=[ Xsens MTi driver for ROS 2.0]============================================================
Documentation:
You can find the full documentation in "
Prerequisites:
Building:
Copy bluespace_ai_xsens_mti_driver folder into your ROS 2.0 workspace 'src' folder. Make sure the permissions are set to o+rw on your files and directories.
Build Xsens MTi driver package: $ colcon build
Source workspace: $ source install/setup.bash
Note: Building of 'xspublic' from the ament workspace has been automated in the CMake script. To build it manually, run the following from the ROS2.0 workspace root: $ pushd src/bluespace_ai_xsens_ros_mti_driver/lib/xspublic && make && popd
Changes in this release compared to the Xsens ROS 1.0 driver open source:
Running:
Configure your MTi device to output desired data (e.g. for display example - orientation output)
Launch the Xsens MTi driver from your ament workspace: $ ros2 launch bluespace_ai_xsens_mti_driver xsens_mti_node.launch.py
After the device has been detected, you can communicate with it from another process / terminal window.
For example:
$ ros2 topic echo /filter/quaternion
This will result in a continuous stream of data output:
---
header:
seq: 1386351
stamp:
secs: 1545223809
nsecs: 197252179
frame_id: "imu_link"
quaternion:
x: 0.00276306713931
y: 0.00036825647112
z: -0.89693570137
w: -0.442152231932
---
There is also an example that shows a 3D visualization of the device (orientation data should be enabled in the device): $ ros2 launch bluespace_ai_xsens_mti_driver display.launch.py
Compatibility:
Notes:
ROS timestamps The data messages from devices are time stamped on arrival in the ROS driver. When collecting data at higher rates, eg 100 Hz, the times between reads can differ from the configured output rate in the device. This is caused by possible buffering in the USB/FTDI driver.
For instance:
10 us, 10 us, 10 us, 45 ms, 10 us, 10 us, 10 us, 39 ms, 10 us, etc.
instead of
10 ms, 10 ms, 10 ms, 10 ms, 10 ms, 10 ms, 10 ms, 10 ms, 10 ms, etc.
Work-around: for accurate and stable time stamp information, users can make use of the sensor reported time stamp (/imu/time_ref) instead.
-[ Troubleshooting ]------------------------------------------------------------
- The Mti1 (Motion Tracker Development Board) is not recognized.
Support for the Development Board is present in recent kernels. (Since June 12, 2015).
If your kernel does not support the Board, you can add this manually
$ sudo /sbin/modprobe ftdi_sio
$ echo 2639 0300 | sudo tee /sys/bus/usb-serial/drivers/ftdi_sio/new_id
- The device is recognized, but I cannot ever access the device -
Make sure you are in the correct group (often dialout or uucp) in order to
access the device. You can test this with
$ ls -l /dev/ttyUSB0
crw-rw---- 1 root dialout 188, 0 May 6 16:21 /dev/ttyUSB0
$ groups
dialout audio video usb users plugdev
If you aren't in the correct group, you can fix this in two ways.
1. Add yourself to the correct group
You can add yourself to it by using your distributions user management
tool, or call
$ sudo usermod -G dialout -a $USER
Be sure to replace dialout with the actual group name if it is
different. After adding yourself to the group, either relogin to your
user, or call
$ newgrp dialout
to add the current terminal session to the group.
2. Use udev rules
Alternatively, put the following rule into /etc/udev/rules.d/99-custom.rules
SUBSYSTEM=="tty", ATTRS{idVendor}=="2639", ACTION=="add", GROUP="$GROUP", MODE="0660"
Change $GROUP into your desired group (e.g. adm, plugdev, or usb).
- The device is inaccessible for a while after plugging it in -
When having problems with the device being busy the first 20 seconds after
plugin, purge the modemmanager application.
Acknowledgement: Thank you to Steven Gies and his engineering team at Xsens Technologies for testing this driver against their complete MTi IMU product portfolio and reviewing the driver source.