Strict Lyapunov functions for global regulation of robot manipulators

Proposes a systematic methodology, based on the energy shaping framework, to find strict Lyapunov functions for a class of global regulators for robot manipulators. The class of controller is described by control laws composed by a gradient of an artificial potential energy plus a linear velocity feedback. The authors provide explicit sufficient conditions on the artificial potential energy which allows them to obtain in a straightforward manner a strict Lyapunov function. Based on this technique the authors establish strict Lyapunov functions for well known regulators and propose a new one