Design Method for Robust Compliant Motion for Manipulators

Abstract

This paper describes a controller-design methodology to develop a robust compliant motion for robot manipulators. The achievement of the target dynamics (the target impedance is introduced in Part one (22) 1 and preservation of stabilty robustness in the presence of bounded model uncertainties are the key issues in the design method. State-feedback and force-feedforward gains are chosen to guarantee the achievement of the target dynamics, while preserving stability in the presence of model uncertainties. In general, the closed-loop behavior of a system cannot be shaped arbitrarily over an arbitrarily wide frequency range. We prove, however, that a special class of impedances that represent our set of performance specifications are mathematically achievable through state-feedback end interaction-force feedforward and we offer a geometrical design method for achieving them in the presence of model uncertainties.