Extract linear velocity
Greetings, dear community! I was wondering if you could help with some questions. I'm a college student and a beginner at using ROS and Gazebo, and right now I'm trying to implement a trajectory tracking algorithm for a differential robot. I'm using as a base a open model Gazebo simulation available on https://docs.neobotix.de/display/ROSS..., and I wrote my nodes for the algorithm. The problem that I'm facing right now is I don't know from which topic of the simulation I should take the reading of the wheels previous velocities needed for the program. The last attempt I did was to subscribe to the joint topic to get the wheels angular displacement to obtain the wheel angular velocity and multiply the result by the wheel radius, and get in this way the wheel previous linear velocity. But the robot didn't performance as I was expecting. The work I've done so far can be found on https://gitlab.com/ga_07/electrical-p..., inside my_simulation directory. I will appreciate any help you can give me!