robot_description

This ROS 2 package provides the URDF/Xacro robot model and launch files to publish the TF tree using robot_state_publisher. While the current one is only for running through localization.

Features

• Xacro-based robot description (robot.urdf.xacro)
• Generates URDF file from Xacro
• Launch file to start robot_state_publisher
• Publishes TFs for links such as base_link, imu_link, and gps_link

Directory Structure

robot_description/
├── launch/
│  └── display.launch.py
├── urdf/
│  ├── robot.urdf.xacro
│  └── robot.urdf  # optional, generated from Xacro
├── package.xml
└── setup.py

Prerequisite

You need to download package:

sudo apt update
sudo apt install ros-humble-xacro

And go to the folder of xacro file and generate your URDF file:

cd ~/gnss_ws/src/robot_description/urdf
ros2 run xacro xacro robot.urdf.xacro -o robot.urdf

Finally, source your workspace:

cd ~/gnss_ws
source install/setup.bash

Build and run

cd ~/gnss_ws
colcon build --packages-select robot_description --event-handlers console_direct+
source install/setup.bash
ros2 launch robot_description display.launch.py

Monitoring

Generate a PDF visualization of the current TF tree (frames.pdf) for debugging the TF topology structure:

ros2 run tf2_tools view_frames

View the TF transformation (include translation and rotation) between base_link to imu_link in real time. But this require you run localization then you can view the transform.

ros2 run tf2_tools tf2_echo base_link imu_link

Check /tf topic (i.e. TF broadcast data) in real time:

ros2 topic echo /tf