A much more extensive and standard ROS-style version of this documentation can be found on the ROS wiki at:
http://wiki.ros.org/razor_imu_9dof
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Install dependencies:
$ sudo apt-get install python-visual
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Download code:
$ cd ~/catkin_workspace/src $ git clone https://github.com/KristofRobot/razor_imu_9dof.git $ cd .. $ catkin_make
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For SEN-14001 (9DoF Razor IMU M0), you will need to follow the same instructions as for the default firmware on https://learn.sparkfun.com/tutorials/9dof-razor-imu-m0-hookup-guide and use an updated version of SparkFun_MPU-9250-DMP_Arduino_Library from https://github.com/lebarsfa/SparkFun_MPU-9250-DMP_Arduino_Library (an updated version of the default firmware is also available on https://github.com/lebarsfa/9DOF_Razor_IMU).
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Open
src/Razor_AHRS/Razor_AHRS.ino
in Arduino IDE. Note: this is a modified version of Peter Bartz' original Arduino code (see https://github.com/ptrbrtz/razor-9dof-ahrs). Use this version - it emits linear acceleration and angular velocity data required by the ROS Imu message -
Select your hardware here by uncommenting the right line in
src/Razor_AHRS/Razor_AHRS.ino
, e.g.
// HARDWARE OPTIONS /*****************************************************************/ // Select your hardware here by uncommenting one line! //#define HW__VERSION_CODE 10125 // SparkFun "9DOF Razor IMU" version "SEN-10125" (HMC5843 magnetometer) //#define HW__VERSION_CODE 10736 // SparkFun "9DOF Razor IMU" version "SEN-10736" (HMC5883L magnetometer) #define HW__VERSION_CODE 14001 // SparkFun "9DoF Razor IMU M0" version "SEN-14001" //#define HW__VERSION_CODE 10183 // SparkFun "9DOF Sensor Stick" version "SEN-10183" (HMC5843 magnetometer) //#define HW__VERSION_CODE 10321 // SparkFun "9DOF Sensor Stick" version "SEN-10321" (HMC5843 magnetometer) //#define HW__VERSION_CODE 10724 // SparkFun "9DOF Sensor Stick" version "SEN-10724" (HMC5883L magnetometer)
- Upload Arduino sketch to the Sparkfun 9DOF Razor IMU board
In its default configuration, razor_imu_9dof
expects a yaml config file my_razor.yaml
with:
- USB port to use
- Calibration parameters
An examplerazor.yaml
file is provided.
Copy that file to my_razor.yaml
as follows:
$ roscd razor_imu_9dof/config
$ cp razor.yaml my_razor.yaml
Then, edit my_razor.yaml
as needed
Publisher and 3D visualization:
$ roslaunch razor_imu_9dof razor-pub-and-display.launch
Publisher only:
$ roslaunch razor_imu_9dof razor-pub.launch
Publisher only with diagnostics:
$ roslaunch razor_imu_9dof razor-pub-diags.launch
3D visualization only:
$ roslaunch razor_imu_9dof razor-display.launch
For best accuracy, follow the tutorial to calibrate the sensors:
http://wiki.ros.org/razor_imu_9dof
An updated version of Peter Bartz's magnetometer calibration scripts from https://github.com/ptrbrtz/razor-9dof-ahrs is provided in the magnetometer_calibration
directory.
Update my_razor.yaml
with the new calibration parameters.
After having launched the publisher with one of the launch commands listed above, it is possible to dynamically reconfigure the yaw calibration.
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Run:
$ rosrun rqt_reconfigure rqt_reconfigure
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Select
imu_node
. -
Change the slider to move the calibration +/- 10 degrees. If you are running the 3D visualization you'll see the display jump when the new calibration takes effect.
The intent of this feature is to let you tune the alignment of the AHRS to the direction of the robot driving direction, so that if you can determine that, for example, the AHRS reads 30 degrees when the robot is actually going at 35 degrees as shown by e.g. GPS, you can tune the calibration to make it read 35. It's the compass-equivalent of bore-sighting a camera.