A digital microfluidic system based on electrowetting-on-dielectric is a new technology for controlling microliter-sized droplets on a plane. By applying a voltage signal to an electrode, the droplets can be controlled to move, merge, and split. Due to device design, fabrication, and runtime uncertainties, feedback control schemes are necessary to ensure the reliability and accuracy of a digital microfluidic system for practical application. The premise of feedback is to obtain accurate droplet position information. Therefore, there is a strong need to develop a digital microfluidics system integrated with driving, position, and feedback functions for different areas of study. In this article, we propose a driving and feedback scheme based on machine vision for the digital microfluidics system. A series of experiments including droplet motion, merging, status detection, and self-adaption are performed to evaluate the feasibility and the reliability of the proposed scheme. The experimental results show that the proposed scheme can accurately locate multiple droplets and improve the success rate of different applications. Furthermore, the proposed scheme provides an experimental platform for scientists who focused on the digital microfluidics system.

The digital microfluidic system based on electrowetting on dielectric is a new technology that can control microliter droplets within the plane. Because of layout, fabrication, and driving uncertainties, feedback control schemes must be designed and implemented to ensure safety and reliability of digital microfluidic system for practical application. The basis for feedback is to realize the accurate droplet location. So, there is a strong need for the development of a digital microfluidic system integrated with position and feedback scheme for innovative biological research. In this paper, we propose a position and feedback scheme based on light intensity for digital microfluidic system. The verified experiment results show that the proposed position and feedback scheme can position multiple droplets accurately and improve the success rate of droplets transport application by feedback.