A Best Path Selection Based Parallel Router for DMFBs

Recent advances in the design of digital micro fluidic based biochips have revolutionized the area of biochemical analysis especially for low-cost, portable, and disposable devices targeted towards clinical diagnostics applications. A promising category of micro fluidic biochips relies on the principle of electro wetting-on-dielectric, whereby discrete droplets of nanoliter volumes can be manipulated using an array of electrodes. This emerging technology combines electronics with biology to open new application areas such as point-of-care diagnosis, on-chip DNA analysis, and automated drug discovery. With the rapid advancement in micro fluidic and micro fabrication technology the complexity of design is expected to increase enormously as the number of concurrent application of assays in a single device increases significantly. One of the major CAD issues in this area is the concurrent routing of droplets in the design of DMFBs. The objective of droplet routing is to schedule the movement of a number of droplets in a time multiplexed manner to avoid their cross contamination. In this paper we attempted to resolve this problem using a line probe based algorithm to estimate all possible routing paths for each droplets. Thereby we used a graph based model to select the most suitable path for each droplet in the context of collision avoidance, minimization of stalling and optimized utilization of resources. The algorithm guided with problem specific heuristics has been tested with a number of standard test benches and the experimental results obtained so far indicate encouraging developments.