Structural Design And Simulation Research Of Riding Lower Limb Walke

With the aggravation of aging in China,the society needs to invest a lot of manpower and material resources to solve the problems of walking fatigue of the elderly.As an auxiliary device,the lower limb exoskeleton has been gradually expanded and applied to the field of helping the elderly and the disabled,which has important practical significance for helping the elderly to walk.In this thesis,a riding lower limb walker is designed to reduce the burden of walking and standing of the elderly with walking disorders,improve the quality of life of the elderly,and make a theoretical basis for the development of the physical prototype.On the basis of consulting relevant patents and literatures in the field of lower limb exoskeleton walkers at home and abroad,this thesis compares and summarizes the exoskeleton research of different technical systems.In view of the common problems such as the complex structure of the existing walkers and the large number of driving motors,a lighter riding lower limb walker is designed by using the push-up active assist technology.The walker is driven by two motors.At the same time,the structure design of the inner side of the legs and the single point linkage can not only provide the user with upward lifting force,but also ensure the stability of the user’s walking.The main research contents of this thesis are as follows:(1)In order to meet the needs of the structure of the walker to adapt to the walking characteristics of the human body,this thesis studies the structure and motion characteristics of the lower limbs of the human body,and analyzes the gait and walking time-space parameters of the human body.The human walking simulation software is used to simulate and obtain the angle curve of each joint of the lower limbs as the basis for the design of the walker.(2)The force involved in the walking of the lower limbs of the human body is analyzed,and the scheme of reducing the burden is determined.The structure model of the walker is established.The structure of the walker includes:riding seat,slide rail,leg structure,ankle joint and foot.The strength analysis of the leg components of the single leg support walker is carried out,and the transmission,drive and control units are designed.(3)The kinematics mathematical modeling of the walker model is carried out by using the D-H method and the analytic geometry method,and the pose change of the walker is further described by using the matrix relationship.The kinematics simulation of the human-machine coupling model is carried out by using the simulation software.The human body is set as the power output to drive the walking aid movement,and the joint angle parameters of the walking aid are obtained.The human-machine motion synergy of the walking aid is analyzed by the simulation results.(4)The dynamic modeling of the walker is carried out by Lagrange’s second type equation,and the walking simulation of the walker model under load condition is carried out to obtain the torque of each joint,and the actual driving torque of the walker is calculated according to the simulation results.In order to evaluate the assist effect,the walking simulation of human lower limb model and human-machine coupling model is carried out respectively,and the assist effect is evaluated by comparing the torque of human knee joint.The riding lower limb walker studied in this thesis is designed from the analysis of human body load reduction scheme.The walker system is further evaluated and improved by establishing mathematical model and software simulation.The above research shows that the walker walks smoothly and has fine human-machine coordination.The evaluation of the assist effect shows that the walker can meet the expected assist requirements and meet the needs of the elderly to walk.