Title :
Issues in the design of passive controllers for flexible link robots
Author :
Rossi, Mauro ; Zuo, Kai ; Miang, D.
Author_Institution :
Dept. of Electr. & Comput. Eng., Waterloo Univ., Ont., Canada
Abstract :
In this paper, issues in the design of passive controllers for flexible link robots are discussed. It is well known that, for the single flexible link manipulator, the mapping from the input torques to the joint velocities is passive whereas the mapping from the input torques to the derivative of net tip movements (the usual output chosen) is not. However, if an appropriate output variable is selected, the transfer function, can be made passive provided that the hub inertia seen by the flexible link is sufficiently small. Then, by the passivity theorem, using any strictly passive controller with finite gain will result in an L2-stable system. However, for an an industrial robot, the effective hub inertia seen by the flexible link is usually large. Alternate approaches are examined for extending these passivity results to large hub inertias. Experimental results are presented for a 5-bar-linkage manipulator with the last link being flexible
Keywords :
control system synthesis; manipulators; stability; transfer functions; 5-bar-linkage manipulator; L2-stable system; flexible link robots; hub inertia; industrial robot; input torques; joint velocities; passive controllers; passivity theorem; single flexible link manipulator; transfer function; Circuit stability; Closed loop systems; Control systems; Design engineering; Electrical equipment industry; Manipulators; Nonlinear systems; Service robots; Torque control; Transfer functions;
Conference_Titel :
Robotics and Automation, 1994. Proceedings., 1994 IEEE International Conference on
Conference_Location :
San Diego, CA
Print_ISBN :
0-8186-5330-2
DOI :
10.1109/ROBOT.1994.351275
