The Design And Implementation Of A Desktop Upper Limb Rehabilitation Robot Control System

In recent years,the number of stroke patients has been increasing.Moving deficit is one of the common post-stroke sequelae.At present,the most common method for recovering these lost functions is that the rehabilitation therapist trains the affected limb of the patient.With a severe shortage of rehabilitation therapists,most patients missed the best recovery period.Replacing a part of the work of a rehabilitation therapist with a robot is a good solution.The use of rehabilitation robots for rehabilitation can improve the rehabilitation effect,shorten the training period,and record various data during the training process,providing a basis for later rehabilitation evaluation.However,current upper limb rehabilitation robots have the disadvantages of low reliability,low safety,large size,single training mode,and high cost.Therefore,it is particularly important to study an upper limb rehabilitation robot that is suitable for using in small and medium-sized hospitals or patients' families.According to the theory of rehabilitation treatment of stroke,based on the analysis of research status of rehabilitation robots at home and abroad,general requirements are proposed from several perspectives of rehabilitation training function,control strategy,and safety.A new type of upper limb rehabilita tion robot was designed as required.The main tasks include the following:1?An overall plan for a desktop-type upper limb rehabilitation robot is presented.Three continuous-switching omnidirectional wheels are used as the omnidirectional mobile chassis,STM32 as the main control board.Position sensor and the force sensor are attached to the system.It can provide three modes of movements,communicate with the host computer and contact force control and position detection.The robot supports rehabilitation sports training in the home environment,which can increase recovery time and reduce rehabilitation costs.2?In order to obtain accurate robot position information,the advantages and disadvantages of common position sensors are analyzed.Optical mouse sensors are applied to the desktop positioning system by using the characteristics of high precision,real-time,and short-range positioning of photoelectric mouse sensors.The robot's kinematics and dynamics are modeled,and the double closed-loop is used to control the position of the robot.The experimental results show that the position control meets the requirements of rehabilitation training.3?In order to control the contact force of the patient to the rehabilitation robot,a DC motor model is established,and the signal collected by the 3D force sensor is filtered by an algorithm that combines the limiting filter and the first-order lag filter.Based on the analysis of conventional PID control performance,a fuzzy PID controller is designed to improve the stability and rapidity of contact force control.4?In order to make the robot flexible in the passive mode,a compliance control scheme based on position impedance is designed,which means that the detected contact force is converted into the position adjustment through the model,thereby changing the expected trajectory.The Simulink software of MATLAB is used to design the model.Finally,simulation analysis is used to verify the effectiveness of impedance control.