Mimic joints in Gazebo

edit

Hi everyone. I am trying to simulate the popular Barrett hand in Gazebo and I am struggling to do it correctly. The problem is that out of 8 joints, 4 are actually mimicked, which leaves only 4 DOF.

I saw that this was a topic since a long time ago (e.g. here, here, or here).

Was this ever implemented? Is there any way to constrain the two joints in a transmission manner? I saw that Gazebo has support for gearbox joints. Can they be used to implement this dependency?

Thanks!