Fundamental principles of design of position and force controller for robot manipulators

In this paper, fundamental principles of design of position/force controller for robot manipulators executing constrained task are enunciated. The principles are based on stability considerations, and are addressing the dynamic interaction between position and force subcontrollers. The principles could serve as design guidelines that would guarantee overall stability and reduction of the interactions between the subcontrollers. The concept of consistency introduced in this paper forms the cornerstone of proper implementation of position/force (P/F) controllers, in terms of reduction of the interaction between the two subcontrollers. The principle of consistency indicates that the direct interaction is canceled via the design of a stable P/F controller, however the indirect interaction can only be removed if a Jacobian condition is satisfied, independent of the subcontrollers design