Design and analysis of a novel 12-DOF self-balancing lower extremity exoskeleton for walking assistance
Design and analysis of a novel 12-DOF self-balancing lower extremity exoskeleton for walking assistance
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DOI：
10.1016/j.mechmachtheory.2021.104519
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发表时间：
2021-08-20
影响因子：
5.2
通讯作者：
Wu, Xinyu
中科院分区：
文献类型：
--
作者：
Liu, Jingshuai;He, Yong;Wu, Xinyu
下肢外骨骼常用作瘫痪患者的步行辅助康复机器人。然而，由于需要拐杖或其它装置来维持平衡，欠致动外骨骼具有有限的适用性。本文旨在设计一种结构符合人体解剖结构、具有12自由度全驱动的新型自平衡下肢外骨骼机构。基于以人为本的设计原则，提出了一种仿生外骨骼机构综合方法。基于3自由度RCM髋关节机构、1自由度平行四边形连杆膝关节机构和2自由度解耦并联踝关节机构，设计了一种新型串并联混合机构。为了描述该机构的运动学正解和逆解，分别用D-H法和几何法求出了机构的封闭解。此外，为了分析外骨骼的工作空间，建立了双足支撑和单足支撑阶段的可达工作空间方程。数值仿真和实验结果验证了运动学模型的正确性和自平衡行走能力，说明了所提出的外骨骼机构的可行性。
Lower extremity exoskeletons are often used as walking assistance rehabilitation robots for paralyzed patients. However, due to the requirement of crutches or other devices to maintain balance, the under-actuated exoskeleton has limited applicability. This paper aims to design a novel mechanism for the self-balancing lower extremity exoskeleton, which structurally consistent with the human anatomy and fully actuated with 12 DOFs. In this study, based on the humancentered design principles, a bio-inspired exoskeleton mechanism synthesis methodology is presented. The novel serial-parallel hybrid mechanism is designed based on a 3-DOF RCM hip mechanism, 1-DOF parallelogram-linkage knee mechanism, and 2-DOF decoupled parallel ankle mechanism. To describe the forward and inverse kinematics of the mechanism, the closed-form solutions by the D-H method and geometric method are obtained, respectively. In addition, to analyze the exoskeleton workspace, the reachable workspace equations in the double foot support and single foot support phases are established. The numerical simulation and experimental results show the kinematics model validity and self-balancing walking ability, which illustrate the feasibility of the proposed exoskeleton mechanism.