Prerequisites

Ubuntu 20.04 with ROS1 Noetic installed, along with Python3.

1. Installing ROS IMU Dependencies

sudo apt-get install ros-noetic-imu-tools ros-noetic-rviz-imu-plugin

2. Downloading the Official Example Program

Download the ROS package from the official WIT Motion GitHub repository:

GitHub - WITMOTION/WitStandardProtocol_JY901

Extract the ROS package contents into your home directory. On Ubuntu, you need an additional package to extract RAR files:

sudo apt-get install unrar

3. Building the Workspace

cd ~/wit/wit_ros_ws/
catkin_make

If catkin_make fails due to Python version issues, use:

catkin_make -DPYTHON_EXECUTABLE=/usr/bin/python3

Fix missing dependencies if compilation fails:

pip3 install modbus_tk

Set up script permissions and source the workspace:

cd ~/wit/wit_ros_ws/src/scripts/
sudo chmod 755 *.py
source ~/wit/wit_ros_ws/devel/setup.bash
echo "source ~/wit/wit_ros_ws/devel/setup.bash" >> ~/.bashrc

4. Running the ROS Driver and Visualizing IMU Data

4.1 Identifying the USB Port

ls /dev/ttyUSB*

4.2 Configuring the Launch File

Open wit_imu.launch in the ROS package and make the following changes:

• Set type from normal to modbus
• Update value to match your USB port (e.g., /dev/ttyUSB0)
• Set baud rate to 115200 (if errors occur, try 9600)

4.3 Launching the ROS Driver

Grant USB permissions:

sudo chmod 666 /dev/ttyUSB0

Start the IMU driver:

roslaunch wit_ros_imu wit_imu.launch

4.4 Reading IMU Data

Open a new terminal and run the data acquisition script:

cd ~/wit/wit_ros_ws/src/scripts/
python3 read_imu_orientation.py

This displays real-time orientation and sensor data from the IMU.

4.5 Visualizing IMU Orientation

Launch RViz with IMU plugin visualization:

roslaunch wit_ros_imu rviz_and_imu.launch

This opens RViz dsiplaying the IMU's real-time orientation in a 3D view.