数据和差距特征对机动活动期间运动的非线性计算的影响
Arash Mohammadzadeh Gonabadi1, Thad W Buster1, Guilherme M Cesar2
1Rehabilitation Engineering Center, Institute for Rehabilitation Science and Engineering, Madonna Rehabilitation Hospitals, Lincoln, NE, USA.
Journal of applied biomechanics
|June 6, 2024
概括
人类动力学数据中的差距显著增加了Lyapunov指数 (LyE) 计算中的错误. 立方斜线插值可以减轻一些错误,但仔细报告数据差距和长度对于准确的运动变化分析至关重要.
科学领域:
- 生物力学 生物力学
- 动态系统分析 动态系统分析
- 人类运动中的数据科学
背景情况:
- 人类运动的可变性通常使用利亚普诺夫指数 (LyE) 来量化.
- LyE计算的准确性可能会受到数据质量的影响,包括数据序列长度和时间差距.
- 了解这些影响对于可靠的运动动态表征至关重要.
研究的目的:
- 调查数据序列长度和差距持续时间对莱普诺夫指数 (LyE) 计算准确性的影响.
- 为了比较这些因素的影响,有和没有立方脊柱插值.
- 为准确的人类运动变化性分析提供数据处理指南.
主要方法:
- 人类动力学数据被操纵,以创建不同的数据序列长度 (28%和100%的原始) 和间隙持续时间 (0.050.20秒).
- 对操纵的数据进行了立方线插值计算,并没有对操纵的数据进行立方线插值.
- 使用Lyapunov指数百分比误差 (%误差) 来量化准确性影响.
主要成果:
- 较长的间隙显著增加了所有平面的非互插数据中的 LyE% 误差.
- 立方斜线插值减少了LyE%的误差,前面平面数据中只有0.20s的差距显示出明显的误差增加.
- 数据序列长度没有显著影响非插入的LyE%误差,但较短的序列长度增加了插入时的斜边平面LyE%误差.
结论:
- 忽略数据缺口的插值可能会导致错误的高LyE值,错误地表示运动变化.
- 特定的条件,如长的正面平面间隙 (0.20秒) 或短的斜面平面系列 (1000点) 与插曲,仍然可以产生不准确的LyE.
- 准确报告差距持续时间,数据序列长度和插值方法对于可靠的人类运动变异性分析至关重要.
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