昆虫体壁外感觉器的应力放大传感效应

Mechanical amplification of insect campaniform sensilla

人类对天然生物所具备的应力放大功能的研究,有助于仿生开发适合于工程应用的应变传感器。在场发射电镜下观测到绿金龟子外甲壳的微观形貌,发现绿金龟子外甲壳是典型的正交逐层铺设纤维增强复合板,其上以40～50μm的间距分布着直径50～70μm的一系列近似圆形的刚毛毛窝,将这种形式表征为逐层正交铺设纤维增强带孔板,通过有限元及加权平均法计算获得孔应力放大系数为2.424,这种效应提高了外感觉器的灵敏度。进一步观测发现毛孔壁存在一种螺旋纤维结构,可抵御来自各个方向的应力集中,保护了刚毛下的毛窝腺及外体壁安全。

Research on the mechanical amplification function of natural organisms presents a bio-inspired approach for the future design of strain sensors to be embedded in engineering bodies.By the observation under FTEM,the micromorphology of chafer cuticle is found as follows：insect cuticle is a typical example of a natural composite plate with cross-fiber laminates reinforced,on the surface of which a series of trichopores with diameter of 50～70μm are distributed in the space of 40～50μm.This microstructure is characterized as a composite plate with holes with cross-fiber laminates reinforced.The stress amplification factor that helps to improve sensilla＇s sensitivity is achieved as 2.424 by finite element method and weighted average method.Furthermore continuous helicoidal fibers around the channel under trichopore are found,which resist stress concentration from every orientation and protect the gland and body wall.