This video showcases the Open Drop, a medical research device designed for manipulating microscopic water droplets, ingeniously repurposed for playing classic video games like Snake, Pac-Man, and Crossy Road. The creator details his journey from acquiring the device to programming it, including a trip to Switzerland to understand its Arduino-compatible, Java-based firmware. The core of the device's functionality is explained through "electrowetting," where applying voltage to an array of electrodes on a dielectric surface alters its hydrophilicity, attracting and moving water droplets. The video demonstrates how droplets can be precisely controlled, merged, and even shaped into complex forms by "sandwiching" them under glass, which also facilitates its intended medical applications such as automated dilution and sample testing. Despite challenges in programming and device interaction, the creator successfully adapted the games, highlighting the Open Drop's open-source nature and inviting community contributions for future modifications.
Exploring the Open Drop: From Medical Research to Water Droplet Gaming
0:00 Repurposing a Medical Device: The creator demonstrates an "Open Drop" medical research device, originally designed for manipulating water droplets, being used to play classic video games like Pac-Man and Snake.
0:19 Acquiring and Hacking the Device: Driven by curiosity and a desire to play Snake on it, the creator purchased the Open Drop (costing nearly β¬1,000) and embarked on a journey to write custom code.
0:50 Learning the Open Drop's Architecture: To understand how to program the device, the creator visited Gordens, the inventor in Switzerland, learning about its Arduino-compatible firmware and the Java-based "processing" platform used to send binary commands for electrode control.
2:07 The Science of Electrowetting: The video explains the core principle: electrowetting. Applying voltage to tiny metal electrodes covered by a dielectric coating creates an electrical charge, making the surface more hydrophilic and attracting polar water molecules.
4:58 Droplet Movement Explained: Droplets are moved by sequentially turning off the current electrode and activating an adjacent one, causing the water to "scoot" over.
5:11 Multi-Droplet Control and Frogger: The device can control multiple droplets simultaneously. A challenge is that droplets merge irreversibly upon contact, a feature ironically suited for games like Frogger/Crossy Road where contact with "cars" signifies an end.
6:58 Pac-Man Adaptation and Mass Conservation: The creator successfully implemented Pac-Man, but noted that the "Pac-Man" droplet grows larger with each "ghost" eaten, unlike the original game, due to mass conservation.
7:25 Snake and the Glass Sandwich Solution: Snake is presented as a perfect fit for the device due to its inherent mass conservation. To allow for complex "snake" shapes, water droplets are "sandwiched" under glass, reducing surface tension's influence.
8:16 Intended Medical Applications: The video briefly demonstrates the Open Drop's primary function: automated fluid handling for medical research, including precise dilution, multi-sample testing, and creating dynamic fluid channels.
9:05 Programming Challenges and Game Mechanics: Delivering new "fruit" for Snake was the hardest coding aspect, requiring the game to pause during the delivery sequence to avoid collisions.
9:53 Open Source and Future Plans: The Open Drop's open-source nature allows for custom electrode arrays and community contributions. The creator plans a future video running viewer-submitted code and offers an incentive for the first working Tetris version.
11:00 Sponsor Message: Data Privacy: The video concludes with a sponsored segment on Incogni, a service that helps users remove their personal data from data brokers, highlighting the risks of data breaches and unwanted solicitations.