I've built and deployed a refueling station - mines ore, converts it to fuel. On this station I have a robotic arm with docking ports (regular, Jr) at the end. Its purpose is to act like the fuel nozzle at a gas station for cars. Dock to a spacecraft that's landed nearby, and pump fuel into it.
The problem is, whenever they connect, the other ship flails about wildly, sometimes breaking parts and often winding up at some weird angle that makes it difficult or impossible to launch.
Reducing the docking force helps, and slllllooooooowwwwwwwwly moving the arm into the place where they dock sometimes does the trick. But more often, some kind of feedback loop between the landing suspension of and the docking arm makes it flail. If the to-be-fueled craft is light enough - and it often is, particularly before loaded with fuel - it gets thrown about like a hooked fish.
How do I reduce or eliminate this behavior?