Controlling Motor-Current with ROS

[ThomasVoss]

Good Morning Folks,

we, at Leuphana, are trying to controll the position of the robot using a combination of ROS and Matlab on the Robot.

Specs:

Matlab 2015b
ROS Indigo - Robotino-ros-pkg
Ubuntu14.04

We have achieved that by using /cmd_vel message in ROS but would like to controll motor-current to be even better. I know there is are certain messages that can contain motor current but what would the approproate topic be?

Hope to hear from you soon,
Thomas

I got an answer:
generally posiblle; need to rewrite the mikrocontrollers firmware to implement current not only velocity control by ROS,

[misken]

A few notes from my point of view:

Despite rewriting the Robotino driver node, I guess that this doesn't make sense when using ROS. ROS doesn't (out of the box) support any other method of conrolling a robot than the /cmd_vel message. The complete navigation stack etc. is relying on this. Supposed you implement this as a firmware update then you would have to change all the ROS stuff as well.

Anyhow, controlling the robots position via the current is by far not as reliable as the odometry approach using wheel encoders. If a wheel is blocked, you still have current floating but there might be no movement of the robot.