Cylindrical coordinates or constraints

[grvaldes]

Hello everyone, I have a case where I have a ring_rod rotating on its axis, but when I joint it to other elements in the system it moves. Is there a way to work in cylindrical coordinates to I can constrain the R axis, or at least provide constraints so the ring rod can rotate staying in place? If I block the movements in the XY plane (with Z normal of the ring) it also blocks the in-plane rotations, so that is not a proper solution.

Thanks everyone in advance!