Wrench-Feasible Workspace of Mobile Cable-Driven Parallel Robots

Cable-driven parallel robots (CDPRs) hold numerous advantages over conventional parallel robots in terms of high speed and large workspace. Cable-driven parallel robots whose workspace can be further increased by the modification of their geometric architecture are known as reconfigurable cable-driven parallel robots. A novel concept of reconfigurable cable-driven parallel robots that consists of a classical cable-driven parallel robot mounted on multiple mobile bases is known as mobile CDPR. This paper proposes a methodology to trace the wrench-feasible workspace of mobile cable-driven parallel robots by determining its available wrench set. Contrary to classical cable-driven parallel robots, we show that the available wrench set of a mobile cable-driven parallel robot depends, not only on the cable tension limits but also on the static equilibrium conditions of the mobile bases. The available wrench set is constructed by two different approaches known as convex hull approach and hyperplane shifting method. Three case studies are carried out for the validation of the proposed methodology. The proposed approach is experimentally validated on a mobile cable-driven parallel robot with a point-mass end-effector and two mobile bases.