在稳定状态行走过程中,使用优化模板模型进行质量运动重建的中心
David J Kelly1, Patrick M Wensing1
1Aerospace & Mechanical Engineering Department, University of Notre Dame, Notre Dame, Indiana, United States of America.
PloS one
|November 5, 2024
概括
机动模型中的可变腿部度显著降低了质量中心误差,并改善了地面反应力预测,提高了人类步行模拟的准确性.
科学领域:
- 生物力学 生物力学
- 机器人技术 机器人技术 机器人技术
- 人类的机动运动
背景情况:
- 模板模型,如双脚弹加载反转吊 (B-SLIP) 和虚拟转点 (VPP) 简化了腿部运动动态.
- 这些模型质量上与人类步行相匹配,但高估了质量中心 (CoM) 位移,低估了步行事件时间.
研究的目的:
- 调查假设,模板模型中的恒定腿度会导致与人类行走数据的差异.
- 系统地评估可变腿度对模型忠实性和人类行走特征的影响.
主要方法:
- 开发了一个优化框架,以确定最佳的腿度轨迹.
- 该框架应用于24个不同步行速度的受试者 (40% -145%的受试者偏好步行速度).
- 测量了刚度变化对地面反应力 (GRF) 和步行事件时间的影响.
主要成果:
- 在B-SLIP和VPP模型中,可变腿度模型将CoM误差降低了80%以上.
- 观察到人类GRF形状的预测得到了改善,硬度可变.
- 步行事件定时的准确性在所有条件下都没有持续改善.
结论:
- 可变的腿部性对于准确模拟人类行走动态,特别是CoM位移和GRF概况至关重要.
- 优化的刚性配置反映了生物力学策略,如脚推卸和减少CoM顶.
- 可能需要进一步的研究来改善这些模型中的步态事件时间预测.
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