Position control research based on wire rope connected twin directdrive motor system

The twin direct drive motor system connected by wire rope has many advantages such as lightweight and high stiffness, widely used in light weight actuation applications. However, because of the elasticity and nonlinearity characteristic, wire rope is difficult to be used in the precise position control applications. In this paper, a novel wire rope pretightening force control strategy by dual direct drive motors is proposed to achieve high precise position control. First, the topological structure of the proposed motor system is set up. Based on this structure, the dynamic equations of the system are derived with the stability analyzed. Using Simu link tools, the position and velocity control diagram using PID algorithm is built for simulation. Then, the influence of important factors such as wire rope tension, load mass and the wire rope stiffness are analyzed in simulation. Finally, the simulation results indicate that the wire rope tension has greater influence than the other influence factors in the position tracking process. The simulation results verify the possibility of wire rope transmission in precise position control system.