Feedback control of inertial focusing using real-time extraction of equilibrium positions

Inertial microfluidics has facilitated promising applications of lab-on-a-chip devices for high-throughput biological analysis. However, as the mechanism of inertial microfluidics remains largely unknown, there are many difficulties in obtaining the desired equilibrium positions; hence, most researchers have tried to modify the channel geometry to obtain the desired equilibrium positions. In this paper, to improve the consistency of inertial focusing experiments, we apply feedback control to inertial focusing devices. The feedback control was realized by an image processing algorithm for real-time measurement of equilibrium positions using a high-speed vision system. The proposed image processing algorithm and feedback control scheme were verified through experiments.