On a Representation of Friction in Configuration Space

This article provides a geometric representation of friction for a rigid planar part with two translational and one rotational degrees of freedom. The article constructs a generalized friction cone by imbedding into the part's configuration space the force constraints that define the classic Coulomb friction cone in real space. The resulting representation provides a simple geometric method for determining the possible motions of a part subjected to an applied force and torque. The representation has been used both for simulating part motions and for planning assem bly operations. The approach generalizes to the six-dimensional configuration space of a three-dimensional part.