Department of Mechanical Engineering, University of Michigan, Ann Arbor, MI, USA.
Department of Mechanical Engineering, University of Michigan, Ann Arbor, MI, USA.
J Biomech. 2019 Feb 14;84:121-128. doi: 10.1016/j.jbiomech.2018.12.030. Epub 2018 Dec 23.
Human crawling performance and technique are of broad interest to roboticists, biomechanists, and military personnel. This study explores the variables that define crawling performance in the context of an outdoor obstacle course used by military organizations worldwide to evaluate the effects of load and personal equipment on warfighter performance. Crawling kinematics, measured from four body-worn inertial measurement units (IMUs) attached to the upper arms and thighs, are recorded for thirty-three participants. The IMU data is distilled to four metrics of crawling performance; namely, crawl speed, crawl stride time, ipsilateral limb coordination, and contralateral limb coordination. We hypothesize that higher performance (as identified by higher crawl speeds) is associated with more coordinated limbs and lower stride times. A cluster analysis groups participants into high and low performers exhibiting statistically significant differences across the four performance metrics. In particular, high performers exhibit superior limb coordination associated with a "diagonal gait" in which contralateral limbs move largely in-phase to produce faster crawl speeds and shorter crawl stride times. In contrast, low performers crawl at slower speeds with longer crawl stride times and less limb coordination. Beyond these conclusions, a major contribution of this study is a method for deploying wearable IMUs to study crawling in contextually relevant (i.e. non-laboratory) environments.
人类爬行性能和技术引起了机器人专家、生物力学专家和军事人员的广泛关注。本研究探讨了在全球军事组织用于评估负载和个人装备对作战人员性能影响的户外障碍课程背景下定义爬行性能的变量。从附着在上臂和大腿上的四个穿戴式惯性测量单元 (IMU) 测量爬行运动学，记录了三十三名参与者的数据。IMU 数据被提炼为四个爬行性能指标；即爬行速度、爬行步幅时间、同侧肢体协调和对侧肢体协调。我们假设更高的性能（以更高的爬行速度为标志）与更协调的肢体和更低的步幅时间有关。聚类分析将参与者分为表现较好（通过较高的爬行速度来识别）和表现较差的两组，两组在四个性能指标上存在显著差异。特别是，表现较好的组表现出更好的肢体协调，表现出“对角线步态”，即对侧肢体基本同步运动，从而产生更快的爬行速度和更短的爬行步幅时间。相比之下，表现较差的组爬行速度较慢，爬行步幅时间较长，肢体协调程度较低。除了这些结论，本研究的一个主要贡献是一种使用可穿戴式 IMU 在相关（即非实验室）环境中研究爬行的方法。
