why finger_mesh_in_gripper_base can change?

[xins981]

https://github.com/wenbowen123/catgrasp/blob/dc656c05da85e9e732c56a887bb665e1b2a52289/run_grasp_simulation.py#LL78C15-L78C15
In my opinion, the finger_mesh_in_gripper_base just is the transformation matrix of the finger fame to gripper frame. But I think the relative pose is constant. so why finger_mesh_in_gripper_base can change in runing run_grasp_simulation.py?

[wenbowen123]

Hi, for parallel jaw gripper, the finger pose could change based on the finger's sliding position. So we made it non-constant to be general.

[xins981]

In fact, I still don't understand. Before calculating the finger_mesh_in_gripper_base, I find the finger will open. In other word, the finger seem don't slide.