A Practical Approach for the Hybrid Joint-Space Control of Overconstrained Cable-Driven Parallel Robots

Abstract

Hybrid joint-space control of overconstrained cable-driven parallel robots requires regulating the length of as many cables as the degrees of freedom of the end-effector, and controlling the tension of the remaining ones. Previous studies showed how to choose which cables to length control, and which ones to tension control, according to minimum tension error propagation techniques. The sets of tension-controlled and length-controlled cables achieving minimum tension error propagation typically vary throughout the workspace, which is an undesirable outcome. This paper aims to achieve practicality in hybrid joint-space control, by investigating which cables to be tension-and length-controlled in the whole workspace, without needing to change such sets. The HRPCable robot at LIRMM is analyzed for this application, and experiments are carried out on it.