Title: Granular self organization by autotuning of friction

Author (Poster): Deepak Kumar, University of Massachusetts Amherst

Abstract:

We study a monolayer of macroscopic spherical particles being driven over a substrate by a potential, symmetric about its minimum, moving at a constant speed. While being driven in a symmetric confining potential, the system self organizes to form a distinctively asymmetric structure which occupies only the rear half-space. The regulation of motion of individual spheres occurs via toggling between two types of motion, namely, rolling and sliding, which differ substantially in coefficients of friction. The global features of the structure are maintained robustly by autotuning of friction through these internal states.