Excavator Simulation Movement and Physics

Hi everyone!

I’m trying to figure out how I can get the movement of my excavator prototype stable.
Currently, I implemented it with physics constraints and linear motors with a position drive for the pistons.
My goal is to have regular movement of the pistons with a constant speed. The base of this prototype also moves way to much because of the dynamics and springiness of the arm. (the arm should have a defined, rigid motion)
The reason why i didn’t set it up with a control rig oder animation directly is that i want to emulate the physical behaviour of the exavator when it collides with the ground (when the arm pushes against the ground, the excavator base should lift itself)

Video

Any help is welcome.
Thanks in advance.

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