Yamada Takumi, Aoi Shinya, Adachi Mau, Kamimura Tomoya, Higurashi Yasuo, Wada Naomi, Tsuchiya Kazuo, Matsuno Fumitoshi
Department of Mechanical Engineering and Science, Graduate School of Engineering, Kyoto University, Kyoto, Japan.
Department of Aeronautics and Astronautics, Graduate School of Engineering, Kyoto University, Kyoto, Japan.
Front Bioeng Biotechnol. 2022 Feb 28;10:825157. doi: 10.3389/fbioe.2022.825157. eCollection 2022.
Horses use the transverse gallop in high-speed running. However, different animals use different gaits, and the gait preference of horses remains largely unclear. Horses have fore-aft asymmetry in their body structure and their center of mass (CoM) is anteriorly located far from the center of the body. Since such a CoM offset affects the running dynamics, we hypothesize that the CoM offset of horses is important in gait selection. In order to verify our hypothesis and clarify the gait selection mechanisms by horses from a dynamic viewpoint, we developed a simple model with CoM offset and investigated its effects on running. Specifically, we numerically obtained periodic solutions and classified these solutions into six types of gaits, including the transverse gallop, based on the footfall pattern. Our results show that the transverse gallop is optimal when the CoM offset is located at the position estimated in horses. Our findings provide useful insight into the gait selection mechanisms in high-speed running of horses.
马在高速奔跑时采用横向疾驰步态。然而，不同动物使用不同的步态，而马的步态偏好仍在很大程度上不清楚。马的身体结构存在前后不对称，其质心（CoM）位于身体前方远离身体中心的位置。由于这种质心偏移会影响奔跑动力学，我们推测马的质心偏移在步态选择中很重要。为了验证我们的假设并从动力学角度阐明马的步态选择机制，我们开发了一个具有质心偏移的简单模型，并研究了其对奔跑的影响。具体而言，我们通过数值方法获得了周期解，并根据脚步模式将这些解分为六种步态类型，包括横向疾驰步态。我们的结果表明，当质心偏移位于在马身上估计的位置时，横向疾驰步态是最优的。我们的研究结果为马高速奔跑时的步态选择机制提供了有用的见解。
