Cat Wheel Speedometer
How fast and far is your cat walking? Sarah Dalrymple's project measures exercise wheel movements using magnets and an ESP32.
Cats, like any domesticated creature, need exercise. While climbing around on shelves and playing with faux mice can provide movement and entertainment, for more structured exercise you could provide your cat with a wheel that rotates and rotates… and rotates when it walks/runs around inside. But just how far is your cat walking?
To answer that question, Sarah Dalrymple came up with the Cat Wheel Speedo. This odometer/speedometer uses a reed switch module to sense when magnets embedded on the moving wheel pass by, sending pulses to an ESP32 board that records this data. An LCD module with I2C displays movement values, and stats are reset when the power is pulled.
Dalrymple used four magnets for this wheel setup. A little measurement and math gives 0.85 meters per magnet passing, allowing it to calculate the cat speed and total distance. Electronics are housed in a small plastic box that finishes off the build.
While the speedometer features only local display at this point, given that it uses an ESP32 for processing, the hardware is there for Wi-Fi and/or Bluetooth interface as a connected cat exercise monitor. Code is available via the project write-up, along with a short demo clip, and the same concept could be applied to a hamster wheel or similar setup. As far as actually getting a cat to use this device, that is up to you (though she does suggest this video)!
