Design And Research Of Variable Stiffness Knee Exoskeleton System Without Dynamic

With the continuous development of the aging population in our country and the continuous increase in the obesity rate of residents,the incidence of knee joint diseases has gradually increased,which has brought great inconvenience and pain to patients.One of the factors that induce knee joint diseases is Constant overstress of the knee joint.The exoskeleton of the lower limbs can effectively reduce the force on the knee joint,and supplemented by drug therapy can achieve the purpose of preventing and treating knee joint diseases.Aiming at the motion law of the instantaneous center of the human knee joint rotation,and the characteristics of the exoskeleton providing high auxiliary weight-bearing rigidity during the support phase motion of the lower limbs,and the compatibility of the exoskeleton and the knee joint motion space in the swing phase,a system is designed.Non-dynamic variable stiffness knee exoskeleton.The main research contents are as follows:First of all,based on the analysis of the movement mechanism of the lower limbs of the human body,this paper proposes a system design scheme for the non-dynamic variable stiffness knee exoskeleton to achieve the purpose of high stiffness in the support phase of the human-machine system and low stiffness in the swing phase,which mainly includes variable The structure design of the rigid exoskeleton knee joint part and the thigh intelligent tensioning physical interaction device.Secondly,design and verify the coupling performance of man-machine wear.Apply the mobility recursive restriction condition and static determinate recursive restriction condition,and meet the two mobility boundary conditions,carry out the statically determinate structure design of the man-machine system,so that the designed knee joint exoskeleton can be realized without external load The effect of no internal force.The exoskeleton with the human hip joint as the origin of the global coordinate system and the human lower limb kinematics models were established respectively,and the reachable motion space of the exoskeleton ankle joint and the motion trajectory of the human ankle joint were drawn.Movement coordination requirements.Finally,the auxiliary bearing performance of the knee exoskeleton is analyzed and optimized.A dynamic model of the knee joint rotation part of the knee exoskeleton is established,and MATLAB is used to solve the driving force required by the knee exoskeleton during the human gait support phase movement by using a numerical iterative algorithm.The elastic coefficient of the spring in the spring group of the variable stiffness mechanism is optimized so that the knee joint exoskeleton can achieve a better auxiliary bearing effect in the support phase.