Model May Be Overconstrained

Condition

Redundant constraints occur in rigid multi-body dynamics when multiple rigid joints or certain types of inputs each attempt to control one or more of the same degrees of freedom (DOF) of part. When this happens, force results for some joints may be incorrect.

Remedy

Do one of the following:

  • Remove the redundancy or conflict.
  • Use Flexible Joints, which can be used on rigid parts without over constraining.
  • Use Flexible bodies, which introduce more DOF to a part and can be used with rigid joints without being overconstrained.
  • Use Motion Contact. If proper geometry is available, modeling the joint itself using contact can result in more realistic joint behavior, as geometry and tolerances can be accounted for.
  • Use Virtual Joints. Virtual joints are similar to flexible joints, but they use a different solution approach.