Docking ports + robotic parts = uncontrolled bouncing

[WalnutCreekTom]

I want to use robotic parts to connect two landed vessels, for example, a stationary mining rig and a rover with tanks that could transport converted fuel to a nearby landed ship. Using robotic parts sounds like a good way to deal with alignment issues - just extend and pivot until the two docking parts are aligned. However, when I try, the smaller part that gets docked starts bouncing uncontrollably. Has anyone done this successfully?

[AHHans]

5 hours ago, WalnutCreekTom said:

Has anyone done this successfully?

I think I did this after a fashion with this craft: ETS. But I didn't encounter the problems you describe.

My guess(!) is that after docking one of the crafts pushes the other one into the ground, and then the landing gear (or legs or wheels) start their (usual ) jumping around. What could help is: a) not having the stationary mining rig on landing legs, but on girders with grip pads. (I.e. retract the legs after landing.) And / or b) reduce the torque on the robotic parts so that they can barley lift the docking boom that they are supposed to move. (In the hope that this will reduce the stress on the landing gear.)

[WalnutCreekTom]

Thanks for your reply! I'll check out that craft.

My initial theory was that the robot parts had their various set points, but then the magnetic pull of the docking ports forced the actual positions away from the set points, so that when the parts tried to go back to their set points they got into this positive (bad) feedback loop. I tried dialing around the dampening settings and the torque, to no avail. 

I'll keep experimenting – I'd really like to figure out how to make this work.

 

[AHHans]

4 hours ago, WalnutCreekTom said:

My initial theory was that the robot parts had their various set points, but then the magnetic pull of the docking ports forced the actual positions away from the set points, so that when the parts tried to go back to their set points they got into this positive (bad) feedback loop.

In my limited experience the "bounciness" of the robotic parts is a lot less bad than the bounciness of the landing gear. I think that is because the restoring force of the robotic parts is not a (badly modeled) spring but the engine power of said part. Thus my suggestion to mitigate this by reducing the mechanical load on the landing gear.