Robust tracking controller with constraints using generalized velocity components for manipulators

Abstract

A proposed robust controller with torque constraints are presented in this article. It is shown that for a manipulator described in terms of the generalized velocity components (GVCs), given originally by Loduha and Ravani ( Transactions of the ASME Journal of Applied Mechanics 62, 216—22, 1995), one can use a simple control scheme, which guarantees position error tracking. Introducing GVCs, together with generalized joint positions, leads to first-order decoupling equations of motion instead of one second-order equation. Additionally, an interesting insight into the manipulator dynamics can be obtained. As opposed to the classical robust controller (Galicki, Studies in Automation and Information Technology 25, 83—93, 2000), the constraints in our algorithm are expressed in terms of quasi-moments. The performances of both controllers were compared on a 3-degree-of-freedom, 3-D Yasukawa-like robot.