Question about Frames in ROS

In case of a physical robot,(the one I am building is Ackermann vehicle) we only get linear velocity and steer angle. In order to publish on odometry what is the conversion involved to make it a twist msg…?? As I am new to this ros, what frames should I create to link my robot to ROS environment. I searched a Lot in the construct website, all of them are based on the simulated robot. Can you please provide me the solution in steps.

Question by Gourav Moger


So twist message has to elements: angular ( x, y, z )and linera( x, y, z ). The conversion should be based on the car chassis frame its linear speed and its angular rotation in the three AXIS XYZ, respect to the odometry frame.

So the only frames you need are the odom rame and the chasis frame. You could also need some frames for the wheels and the different sensors that you have mounted on the robot, so that afterwards RVIZ can render the laser, camera dn so on data in the sceen.

Hope it helped