Adaptive variable impedance position/force tracking control of fracture reduction robot

Abstract

BACKGROUND: The operation object of robot-assisted fracture reduction surgery is the musculoskeletal tissue with rigid-compliance coupling characteristics. It is necessary to improve the interactive compliance and safety between the reduction robot and the musculoskeletal tissue. METHOD: An adaptive variable impedance position/force tracking control strategy based on friction compensation is proposed. The stiffness of the reduction robot can be adaptively adjusted according to the contact force between the end-effector and the environment. The Stribeck friction force model of the branch chain electric cylinder is derived to improve the motion control performance. RESULTS: The fracture reduction experiment is completed. The experimental results show that the adaptive variable impedance position/force control strategy can realize position and force tracking in fracture reduction. CONCLUSION: A safety control strategy is proposed and applied to robot-assisted fracture reduction surgery, which improves the coordination and compliance of the human-robot interaction between the reduction robot and the patient.