Meeting Abstract
While artificial suctions cups can stick to smooth substrates, Northern clingfish have the remarkable ability to stick to surfaces with a large range of roughness. We know that the hierarchical structures on the margin of the suction disc (papillae (~150µm) that are covered with rods (~5µm), which themselves are divided into small filaments at their tips (~0.2µm)) enable adaptation to the irregularities of the substrate surface. We also assumed that the low stiffness of the suction disc lays a crucial role to adapt to the surface. In the current study we used a biomimetic approach to investigate the affects of the elasticity of the suction cup on its ability to attach to rough surfaces. We produced suction cups of the same shape with different elasticity (Young’s modulus from 0.155-2.4 MPa) and measured attachment time to various substrate roughness (0-269 µm grain size). We found that stiffer suction cups attach for shorter times to rougher substrates than softer, more elastic suction cups. Suction cups made from materials with elasticity closest to the clingfishes (Gobiesox maeandricus) showed the best attachment suggesting an optimum elasticity for a given substrate.
