The Control Strategy of Flexible Cable Driven Force Interactive Robot

In order to allow astronauts to perform the virtual operation training by simulating space environment on the ground instead of in real space environment, a flexible cable driven force interactive robot combined with virtual reality (VR) technology is designed. Firstly, the configuration of the robot is designed according to the motion characteristics of the object in microgravity environment. The dynamic model of mobile platform, driving unit and human pushing process is established and the kinematics analysis is carried out. Then, a compound control strategy is proposed for the redundant drive and force control task of the system. That is, the length change of the flexible cable is the inner loop of the velocity control, and the outer loop control of force is the hybrid force/velocity control. Finally, the single flexible cable loading and man-machine system force interactive simulation analysis are carried out, respectively. The analysis results show that the constant force following error of the flexible cable driving unit can be reduced by 10% with the proposed control strategy, and the change of cosine force can be followed steadily, which verify its effectiveness for suppressing surplus force.