Implement baristabot Example

[cpr-fer]

Instead of using the C++ API or implementing the entire process logic in behavior trees this PR attempts to implement the functionality in Python, utilising the very new MoveIt Python API, see here.

If a prebuilt release for humble happens in the near future I will wait to implement it. Otherwise I'll build MoveIt from source and continue working on this PR.

TODO:

• [x] Launch file
  • [x] How to start Nav2, MoveIt and Co cleanly without lots of duplicate code?
  • [x] Is it possible to use the rebel_on_platform.urdf for moveit? (#11 #14 )
• [x] Get MoveItPy to run
• [x] Add gripper communication
• [ ] Add coffee maker communication
• [ ] Improve Nav2 performance (#7 )
• [ ] Test it step by step
• [ ] Add ordering interface

[cpr-fer]

Not yet back at the state where the example was a month ago, but MoveItPy is accepting commands again. Either Pilz or the baristabot script have some issues with the path planning or positions as some of the previously working joint goals became unreachable and the reachable ones are reached with a weird joint configuration:

Screencast from 26.04.2023 12:03:03.webm

[cpr-fer]

The basic coffee brewing and picking+placing works now, and I made a few changes I want to merge into the main branch. As such it is time to split the issue into new followup subissues for the different improvements that could be done.

See #87 #88 #89 #90