Robot model¶
This tutorial lists the main components that allow you to visualize a robot model. As the official documentation of these components is sufficient, we will only provide a brief description of each component.
tf2¶
tf2 is the second generation of the transform library. It produces so called tf frames.
These are the positions and orientations of all the parts in the urdf. The tf frames have input from the robot_state_publisher.
In case an IMU is used, the march_data_collector uses IMU data to send a transform of the imu_link to tf2.
The resulting tf frames are used by rviz for creating a visualization. The tf frames are also used in the march_data_collector to calculate the center of mass and capture point.
urdf¶
urdf is an xml format used to describe robots. It contains of visuals as well as collisions. xacro is a macro language which allows you to use variables and other neat shortcuts in urdf files. To gain practical experience, please see the official tutorials.
joint_state_publisher¶
The joint_state_publisher is a very useful package, which reads your urdf and publishes a JointState message for all your joints.
robot_state_publisher¶
The robot_state_publisher takes your urdf and the joint states, and calculates the respective tf frames.
rviz¶
rviz is a 3D visualization tool which is capable of displaying information about your robot and its surroundings. The visualization combines the urdf and the tf frames to show the robot model. Please check the official userguide to start using it!