Hi everyone!

I need to simulate a two-link structure connected by hinges which allow rotation in Z-direction in the Rigid Body Dynamics module with all the bodies considered rigid. I want to prescribe an input rotation to the revolute joint connected to the ground and observe the resulting moments and behaviour of the structure.

In order to make the simulation more realistic, I want to include nonlinear stiffness characteristic of the joints and I also want to include the friction in joints. Revolute joint supports friction, but only a single value for joint stiffness.

So far, I have managed to implement the nonlinear stiffness characteristic by using the general joint with all DOFs but rotZ fixed between a dummy rigid body and the actual link scoped by remote point. I will then apply the input rotation condition to the rigid cylinder and the rotation will transfer to the actual link as a moment including the nonlinear stiffness. Problem is, that if I use the general joint instead of a revolute joint, I lose the option of specifying a friction to the joint.

I also tried to use a torsional spring instead of a general joint which would allow me to input friction in the revolute joint, but the torsional spring does allow only a single value for stiffness.

Do you have any idea how to implement the friction and nonlinear stiffness characteristics together?