Department of Mechanical Engineering, University of Waterloo, 200 University Avenue West, Waterloo, ON, N2L 3G1, Canada.
Ann Biomed Eng. 2021 Jul;49(7):1645-1656. doi: 10.1007/s10439-021-02783-2. Epub 2021 May 3.
Active neck musculature plays an important role in the response of the head and neck during impact and can affect the risk of injury. Finite element Human Body Models (HBM) have been proposed with open and closed-loop controllers for activation of muscle forces; however, controllers are often calibrated to specific experimental loading cases, without considering the intrinsic role of physiologic muscle reflex mechanisms under different loading conditions. This study aimed to develop a single closed-loop controller for neck muscle activation in a contemporary male HBM based on known reflex mechanisms and assess how this approach compared to current open-loop controllers across a range of impact directions and severities. Controller parameters were optimized using volunteer data and independently assessed across twelve impact conditions. The kinematics from the closed-loop controller simulations showed good average CORA rating to the experimental data (0.699) for the impacts following the ISO/TR9790 standard. Compared to previously optimized open-loop activation strategy, the average difference was less than 9%. The incorporation of the reflex mechanisms using a closed-loop controller can provide robust performance for a range of impact directions and severities, which is critical to improving HBM response under a larger spectrum of automotive impact simulations.
主动颈部肌肉在头部和颈部受到冲击时的反应中起着重要作用，并且可能会影响受伤的风险。已经提出了具有开环和闭环控制器的有限元人体模型（HBM）以激活肌肉力；然而，控制器通常针对特定的实验加载情况进行校准，而不考虑在不同加载条件下生理肌肉反射机制的内在作用。本研究旨在为基于已知反射机制的当代男性 HBM 开发一种用于颈部肌肉激活的单一闭环控制器，并评估该方法与当前开环控制器在各种冲击方向和严重程度下的比较。使用志愿者数据对控制器参数进行了优化，并在 12 种冲击条件下进行了独立评估。闭环控制器模拟的运动学表现出与实验数据（0.699）的良好平均 CORA 评分（根据 ISO/TR9790 标准），适用于后续的冲击情况。与之前优化的开环激活策略相比，平均差异小于 9%。使用闭环控制器结合反射机制可以为各种冲击方向和严重程度提供稳健的性能，这对于在更大范围的汽车冲击模拟下改善 HBM 响应至关重要。
