异国情调的机械性能,通过反击不稳定性来实现
Paul Ducarme1,2, Bart Weber2,3, Martin van Hecke1,4
1Autonomous Matter and Infomatter Departments, AMOLF, Amsterdam 1098 XG, The Netherlands.
概括
研究人员开发了新的机械结构,表现出"反击"行为,对应力相反. 这一突破为先进的机械系统提供了独特的特性,如单向运动和可切换的刚性.
科学领域:
- 机械工程 机械工程
- 材料科学 材料科学 材料科学
- 不稳定的物理学 不稳定的物理学
背景情况:
- 机械断裂不稳定性在自然界和工程系统中对于传感,执行和冲击吸收至关重要.
- 现有的断裂机制与施加的力相同的方向变形.
- 没有物理定律要求这种方向变形.
研究的目的:
- 设计和实现表现出反制行为的机械结构.
- 探索反盗窃产生的新特性和应用.
- 扩大对机械系统中弹性不稳定的理解.
主要方法:
- 通过结合利用几何非线性利用灵活构建块来设计结构.
- 实验性演示的 countersnapping 结构的.
- 研究组合和合的 countersnapping 元素的行为.
主要成果:
- 经过证明的反捕获结构,在张力下缩短或在压缩下延长.
- 实现了单向的stick-slip运动,独立于系统状态的可切换刚度,以及被动共振避免.
- 展示了顺序和即时的集体刚度切换,分别是并行和串行配置.
结论:
- 反应断代表了一类新的弹性不稳定性,扩大了机械系统的设计空间.
- 这项工作为机械传感,计算和执行开辟了新的途径.
- 开发的原则可以导致具有定制响应的创新型超材料和设备.
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