Capillary surfers: Wave-driven particles at a vibrating fluid interface

Abstract

We present an experimental study of capillary surfers, a new fluid-mediated active system that bridges the gap between dissipation-and inertia-dominated regimes. Surfers are wave-driven particles that self-propel and interact on a fluid interface via an extended field of surface waves. A surfer's speed and interaction with its environment can be tuned broadly through the particle, fluid, and vibration parameters. The wave nature of interactions among surfers allows for multistability of interaction modes and promises a number of novel collective behaviors.

Synchronized Surfing of Self-Propelled Particles

“…Some self-propelled objects can travel in both flow regimes, a possibility that is less explored. Daniel Harris at Brown University, Rhode Island, and colleagues have studied the motion of a new system of self-propelled objects that move in this intermediate regime, finding that the objects organize into several distinct and tunable motion patterns [1]. The researchers say that their surfers may serve as a versatile, accessible model system for developing a detailed understanding of active matter in the intermediate flow regime.…”