运动节奏使得动力和速度
A Bejan1, U Gunes2, H Almahmoud3,4
1Department of Mechanical Engineering and Materials Science, Duke University, Durham, NC, 27708-0300, USA. abejan@duke.edu.
Scientific reports
|August 28, 2023
概括
青和水母等动物表现出一种快速的推-缓慢的移动节奏. 这种推进模式与设计进化有关,通过可适应的车身配置优化动力和速度.
科学领域:
- 生物力学 生物力学
- 进化生物学 进化生物学
- 流体动力学 流体动力学
背景情况:
- 许多水生和空中动物表现出一种特有的运动节奏:一个快速的推进性冲击,其次是缓慢的恢复性冲击.
- 这种节奏运动对于在流体介质中有效推进至关重要,但其演变的基本原理尚未完全理解.
研究的目的:
- 为了调查各种动物观察到的快速推-缓慢的移动模式背后的原因.
- 要确定这种推进节奏是否是自然界普遍设计进化的产物.
主要方法:
- 运动阶段的分析,重点关注动力冲动 (工作产生和消散) 和消散冲动.
- 模拟机身部分截面对周围流体 (水/空气) 的影响,以计算功率需求和动能损耗.
- 研究车身配置和设计中的进化变化如何影响机动力和速度.
主要成果:
- 预测了动力冲动中的工作产生和消散阶段的特征时间 (t1和t2) 的相对持续时间.
- 证明身体配置决定四肢速度,最大化平均功率和优化相位持续时间.
- 显示在设计进化 (自由度,空间访问) 中增加自由度可以提高机动力和速度.
结论:
- 快速推-慢到达的机车运动节奏是一个进化的设计,优化推进效率.
- 车身设计中的进化适应性是最大限度地提高在流体环境中的机动力和速度的关键因素.
- 这项研究为理解有效的生物运动的普遍原则提供了一个框架.
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