Control of constrained robot systems

Abstract

This thesis focuses on the issues of control of constrained robots. The control objectives are to make the position of the robot and the constraint force to achieve their desired values under various situations which were not covered sufficiently in the past. These situations include that the constraint is in motion, that the dynamics of the constraint is unknown as well as that of the robot, and that the robota??s joint are flexible with unknown stiffness. The controller design for keeping the contact between the end effector of the robot and the constraint is studied. The issue of position/force tracking of constrained robot with impedance control is also addressed.For the controller design for each case, the dynamic model of the constrained robot system is set up and its properties are explored. Various control approaches such as nonlinear feedback, adaptive control, robust control, fuzzy control and neural network control are utilized to develop the position/force controller. Simulation study is done to verify the effectiveness of the controller developed.