Is there any recommended way to realize static joint friction these kind of friction? In my interpretation of document. Static friction are realized as constraint and frictionloss parameter limits the constraint force. And MuJoCo's soft contact feature always weight average the acceleration when the constraints exist and the one without constraints. Therefore regardless of how weak applied forces are and how large the frictionloss parameter is, if forces are non-zero, the object slightly accelerates unlike real friction with which object don't move if forces are sufficiently weak. Is my understanding correct? And possible solutions I found to realize static friction are following two ways. 1. Use Noslip solver via setting noslip_iterations>0. However, I don't know what Noslip solver really do. 2. Use higher solreffriction. It seems working but I don't know it's a realistic Coulomb friction model and how to optimize the parameter. So I also wanted to know the way to adjust these parameters. So my questions are following four, 1) Recommended way to implement joint friction 2) My understanding of frictionloss parameter is correct 3) How the Noslip option works 4) How to adjust solreffriction parameters to realize Coulomb friction Thanks.