Bioinspired Vibration-Induced Droplet Depinning Enables Extraction of Particulates Buried Within Surface Asperities

Nature has evolved resourceful strategies to sustain hygiene by enabling organisms to dislodge contaminants through the synergy of water-repellent integuments and kinetic energy generated by organismal motion. In this study, an efficient vibration-driven surface cleaning platform for pinned droplet separation is developed, inspired by the natural strategy of Aves that combines water-repellent feathers with compensatory wing flapping motion. Counterintuitively, unlike superhydrophobic surfaces that hinder droplet-contaminant interaction, the feather-like hydrophobic films promote such interaction and enable droplet release through vibration for efficient cleaning. To quantify the vibrations required to separate droplets on hydrophobic surfaces, an energy-based framework is formulated based on a fluid dynamics model that treats the droplet as an elastic body, enabling analysis of how vibration and gravity affect interfacial adhesion and definition of separation criteria across surface wettabilities. The developed surface technology demonstrates efficient removal of fine particulates embedded within surface asperities, addressing a cleaning regime that remains challenging for conventional superhydrophobic surfaces. This capability highlights its potential to support applications in optical sensors and mobility platforms where consistent surface cleanliness and visibility maintenance are critical.