Design And Optimization Of The Hardware Control System Of Upper Limb Rehabilitation Exoskeleton

With the application of upper extremity rehabilitation exoskeleton robot in hemi-plegic rehabilitation application more and more widely,ensuring the comfort of human-machine interaction and reducing the confrontation force in human-machine interaction has gradually become a research hotspot.How to design a hardware control system that meets the conditions is a prerequisite for designing a suitable robot control system.This thesis is mainly for upper extremity rehabilitation exoskeleton robot system,and carries out research related to hardware control system,real-time capability evaluation and real-time capability optimization,including the following three aspects:Design a hardware control system for the passive,active,and impedance control modes of the upper exoskeleton.Firstly,the mechanical structure is under consideration to complete the demand analysis and design of the motion control system and interactive force acquisition system and joint absolute angle detection system.Aiming at the flange coupling joint which is difficult to detect the angle in the system by traditional methods,a hall sensor ring is designed,which combines the relative motion angle returned from the motion controller to detect the absolute angle of the joint.Finally,the design of the main control unit is carried out,real-time data exchange between the control unit and other units in the system is realized through the CAN bus and CANopen protocol.A set of system software was designed according to the system structure,and the functional design of the system was verified through interactive force experiments.In response to the needs of the control system,this paper proposes a real-time evalua-tion index of the hardware control system of the upper extremity rehabilitation exoskeleton robot based on force following control and a design method of distributed main control system based on heterogeneous control system.The system's real-time performance is evaluated by the system's response speed to force changes,and the main links and reasons that affect the system's real-time performance are obtained through experiments and anal-ysis based on the characteristics of the hardware control system and software structure.In view of the relatively independent characteristics of the hardware parts used in different links,the tasks in the control system are divided into high real-time needed tasks and low real-time needed tasks,and a design method of distributed main control system based on heterogeneous control systems is proposed.According to different control modes,differ-ent tasks that require different real-time capabilities will be processed with different mi-croprocessors,and the real-time performance of the hardware control system of the system will be optimized while ensuring system functionality and scalability.And by following the experiment on the interaction force of the optimized system,it is compared with the real-time performance of the system before optimization to verify the effectiveness of the optimization method.Finally,the real-time optimization performance of the system was quantified through the position control delay measurement experiment,and it was found that the position control delay time in this system was optimized by 47%.Then the time consumption of each link of the system before and after optimization is analyzed,and the theory of optimization method is further verified.