中文摘要：

液压驱动下肢助力外骨骼是一种典型的人机交互类机器人,在跟随人体行进的同时,可提高人的负重能力。为实现最优化的结构设计以降低对系统压强、液压缸尺寸的要求,通过仿生学分析人类正常步行时的步态数据,依据准拟人化设计准则,采用CAD设计软件、数值计算等方法,给出了液压驱动膝关节的设计过程,并通过MATLAB等仿真软件进行了验证。基于确定的模型参数,进行了结构设计及平台搭建,并进行了穿戴试验。仿真及试验结果表明,该方法设计的外骨骼膝关节可以满足步行及负重需求。在负重由10增加为20 kg时,即负重增加一倍时,膝关节的轨迹平均跟踪误差减小了0.05%,跟踪误差最大值增加了20.7%,但是相对于整个膝关节的活动范围,该误差仅占总活动范围的1.2%。该研究为优化液压驱动下肢助力外骨骼提供了参考方法,并可为直线执行器驱动外骨骼其他关节的优化设计提供参考。

英文摘要：

As a kind of typical human-machine interaction robot,the powered lower-limb exoskeleton driven by hydraulics can augment wearer’s power while following wearer.This kind of exoskeleton has a broad application in military field,rescue occasions,and so on,however,there are still many technical difficulties which need to be studied,such as structure optimization.There are 3 kinds of design concepts among the exoskeleton structure design.To guarantee the flexibility and decrease the dead weight of exoskeleton,quasi-anthropomorphic design was adopted,which means the lower-limb exoskeleton is similar to leg but does not need one-to-one match.According to quasi-anthropomorphic design rule,7 degrees of freedom for single leg were set to satisfy the freedom need of wearer.Among these 7 degrees of freedom,only 2 degrees are active which are located in sagittal plane of knee joint and hip joint.During designing the active freedom of knee joint,the core parameters are the size of hydraulic cylinder and the torque which can be produced.So it is significant to study a method which can lead to a minor size of hydraulic cylinder while producing the same torque.To optimize the structure of knee joint and its hydraulic system,the computer aided design（CAD）method and the numerical calculation method were adopted to design the structure of the hydraulic cylinder and its installation position.According to the schematic diagram of structure,the relationship of torque,arm of force,and installation position was built.Design indicators were obtained through analyzing the clinical gait analysis（CGA）data,which was widely used in lower-limb exoskeleton research.To find out the optimized parameter,MATLAB was used to present graphics which depicted the nonlinear relationship which was built before.According to the optimization method,the hydraulic driven knee joint of the lower limb exoskeleton was designed and assembled.During the normal walking phase,there are 2 kinds of torques in knee joint,which contain flexure torque and extens