Add a controller for afour wheel independent steering / drive mobile base, aka a swerve drive

[pvandervelde]

I would like to add a controller for a 4 wheel independent steering and independent drive (aka swerve drive) mobile base. In this kind of mobile base each wheel has two degrees of freedom, one for moving the wheel around its axle and one for the steering motion of the wheel. Each wheel is independently controllable from the other wheels.

There have been several attempts at creating ROS controllers for such a system, e.g. ros-controls/ros_controllers#441, https://github.com/MarkNaeem/ros_controllers/tree/noetic-devel/swerve_steering_controller and #1148.

I have created a proof of concept for one such drive in python. Additionally I have created a simple simulation tool to test different control algorithms.

If there is interest I would like to implement a swerve controller for ROS2 control.

[christophfroehlich]

Hi @pvandervelde!
Your contribution would be highly appreciated. I see that you started documenting the kinematics, as a first step you could add your documentation here and then build your controller upon that nomenclature.

[pvandervelde]

@christophfroehlich That does sound like a good place to start. For the implementation process I was aiming to follow the process suggested in this comment by bmagyar. I'll reference this issue in all PRs.

I might have some questions about some parts of the library. Would those best be asked in the ROS discourse or just in this issue?

[christophfroehlich]

Either on robotics stack exchange or here.