The Design And Research Of Hip Joint Assisted Exoskeleton

Many people have to spend a lot of time walking or walk a long distance in their daily work and life, such as, nurses, sanitation workers, hikers and soldiers, walking too much often leads to physical discomfort and muscle fatigue, which will affect their work efficiency and life quality. Long-term muscle fatigue is the main cause of muscle tissue damage, and its damage to human body is irreparable. At present, clinical research on muscle tissue damage is insufficient. As a result, many treatment methods for muscle tissue damage were created, but none of them are proved to be effective. Therefore, in order to provide better protection to the human body, and improve their work efficiency and life quality, it is very necessary to create a walking assist equipment, which is easy to wear, to assist human lower limb to walk normally.Exoskeleton is a new kind of human movement aided robot, walking assist exoskeleton can improve the movement ability of lower limb. Exoskeleton has been studied of a long time in the developed countries in Europe, United States and Japan, and achieved some results. China stared late on the research of exoskeleton. and the relevant technology is relatively lags behind at present, and mainly focused on rehabilitation exoskeleton. For this reason, this research project aims at develop a walking assist exoskeleton with following features:simple structure, easy to control.The development statue of exoskeleton is deeply analysis in this paper, and discussed their traits. Then, the walking assist exoskeleton’s numbers of DOF(degrees of freedom) is selected, as well as the exoskeleton’s drive system’s kind. The mechanical structure is designed by arranging the exoskeleton’s DOF, designing the man-machine junction part and the mechanical structure of drive system. According to the study results of human sports biomechanics, the drive system is designed to be a quasi-passive drive system. The stimulation is conducted with ADAMS after the mechanical structure of exoskeleton is designed, to prove the function of the quasi-passive drive system.A stage-divided control strategy is proposed according to the traits of the quasi-passive drive system, during the late stand phase, early swing phase and the transition phase, the exoskeleton is controlled by SAC(Sensitivity amplify control) to follow human lower limb, during the early stand phase and the late swing phase, the exoskeleton is controlled by output torque control scheme to help people walking. The TMS320F2812 is selected to be the exoskeleton’s CPU to meet real-time requirement and the variety of senor signal, the hardware circuit of the minimum system of DSP is designed, as well as the bipolar type H bridge driving circuit.At last, the exoskeleton’s experimental platform is built up, the validity of SAC controller and output torque control scheme are proved through experiments.