Vision based PID control on a planar cable robot

In this paper, a visual measuring system is implemented for task space control of a planar cable robot. Since cables are able to apply only tensile forces, the proposed control algorithm shall be designed such that the cables remain in tension in the whole workspace. Furthermore, the position and orientation (pose) of the end-effector in task space coordinates shall be measured directly for precise motion control of the robot. Therefore, in this paper, vision-based measurement system is implemented on a planer cable robot and these measurements are directly used in a controller. Furthermore, the vector of internal forces is used to ensure that all cables remain in tension. Finally, The effectiveness of the proposed control algorithm is examined through some experiments on a planar cable robot and it is shown that the proposed control algorithm is able to provide suitable performance in practice.