Design and Control of a Suspended Cable-Driven Parallel Robot with Four Cables

This paper addresses design and control of a new suspended under-constrained cable-driven parallel robot with four cables. In order to improve the estimation of the cable lengths, an auxiliary roller screw mechanism is utilized to move the winch linearly for proper cable coiling on one layer. Also, for the sake of obtaining the pose of the robot in real-time, an angular rate sensor is embedded on the end-effector. The collected data from the angular rate sensor is used to make equivalent the solution of the forward geometric-static problem to the solution of linear system of equations. The foregoing reduced system can be readily solved and leads to the pose of the moving platform in real-time which is a definite asset in control. Moreover, kinematic problem of the cable-driven parallel robot is provided and a new method for obtaining the forward geometric-static problem is proposed.