I am looking for some parameter suggestions for a very simple task: pick up a small 2.5" cube with a two-finger pinch grip. Once the parameters are changed to make this simple grip possible, my hope is handling objects in the simulation will be much easier with other more complicated gripping patterns. Pinch grips do not perform well in MuJoCo with the default hand. The cube can be pinched, but once the hand is raised, the block slides out of the fingers. This is not a function of the block being too heavy, since I tried making the block 1/100th of the default density to no avail. I also raised tangential friction, no luck. I tried messing with the new solver parameters (also to no avail), but I am having trouble understanding how solref and solimp affect everything from object stiffness/compliance to contact interactions. I appreciate the effort to improve the documentation here, but it is still way over my head. I have a gut feeling that the underlying parameters that can improve a pinch grip are somewhere in here, but I do not know how to change them. Please reply with any suggestions, not just those limited to solref and solimp mods.