A Theoretical Characterization of Curvature Controlled Adhesive Properties of Bio-Inspired Membranes
A Theoretical Characterization of Curvature Controlled Adhesive Properties of Bio-Inspired Membranes
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DOI：
10.3390/biomimetics1010003
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发表时间：
2016-12-01
期刊：
影响因子：
4.5
通讯作者：
Carbone, Giuseppe
中科院分区：
文献类型：
--
作者：
Afferrante, Luciano;Heepe, Lars;Carbone, Giuseppe
一些生物系统，如树蛙（Litoria caerulea）和蟋蟀（Tettigonia viridissima），已经发展出通过改变其垫的曲率来控制粘附的能力。受这些生物模型启发的粘附主动控制系统对于开发具有可控粘附特性的设备可能非常有吸引力。在本文中，我们提出了一个理论，描述了一个人工系统的粘附行为的可充气膜夹在一个金属圆柱和充满空气。在这样的系统中，通过控制作用在膜上的内部压力，可以调节粘合强度。特别地，内部压力的增加以及因此膜的曲率的增加导致拉脱力的减小。理论模型预测的结果与实验数据吻合较好。该模型解释了明显的矛盾的结果观察到的厚膜与零曲率。事实上，在这种情况下，应该预期大的拉脱力，但是由于压头和膜之间的初始小的未对准而测量到零值，这在实验期间不可能精确控制。本模型可能有助于更好地理解生物系统和指尖的粘附行为，从广义上讲，指尖可以被视为壳状结构。
Some biological systems, such as the tree frog, Litoria caerulea, and the bush-cricket, Tettigonia viridissima, have developed the ability to control adhesion by changing the curvature of their pads. Active control systems of adhesion inspired by these biological models can be very attractive for the development of devices with controllable adhesive properties. In this paper, we present a theory describing the adhesive behavior of an artificial system consisting of an inflatable membrane clamped to a metallic cylinder and filled with air. In such a system, by controlling the internal pressure acting on the membrane, it is possible to modulate the adhesive strength. In particular, an increase of the internal pressure and, hence, the curvature of the membrane, results in a decrease of the pull-off force. Results predicted by the theoretical model are in good agreement with experimental data. The model explains the apparent contradictory results observed for the thick membrane with zero curvature. In fact, in this case, large pull-off forces should be expected, but zero values are measured due to an initial small misalignment between indenter and membrane, which is not possible to control with precision during the experiments. The present model might help to achieve a better understanding of the adhesion behavior of biological systems and of the fingertips that, in a broad sense, may be regarded as shell-like structures.