Research On Control Of Upper Limb Rehabilitation Robot Based On Flexible Array Tactile Sensor

With the acceleration of population aging in China,the number of patients suffering from cerebrovascular diseases or nervous system diseases is increasing.Most of the patients are accompanied by hemiplegia symptoms and some motor dysfunction.Nowadays,scholars at home and abroad have carried out a lot of research on upper limb rehabilitation robots.And rehabilitation robots play an important role in promoting the development of rehabilitation medicine.The emergence of rehabilitation robots not only alleviates the shortage of rehabilitation physicians,but also reduces the financial burden of patients,so that effective treatment can be achieved.Rehabilitation robot,as an automatic rehabilitation medical equipment,is based on the principles of rehabilitation medicine.It provides targeted rehabilitation therapy to help patients carry out scientific and effective rehabilitation training,so that patients'motor function can be better restored.There are many kinds of exoskeleton rehabilitation robots,but the number of robots that can really achieve the rehabilitation training of all joints of the whole arm is less.Moreover,it needs to wear sensor equipment,which makes the structure of the robot complex and can not meet the basic training requirements in rehabilitation medicine.Based on the human upper limb skeletal muscle model,the structure of the upper limb rehabilitation robot is optimized.The human-machine interaction force introduced by the flexible surface tactile sensor is used to study the flexible control of the upper limb rehabilitation robot.The main research contents are as follows:(1)According to the skeletal muscle model of human upper limb,the body structure of upper limb rehabilitation robot is optimized,and the kinematics equation of upper limb rehabilitation robot is established.The weight is reduced by nearly 50%compared with the previous generation of rehabilitation robots.The correctness of kinematics model is verified by Adams and Matlab simulation analysis,and the workspace of upper limb rehabilitation robot is solved.The dynamic equation of the upper limb rehabilitation robot is established.The physical model was established by SimMechanics toolbox,and the dynamic equation was verified.(2)The structure and conductive mechanism of the array flexible tactile sensor are studied.The data acquisition system of the array flexible tactile sensor is designed,and the linearity of the array flexible tactile sensor is calibrated.The upper computer program is written by Microsoft Visual Studio 2013,which realizes the collection,processing,storage and graphical display of sensor data.Aiming at elbow and shoulder joint motion,the pressure distribution between forearm,upper arm and upper limb rehabilitation robot is obtained by flexible surface tactile sensor.A method of motion intention identification based on SVM and flexible surface tactile sensor is proposed.The parameters c and g of SVM model are optimized by grid search method,and the motion intention recognition of human upper limb is trained and tested.Experiments verify the validity of elbow and shoulder motion intention identification.(3)Taking shoulder flexion/extension joint and elbow flexion/extension joint of upper limb rehabilitation robot as control objects,the impedance control algorithm was studied and simulated,and the influence of target impedance parameters on the system was studied.In order to realize the compliance control of upper limb rehabilitation robot,the fuzzy impedance control algorithm based on dynamic model and the position-based fuzzy impedance control algorithm are proposed,and the simulation analysis is carried out.Finally,the feasibility of the position-based fuzzy impedance control algorithm is verified by experiments.