manual

________________________________________________________________________

Doc# 7430-0026 Rev.01

Page 95

1759 McCarthy Blvd.

Milpitas, CA 95035

Phone: 408.964.9700

Fax: 408.854.7702

Website:

www.memsic.com

Email: [email protected]

Summary of Contents for DMU380SA Series

Page 1: ...puts RS 232 or RS 422 Interface Update Rate 1Hz to 100Hz Miniature Package 41 x 48 x 22mm Wide Input Voltage Range 9 32VDC Low Power Consumption 350 mW Wide Temp Range 40C to 85C High Reliability MTBF 50k hours Environmentally Protected Enclosure The MEMSIC AHRS380SA integrates highly reliable MEMS 6DOF inertial sensors and 3 axis magnetic sensors with extended Kalman filtering in a miniature fact...

Page 2: ... to display record playback and analyze all of the AHRS380SA Attitude Heading Reference System parameters NAV VIEW can also be used to set a wide range of user configurable fields in the AHRS380SA to optimize the system performance for highly dynamic applications NAV VIEW software is available for download from MEMSIC s website at www memsic com support This product has been developed exclusively ...

Page 3: ...DMU380SA Series USER MANUAL Document Part Number 7430 0026 01 MEMSIC Inc 1759 McCarthy Blvd Milpitas CA 95035 Tel 408 964 9700 Fax 408 854 7702 email infoca memsic com website www memsic com ...

Page 4: ...ssiles rockets and or UAV s of 300km or greater range or any other activity prohibited by the Export Administration Regulations is expressly prohibited without the written consent of MEMSIC and without obtaining appropriate US export license s when required by US law Diversion contrary to U S law is prohibited 2014 MEMSIC Inc All rights reserved Information in this document is subject to change wi...

Page 5: ...e 5 2 4 Serial GPS Interface INS380SA 5 2 5 External GPS Aiding VG380SA and AHRS380SA 5 2 6 1 PPS Output Interface INS380SA 6 2 7 Sync Pulse Input Interface IMU VG and AHRS380SA 6 2 8 GPS Antenna Connection INS380SA 7 2 9 No Connection 7 2 10 Quick Digital interface connection 7 2 11 3 Installation and Operation of NAV VIEW 9 NAV VIEW Computer Requirements 9 3 1 3 1 1 Install NAV VIEW 9 Connection...

Page 6: ...80SA Magnetometer Calibration and Alignment 32 4 4 2 AHRS380SA Advanced Settings 33 4 4 3 AHRS380SA Built In Test 36 INS380SA Theory of Operation 37 4 5 4 5 1 INS380SA Magnetometer Calibration and Alignment 39 4 5 2 INS380SA Advanced Settings 39 4 5 3 INS380SA Built In Test 40 5 Application Guide 42 Introduction 42 5 1 Fixed Wing Aircraft 42 5 2 Rotorcraft 43 5 3 Land Vehicle 43 5 4 Water Vehicle ...

Page 7: ...t 0 Detailed BIT and Status Packet 55 Output Packets Polled or Continuous 55 7 4 7 4 1 Scaled Sensor Data Packet 0 55 7 4 2 Scaled Sensor Data Packet 1 Default IMU Data 56 7 4 3 Angle Data Packet 1 Default AHRS Data 57 7 4 4 Angle Data Packet 2 Default VG Data 58 7 4 5 Nav Data Packet 0 59 7 4 6 Nav Data Packet 1 Default INS Data 60 8 Advanced Commands 62 Configuration Fields 62 8 1 Continuous Pac...

Page 8: ... 9 12 comStatus Field 75 9 13 softwareStatus Field 76 9 14 sensorStatus Field 76 9 15 Configuring the Master Status 76 9 16 9 16 1 hardwareStatusEnable Field 76 9 16 2 comStatusEnable Field 77 9 16 3 softwareStatusEnable Field 77 9 16 4 sensorStatusEnable Field 77 10 Appendix A Mechanical Specifications 78 11 Appendix B NMEA Message Format 80 GGA GPS fix data 80 11 1 12 Appendix C Sample Packet Pa...

Page 9: ...DMU380SA Series User s Manual Doc 7430 0026 Rev 01 Page v 14 3 4 Marking 93 14 3 5 Return Shipping Address 94 Warranty 94 14 4 ...

Page 10: ...re given throughout the manual to help the reader understand the terminology IMPORTANT This symbol defines items that have significant meaning to the user WARNING The user should pay particular attention to this symbol It means there is a chance that physical harm could happen to either the person or the equipment The following paragraph heading formatting is used in this manual 1 Heading 1 1 1 He...

Page 11: ...overview of all of the functions and features of your DMU380SA Series system For example if you have purchased a INS380SA you should read not only the section on the INS380SA but also familiarize yourself with the theory of operation for the IMU380SA VG380SA and AHRS380SA The INS380SA builds on the capabilities of the IMU380SA VG380SA and AHRS380SA Section 5 Application Guide Customers who want pr...

Page 12: ...se sensors are based on rugged field proven silicon bulk micromachining technology Each sensor within the cluster is individually factory calibrated for temperature and non linearity effects during MEMSIC s manufacturing and test process using automated thermal chambers and rate tables Coupled to the 6 DOF MEMS inertial sensor cluster is a high performance microprocessor that utilizes the inertial...

Page 13: ...rtial Systems is new to MEMSIC s product lines and provides a significant size reduction and performance improvement The DMU380SA Series has a secondary optional use communications port for internal or external GPS 1 3 3 Software Compatibility MEMSIC s DMU380SA Series Inertial Systems are software compatible with the MEMSIC 440 series products and 350 series products The DMU380SA Series products u...

Page 14: ...cted to the I O connector shell in order to provide improved EMI protection The cable sent with the unit is intended to provide the user with the ability to test the unit right out of the box and will not provide adequate shielding for all environments WARNING The cable sent with the unit is intended to provide the user with the ability to test the unit right out of the box and will not provide ad...

Page 15: ...s outputs data in NMEA 0183 format as defined by the National Marine Electronics Association NMEA Standard For Interfacing Marine Electronic Devices Version 2 20 January 1 1997 The packets are sent at 9600 Baud 8 data bits 1 start bit 1 stop bit no parity bit and no flow control and are output over the secondary serial interface RS 232 on pins 4 and 6 The GPS receiver outputs the following message...

Page 16: ...h pull up resistor between 1k and 10k ohms The INS380SA Series products synchronize sensor data collection to this 1PPS signal internally when available Therefore the 100Hz navigation algorithm will run exactly 100 times each second with no slip when locked to 1PPS Packet data is valid on the rising edge of 1PPS and 10ms boundaries thereafter There is however up to 500µs of additional latency in s...

Page 17: ...a in band jamming or a poor RF cable The DMU380SA Series unit ships with an external active antenna that must be connected properly to SMA jack located next to the DB 15 connector Placing the antenna on a 4 inch or larger ground plane is highly recommended IMPORTANT Place the antenna with optimal sky visibility and use a ground plane Route the GPS Antenna RF cable away from sources of radiated ene...

Page 18: ..._____________________________________________________________________ Doc 7430 0026 Rev 01 Page 8 Table 6 DB 9 COM Port Connections COM Port Connector DMU380SA Series Connector Pin Signal Pin Signal 2 RxD 5 TxD 3 TxD 3 RxD 5 GND 9 GND ...

Page 19: ...he CD ROM drive 2 Locate the NAV VIEW folder Double click on the setup exe file 3 Follow the setup wizard instructions You will install NAV VIEW and NET 2 0 framework Connections 3 2 The DMU380SA Series Inertial Systems products are shipped with a cable to connect the DMU380SA Series to a PC Serial port 1 Connect the 9 pin micro DB connector end of the digital signal cable to the port on the DMU38...

Page 20: ...the power supply and verify that the COM port is not occupied by another device 4 Under the View menu you have several choices of data presentation Graph display is the default setting and will provide a real time graph of all the DMU380SA Series data The remaining choices will be discussed in the following pages Data Recording 3 4 NAV VIEW allows the user to log data to a text file txt using the ...

Page 21: ...yback Mode from the Data Source drop down menu at the top 2 Selecting Playback mode will open a text prompt which will allow users to specify the location of the file they wish to play back All three file formats are supported Engineering Hex and Raw for playback In addition each time recording is stopped started a new section is created These sections can be individually played back by using the ...

Page 22: ...ng and angle information see Table 2 NAV VIEW can provide a compass and a simulated artificial horizon view To activate these views simply select Horizon View and or Compass View from the View drop down menu at the top of the page See Figure 5 Figure 5 Horizon and Compass View Packet Statistics View 3 8 Packet statistics can be obtained from the View menu by selecting the Packet Statistics option ...

Page 23: ...s the values in the left column of boxes There are three tabs within the Unit Configuration menu General Advanced and BIT Configuration The General tab displays some of the most commonly used settings The Advanced and BIT Configuration menus provide users with more detailed setting information that they can tailor to meet their specific needs To alter a setting simply select the check box on the l...

Page 24: ...trongly encouraged to read and thoroughly understand the consequences of altering the settings in the Advanced tab before making changes to the unit configuration These settings are discussed in detail in Chapter 4 below Behavior switches are identified at the top of the page with marked boxes A blue box will appear if a switch has been enabled similar to Figure 8 below The values can be set in th...

Page 25: ...ers to alter the logic of individual status flags that affect the masterStatus flag in the master BITstatus field available in most output packets By enabling individual status flags users can determine which flags are logically OR ed to generate the masterStatus flag This gives the user the flexibility to listen to certain indications that affect their specific application The masterFail and all ...

Page 26: ...t Iron Overview The AHRS and INS380SA products use magnetic sensors to compute heading Ideally the magnetic sensors would be measuring only earth s magnetic field to compute the heading angle In the real world however residual magnetism in your system adds to the total magnetic field measured This residual magnetism called hard iron and soft iron will create errors in the heading measurement if it...

Page 27: ...nt in your system using a two dimensional algorithm The AHRS and INS380SA products will calculate the hard iron magnetic fields and soft iron corrections and store these as calibration constants in the EEPROM The Mag Alignment Procedure should always be performed with the AHRS or INS380SA product installed in the user system If you perform the calibration process with the DMU380SA Series product b...

Page 28: ...completed your rotation you will be given data concerning the calibration accuracy The X and Y offset values indicate how far the magnetic field has been offset due to hard iron affects from components surrounding the unit In addition you will see a soft iron ratio indicating the effect of soft iron on the AHRS or INS380SA product 6 Save this data to the AHRS or INS380SA product by selecting the A...

Page 29: ...ill restore this functionality The magnetometer ranges is 4 gauss thus 2 5 gauss is the recommended maximum hardiron that should be tolerated for the installation and still provide ample resolution and headroom to properly determine the earth s magnetic field strength 0 5 gauss If the hard iron estimates are larger than 2 5 gauss then a different installation location should be investigated Read U...

Page 30: ...DMU380SA Series User s Manual ________________________________________________________________________ Doc 7430 0026 Rev 01 Page 20 ...

Page 31: ...lock diagram At the core of the DMU380SA Series is a rugged 6 DOF Degrees of Freedom MEMS inertial sensor cluster that is common across all members of the DMU380SA Series The 6 DOF MEMS inertial sensor cluster includes three axes of MEMS angular rate sensing and three axes of MEMS linear acceleration sensing These sensors are based on rugged field proven silicon bulk micromachining technology Each...

Page 32: ...vailable in the measurement packet or via the special Status Packet T0 As shown in the software block diagram the DMU380SA Series has a unit setting and profile block which configures the algorithm to user and application specific needs This feature is one of the more powerful features in the DMU380SA Series architecture as it allows the DMU380SA Series to work in a wide range of commercial applic...

Page 33: ...ift correction for the attitude i e roll and pitch only is a 3 axis accelerometer This is the default configuration for the VG product X Y Z Body Accelerometers 6 DOF Sensor Cluster Sensor Calibration Axes Rotation GPS Data Internal External Kalman Filter and Dynamic State Model Integration to 100 Hz Velocity GPS Position Output Hard Soft Iron Calibration UseMags X Y Z Magnetometers INS AHRS only ...

Page 34: ...is configurable with either NAV VIEW or by sending the appropriate serial commands These configurable elements are known as Advanced Settings This section of the manual describes the default coordinate system settings of the DMU380SA Series when it leaves the factory With the DMU380SA Series product connector facing you and the mounting plate down the axes are defined as follows Figure 16 DMU380SA...

Page 35: ...sitive for a positive rotation around the z axis turn right The angles are defined as standard Euler angles using a 3 2 1 system To rotate from the body frame to an earth level frame roll first then pitch and then yaw The position output from GPS is represented in Latitude Longitude and Altitude LLA convention on the WGS84 Ellipsoid This is the most commonly used spherical coordinate system The GP...

Page 36: ...efault Comments Baud Rate 38 400 baud 9600 19200 57600 also available Packet Type S0 S1 also available Packet Rate 100Hz This setting sets the rate at which selected Packet Type packets are output If polled mode is desired then select Quiet If Quiet is selected the IMU380SA will only send measurement packets in response to GP commands Orientation See Fig 12 To configure the axis orientation select...

Page 37: ...ld Bits Meaning Category masterFail 0 0 normal 1 fatal error has occurred BIT HardwareError 1 0 normal 1 internal hardware error BIT comError 2 0 normal 1 communication error BIT softwareError 3 0 normal 1 internal software error BIT Reserved 4 7 N A masterStatus 8 0 nominal 1 Alert Sensor Over Range Status hardwareStatus 9 Disabled Status comStatus 10 Disabled Status softwareStatus 11 Disabled St...

Page 38: ...te the X and Y gyro rate bias Because the gravity vector has no horizontal component the EKF has no ability to estimate either the yaw angle error or the Z gyro rate bias The VG380SA adaptively tunes the EKF feedback in order to best balance the bias estimation and attitude correction with distortion free performance during dynamics when the object is accelerating either linearly speed changes or ...

Page 39: ...y installations the Z axis vibration level is much higher than in the X and Y axes and it can prove helpful to filter the Z axis at a lower cutoff than the X and Y axes Freely Integrate OFF The Freely Integrate setting allows a user to turn the VG380SA into a free gyro In free gyro mode the roll pitch and yaw are computed exclusively from angular rate with no kalman filter based corrections of rol...

Page 40: ...a BIT word 2 bytes transmitted in every measurement packet In addition there is a diagnostic packet T0 that can be requested via the Get Packet GP command which contains a complete set of status for each hardware and software subsystem in the VG380SA See Sections 6 and 7 for details on the T0 packet The BIT word contained within each measurement packet is detailed below The LSB Least Significant B...

Page 41: ...improved performance At a fixed 200Hz rate the AHRS380SA continuously maintains the digital IMU data as well as the dynamic roll pitch and heading As showing in Figure 10 after the Sensor Calibration Block the IMU data is passed to the Integration to Orientation block The Integration to Orientation block integrates body frame sensed angular rate to orientation at a fixed 200 times per second withi...

Page 42: ...ng the GP Get Packet command The AHRS400 supports the same scaled sensor and angle mode packet format of the VG380SA The AHRS380SA defaults to the A1 Angle Packet which outputs the roll angle pitch angle yaw angle and digital IMU data In the AHRS380SA the A1 packets contain accurate magnetometer readings See Sections 6 and 7 of the manual for full packet descriptions IMPORTANT For proper operation...

Page 43: ...380SA in a vehicle for instance and the vehicle is magnetic you will still see errors arising from the magnetism of the vehicle The AHRS380SA must be calibrated after installation and prior to use of the system The AHRS380SA also provides a command interface for initiating the hard iron soft iron calibration without the using NAV VIEW The user can send a WC command to initiate the calibration and ...

Page 44: ...DMU380SA Series User s Manual ________________________________________________________________________ Doc 7430 0026 Rev 01 Page 34 ...

Page 45: ...If the AHRS380SA has been in freely integrate mode for less than sixty seconds the algorithm will resume operation at normal gain settings 2 If the AHRS380SA has been in freely integrate mode for greater than sixty seconds the algorithm will force a reset and reinitialize with high gains automatically Use Mags ON The Use Mags setting allows users to turn on and off the magnetometer feedback for ya...

Page 46: ...de correction are reduced because they are likely corrupted BIT See 4 4 3 4 4 3 AHRS380SA Built In Test As with the IMU380SA and VG380SA the Built In Test capability allows users of the AHRS380SA to monitor health diagnostic and system status information of the unit in real time The Built In Test information consists of a BIT word 2 bytes transmitted in every measurement packet In addition there i...

Page 47: ...uring a turn In other words the turnSwitch will turn on the softwareStatus bit In the AHRS380SA the turnSwitch is by default set at 0 5 deg sec about the Z axis INS380SA Theory of Operation 4 5 The INS380SA supports all of the features and operating modes of the IMU VG AHRS380SA and it includes an additional internal WAAS capable GPS receiver and associated software running on the ARM processor fo...

Page 48: ...ends on the antenna s view of the sky and the number of satellites in view The ARM performs time triggered trajectory propagation at 100Hz and will synchronize the sensor sampling with the GPS UTC Universal Coordinated Time second boundary when available As with the AHRS380SA and VG380SA the algorithm has two major phases of operation Immediately after power up the INS380SA uses the accelerometers...

Page 49: ...g 12 To configure the axis orientation select the desired measurement for each axes NAV VIEW will show the corresponding image of the INS380SA so it easy to visualize the mode of operation See section 8 4 Orientation Field settings for the twenty four possible orientation settings The default setting points the connector AFT Filter Settings 20 Hz accels 20 Hz rates The low pass filters are set to ...

Page 50: ... accelerometer feedback heavily This setting is recommended when the source of over range is likely to be sustained and potentially much greater than the rate sensor operating limit Large and sustained angular rate over ranges result in unrecoverable errors in roll and pitch outputs An unrecoverable error is one where the EKF can not stabilize the resulting roll and pitch reading If the over range...

Page 51: ...rammable alerts in the INS380SA Table 15 INS380SA Default BIT Status Definitions BITstatus Field Bits Meaning Category masterFail 0 0 normal 1 fatal error has occurred BIT HardwareError 1 0 normal 1 internal hardware error BIT comError 2 0 normal 1 communication error BIT softwareError 3 0 normal 1 internal software error or magAlignOutofBounds BIT Reserved 4 7 N A masterStatus 8 0 nominal 1 one o...

Page 52: ... INS380SA Recommended Settings Dynamic Condition Pre launch or known straight and level un accelerated flight Launch Normal Dynamics Default High Dynamics UseMags ON ON ON ON UseGPS ON ON 4g ON ON 4g FreelyIntegrate OFF OFF OFF OFF 2g Stationary Yaw Lock OFF OFF OFF OFF Restart Over Range ON OFF OFF OFF Dynamic Motion OFF ON ON ON Turn Switch Threshold 0 5 deg s 0 5 deg s 0 5 deg s 0 5 deg s XY Fi...

Page 53: ...ed advanced settings for two different dynamic conditions Table 17 Recommended Advanced Settings for Rotorcraft Recommended Product AHRS380SA or INS380SA Recommended Settings Dynamic Condition Normal Dynamics High Dynamics with uncoordinated tail motion UseMags ON ON UseGPS ON ON 4g FreelyIntegrate OFF OFF 2g Stationary Yaw Lock OFF OFF Restart Over Range OFF ON Dynamic Motion ON ON Turn Switch Th...

Page 54: ...r Accel 5 Hz 5 Hz Filter Rate Sensor 20 Hz 20 Hz When not in distorted magnetic environment Water Vehicle 5 5 Water vehicle is a craft or vessel designed to float on or submerge and provide transport over and under water Table 19 provides the recommended advanced settings for two different types of application Table 19 Recommended Advanced Settings for Water Vehicle Recommended Product INS380SA Re...

Page 55: ...imb is the phase of a flight after take off consisting of getting the aircraft to the desired flight level altitude More generally the term climb means increasing the altitude The aircraft is under vertical acceleration until it reaches the steady state climb rate Straight and level flight is the phase of flight in which an aircraft reaches its nominal flight altitude and maintains its speed and a...

Page 56: ... VIEW can be made available under certain conditions Please contact your MEMSIC representative for more information General Settings 6 1 The serial port settings are RS232 with 1 start bit 8 data bits no parity bit 1 stop bit and no flow control Standard baud rates supported are 9600 19200 38400 and 57600 Common definitions include A word is defined to be 2 bytes or 16 bits All communications to a...

Page 57: ... with PK All other communications with the DMU380SA Series unit require the 2 byte CRC Note A DMU380SA Series unit will also respond to a ping command using the full packet formation with payload 0 and correctly calculated CRC Example 0x5555504B009ef4 6 3 1 Packet Header The packet header is always the bit pattern 0x5555 6 3 2 Packet Type The packet type is always two bytes long in unsigned short ...

Page 58: ...e See Appendix C for sample code that implements the 16 bit CRC algorithm 6 3 6 Messaging Overview Table 21 summarizes the messages available by DMU380SA Series model Packet types are assigned mostly using the ASCII mnemonics defined above and are indicated in the summary table below and in the detailed sections for each command The payload byte length is often related to other data elements in th...

Page 59: ...t Data Continuous or Polled S0 0x5330 30 Scaled Sensor 0 Data Output Message AHRS INS S1 0x5331 24 Scaled Sensor 1 Data Output Message ALL A1 0x4131 32 Angle 1 Data Output Message AHRS INS A2 0x4132 30 Angle 2 Data Output Message VG AHRS INS N0 0x4E30 32 Nav 0 Data Output Message VG AHRS INS N1 0x4E31 42 Nav 1 Data Output Message VG AHRS INS Advanced Commands WF 0x5746 numFields 4 1 Write Fields R...

Page 60: ...DMU380SA Series User s Manual ________________________________________________________________________ Doc 7430 0026 Rev 01 Page 50 GF 0x4746 numFields 4 1 Get Fields Response Reply Message ALL ...

Page 61: ...ommand 7 1 3 Echo Command Echo CH 0x4348 Preamble Packet Type Length Payload Termination 0x5555 0x4348 N echo payload CRC U2 The echo command allows testing and verification of the communication link The unit will respond with an echo response containing the echo data The echo data is N bytes long 7 1 4 Echo Response Echo Payload Contents Byte Offset Name Format Scaling Units Description 0 echoDat...

Page 62: ...e Packet Type Length Termination 0x5555 0x4152 0x00 CRC U2 The unit will send this packet in response to an algorithm reset command 7 2 4 Calibrate Command Calibrate WC 0x5743 Preamble Packet Type Length Payload Termination 0x5555 0x5743 0x02 WC payload CRC U2 This command allows the user to perform various calibration tasks with the DMU380SA Series See the calibration command table below for deta...

Page 63: ...555 0x5743 0x02 WC payload CRC U2 The unit will send this packet in response to a calibrate request if the procedure can be performed or initiated WC Payload Contents Byte Offset Name Format Scaling Units Description 0 calibrationRequest U2 The requested calibration task 7 2 6 Calibration Completed Parameters Response Calibrate Completed CD 0x4344 Preamble Packet Type Length Payload Termination 0x...

Page 64: ...nString 8 bit Ascii values followed by the firmware part number string delimited by a whitespace ID Payload Contents Byte Offset Name Format Scaling Units Description 0 serialNumber U4 Unit serial number 4 modelString SN Unit Version String 4 N 0x00 U1 Zero Delimiter 7 3 2 Version Data Packet Version Data VR 0x5652 Preamble Packet Type Length Payload Termination 0x5555 0x5652 5 VR payload CRC U2 T...

Page 65: ...nmentalBIT U2 Hardware Environmental BIT Field 8 comBIT U2 communication BIT Field 10 comSerialABIT U2 Communication Serial A BIT Field 12 comSerialBBIT U2 Communication Serial B BIT Field 14 softwareBIT U2 Software BIT Field 16 softwareAlgorithmBIT U2 Software Algorithm BIT Field 18 softwareDataBIT U2 Software Data BIT Field 20 hardwareStatus U2 Hardware Status Field 22 comStatus U2 Communication...

Page 66: ...e 22 zRateTemp I2 200 2 16 deg C Z rate temperature 24 boardTemp I2 200 2 16 deg C CPU board temperature 26 GPSITOW U2 truncated ms GPS ITOW lower 2 bytes Not implemented 28 BITstatus U2 Master BIT and Status 7 4 2 Scaled Sensor Data Packet 1 Default IMU Data Scaled Sensor Data S1 0x5331 Preamble Packet Type Length Payload Termination 0x5555 0x5331 0x18 S1 payload CRC U2 This packet contains scale...

Page 67: ... Data Packet 1 Default AHRS Data Angle Data A1 0x4131 Preamble Packet Type Length Payload Termination 0x5555 0x4131 0x20 A1 payload CRC U2 This packet contains angle data and selected sensor data scaled in most cases to a signed 2 16 2 s complement number Data involving angular measurements include the factor pi in the scaling and can be interpreted in either radians or degrees Angles scaled to a ...

Page 68: ... 20 2 16 g Z accelerometer 18 xMag I2 20 2 16 Gauss X magnetometer 20 yMag I2 20 2 16 Gauss Y magnetometer 22 zMag I2 20 2 16 Gauss Z magnetometer 24 xRateTemp I2 200 2 16 Deg C X rate temperature 26 timeITOW U4 1 ms DMU ITOW sync to GPS Not Implemented 30 BITstatus U2 Master BIT and Status 7 4 4 Angle Data Packet 2 Default VG Data Angle Data A2 0x4132 Preamble Packet Type Length Payload Terminati...

Page 69: ...0 2 16 deg C Y rate temperature 22 zRateTemp I2 200 2 16 deg C Z rate temperature 24 timeITOW U4 1 ms DMU ITOW sync to GPS Not Implemented 28 BITstatus U2 Master BIT and Status 7 4 5 Nav Data Packet 0 Nav Data N0 0x4E30 Preamble Packet Type Length Payload Termination 0x5555 0x4E30 0x20 N0 payload CRC U2 This packet contains navigation data and selected sensor data scaled in most cases to a signed ...

Page 70: ...m GPS altitude 100 16284 28 GPSITOW U2 truncated ms GPS ITOW lower 2 bytes Not Implemented 30 BITstatus U2 Master BIT and Status 7 4 6 Nav Data Packet 1 Default INS Data Nav Data N1 0x4E31 Preamble Packet Type Length Payload Termination 0x5555 0x4E31 0x2A N1 payload CRC U2 This packet contains navigation data and selected sensor data scaled in most cases to a signed 2 16 2 s complement number Data...

Page 71: ...Corrected I2 7 pi 2 16 1260 2 16 rad s sec Z angular rate corrected 12 xAccel I2 20 2 16 g X accelerometer 14 yAccel I2 20 2 16 g Y accelerometer 16 zAccel I2 20 2 16 g Z accelerometer 18 nVel I2 512 2 16 m s North velocity 20 eVel I2 512 2 16 m s East velocity 22 dVel I2 512 2 16 m s Down velocity 24 longitudeGPS I4 2 pi 2 32 360 2 32 Radians GPS Longitude 28 latitudeGPS I4 2 pi 2 32 360 2 32 Rad...

Page 72: ...ta from Table 22 below Table 22 Configuration Fields configuration fields field ID Valid Values description Packet rate divider 0x0001 0 1 2 5 10 20 25 50 quiet 100Hz 50Hz 25Hz 20Hz 10Hz 5Hz 2Hz Unit BAUD rate 0x0002 0 1 2 3 9600 19200 38400 57600 Continuous packet type 0x0003 Any output packet type Not all output packets available for all products See detailed product descriptions Unused 0x0004 G...

Page 73: ...tting for the DMU380SA orientation field is Ux Uy Uz as shown in Figure 18 below With this default orientation X is defined as opposite where the connector is pointing Z is down through the base and Y is created by making the final orthogonal axis right hand rule The user axis set is X Y Z as defined by this default orientation field loaded at the factory but this can be changed as per Table 24 Fi...

Page 74: ... fly user interaction with behavioral aspects of the algorithm See Figure 26 Table 26 DMU380 Behavior Switches Description Bits Meaning Free Integrate 0 0 use feedback to stabilize the algorithm 1 6DOF inertial integration without stabilized feedback for 60 seconds Use Mags 1 0 Do not use mags to stabilize heading heading will run open loop or be stabilized by GPS track 1 Use mags to stabilize hea...

Page 75: ...io 0x000B U2 2 2 16 The hard iron bias values are scaled from 1 1 Gauss These values are subtracted from the tangent plane magnetometer vector before heading is calculated The soft iron scale ratio is scaled from 0 2 and is multiplied by the tangent plane x magnetometer value before heading is calculated Heading Track Offset 8 7 This field is used to set the offset between vehicle heading and vehi...

Page 76: ...error response Note that both a write fields and an error response may be received as a result of a write fields command Attempts to write a field with an invalid value is one way to generate an error response A table of field IDs and valid field values is available in Section 8 1 WF Payload Contents Byte Offset Name Format Scaling Units Description 0 numFields U1 The number of fields to write 1 f...

Page 77: ...se Note that both a set fields and an error response may be received as a result of one set fields command Attempts to set a field with an invalid value is one way to generate an error response A table of field IDs and valid field values is available in Section 8 1 SF Payload Contents Byte Offset Name Format Scaling Units Description 0 numFields U1 The number of fields to set 1 field0 U2 The first...

Page 78: ...ad fields command RF Payload Contents Byte Offset Name Format Scaling Units Description 0 numFields U1 The number of fields to read 1 field0 U2 The first field ID to read 3 field1 U2 The second field ID to read U2 More field IDs to read numFields 2 1 Field U2 The last field ID to read Read Fields Response 8 10 Read Fields RF 0x5246 Preamble Packet Type Length Payload Termination 0x5555 0x5246 1 nu...

Page 79: ...received as the result of a get fields command GF Payload Contents Byte Offset Name Format Scaling Units Description 0 numFields U1 The number of fields to get 1 field0 U2 The first field ID to get 3 field1 U2 The second field ID to get U2 More field IDs to get numFields 2 1 Field U2 The last field ID to get Get Fields Response 8 12 Get Fields GF 0x4746 Preamble Packet Type Length Payload Terminat...

Page 80: ...rrors are those which must be triggered multiple times within a specified time window to be considered fatal Soft errors are managed using a digital high pass error counter with a trigger threshold The masterStatus flag is a configurable indication as determined by the user This flag is asserted as a result of any asserted alert signals which the user has enabled The hierarchy of BIT and Status fi...

Page 81: ...gorithmBIT Field initialization overRange missedIntegrationStep dataError softwareDataBIT Field calibrationCRCError magAlignOutOfBounds masterStatus hardwareStatus hardwareStatus Field unlocked1PPS enabled by default on INS unlockedInternalGPS enabled by default on INS noDGPS unlockedEEPROM comStatus comStatus Field noExternalGPS enabled by default on VG and AHRS softwareStatus softwareStatus Fiel...

Page 82: ...intermediate signals that are used to determine when the masterStatus flag is asserted hardwareStatus sensorStatus comStatus and softwareStatus masterStatus is the logical OR of these intermediate signals Each of these intermediate signals has a separate field with individual indication flags Each of these indication flags can be enabled or disabled by the user Any enabled indication flag will tri...

Page 83: ...of bounds Soft inpVoltage 2 0 normal 1 out of bounds Soft fiveVolt 3 0 normal 1 out of bounds Soft threeVolt 4 0 normal 1 out of bounds Soft twoVolt 5 0 normal 1 out of bounds Soft twoFiveRef 6 0 normal 1 out of bounds Soft sixVolt 7 0 normal 1 out of bounds Soft grdRef 8 0 normal 1 out of bounds Soft Reserved 9 15 N A hardwareEnvironmentalBIT Field 9 5 The hardwareEnvironmentalBIT field contains ...

Page 84: ...le 35 contains flags that indicate low level errors with external serial port B the aiding serial port The serialBError flag in the comBIT field is the bit wise OR of this comSerialBBIT field Table 35 DMU380 Serial Port B BIT Field comSerialBBIT Field Bits Meaning Category transmitBufferOverflow 0 0 normal 1 overflow Soft receiveBufferOverflow 1 0 normal 1 overflow Soft framingError 2 0 normal 1 e...

Page 85: ...y a WE command Hard magAlignOutOfBounds N A Parameter not implemented in this software version N A Reserved 2 15 N A hardwareStatus Field 9 12 The hardwareStatus field contains flags that indicate various internal hardware conditions and alerts that are not errors or problems See Table 39 The hardwareStatus flag in the BITstatus field is the bit wise OR of the logical AND of the hardwareStatus fie...

Page 86: ...e not errors or problems See Table 42 The sensorStatus flag in the BITstatus field is the bit wise OR of the logical AND of the sensorStatus field and the sensorStatusEnable field The sensorStatusEnable field is a bit mask that allows the user to select items of interest that will logically flow up to the masterStatus flag Table 42 DMU380 Sensor Status Field sensorStatus Field Bits Meaning overRan...

Page 87: ...field 9 16 3 softwareStatusEnable Field This field is a bit mask of the softwareStatus field see BIT and status definitions This field allows the user to determine which low level softwareStatus field signals will flag the softwareStatus and masterStatus flags in the BITstatus field Any asserted bits in this field imply that the corresponding softwareStatus field signal if asserted will cause the ...

Page 88: ...ies User s Manual ________________________________________________________________________ Doc 7430 0026 Rev 01 Page 78 10 Appendix A Mechanical Specifications Figure 19 DMU380SA Series Outline Drawing IMU VG AHRS ...

Page 89: ...DMU380SA Series User s Manual ________________________________________________________________________ Doc 7430 0026 Rev 01 Page 79 Figure 20 DMU380SA Series Outline Drawing INS ...

Page 90: ...I String Description Format Example GPGGA string GPGGA Message ID GGA protocol header hhmmss ss hhmmss sss 092725 00 UTC Time Current time Latitude dddmm mmmm 4717 11399 Latitude Degrees minutes N character N N S Indicator N north or S south Longitude dddmm mmmm 00833 91590 Longitude Degrees minutes E character E E W indicator E east or W west FS 1 digit 1 Position Fix Indicator See Table below No...

Page 91: ...nual ________________________________________________________________________ Doc 7430 0026 Rev 01 Page 81 CR LF End of message Fix Status Description 0 No fix Invalid 1 Standard GPS 2D 3D 2 Differential GPS 6 Estimated DR Fix ...

Page 92: ...or retrieving 2 bytes from the queue without popping peekByte for retrieving a byte from the queue without popping Pop discard item s from queue Size returns number of items in queue Empty return 1 if queue is empty 0 if not Full return 1 if full 0 if not full The parser will parse the queue looking for packets Once a packet is found and the CRC checks out the packet s fields are placed in the XBO...

Page 93: ...w_packet unsigned short packet_type char length unsigned short crc char data 256 XBOW_PACKET QUEUE_TYPE circ_buf FUNCTION process_xbow_packet looks for packets in a queue ARGUMENTS queue_ptr is pointer to queue to process result will contain the parsed info when return value is 1 RETURNS 0 when failed 1 when successful int process_xbow_packet QUEUE_TYPE queue_ptr XBOW_PACKET result unsigned short ...

Page 94: ...through minimum length packet if Size queue_ptr 7 return 0 get data length 5th byte of packet dataLength peekByte queue_ptr 4 make sure we can read through entire packet if Size queue_ptr 7 dataLength return 0 check CRC myCRC calcCRC queue_ptr 2 dataLength 3 packetCRC peekWord queue_ptr dataLength 5 if myCRC packetCRC bad CRC on packet remove the bad packet from the queue and return Pop queue_ptr ...

Page 95: ...to queue holding area to be CRCed startIndex is offset into buffer where to begin CRC calculation num is offset into buffer where to stop CRC calculation RETURNS 2 byte CRC unsigned short calcCRC QUEUE_TYPE queue_ptr unsigned int startIndex unsigned int num unsigned int i 0 j 0 unsigned short crc 0x1D0F non augmented inital value equivalent to augmented initial value 0xFFFF for i 0 i num i 1 crc p...

Page 96: ...tval 0 if queue_ptr count MAXQUEUE retval 0 queue is full else queue_ptr count queue_ptr rear queue_ptr rear 1 MAXQUEUE queue_ptr entry queue_ptr rear item retval 1 return retval FUNCTION DeleteQeue return an item from the queue ARGUMENTS item will hold item popped from queue queue_ptr is pointer to the queue RETURNS returns 0 if queue is empty 1 if successful int DeleteQueue char item QUEUE_TYPE ...

Page 97: ...y firstIndex return byte FUNCTION peekWord returns 2 byte word from buffer without popping ARGUMENTS queue_ptr is pointer to the queue to return word from index is offset into buffer to which word to return RETURNS 2 byte word REMARKS does not do boundary checking please do this first unsigned short peekWord QUEUE_TYPE queue_ptr unsigned int index unsigned short word firstIndex secondIndex firstIn...

Page 98: ...FUNCTION Size ARGUMENTS queue_ptr is pointer to the queue RETURNS return the number of items in the queue int Size QUEUE_TYPE queue_ptr return queue_ptr count FUNCTION Empty ARGUMENTS queue_ptr is pointer to the queue RETURNS return 1 if empty 0 if not int Empty QUEUE_TYPE queue_ptr return queue_ptr count 0 FUNCTION Full ARGUMENTS queue_ptr is pointer to the queue RETURNS return 1 if full 0 if not...

Page 99: ...eries User s Manual ________________________________________________________________________ Doc 7430 0026 Rev 01 Page 89 13 Appendix D Sample Packet Decoding Figure 21 Example payload from Angle Data Packet 2 A2 ...

Page 100: ...DMU380SA Series User s Manual ________________________________________________________________________ Doc 7430 0026 Rev 01 Page 90 Figure 22 Example payload from Scaled Data Packet 1 S1 ...

Page 101: ...DMU380SA Series User s Manual ________________________________________________________________________ Doc 7430 0026 Rev 01 Page 91 Figure 23 Example payload from Nav Data Packet 1 N1 ...

Page 102: ...ca memsic com Non U S Refer to website www memsic com Return Procedure 14 3 14 3 1 Authorization Before returning any equipment please contact MEMSIC to obtain a Returned Material Authorization number RMA Be ready to provide the following information when requesting a RMA Name Address Telephone Fax Email Equipment Model Number Equipment Serial Number Installation Date Failure Date Fault Descriptio...

Page 103: ...ipping containers were discarded use heavy boxes with adequate padding and protection 14 3 3 Sealing the Container Seal the shipping container s with heavy tape or metal bands strong enough to handle the weight of the equipment and the container 14 3 4 Marking Please write the words FRAGILE DELICATE INSTRUMENT in several places on the outside of the shipping container s In all correspondence pleas...

Page 104: ...______________________ Doc 7430 0026 Rev 01 Page 94 14 3 5 Return Shipping Address Use the following address for all returned products MEMSIC Inc 1759 McCarthy Blvd Milpitas CA 95035 Attn RMA Number XXXXXX Warranty 14 4 The MEMSIC product warranty is one year from date of shipment ...

Page 105: ...nual ________________________________________________________________________ Doc 7430 0026 Rev 01 Page 95 1759 McCarthy Blvd Milpitas CA 95035 Phone 408 964 9700 Fax 408 854 7702 Website www memsic com Email infoca memsic com ...

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