发表机构
Karlsruhe Institute of Technology; University of Waterloo（卡尔斯鲁厄理工学院; 滑铁卢大学）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本研究通过纵向案例，提出两种新角动量度量分析空手道回旋踢，发现不稳定踢击的角动量峰值特征，可为动态运动稳定性分析提供参考。
AI 中文摘要
现实世界中的人类步态不仅限于直线行走，某些情境甚至需要剧烈的来回旋转。平稳且稳定的执行看似直观，但其背后的力学机制仍属未知。空手道回旋踢可能是展现动态来回旋转的极端案例，但研究角动量（AM）管理可能为动态人体运动中的稳定性分析以及机器人和外骨骼中更平滑的步态提供信息。本文引入了两种新的基于角动量的度量，并分析了与角动量相关的变量，以研究无目标的可收回后腿空手道回旋踢。其目的是理解潜在的角动量管理，分析稳定与不稳定踢击之间的差异，并探究这些变量和度量如何随着进步随时间变化。进行了一项为期一年的纵向研究，第一作者作为空手道学员参与，同时招募了一名空手道教练参与一次课程作为专家，其数据用于比较。结果表明，不稳定的踢击在击打前具有更高的总角动量峰值，而在击打后具有更小的制动峰值。所提出的基于角动量的度量能够识别某些不稳定踢击的原因，但由于踢击可能因不同原因而不稳定，因此无法在稳定与不稳定踢击之间做出明确区分。尽管如此，所提出的度量可作为性能指标应用于分析其他类型的动态运动。然而，要将它们作为稳定性标准，建议还需考虑它们与时间、运动学和压力中心的协调。
英文摘要
Human gait in reality extends beyond straight-line walking, with some situations even requiring drastic back-and-forth rotations. A smooth and stable execution may seem intuitive, but the underlying mechanics remains unknown. The Karate roundhouse kick may be an extreme case of exhibiting dynamic back-and-forth rotations, but investigating the angular momentum (AM) management can potentially inform stability analysis in dynamic human motions and smoother gait in robots and exoskeletons. This paper introduces two new AM-based measures and analyzes AM-related variables to study the target-less retractable back-leg Karate roundhouse kick. The purpose is to understand the underlying AM management, analyze the differences between stable and unstable kicks, and investigate how these variables and measures change over time with improvement. A one-year longitudinal study was conducted with the first author as a Karate student, and a Karate instructor was also recruited for one session as an expert, whose data is used for comparison. Results show that unstable kicks have higher peak total AM before Strike and smaller braking peak after Strike. The proposed AM-based measures are able to identify the cause of some unstable kicks, though no clear distinction could be made between stable and unstable kicks since kicks can be unstable for different reasons. Nonetheless, the proposed measures can be applied as performance measures to analyze other types of dynamic motions. To incorporate them as stability criteria, however, it is recommended to also consider their coordination with time, kinematics, and center of pressure.
