Tribology Laboratories, Israel Institute of Metals, Technion, 32000 Haifa, Israel. Department of Mechanical Engineering, Azrieli College of Engineering, 26 Yaakov Shreibom St., 91035 Jerusalem, Israel.
Bioinspir Biomim. 2017 Aug 4;12(4):046010. doi: 10.1088/1748-3190/aa7720.
Hairy adhesive systems involved in gecko locomotion have drawn the interest of many researchers regarding the development of bionic solutions for fast and reversible adhesive technologies. To date, despite extensive efforts to design gecko-inspired adhesive surfaces, adhesion and friction capacities are often evaluated using smooth and rigid counterfaces, in general glass, whereas most natural and artificial surfaces inevitably have a certain level of roughness. For that reason, in this study experiments tested the effects of the substrate roughness on the friction of bionic wale-shaped microstructures for gecko-like attachments. To this end, 12 substrates with different isotropic roughness were prepared using the same Epoxy material. Friction force was measured under various normal loads. It was concluded that classical roughness parameters, considered separately, are not appropriate to explain roughness-related variations in friction force. This has led us to develop a new integrative roughness parameter that combines characteristics of the surface. The parameter is capable of classifying the obtained experimental results in a readable way. An analytical model based on the experimental results has been developed to predict the variation of the friction force as a function of counterface roughness and applied normal load.
涉及壁虎运动的粘性附着系统引起了许多研究人员的兴趣，他们希望开发出用于快速、可逆的粘性附着技术的仿生解决方案。迄今为止，尽管已经付出了大量努力来设计受壁虎启发的粘性表面，但通常使用光滑且坚硬的对置表面（通常为玻璃）来评估附着和摩擦能力，而大多数天然和人造表面不可避免地具有一定程度的粗糙度。出于这个原因，在这项研究中，实验测试了基底粗糙度对仿生波纹微结构用于类壁虎附着的摩擦的影响。为此，使用相同的环氧树脂材料制备了 12 种具有不同各向同性粗糙度的基底。在各种法向载荷下测量摩擦力。结果表明，经典粗糙度参数单独考虑时，并不适合解释摩擦力与粗糙度相关的变化。这促使我们开发了一种新的综合粗糙度参数，该参数结合了表面的特征。该参数能够以可读的方式对获得的实验结果进行分类。还基于实验结果开发了一个分析模型，以预测摩擦力随对置表面粗糙度和法向载荷的变化。
