Control of planar passive wire-driven support systems using servo brakes

Abstract

In this research, control of a passive wire-driven system for the physical support of human beings is discussed. The considered support system does not have any active motor and the required force for steering the system is provided by a human operator. In the cases that the handling point deviates from the desired path, the servo brake units apply force and eliminate the position error. Thus, the robot is completely safe in human–robot interaction and can be used for sports training and rehabilitation. In this article, the controllable workspace of the system for tracking some curves is obtained, a controller based on sliding mode is proposed, and a redundancy resolution method is suggested for two applications of the system. The efficiency of the control strategy is investigated by simulating the movement of the robot for each application.

Keywords:

• Passive motion and force support system
• wire-driven robots
• servo brake
• workspace
• control