下肢外骨骼变轴线膝关节构型设计与杆长优化  

Design and Optimization of Lower Limb Exoskeleton with Variable Axis Knee Joint Mechanism

作　　者：李潇 张建军[1] 戚开诚[1] 杨高炜[1] Li Xiao;Zhang Jianjun;Qi Kaicheng;Yang Gaowei(School of Mechanical Engineering,Hebei University of Technology,Tianjin 300130,China)

机构地区：[1]河北工业大学机械工程学院,天津300130

出　　处：《机械科学与技术》2020年第8期1230-1236,共7页Mechanical Science and Technology for Aerospace Engineering

基　　金：国家自然科学基金项目(51175144);天津市自然科学重点基金项目(17JCZDJC40200);河北省教育厅科学研究计划重点项目(ZD2019052)资助。

摘　　要：针对人体膝关节轴线具有可变性,定轴线膝关节机构必然使外骨骼与人腿协调性较差的问题,在一种无驱动含耦合双支闭链的下肢外骨骼的基础上,采用一种变轴线膝关节机构。首先,根据人体膝关节“J”型瞬心轨迹特点,确定合适的变轴线膝关节机构,并且建立含变轴线膝关节的外骨骼整体模型;其次,通过遗传算法计算出符合人体膝关节瞬心轨迹的变轴线膝关节的参数;最后,通过MATLAB计算验证变轴线膝关节的瞬心轨迹符合人体膝关节瞬心轨迹。结果表明:变轴线膝关节瞬心轨迹更加贴合人体膝关节的瞬心轨迹,含变轴线膝关节机构的外骨骼步态更加符合人体步态。Aiming at the problem that variability of the human knee joint axis and the fixed-axis knee joint mechanism must make the exoskeleton and the human leg have a poor coordination.Based on an unpowered lower limb exoskeleton with a coupled double-branched chain,a variable-axis knee joint mechanism was adopted.Firstly,according to the characteristics of the human knee joint′J′type instantaneous trajectory,the appropriate variable axis knee joint mechanism was determined,and the overall model of the exoskeleton with the variable-axis knee joint was established.Secondly,the parameters of the variable-axis knee joint conforming to the instantaneous trajectory of the human knee joint were calculated by genetic algorithm.Finally,the MATLAB calculation verified that the instantaneous trajectory of the variable-axis knee joint conforms to the instantaneous trajectory of the human knee joint.The results show that the instantaneous trajectory of the variable knee joint is more suitable for the instantaneous trajectory of the human knee joint,and the exoskeleton gait with the variable axis knee joint mechanism is more consistent with the human gait.

关 键 词：无驱动下肢外骨骼 变轴线膝关节 机构设计 遗传算法 MATLAB 

分 类 号：TH112[机械工程—机械设计及理论]