Structural Design And Simulation Of Lower Limb Hydrotherapy Rehabilitation Robot Based On Exoskeleton

In recent years,the number of patients with limited lower limb walking function caused by stroke in China has been increasing,and gradually showing a trend of younger age.Aiming at the needs of lower limb walking rehabilitation of stroke patients in late stage,this paper combined with the popular hydrotherapy technology in the field of rehabilitation medicine.We designed a wheelchair exoskeleton robot for water walking training.The main research work and results includes:（1）Aiming at the structural characteristics,motion characteristics and walking gait of human lower limbs,combined with CGA gait data collected in the laboratory.I analyzed the angle,torque and power data of lower limb joints,and used these data as the basis for the design and selection of drive components and transmission components.Comparing the positive effect of hydrotherapy on rehabilitation of stroke patients with traditional land training,the feasibility of combining hydrotherapy with exoskeleton was analyzed.（2）According to the needs of patients using equipment for underwater walking rehabilitation training process.The structural design requirements of the lower limb spa rehabilitation robot in the aspects of freedom,universality and safety of the lower limb exoskeleton are proposed.The structural design requirements of the lower limb hydrotherapy rehabilitation robot in the aspects of freedom,universality and safety of the lower limb exoskeleton are proposed.According to this requirement,the mechanical scheme design was completed,including the range of joint motion,the size of each part of the lower limb exoskeleton,the design and selection of the drive system and the scheme of the whole machine.Through the use of CREO software for the structural design modeling of the components of the lower limb hydrotherapy rehabilitation robot,including the frame,the lower limb exoskeleton component,the connecting rod transmission component,the brace component,the motor-reducer component and other mechanisms,the assembly of the components,complete the overall structure design of the lower limb hydrotherapy rehabilitation robot.（3）Aiming at the kinematics and dynamics of lower limb hydrotherapy rehabilitation robot.Based on D-H parameter method,forward and inverse kinematics of lower limb exoskeleton components of lower limb spa rehabilitation robot were solved.The relationship between the joint Angle and the coordinate position of the lower extremities were obtained.Lagrange method was used to solve the inverse dynamics of lower limb exoskeleton,and the dynamics equations of each joint of lower limb exoskeleton were obtained.The kinematics simulation and optimization of the two-dimensional simplified model of the lower extremity spa rehabilitation robot was carried out in ADAMS,which improved the fitting degree of the motion Angle of the lower extremity exoskeleton and the motion Angle of the CGA joint,and obtained the optimal size of the connecting rod transmission component.Driven by CGA gait joint torque,the torque variation curve at the output shaft center of the motor-reducer assembly was obtained through dynamics simulation,and the rationality of the drive system selection was preliminarily verified.（4）Aiming at different working conditions of lower limb spa rehabilitation robot.ANSYS is used to analyze the load capacity of the equipment.By using FLUENT dynamic grid technology,the dynamic pressure distribution and the torque generated by flow resistance on the lower limb joints of the two-dimensional simplified model of the lower limb hydrotherapy rehabilitation robot during the walking process are simulated.The influence of water flow resistance on the output torque of the driving system of the lower limb hydrotherapy rehabilitation robot was simulated in ADAMS.It is verified that the designed lower limb spa rehabilitation robot can meet the use requirements.