Structural damping renders the hawkmoth exoskeleton mechanically insensitive to non-sinusoidal deformations
Structural damping renders the hawkmoth exoskeleton mechanically insensitive to non-sinusoidal deformations
复制标题
结构阻尼使鹰蛾外骨骼对非正弦变形机械不敏感
DOI：
10.1098/rsif.2023.0141
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发表时间：
2023
影响因子：
3.9
通讯作者：
Sponberg, Simon
中科院分区：
文献类型：
--
作者：
Wold, Ethan S.;Lynch, James;Gravish, Nick;Sponberg, Simon
肌肉通过弹性和耗散元素来调节运动，这可以引入消散和过滤，这对能量学和控制很重要。昆虫的外骨骼可以降低拍打飞行的高功率要求，它充当的是在纯正弦变形下具有与频率无关的材料特性的弹簧。然而，这种纯粹的正弦动态机制并不包括许多昆虫的不对称翅膀击打或由外部扰动引起的非周期性变形。因此，目前尚不清楚频率无关模型是否适用范围广泛，以及它对控制有何影响。我们使用振动测试系统测量了对称、非对称和带限白噪声变形下孤立的Manduca六胸的力学性能。非对称和白噪声条件代表了在稳态和扰动飞行过程中可能遇到的两种类型的广义多频变形。在对称和不对称情况下，能量节约和耗散是无法区分的，这表明不需要额外的能量来使胸腔非正弦变形。在白噪声条件下，胸腔的刚度和阻尼值随频率变化不变，说明胸腔不具有频率相关的滤波特性。一个简单的平坦频率响应函数适合我们测量的频率响应。这项工作证明了具有频率无关阻尼的材料通过消除粘弹性元件通常在肌肉和机翼之间施加的任何速度相关的滤波来简化电机控制的潜力。
Muscles act through elastic and dissipative elements to mediate movement, which can introduce dissipation and filtering which are important for energetics and control. The high power requirements of flapping flight can be reduced by an insect's exoskeleton, which acts as a spring with frequency-independent material properties under purely sinusoidal deformation. However, this purely sinusoidal dynamic regime does not encompass the asymmetric wing strokes of many insects or non-periodic deformations induced by external perturbations. As such, it remains unknown whether a frequency-independent model applies broadly and what implications it has for control. We used a vibration testing system to measure the mechanical properties of isolatedManduca sextathoraces under symmetric, asymmetric and band-limited white noise deformations. The asymmetric and white noise conditions represent two types of generalized, multi-frequency deformations that may be encountered during steady-state and perturbed flight. Power savings and dissipation were indistinguishable between symmetric and asymmetric conditions, demonstrating that no additional energy is required to deform the thorax non-sinusoidally. Under white noise conditions, stiffness and damping were invariant with frequency, suggesting that the thorax has no frequency-dependent filtering properties. A simple flat frequency response function fits our measured frequency response. This work demonstrates the potential of materials with frequency-independent damping to simplify motor control by eliminating any velocity-dependent filtering that viscoelastic elements usually impose between muscle and wing.
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影响因子：
5.3
作者：
Cowan, Noah J.;Fortune, Eric S.
通讯作者：
Fortune, Eric S.
影响因子：
3.3
作者：
Gau, Jeff;Wold, Ethan S.;Sponberg, Simon
通讯作者：
Sponberg, Simon
影响因子：
--
作者：
F. Zajac
通讯作者：
F. Zajac
影响因子：
2.8
作者：
Fernandez, Maria Jose;Springthorpe, Dwight;Hedrick, Tyson L.
通讯作者：
Hedrick, Tyson L.
DOI：
--
发表时间：
1997-11
期刊：
The Journal of experimental biology
影响因子：
--
作者：
A. Willmott
通讯作者：
A. Willmott