Eight-Cable Robocrane Extension for NASA JSC ARGOS

Abstract

This paper presents extension of the triangular 6-cable NIST RoboCrane to a rectangular 8-cable-suspended robot, motivated by an application in the ARGOS (Active Response Gravity Offload System) Laboratory at NASA Johnson Space Center. Six candidate cable/platform design arrangements are considered and evaluated in MATLAB simulation, based on all-eight-cable-positive tensions workspace, singularities, magnitude and slope of cable tensions during trajectories, translational/rotational stiffness, and cable interference. As ever in engineering design, there are tradeoffs, and recommendations are made as to the most suitable design out of the six candidates.