Frame is a connector which lies at the origin of the coordinate system attached to it. Cut-force and cut-torque act at the origin of the coordinate system and are resolved in the PlanarWorld frame. Normally, this connector is fixed to a mechanical component. But it is never used directly in a system - use either of inherited frames instead, e.g. Frame_a.
Developed 2010 at the DLR Institute of System
Dynamics and Control