where is the controller from /cmd_vel to the force applied to robot?

Question

It seems to me that what ros provides us to control a robot is the expected velocity /cmd_vel, but from this signal to real force/torque applied to the robot, there must be a controller there. Can someone tell me in which file I can see this controller? Thanks.

Actually, I'm not dealing with hardware yet. I mean the pure simulation. e.g. the husky simulator, the /cmd_vel finally goes to the gazebo husky model, and the gazebo model returns the effect of the control. in the rqt_graph i can see the there is a controller between the /cmd_vel and gazebo, but i just cannot find the file which describes it.

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Originally posted by lochlomond on ROS Answers with karma: 61 on 2019-08-26

Post score: 0

Answer 1

The method of converting velocity to force will be fully dependent on the hardware involved with the robot. Depending on which robot you have there may be a driver already supported that will handle the actual hardware. On the ROS WIKI pages there are lists of robots already supported and on github you will find more with a carefully worded google search. Or possibly you'll have to create your own if you have a custom.

If you're looking for just general example of HW control, you can find code for raspberry pi or arduino that will be very simple and easy to understand (relatively). Finding code for an industrial robot would be difficult I guess and professional code likely much more complicated.

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Originally posted by billy with karma: 1850 on 2019-08-26

This answer was ACCEPTED on the original site

Post score: 0

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Original comments

Comment by lochlomond on 2019-08-26:
sorry, i did not state the question clear enough. I updated it.