Research On The Design Method And Applied Experiment Of Motor Adaptive Upper Limb Exoskeleton Robot System For Rehabilitation

Along with the accelerated aging process of China,the existing health care and facilities cannot meet the need for motor rehabilitation in stroke patient.Traditional manual assisted rehabilitation therapy mainly depends on the experience and labour intensity of therapist,which hardly satisfies the required long-duration and high intensity repetitive movement training.During the last twenty years,robotics has gained a totally new application and development in the motor rehabilitation area.Exoskeleton owns the same kinematic structure as human limb,and forms a close loop of energy and information with human through the physical interaction and cognitive interaction.Compared with the manual therapy,exoskeleton provides a long-time training with many advantages including high repeatable precision,data visualization and diverse modalities,etc.As a result,many countries have paid a great effort to develop the rehabilitation exoskeleton.In China,there are a large number of stroke patients accompanied with a weak foundation for motor therapy,so the development of exoskeleton for rehabilitation is significant in science and has a promising application.The thesis aims at the application and need of human-machine interaction in upper limb exoskeleton by analyzing the physiological motor system,and solves the key technologies and difficulties in motor adaptive physical interaction and cognitive interaction.The thesis analyzes the motor control system of human upper limb.and obtains the physiological structure and motor control theory based on the nerve-muscle-bone system.A description of shoulder,elbow and wrist joint motion is obtained.Special attention is paid on the spatial postion of glenohumeral center of rotation in shoulder complex.A seven degrees-of-freedom kinematic model is built and parameterized.The drinking movement is adopted to analyze the redundancy and solution of motor control.The motor adaptive physical interaction means that the mechanical joint adapts to the physiological joint in terms of coincidence of center of rotation(CoR)or axis.The thesis utilizes the motion capture system and functional method to quantify the position of shoulder CoR under different humeral orientation.The traditional three degrees-of-freedom ball-and-socket joint is optimized through translation of axes of shoulder flexion/extension and abduction/adduction,which forms a spatial curve of mechanical CoR.An index of CoR compatibility is defined to characterize the matching between mechanical CoR and anatomical CoR.The optimized translation parameters are used for the design of the motor adaptive ball-and-socket joint.The interaction force of human-machine interface decreases after optimization,which validates the feasibility and effectiveness of motor adaptive ball-socket joint in improve compatibility of human-machine kinematic close loop.The upper limb physiological motor control system owns redundancy in task space,joint space and muscl space.The synergistic motor pattern is an effective way for the central nerve system(CNS)to handle redundancy.Principal component analysis is used to analyze the upper limb joint synergy of a specific task,point to point movement.Three princinpal components and subspace are obtained to explain 95%data information.The linear synergistic motor pattern of main joints is obtained to support the design of cognitive interaction.The motor adaptive cognitive interaction indicates that in order for the stroke patient adapts to the normal joint synergies and corrects the abnormal joint synergies,the main joints of a exoskeleton robot adapt to each other and accomplish the task in coordination.Four rehabilitation training modalities,including the repeteative,mirror,teaching and task movement training,are developed and implemented in upper limb exoskeleton system.Based on the motor adaptive physical interaction and cognitive interaction,the upper limb rehabilitation exoskeleton system is realized through three aspects including mechanical structure,intelligent control strategy and human-machine interface.Experiments are carried out to validate the functionality and reliability of the exoskeleton system,which provide reliable theoretical basis and technical assistance for further research and application.