We will track here all the workarounds we came up to fix some of the problems we had.

Simulation

Diffdrive strange movement

After we implemented the diffdrive controller the rover was able to move, but only the forward and backward movement worked reliable. The turning commands resulted in a strange rectangular movement oriented like the main coordinate axis.

Fix:

We added the grousers to the wheels and each of them has its own local friction parameters.

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Rocker Bogie:

The urdf file format does not support closed loops, but for a working rocker bogie we would need one to stabilize the main body in the center.

Fix:

We assumed that the angles on both sides would be same so that the body is always exactly in the middle of the two rockers. Therefore we implemented the mimic plugin for gazebo and we used a PID controller to get it to work correctly in gravity.

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detected QRcode orientation

After we implemented the qr-code detection in the simulation we saw that the visualized markers in Rviz were not oriented correctly.

Fix:

We created another link attached to the camera and rotated so that the markers would be in the correct position. The CameraInfo would have to contain this new link so that the ar_track_alvar package would attach the markers to the right frame.