On The Control And Simulation Of The Wearable Rehabilitative Leg

The research into the wearable rehabilitative leg has very important theoretical andpractical value, which has aroused the widespread concern among the scholars around theworld. At present, the theoretical and practical research of the rehabilitative leg has achievedsome significant accomplishments, but it is still far from what is expected by people. Themain reason is high energy consumption, lower efficiency and considerable expense, whichare not suitable for wide usage. The mechanical structure with underactuated joints based onthe bionic laws needs to be developed to increase the efficiency and comfort of the user. Thebionic walking mechanism, mechanical design, analysis of the motion simulation andcontrol strategy are researched in this paper. The main content is as follows:Firstly, the structure of the lower extremity is analyzed in terms of the bionics. Theangle and comfort range of the assistive leg are obtained. Then the3D (3dimensional)structure is developed by software Solidworks. And every part of the wearable leg isillustrated. It can be found that the design in this paper conform to the physiologicalstructure of normal human being. The comfort and security are taken into accountsubstantially.Secondly, a brief analysis and presentation on the coupled motion in human-machinesystem is given in different motion pattern. Then the dynamic model of human andrehabilitative leg is analyzed. The machine motion pattern is mainly researched under thecondition of the early rehabilitation or being badly wounded in the lower extremity. Themost commonly used simulation software Adams is selected to run dynamic simulation. InSolidworks, the standard human and rehabilitative leg models are assembled and introducedinto Adams. By simulation, the relation of the force and angle of the joint can be intuitivelydetected.Finally, the nonlinear control strategy of human-machine system is applied under thismachine motion pattern. In this pattern, the rehabilitative leg needs to follow the ankle of human being. Because of the high nonlinearity in this system, it is necessary to applylinearization feedback and sliding mode nonlinear control strategies to track the ankle ofhuman for the rehabilitative leg. This kind of control, which conforms to the law of humanmotion, gives us a better understanding of bionics of the human-machine motion.