Numerical analysis for the non-matting condition of dry adhesive pillararray structures

摘要

Matting phenomenon could be observed not only in the fabricated microano-scale pillar-array structure,but also in the biological nano-hair structures.In the viewpoint of the function,matting phenomenon is undesirable for the dry adhesive structure because the adhesive force could decrease.In this study,we suggested a numerical method to estimate the matting phenomena of pillar-array structure and proposed the equation of non-matting condition.We implemented the interfacial adhesion caused by van der Waals interaction as a body force term in the finite element formulation.Moreover,we showed the feasibility of the proposed method through the convergence and exactness tests.For the simplicity,we considered only two pillars in the analysis of matting.Although we assumed numerical models as plane strain state,it would be conservative to find the criterion for non-matting conditions.Several cases which have different elastic modulus,aspect ratio are examined to obtain the equation of non-matting condition.