Coordination of droplets on light-actuated digital microfluidic systems

In this paper we explore the problem of coordinating multiple droplets in light-actuated digital microfluidic systems intended for use as lab-on-a-chip systems. In a light-actuated digital microfluidic system, droplets of chemicals are actuated on a photosensitive chip by moving projected light patterns. Our goal is to perform automated manipulation of multiple droplets in parallel on a microfluidic platform. To achieve collision-free droplet coordination while optimizing completion times, we apply multiple robot coordination techniques. We present a mixed integer linear programming formulation for coordinating droplets given their paths. This approach permits arbitrary droplet formations, and coordination of both individual droplets and batches of droplets. We then present a linear time stepwise approach for batch coordination of droplet matrix layouts.