Research On Mechanism Design And Control Strategy Of Upper Limb Rehabilitation Robot

Nowadays,the global population aging problem is becoming more and more serious,and there are more and more patients with hemiplegia caused by stroke and other problems.Rehabilitation robot,which integrates rehabilitation medicine and robotics,has become an effective method to assist stroke patients to restore motor nerve function.Aiming at the non-repetitive and non-linear characteristics of the rehabilitation robot system,as well as the tracking accuracy and response speed of the rehabilitation robot during the training process,this paper designs a three-degree-offreedom upper limb rehabilitation robot and proposes a high-order internal mode iterative learning control algorithm to improve the control flexibility and convergence speed of the rehabilitation robot,and to reduce the fatigue of the patient’s limbs during the rehabilitation process,which is beneficial to the rehabilitation process.The main findings of this study are as follows:(1)Mechanism design of a three-degree-of-freedom upper limb rehabilitation robot.The exoskeleton-type three-degree-of-freedom upper limb rehabilitation robot mechanism was designed by analyzing the human upper limb structure,movement mode and upper limb rehabilitation needs.The robot is designed to assist patients in shoulder abduction and adduction training,shoulder flexion and extension training,and elbow flexion and extension training.(2)Kinematic and kinetic analysis of the upper limb rehabilitation robot.The kinematic analysis of the rehabilitation robot is carried out by D-H method,and the kinematic simulation is realized and the motion space of the robot arm is solved by Matlab platform;the kinetic model is established by Lagrangian method,the analytical model characteristics are studied,and the rotational torque of the robot joints is calculated;the virtual prototype of the upper limb rehabilitation robot is modeled based on Adams software,and the kinetic joint driving torque of the robot is completed.The simulation was carried out to verify the validity of the structural dynamics model of the robot.(3)Research on the control strategy of rehabilitation robot based on higher-order internal mode iterative learning.Based on the internal-mode control principle and iterative learning algorithm,a higher-order internal-mode iterative learning control strategy is designed,its control scheme is developed and its convergence is analyzed;Matlab simulation analysis shows that the proposed algorithm is verified to track the desired trajectory effectively,and the proposed higher-order internal-mode iterative learning control strategy has higher convergence efficiency and better robustness compared with the traditional iterative learning algorithm.(4)Experimental study of the upper limb rehabilitation robot.Through a well-built experimental platform of upper limb rehabilitation robot,single-joint and multi-joint rehabilitation training was conducted,and the designed rehabilitation robot system was verified to be able to complete the scheduled passive rehabilitation training based on the range of motion and tracking accuracy of the trajectory of the rehabilitation robot,and the feasibility of the three-degree-of-freedom upper limb rehabilitation robot research and the effectiveness of the proposed control method were verified.