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This study investigated the adhesion (pull-off) force and contact angles of a water strider's leg. During hydrostatic experiments, the adhesion force was found to be 2 dyn. The image of a cross section of a live leg contacted with a deformed water surface provided the contact angle of 168.8 degrees . A numerical scheme was proposed to determine the water surface on a groove wall of a seta. The results showed that the asperities of a seta are almost wetted, and the fraction of the wetted projection area was 0.69. Thus, the contact angle of a seta was 124.8 degrees .

This study investigated the forces and the cross-section images of a water strider's leg through experimental observations. In the vertical direction, the spring coefficients were found to be 0.6 N/m for the leg and 0.3 N/m for the water, which provide a water-treading stiffness of 0.2 N/m. In the horizontal directions, besides the alignment of the microsetae, the large cuticle forces were also related to the resistant side in a Wenzel state.

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Detailed observations for the initial and adhesive contact of polydimethylsiloxane indentations with sharp indenters are proposed and discussed in this study. In dry experiments, the load-depth results revealed an almost reversible feature, which indicated elastic deformation. Significant initial penetration depths, created during the finding surface process, were found. A power-law relationship was used to illustrate the initial portion of the loading curve and to evaluate the initial penetration depth for correcting depth measurements. An axisymmetrical indenter with a sticky boundary condition was applied to illustrate the results of dry experiments. When the load exceeded a specific value, both loading and unloading results showed an invariant slope. The analysis of the sticky indenter provided a reasonable explanation for the linear load-depth results. By correcting the initial penetration depth, the evaluated Young's modulus values, obtained from the indenters with different geometries and under different environments, were shown to be unique and accurate.