车身运动会影响轮椅推进过程中的机械功率估计
Marit P van Dijk1, Marco J M Hoozemans2, Monique A M Berger3
1Department of Biomechanical Engineering, Delft University of Technology, Delft, The Netherlands.
Journal of biomechanics
|January 11, 2024
概括
轮椅推进中的车体运动会影响滚动阻力,这导致在使用标准阻力测试时机械功率被低估. 精确的功率测量需要考虑上半身运动.
科学领域:
- 生物力学 生物力学
- 运动科学 运动科学 运动科学
- 康复工程 康复工程
背景情况:
- 精确测量机械功率对于轮椅运动的表现和训练至关重要.
- 惯性测量单元 (IMU) 可以估计功率,但依赖于准确的滚动阻力数据.
- 箱体运动会改变轮椅的质量分布,这可能会使标准滚动阻力测量失效,例如阻力测试.
研究的目的:
- 为了研究行李箱运动对机械功率估计的影响,在手臂轮轮椅推进过程中.
- 为了比较使用瞬间滚动阻力计算的功率损失与阻力测试衍生的滚动阻力.
- 为了量化低估机械功率的数量,当忽略了干部运动效应时.
主要方法:
- 轮椅推进实验是以不同程度的车运动 (没有,中等,完全) 进行的.
- 使用两种方法计算机械功率损耗:即时滚动阻力和基于阻力测试的滚动阻力.
- 统计分析,包括平均差异 (MD) 和相关性 (r),用于比较方法.
主要成果:
- 当没有发生干运动时,功率损失估计是相似的 (0.6 ± 1.6% MD).
- 随着车体运动的增加,基于阻力测试的功率损失被低估了高达-3.3 ± 2.3%的MD (r = 0.85).
- 忽视干部运动导致机械功率低估1-6%.
结论:
- 车身运动显著影响轮椅推进中的滚动阻力.
- 标准的阻力测试低估了机械功率,当有活跃的车体运动时.
- 为准确估计轮椅运动中的机械功率,建议对车身运动效应进行校正.
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