Shen Keli, Chemori Ahmed, Hayashibe Mitsuhiro
Neuro-Robotics Laboratory, Department of Robotics, Graduate School of Engineering, Tohoku University, Sendai, Japan.
LIRMM, University of Montpellier, CNRS, Montpellier, France.
Front Neurorobot. 2021 May 17;15:679570. doi: 10.3389/fnbot.2021.679570. eCollection 2021.
The study of human balance recovery strategies is important for human balance rehabilitation and humanoid robot balance control. To date, many efforts have been made to improve balance during quiet standing and walking motions. Arm usage (arm strategy) has been proposed to control the balance during walking motion in the literature. However, limited research exists on the contributions of the arm strategy for balance recovery during quiet standing along with ankle and hip strategy. Therefore, in this study, we built a simplified model with arms and proposed a controller based on nonlinear model predictive control to achieve human-like balance control. Three arm states of the model, namely, active arms, passive arms, and fixed arms, were considered to discuss the contributions of arm usage to human balance recovery during quiet standing. Furthermore, various indexes such as root mean square deviation of joint angles and recovery energy consumption were verified to reveal the mechanism behind arm strategy employment. In this study, we demonstrate to computationally reproduce human-like balance recovery with and without arm rotation during quiet standing while applying different magnitudes of perturbing forces on the upper body. In addition, the conducted human balance experiments are presented as supplementary information in this paper to demonstrate the concept on a typical example of arm strategy.
人体平衡恢复策略的研究对于人体平衡康复和仿人机器人平衡控制具有重要意义。迄今为止，人们已经做出了许多努力来改善安静站立和行走运动时的平衡。文献中提出了手臂使用（手臂策略）来控制行走运动中的平衡。然而，关于手臂策略在安静站立时与脚踝和髋部策略一起对平衡恢复的贡献的研究有限。因此，在本研究中，我们构建了一个带有手臂的简化模型，并提出了一种基于非线性模型预测控制的控制器，以实现类人平衡控制。考虑了模型的三种手臂状态，即主动手臂、被动手臂和固定手臂，以讨论手臂使用对安静站立时人体平衡恢复的贡献。此外，还验证了各种指标，如关节角度的均方根偏差和恢复能量消耗，以揭示采用手臂策略背后的机制。在本研究中，我们展示了在安静站立时，在对上半身施加不同大小扰动力的情况下，通过计算再现有无手臂旋转的类人平衡恢复。此外，本文还展示了所进行的人体平衡实验作为补充信息，以在一个典型的手臂策略示例中演示该概念。
