The fundamental concepts of robust compliant motion for robot manipulators

Abstract

Manipulators are subject to interaction forces when they maneuver in a constrained work-space. Our goal is to develop a method for the design of controllers or constrained manipulators in the presence of model, uncertainties. The controller must carry out fine maneuvers when the manipulator is not constrained, and compliant motion, with or without Interaction-force measurement, when the manipulator is constrained. At the same time stability must be preserved If bounded uncertainties are allowed in modelling the manipulators. Stability of the manipulator and environment as a whole and the preservation of stability in the face of changes are two fundamental, issues that have been considered in the design method. We start with conventional controller design specifications concerning the treatment of external forces when the manipulator is not constrained. Generalizing this concept to include cases when the manipulator is constrained, we state a set of practical, design specifications in the frequency domain that is meaningful, from the standpoint of control, theory and assures the desired compliant motion. In the cartesian coordinate frame and stability in the presence of bounded uncertainties. This approach also assures the global stability of the manipulator and its environment. While this paper concerns the fundamentals of compliant motion, part 2 of this paper [Reference 24] is devoted to the controller design method.