A Novel Design to Improve Pose Accuracy for Cable Robots

Abstract

Cable robots are parallel manipulators in which rigid links are replaced by cables, while actuator and transmission systems are responsible for commanding the end-effector by rolling cables in and out by means of drums and changing cable direction by means of pulleys. Commonly developed kinetostatic models assume that the robot frame and end-effector are point-to-point connected. This assumption may induce non-negligible errors in the end-effector pose when performing pick and place operations or trajectory tracking. This paper deals with a new design for connecting the frame and end-effector to reduce any modeling inaccuracies due to the aforementioned assumption. Experimental tests are presented for a planar 4 cable robot.