基于弹性装置驱动的外骨骼动力学研究

Research on exoskeleton dynamics driven by elastic device

基于被动式弹性助力原理,设计了一款外骨骼装置。首先,根据人体步态特点,讨论了目前外骨骼设计原理以及助力性能,发现现有被动式外骨骼助力效果并不显著,在此基础上提出了以多级能量锁止机构控制,重力势能与动能双效储能相结合的助力原理,依据该原理设计了外骨骼装置,并建立了外骨骼动力学模型。其次,利用外骨骼动力学模型对人体释能和储能阶段的髋关节转矩与髋关节做功进行了研究,得出该外骨骼在释能阶段能有效降低髋关节做功值且在储能阶段能有效降低人体关节冲击转矩值的结论。最后,以髋关节处杆长以及弹簧刚度作为变量对外骨骼进行了动力学性能优化,结果显示人体髋关节的做功值下降了33.42%。

Based on the principle of passive elastic assistance,an exoskeleton device was designed.Firstly,according to the characteristics of human gait,the existing exoskeleton design principle and assist performance were discussed and it showed that the assist effect of existing passive exoskeleton was inapparent.On this basis,an assist principle controlled by a multi-level energy locking mechanism using double-effect of gravity potential energy and kinetic energy was proposed.According to this principle,the exoskeleton device was designed and the dynamic model of the exoskeleton was established.Secondly,the dynamic model was used to study the human hip joint torque and work value in the stage of energy release and energy storage,and the conclusion was drawn that the exoskeleton could effectively reduce the work value of the hip joint in the stage of energy release,and could also effectively reduce the human joint impact torque value in the stage of energy storage.Finally,the dynamic performance of exoskeleton was optimized with the variables of rod length and spring stiffness.The result showed that the work value of human hip joint decreased by 33.42%.