Research On The Mechanism And Technology Of Lower Extremity Exoskeleton Assist

Since the 21st century,developed countries have carried out the research of lower limb exoskeleton.The research has military and social significance,especially in the aging society of China.Therefore,this paper takes the lower limb exoskeleton system as object,and related mechanism and technology are researched.This article first analyzes the joint angle and ground generalized force during the cycle of the level waling gait.And with the aid of Opensim software,muscle activation degree of specific lower limb surface muscle is attained.Then predicting the motion trend of lower limb joint based on the probabilistic neural network,it reveals that the accuracy rate reaches above 80%.Then structure design of the exoskeleton is finished,by allocating degrees of freedom,determining the form of system drive,arranging the certain sensors.The whole structure design matches for various users.Based on the Adams-Matlab associated simulation and human-machine interaction model,the general lower limb exoskeleton of swinging leg model is simulated.Two control strategies are torque amplifying control and sensitivity amplifying combined by neural network.After effect assessment and the practical conditions comes to the conclusion that the latter is more practical.Finally combined with lower limb exoskeleton worn experiment advancing the hypothesis that the lower limb joint angle changes smooth during human body normal level walking gait in the sagittal plane.Drawing lessons from the definition of surface roughness and the introduction of Gaussian filter,the lower limb exoskeleton man-machine coupling roughness parameter definitions and calculation methods are set up.And according to the method,quantitative calculation and evaluation on three gaits of certain lower limb exoskeleton has been concluded,which suggests the man-machine efficacy.This evaluation method can be used as general lower limb exoskeleton evaluation index.Domestic studies on lower limb exoskeleton have overtaken the preliminary stage,so in this paper,the basic research on lower limb exoskeleton provides foundation and reference basis for structure design,control strategies and man-machine efficacy evaluation.