ChoreoDrops: Manipulation of Water Droplets Using Conductive Line Patterns Sparsely Printed on Paper

In this paper, we focus on water droplets and propose a novel method to control the movement of water droplets on surfaces such as paper. Most droplet movement methods based on the principle of electrowetting require a high density of electrodes to complex circuitry, and there are restrictions on the size of the droplet. In contrast, our method involves printing line-shaped electrodes on a paper-like sheet substrate and moving water droplets between these lines. The electrodes need not be densely arranged; they can be spaced several centimeters apart and water droplets can move between them. This not only greatly reduces the number of electrodes and simplifies the circuit, but also allows electrode placement with design and the ability to drive a wide range of water droplet sizes, from a few millimeters to several centimeters in diameter. This paper reports the details of the proposed method and presents several design examples.