Design And Performance Test Of A New Kenn Joint Exoskeleton

With the development of science and technology,more and more intelligent equipment has entered people’s life.As a wearable exoskeleton robot which has direct interaction with human body,it has a broad development prospect.In military and industrial fields,it can significantly enhance the wearer’s load-bearing capacity and reduce human metabolic consumption.In the medical field,exoskeleton can effectively replace the shortage of rehabilitation trainers,and provide good exercise rehabilitation training for wearers and exercise assistance for people with motor disability.Based on the practical significance of assisting lower limb movement ability loss and assisting load bearing capacity enhancement,this topic carries out the design and research of knee limb exoskeleton robot with simple and flexible structure,comfortable wearing and strong supporting performance as the design objectives.After in-depth discussion on the development history and key technologies of lower limb exoskeleton robot at home and abroad,this paper will study the design of knee limb exoskeleton from four aspects:Based on the study of the physiological structure and musculoskeletal movement forms of human lower limbs,combined with the clinical gait data of human lower limbs,the configuration of the new knee exoskeleton was studied,the freedom configuration satisfying the stable walking function was selected,the exoskeleton prototype model was established by using three-dimensional software,and the force analysis of the single-leg standing posture was carried out by using finite element software.The results indicate that the design of lower limb exoskeleton robots can effectively reduce the force on the knee joint.Based on D-H parameter coordinate method and differential transformation method,forward kinematics analysis of exoskeleton was carried out,and then the kinematics model was verified by Robtic toolbox in Matlab software.Then,according to the clinical gait data,the gait curves of the three joints of the wearer’s lower limbs were fitted,and the kinematic model of the new knee joint was established by Lagrange method.Through the kinematic model,the relationship among the pose,speed and torque of each connecting rod was revealed.Simultaneously providing comparative data for Adams simulation.By using Adams software,through dynamic simulation and analysis,we obtained the displacement,angular velocity and torque variation trend of each joint of the lower limb exoskeleton and the displacement and velocity curve of the midpoint of the foot,and verified the reliability of the simulation design.The force transfer mathematical model of the new knee exoskeleton was established,and the relationship between the torque at the knee joint of the lower limb exoskeleton and each component was obtained.The torque change of the lower limb exoskeleton with the motion Angle of the knee joint was obtained by Matlab software.Finally,the length of the knee joint bar was optimized by genetic algorithm.The optimization results indicate that the optimized rod can provide greater output torque.