Hierarchical structures are very common in nature, but only recently they have been systematically studied in materials science, in order to understand the specific effects they can have on the mechanical properties of various systems. Structural hierarchy provides a way to tune and optimize macroscopic mechanical properties, e.g. the tribological properties of a surface and the friction coefficients. For this reason we investigate the effect of hierarchical patterned surfaces on the static and dynamic friction coefficients of an elastic material. Our results are obtained by means of numerical simulations using a simplified model, the one-dimensional spring-block model, aiming to highlight some possible mechanisms that explain how hierarchical structures can significantly modify the friction coefficients of a material, providing a means to achieve tunability.
