Path-Driven Two-Stage Any-Angle Routing for Flow-Based Microfluidic Biochips

Continuous-flow microfluidic biochips (CFMBs), which can automatically manipulate fluids through microchannels, have revolutionary significance in biomedicine, drug screening, and clinical diagnosis, and have become a hot topic in recent years. The physical design directly affects the performance, reliability, and function realization of the chip. The traditional CFMBs flow-path design used the Manhattan routing. With the increasing progress of the manufacturing process, the any-angle routing of CFMBs is no longer a technical obstacle, and the any-angle routing not only improves the utilization rate of the routing resources, but also reduces the length of the flow channel. However, the existing any-angle routing algorithms do not consider the exact size of the components. In this paper, A path-driven two-stage any-angle routing algorithm is proposed to minimize the routing length, considering the shape and size of components. First, constrained delaunay triangulation algorithm is used to construct search graphs, which considers the size and shape of components, so that the subsequent path search is closer to the actual application scenario. And an improved global routing based on A* algorithm is adopted to obtain the initial path planning and resue the fluidic ports in search graph, and then the detailed routing based on dynamic programming of movable points is adopted to further optimize the length of the path. The experimental results show that compared with the existing state-of-art algorithms, the proposed algorithm keeps the same numbers of fluidic ports, and reduces the average length of the channel by 5.41%.