The Research On Power And Energy Driving Of Man-machine System Exoskeleton

The research of power-assisted lower extremity exoskeleton is based on the demand of military,medical and earthquake.Its aim is to improve the combat capability of individual soldiers with the help of it.Through the combination of exoskeleton and doctor,it is possible for disabled people to walk.With the help of the power-assisted lower extremity exoskeleton,it can improve the efficiency of rescue,so we can save more lives in the golden rescue time.The third generation exoskeleton test model of Southwest Jiaotong University was analyzed.The energy of weight walking in man-machine system is analyzed from the process of human walking.The detailed analysis is as follows.(1)To research the gait of the weight walking process,the parameters were clearly defined,and the two supporting states of body weight walking were divided.Using the optical acquisition system to collect the spatial coordinates of the key points of the body weight walking process,to simplify the human walking model and get the ball stick model.The space trajectory of load bearing was researched,and decomposed it into vertical and horizontal motion.Using different basic function to fit,so the mathematical model of different load and walking speed was obtained.To analyze the space coordinate point of human body,the joint angle of lower extremity at every test moment was obtained.Using the SineSqr basic function to fit,and the rationality of the fitting result was analyzed.(2)The third generation exoskeleton test model of Southwest Jiaotong University was researched,which was treated as a 5-link model.Based on the differential equation of rigid body plane motion,the dynamic model of each joint Angle in two different parts was founded.To analyze weight walking process of human body,it is believed that the body at two legs' support state when the load is at its lowest point in a certain period.To solve the minimum value of the fitting vertical displacement curve,the corresponding time was obtained,so the time of the whole cycle was obtained.The exoskeleton at different load and walking speed was simulation analyzed,and it was compared at the left leg support state,the left to right leg support state and full period.(3)Based on the kinematics parameters of human weight-bearing walking,mechanical energy of exoskeleton,load and system was analyzed,and energy models were obtained.To calculate 8 working conditions in preceding part of the text,the energy of different load and walking speed was compared.(4)Adopting the method of sectional study to improve the method of calculating the work of objects,the work in each stage was obtained,which is energy consumption.And the energy consumption was compared at different load and walking speed.To analyze the knee joint structure of exoskeleton,the distance parameter between the hydraulic cylinder and the exoskeleton was obtained.The driving force of supporting leg's knee joint hydraulic cylinder was researched.From the above,the kinematics,dynamics and energy analysis of the weight-bearing walking process of man-machine system lay the foundation for the design of exoskeleton energy,driving system and the structure.