Boundary-Driven Droplet Control: Programmable Volumetric Operations via Spinner Arrays

We present a programmable fluidic platform for droplet generation and manipulation using spinner arrays that create boundary-driven transport, mimicking biological systems. Our channelless design enables control over droplet size and dripping frequency through multiple, independently programmable droplet generators. By dynamically adjusting spinner configurations, we achieve real-time steering of droplets to target locations, supporting volumetric operations for combining different chemistries. This programmable approach offers a flexible platform for droplet-based applications, providing new capabilities for controlled chemical reactions, material assembly, and soft matter physics, while enabling experimental investigation of multi-component droplet processes. This establishes a new paradigm in droplet-based fluidics.