@peteroznewmannMay I ask how do I make the joint work? I tried adding translational, cylindrical and revolute joint on my hinge and the top part is still not moving as much as I thought. It is just bending as if I never add any joint. Sometimes the whole motion just glitches and skip the moving part, and went straight to showing the stress. For my Joint, I select the cylinder surface of the hinge (Green part) as the reference and two of the landing gear structure vertical surfaces as mobile.nAnd how do you use displacement to keep the leg level. Because I do have the problem of the leg sliding off.nn