Underactuated cable-driven robots: Machine, control and suspended bodies

Abstract

This paper introduces a novel family of robots that consist of cablesuspended bodies whose motion is not fully constrained. The robots are underactuated and exhibit a pendulum-like behavior. Based on the dynamicmodel, a technique is proposed to allow the planning of point-to-point trajectories with zero-velocity landing by making the robot swing itself similarly to children on playground swings. A three-degree-of-freedom planar robot is studied as an example and a prototype of the robot and its controller are presented. Experimental results clearly demonstrate the effectiveness of the proposed control technique. Underactuated cable-suspended robots have the potential to lead to low-cost solutions in applications that require the performance of point-to-point trajectories in a large workspace. © 2010 Springer-Verlag Berlin Heidelberg.