A few weeks ago [Jasper Ruben] built his cats a jumbo size hamster exercise wheel. They seemed to like it, so he decided to up the ante and upgrade it. The wheel now features a Raspberry Pi which can track speed, calculate distance traveled, and determine the equivalent running speed of [Jasper’s] feline companions.
To calculate the speed of the wheel, [Jasper] is using a small coil sensor (similar to how bicycle speedometers work). Six nails in the wheel trigger the sensor. Once the data is on-board the Pi, some simple calculations allow [Jasper] to provide a few different metrics on how effective the cat exercise is. A webcam sends a live stream of the wheel online with a data overlay for your viewing pleasure.
The really cool part is that this setup lets [Jasper] track when (and if) the cats actually use the exercise wheel. So far it seems like they use it about six times a day, with an average of a minute per walk — typically early in the morning between 5 and 8AM. That’s better than some of our own exercise habits!