Issue with "total pin joint" when the angular velocity is prescribed
When the angular velocity is prescribed within a "total pin joint", using the syntax
# ...
orientation constraint, active, active, angular velocity,
0., 0., 1., const, 40.;
the linear solver complains about the matrix being singular. If the same problem is modeled using a "total joint" that connects the same node to another node that is grounded by a "clamp" joint, no matrix singularity occurs, and the problem is correctly solved.