A Cable-Driven Parallel Robot with Full-Circle End-Effector Rotations

TL;DR

This paper introduces a hybrid cable-driven parallel robot combining a CDPR with a spherical wrist, achieving large translational and unlimited rotational workspace with reduced mass and inertia.

Contribution

It presents the design, modeling, and prototyping of a novel hybrid robot that overcomes traditional orientation workspace limitations of CDPRs.

Findings

Large translational workspace achieved

Unlimited orientation workspace demonstrated

Reduced mass and inertia of the system

Abstract

Cable-Driven Parallel Robots (CDPRs) offer high payload capacities, large translational workspace and high dynamic performances. The rigid base frame of the CDPR is connected in parallel to the moving platform using cables. However, their orientation workspace is usually limited due to cable/cable and cable/moving platform collisions. This paper deals with the design, modelling and prototyping of a hybrid robot. This robot, which is composed of a CDPR mounted in series with a Parallel Spherical Wrist (PSW), has both a large translational workspace and an unlimited orientation workspace. It should be noted that the six degrees of freedom (DOF) motions of the moving platform of the CDPR, namely, the base of the PSW, and the three-DOF motion of the PSW are actuated by means of eight actuators fixed to the base. As a consequence, the overall system is underactuated and its total mass and inertia in motion is reduced.