Workspace Investigation of Cable-Driven Robots With Non-Negligible Cable Mass and Antipodal Method

The significance of gravity, cable density and elasticity on cable tension and manipulator workspace is investigated. Formulations of the cable tension vector are discussed. In addition, implementation of the antipodal theorem criteria for the workspace boundary characterization of planar cable-driven robot manipulators is presented when the mass and elasticity of cables are included. It is demonstrated that unlike the linear model, the external force could have more prominent effect on the workspace. Specifically, depending on the cable properties, platform orientation and manipulator design constraints, for the catenary cable model, the extended workspace due to external wrench may be divided into disjoint regions.