firebase

2 Articles

Aquassist fish feeder

2025 Pet Hacks Contest: Aquassist Fish Feeder

May 23, 2025 by No comments

This project submitted to the 2025 Pet Hacks Contest brings a bit of IoT to your finned friends. Aquassist is a fish feeder that is primarily 3D printed only requiring a servo and a microcontroller to give you remote control of feeding your fish.

The Aquassist consists of just six 3D-printed parts. At its core is an Archimedes screw, a mechanism that ensures consistent portions of fish food are dispensed into the fish tank. A small hopper on top holds the food, and to minimize the part count, all 3D-printed components are designed to be glued together.

The brains of the operation take place in a Wemos D1 mini, a compact ESP8266 board programed using the Arduino IDE. The feeding mechanism relies on an SG90 continuous rotation servo, which rotates the Archimedes screw to dispense food. Unlike standard servos, this model offers ample torque in a small package and can rotate continuously without hitting an angular limit.

The Aquassist is controlled via a web-based application accessible from any device. The D1 Mini connects to Firebase to check the feeding schedule or detect if the “Feed Now” button has been pressed. Users can set feeding times or trigger an immediate feeding through the app’s intuitive interface. Check out a video below to see the Aquassist in action, and check our our other entries into the 2025 Pet Hacks Contest.

Continue reading “2025 Pet Hacks Contest: Aquassist Fish Feeder” →

21st Century Cheating: WiFi In A Calculator

May 7, 2020 by 48 Comments

Obviously, we would never endorse cheating on an exam, but sometimes a device is just too tempting to be left untouched. For [Neutrino], it was an old Casio calculator that happened to have a perfectly sized solar panel to fit a 128×32 OLED as replacement. But since the display won’t do much on its own, he decided to connect it to an ESP8266 and mount it all inside the calculator’s housing, turning it into a spy-worthy, internet-connected cheating device, including a stealthy user interface controlled by magnets instead of physical buttons. (Video, embedded below.)

Editor’s Update: Please read our follow-up coverage to the copyright claims made against this project. The video linked above and embedded below are unavailable due to these claims, despite widespread belief that this project does not violate copyright. For now, the original video is available via the Internet Archive.

To achieve the latter, [Neutrino] added two Hall effect sensors and a reed switch inside each end of the calculator. Placing a magnet — possibly hidden in a pen cap — near the reed switch will turn the display on, and placing another magnet near the Hall-effect sensors will navigate through the display’s interface, supporting two inputs with long, short, and multi-tap gestures each. To obtain information through WiFi, the ESP8266 connects to Firebase as backend, allowing to set up predefined content to fetch, as well as a possibility to communicate with your partner(s) in crime through a simple chat program.

As the main idea was to keep visible modifications to a minimum, one shortcoming is that charging the additional battery that powers the whole system would require an additional, external charging circuit. But [Neutrino] had a solution for that as well, and simply exposed two wires to the back, which could easily be mistaken for random solder splatters. And well, of course, requiring WiFi might also be tricky in some situations, so maybe you might want to consider a mobile network upgrade for yourself.

Continue reading “21st Century Cheating: WiFi In A Calculator” →