Design And Analysis Of Limb Rehabilitation Robot On Bed

At present,rehabilitation robots which can effectively improve the motor function of patients are gradually accepted by the public.Rehabilitation robot training system can not only provide safe and effective limb movement training for bedridden patients,but also improve the cardiopulmonary function of patients,reduce muscle atrophy and avoid many complications caused by long-term bedridden.At the same time,the earlier functional training for stroke patients,the more can reduce the sequelae,reduce the disability rate,and make the patients return to society.Therefore,this paper proposes a kind of rehabilitation training robot for early patients.Firstly,the physiological structure,movement characteristics and movement space of human body are analyzed.Based on the above analysis,the degree of freedom of human limbs is simplified,and the range of motion of human joints is determined by considering the application scene and object of the rehabilitation robot.According to the above analysis results,the overall structure design of the rehabilitation robot and the design of the multi position conversion bed are carried out.Secondly,the kinematics of the designed upper limb rehabilitation module is analyzed,and the forward kinematics solution of the upper limb rehabilitation module is obtained.Based on the actual motion range of the robot,the workspace of the upper limb rehabilitation robot is solved by Monte Carlo method.Based on the trajectory of the upper limb rehabilitation robot,the driving force of the motor needed to drive the patient’s upper limb for rehabilitation training is calculated by software.In order to protect the safety of rehabilitation training,a safety protection mechanism based on Jacobian matrix is established.Thirdly,the mechanism of the designed lower limb rehabilitation module is analyzed,and the man-machine system model of the lower limb rehabilitation module is established.In order to ensure the comfort of patients in the process of rehabilitation training and avoid the impact of speed mutation on patients,the quintic polynomial trajectory is planned.The dynamic model of lower limb rehabilitation module is established,and based on the dynamic model,the motor driving force needed to drive patients’ lower limbs for rehabilitation training is calculated.Finally,the control system of rehabilitation robot is designed.Firstly,based on PID principle and Jacobian matrix of force,a passive training control system with joint torque safety protection function is designed.Then,in order to reconstruct the motion sense of the patients and provide the patients with real experience of stepping on the sand,an active training control strategy based on the pressure bearing characteristics of the sand is designed.The control strategy can control the robot to simulate the soft and hard sand environment,and improve the authenticity of rehabilitation training simulation.