Kinematics Modeling and Solution of Hybrid Active-Passive Cable-driven Space Manipulator Considering the Effects of Hysteresis and Deformation

For dexterous tasks of cable-driven space manipulators in an unstructured environment, stretch of the driving cable and segment deformation hamper the precise control of these manipulators. To solve this problem, an improved kinematics model is proposed. Firstly, a kinematics model is set up on multiple mapping among the length of driving cable, the joint angle, and the end pose of the manipulator. Further, the coupling effects of three factors are considered, including the cable hysteresis, the movement direction switching and the segment deformation, and consequently the model of mapping between the length of driving cable and the joint angle is improved. Secondly, a test platform is designed, and the cable hysteresis is measured under different loads. Finally, the test data of the cable-driven space manipulator prototype are compared with the simulation results of the improved kinematics model. Comparison results with the ideal geometric model show that, the absolute position error can be reduced by 15.2 mm at the end of the two-segment cable-driven space manipulator with a length of 1110 mm, while the absolute position error of the end can be reduced by 61.4%, which proves the effectiveness of the improved kinematics model.