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Document MT1600P.2019.A 

© Xsens Technologies B.V.

 

MTi Family Reference Manual 

 

4.4.5  Initialization 

The Xsens sensor fusion algorithms do not only estimate orientation, but also keeps track of variables 
such as sensor biases or properties of the local magnetic field. For this reason, the orientation output 
may need some time to stabilize once the MTi is put into measurement mode. Time to obtain optimal 
stable  output  depends  on  a  number  of  factors.  An  important  factor  determining  stabilizing  time  is 
determined  by  the  time  to  correct  for  small  errors  on  the  bias  of  the  gyroscopes.  The  bias  of  the 
gyroscope may slowly change due to different effect such as temperature change or exposure to impact. 
 

4.4.6  Filter Profile options 

As described above, the algorithm uses assumptions about the acceleration and the magnetic field to 
obtain orientation. Because the characteristics of the acceleration or magnetic field differ for different 
applications, the Xsens algorithm makes use of filter profiles to be able to use the correct assumptions 
given  the  application.  This  way,  it  can  be  optimized  for  different  types  of  movement.  For  optimal 
performance in a given application, the correct filter profile must be set by the user. Each product offer 
different filter profile options, refer to the specific documentation to know more about the filter profiles

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4.4.7  Additional setting options and features 

Table 11 summarizes the additional options offered to adapt and optimize the algorithm to cover more 
scenarios and possible corner cases. 
 
 

Table 11: Supplementary features and settings 

Active Heading 
Stabilization (AHS) 

Active  Heading  Stabilization  (AHS)  is  a  software  component  within  the 
sensor fusion engine designed to give a low-drift unreferenced (not North-
referenced) yaw solution even in a disturbed magnetic environment. It is 
aimed to tackle magnetic distortions that do not move with the sensor, i.e. 
temporary or spatial distortions.  
 
AHS  is  not  tuned  for  nor  intended  to  be  used  with  GNSS/INS  devices. 
Therefore,  Xsens  discourages  the  use  of  this  feature  for  GNSS/INS 
devices.  
 
For the MTi 600-series, the AHS feature is embedded in the filter profiles. 
 
For more information on the activation and use of AHS, refer to the BASE-
article: 

BASE by Xsens - AHS tutorial

 

 

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 Datasheet for the MTi 1-series and MTi 600-series. MTi User Manual for the other Xsens MTi products 

Содержание MTi Series

Страница 1: ...67 00 fax 31 0 88 973 67 01 e mail info xsens com internet www xsens com 101 N Pacific Coast Hwy Suite 101 El Segundo CA 90245 USA phone 310 481 1800 fax 310 416 9044 e mail info xsens com internet w...

Страница 2: ...rights reserved Information in this document is subject to change without notice Xsens MVN MotionGrid MTi MTx and Awinda are registered trademarks or trademarks of Xsens Technologies B V and or its p...

Страница 3: ...2 2 Orientation increment and Velocity increment dq and dv 16 4 2 3 Orientation data 17 4 2 4 Velocity data 18 4 2 5 Position data 19 4 3 PHYSICAL SENSOR MODEL 19 4 3 1 Calibrated q and v outputs 20 4...

Страница 4: ...A Xsens Technologies B V MTi Family Reference Manual 6 INSTALLATION TIPS AND TRICKS 29 6 1 TRANSIENT ACCELERATIONS 29 6 2 VIBRATIONS 29 6 3 MAGNETIC MATERIALS AND MAGNETS 29 7 WARRANTY AND LIABILITY 3...

Страница 5: ...onents of Development Kit 11 Table 4 Description of software components of Development Kit 12 Table 5 Conditions for the use of the MT Software Suite 13 Table 6 Data outputs with reference coordinate...

Страница 6: ...s for the use of Xsens products and inside information about installation MEMS sensors and GNSS receivers hardware design CAD files system architecture low level communication and sensor fusion algori...

Страница 7: ...Surface Mount Devices SMD module The MTi 600 series is a cost effective product line for easy integration The MTi 10 series2 is Xsens entry level model with robust accuracy The MTi 100 series is a Xse...

Страница 8: ...rence for roll and pitch calculations Essentially it delivers the same data as the AHRS except for the yaw The yaw estimate of a VRU product is unreferenced which means that it is computed without any...

Страница 9: ...e information 2 2 3 MTi 10 series The MTi 10 series offers inertial and orientation data at an affordable price It features a sturdy anodized aluminium housing and robust push pull connectors The MTi...

Страница 10: ...MTi 1 IMU MTi 610 IMU MTi 10 IMU MTi 100 IMU VRU MTi 2 VRU MTi 620 VRU MTi 20 VRU MTi 200 VRU AHRS MTi 3 AHRS MTi 630 AHRS MTi 30 AHRS MTi 300 AHRS GNSS INS MTi 7 GNSS INS MTi 670 GNSS INS MTi G 710...

Страница 11: ...Development Kit Depending on the model of MTi you have purchased the Development Kit can contain any of the following items Table 3 Description of hardware components of Development Kit Component Desc...

Страница 12: ...to online manuals Xsens Device API library MFM SDK Library Library for the Magnetic Field Mapper 3 1 1 Getting Started with MT Manager software The easiest way to get started with your MTi is to use M...

Страница 13: ...edded computers and microcontrollers The low level communication is extensively described in the MT Low Level Communication Protocol Documentation3 Next to that source code is delivered to make driver...

Страница 14: ...Not allowed to reverse engineer Allowed to execute reproduce modify and compile modified source code to use with Xsens products only Not allowed to modify DLL Include License Agreement with distribut...

Страница 15: ...tings Modelling Parameters Next to the calibration values shown in MT Manager each device is calibrated according to more complicated models to ensure accuracy e g non linear temperature effect cross...

Страница 16: ...Velocity increment Sensor fixed frame Sxyz or Oxyz Orientation increment Sensor fixed frame Sxyz or Oxyz Free acceleration Local earth fixed frame LXYZ default ENU Orientation Local earth fixed frame...

Страница 17: ...gles6 roll pitch yaw XYZ Earth fixed type are output following the aerospace sequence Z Y X Rotation Matrix directional cosine matrix A positive rotation is always right handed i e defined according t...

Страница 18: ...o mounting of the MTi on the automotive platform vehicle It is recommended to always mount the MTi with the x axis pointing to the front of the vehicle irrespective of the local coordinate frame used...

Страница 19: ...ata is used to relate the sampled digital voltages u from the sensors to the respective physical quantity s The gain matrix is split into a misalignment matrix A and a gain matrix G The misalignment s...

Страница 20: ...etic field data is in sensor fixed coordinate system Sxyz or Oxyz The units of the calibrated data output are as shown in Table 9 Table 9 Output specifications inertial and magnetometer data outputs V...

Страница 21: ...019 A Xsens Technologies B V MTi Family Reference Manual 4 3 4 Free acceleration Free acceleration Data ID 0x4030 is the acceleration in the local frame LXYZ from which the local gravity is deducted T...

Страница 22: ...re are several ways to mitigate the drift in yaw rotation around the z axis 1 When the MTi has sufficient movement in roll and pitch 30 degrees for more than 10 seconds the gyroscope bias will be esti...

Страница 23: ...c disturbances refer to chapter 6 3 of this document Next to the solutions described on the article Estimating Yaw in magnetically disturbed environments to mitigate effects from magnetic disturbances...

Страница 24: ...e optimized for different types of movement For optimal performance in a given application the correct filter profile must be set by the user Each product offer different filter profile options refer...

Страница 25: ...e Xsens filter output Currently only the Portable default and Airborne 4g platforms are supported The platform model can be configured using MT Manager or low level communication For more details on G...

Страница 26: ...erfaces for each product are available in the respective datasheets or hardware integration manuals Table 12 overview of interface options in MTi portfolio Interface MTi 1 series MTi 600 series I C SP...

Страница 27: ...MEA protocol As almost all GNSS receivers support the output of NMEA messages this functionality enables the use of virtually any GNSS receiver It is important to note that when using the NMEAin both...

Страница 28: ...the filter and user inputs Information contained within the status word are for example Selftest Filter valid GNSS fix No rotation update status Representative motion Clip flags of all axis gyroscopes...

Страница 29: ...the accelerometers the following two conditions can make the readings from the accelerometers invalid 1 The magnitude of the vibration is larger than the measurement range of the accelerometer This w...

Страница 30: ...incorrectly assuming that the device has rotated However in case of continuous magnetic disturbances 10 to 30 s depending on the filter settings the computed heading will slowly converge to a new sol...

Страница 31: ...current specifications for the Product for a period of one year from the date of delivery ANY LIABILITY OF XSENS WITH RESPECT TO THE SYSTEM OR THE PERFORMANCE THEREOF UNDER ANY WARRANTY NEGLIGENCE ST...

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