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Droplet-based transport phenomena driven by surface tension have been explored as an automated pumping source for a number of chemical and biological applications. In this paper, we present a comprehensive theoretical and experimental investigation of unconventional droplet-based motions on a superhydrophobic-patterned surface microfluidic (S2M) platform. The S2M surfaces are monolithically fabricated using a facile two-step laser micromachining technique on regular polydimethylsiloxane (PDMS) chemistry. Unlike the traditional droplet-driven pumps built on an enclosed microfluidic network, the S2M network pins the liquid–solid interface of droplets to the lithographically defined wetting boundary and establishes a direct linkage between the volumetric and hydraulic measures. Moreover, diverse modes of droplet motions are theoretically determined and experimentally characterized in a bi-droplet …