Hamster Wheel Tachometer

Around three years ago, B.Rick’s nephews got a hamster named Nugget. Like many domestic rodents, this little creature would run and run on a little wheel to get exercise. Naturally, they were curious as to just how far it would go each night, and just how fast. While this project was completed posthumously for Nugget, during early experimentation the hamster was able to run .3 miles per night and achieve a rotational speed of 100 RPM on its little wheel. Amazing stats for something that weighs well under a pound.

Early experimentation involved an Arduino Duemilanove, a retroreflective optional sensor, and an SD card data logging shield. The new version is a bit more refined, using an IR sensor and emitter to produce and measure light that bounces off its plastic exercise wheel. A piece of black felt is stuck on a section of the wheel to interrupt its “presence,” enabling the system to detect when a revolution has been accomplished.

The tachometer shows stats on a 0.54” LED alphanumeric display, including the hamster’s highest speed in RPM, as well as the total number of revolutions that it has run. The device runs on an Adafruit Feather 32u4 Basic Proto PCB, with an ATmega32U4 and a nice breadboarding area. Code, along with 3D print files, are available in the project's write-up, allowing you to see what kind of mini-marathons your hamster is running each night.