Abstract：A method is presented to solve the motion coupling of cable-driven joints through movement compensation.Firstly,the constraint conditions for decoupling are deduced according to the principle of motion coupling,and a 2-DOF (degree-of-freedom) cable-driven manipulator is designed correspondingly.To analyze the influence of elastic deformation of the cable on the effectiveness of decoupling,a theoretical model of the relationship between the cable tension and the joint angle offset is established by applying the capstan equation.Finally,some corresponding experiments are carried out.Results show that the maximum angular offset of the joint is 0.72° when no external torque is loaded on the joint,and the difference between the calculated angular offset and the experimental one is less than 0.02° when a certain torque is loaded on the joint.In addition,the angular offset of the joint decreases with the increase of the preload,and the dynamic decoupling performance of the joint is still good.Therefore,the effectiveness of the proposed decoupling method and the accuracy of the joint angle offset model are verified.
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