My robot is a free-floating cube with two ur5 arms. I'd like to use one arm tip as a fixed base and the other as the end-effector but I can't because the planner always consider the base_link (the cube) as fixed.

For example, in this video the robot can't avoid obstacles because the planner seems to plan with the base (cube) being fixed to its position (see the "ghost" of the planned trajectory):
https://user-images.githubusercontent.com/7405791/241901092-c9baf0ce-491b-46b5-be83-1e57fb08f3db.mp4

Does anyone have any idea what's going on?