Switchable Adhesion via Subsurface Pressure Modulation
Switchable Adhesion via Subsurface Pressure Modulation
复制标题
通过地下压力调节可切换粘附力
DOI：
10.1021/acsami.0c05367
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发表时间：
2020
影响因子：
9.5
通讯作者：
Shan, Wanliang
中科院分区：
文献类型：
--
作者：
Mohammadi Nasab, Amir;Luo, Aoyi;Sharifi, Siavash;Turner, Kevin T.;Shan, Wanliang
具有可调干附着力的材料和设备有许多应用，包括转移印刷、攀爬机器人和在拾取和放置过程中的抓取。本文介绍了一种通过调节地下气动压力实现干附着动态可调的软装置。具体来说，研究了一种圆柱形弹性体支柱，该支柱具有蘑菇形状的帽和环形腔，可以加压以调节附着力。基于有限元的力学模型和实验用于设计、理解和演示设备的粘附性。具体来说，该装置采用力学建模设计，使得环形腔内施加的压力显著改变了粘附界面的应力分布，从而改变了有效粘附强度。由具有不同弹性模量的聚二甲基硅氧烷（PDMS）制成的装置在玻璃、硅和铝基板上进行了测试。在非加压状态下，粘接强度（σ0）范围从~ 37 kPa （PDMS与玻璃之间）到~ 67 kPa （PDMS与抛光铝之间）。在所有情况下，无论衬底的材料和粗糙度如何，当腔室压力从0.3σ0增加到0.6σ0时，附着强度下降到非加压状态强度的40%（相当于2.5倍的附着切换比）。当腔室压力增加到σ0时，强度下降到未加压强度的20%（相当于5倍的粘附切换比）。
Materials and devices with tunable dry adhesion have many applications, including transfer printing, climbing robots, and gripping in pick-and-place processes. In this paper, a novel soft device to achieve dynamically tunable dry adhesion via modulation of subsurface pneumatic pressure is introduced. Specifically, a cylindrical elastomer pillar with a mushroom-shaped cap and annular chamber that can be pressurized to tune the adhesion is investigated. Finite element-based mechanics models and experiments are used to design, understand, and demonstrate the adhesion of the device. Specifically, the device is designed using mechanics modeling such that the pressure applied inside the annular chamber significantly alters the stress distribution at the adhered interface and thus changes the effective adhesion strength. Devices made of polydimethylsiloxane (PDMS) with different elastic moduli were tested against glass, silicon, and aluminum substrates. Adhesion strengths (σ0) ranging from ∼37 kPa (between PDMS and glass) to ∼67 kPa (between PDMS and polished aluminum) are achieved for the nonpressurized state. For all cases, regardless of the material and roughness of the substrates, the adhesion strength dropped to 40% of the strength of the nonpressurized state (equivalent to a 2.5× adhesion switching ratio) by increasing the chamber pressure from 0.3σ0to 0.6σ0. Furthermore, the strength drops to 20% of the unpressurized strength (equivalent to a 5× adhesion switching ratio) when the chamber pressure is increased to σ0.