An Output-Feedback PID-type Global Regulator for Robot Manipulators with Bounded Inputs*

An output-feedback PID-type controller for the global stabilization of manipulators with bounded inputs is proposed. It guarantees the global regulation goal preventing input saturation while avoiding the exact knowledge of the system model and parameter values as well as the need for velocity measurements. Furthermore, it adopts an SPD-SI structure by keeping both the P and D actions together within a generalized saturation function while including an additional similar saturating integral action separately. So far, a formal analytical formulation for such a saturating PID-type control structure was not available under the absence of velocity measurements. Experimental results on a 2-degree-of-freedom direct-drive manipulator corroborate the efficiency of the proposed controller. Copyright© 2015 IFAC