Analytical model of adhesion for analyzing biological and synthetic nanostructured fibrillar adhesive pads

Geckos are well recognized for their ability to cling to any type of surface. Previous studies reveal that thousands of fibrils on the toe tip of these animals produce enough force to carry their body weight by employing Van der Waals forces. Various mechanical models have been developed to describe these specific fiber-array structures. Almost in all of them fiber-array structures are assumed as array of cylindrical contact elements with constant height and similar length in contact with smooth surface. The present study demonstrates a novel analytical model capable of studying the effects of natural variations of contact elementspsila diameter and uneven contact surface on the total pull-off force produced. The results produced by this model show good agreement with previous experimental and natural observations.