Stable phase transition control for robot arm motion

A nonlinear-feedback-based algorithm is combined with explicit force control to drive a rigid manipulator from free space to compliant motion. Force control is switched on when the sensors report a contact event. An event-based motion planning method is used. Physically sensible definitions for the stability of a phase transition are given. A nonlinear interaction force model is considered in the analysis. Conditions involving impact velocity are presented for a stable phase transition that allows a finite number of bounces before final contact is eventually established. A sufficient condition for bounceless landing is given. The results are verified by dynamic simulation, which is now in the process of experimental implementation