Dynamic hybrid position/force control of robot manipulators--Description of hand constraints and calculation of joint driving force

Abstract

For the application of robot manipulators to complex tasks, it is often necessary to control not only the position of a manipulator but also the force exerted by the hand on an object. For this purpose, Raibert and Craig have proposed the hybrid position/force control method. In this method, however, the manipulator dynamics has not been taken into account rigorously. The dynamic hybrid control method is proposed, which takes the manipulator dynamics into consideration. Constraints on the end effector are described by a set of constraint hypersurfaces. Then the basic equations for dynamic hybrid control are derived. It is shown that if the manipulator is not in a singular configuration, the desired position and force at the end effector can be simultaneously realized. Finally, a basic structure of the dynamic hybrid control system with a servo compensator is given.