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Dear all,

I am trying to do a steady-state analysis of a rigid body geometry with the Multibody Dynamics Module (MDM).

I set up a geometry of rigid bodies, defined all attachments and approriate hinges following the Workflow of the double pendulum tutorial. Now doing the analysis I get, that I have to constrain the bodies/hinges so they wont move (see linked thread).

However, I cannot find the correct way to do that. Constraining just the hinges or just the rigid bodies, I cannot achieve convergence or get after some iteration s a singular matrix error. Constraining both leads to a singular matrix error even before the computation starts.

The dof overview shows for all cases 0 net dofs and the respective number of net constraints is always larger than 0. Also, I find the dof analysis rather confusing. Shouldnt I be able to solve the set of equations, if the net dof is zero and therefore the system is neither under- nor overdetermined?

Any help, insights or advice you can provide is greatly appreciated.

André.

Ps: I unfortunately cannot share the model file due to security issues since this is for a work related project.