This is not a hamster.
(I could stare at that all day.)
Cat owners among you with hard floor coverings will recognise the eldritch skittering of tiny paws at the witching hour, when all cats believe they have become rally cars. The owner of Jasper and Ruben (who, when researching this post, I thought was called Jasper Ruben; he remains anonymous for now – please leave a comment with your name if you’d like to!) has mechanised the problem. With a Raspberry Pi, natch.
This is the web interface for Jasper and Ruben’s wheel. Cat-propelled, and Raspberry Pi-monitored, it logs distance travelled, average speed, duration of feline whirring, and all that good stuff, and displays the statistics in real time.
Here’s the back, where the clever happens. (And the top of Ruben’s head.)
The Pi’s GPIO is hooked up to a coil sensor behind the wheel, which is housed in an old DSL splitter box, held as close as possible to the wheel without actually touching it (the turquoise nubbin in the picture). A coil sensor detects magnetic field, so the wheel itself has some modifications to make it detectable and measurable: six small ferrous nails hidden in the lining.
The Pi drives a camera board and interprets the feedback from the sensor, so it can display live statistics as the cat runs. It also enables the user to record any particularly nifty bits of cat-sprinting.
Being human, you want to see more video of the setup in action. Here’s Jasper, being taunted by a laser dot, with real-time stats at the top of the video.
And here’s proof that the cats will use the wheel spontaneously:
We want to see someone modify this to use the wheel’s rotation to charge a battery. What would you use it to power? (I’m thinking kibble dispenser…)