Final Project Proposal: DIY Smart Litterbox

As adults, we have the right to only be responsible for our own poop. But when you own an indoor cat, you give up that right. Your cat’s poop  becomes your responsibility.

It’s never fun to find out that it’s time to change out the litter in your cat’s indoor bathroom (i.e. litter box). Smell is the key indicator, and who likes to sniff around for a bad smell?

Enter, the smart litter box sensor:


The sensor detects the excess ammonia gas emanating from an uncleaned litter box. In response, it has two outputs: it lights up two LEDs (behind each eye in the little kitty head), and it sends an SMS (text message) to the keepers of the litter box (i.e. the pet’s owner(s)/parent(s)).

I’ve already prototyped a non-texting version of this product:


< Sketch of wiring diagram for sensor, 2 LEDs and Arduino board


< Soldering/wiring process for sensor and LEDs


< 3D-printed enclosure for the sensor, LEDs and wires (it’s too small!)

And now it’s time to add the text-sending functionality to the equation. This will require:

  • A WiFi-capable circuitboard, like the Huzzah Feather (already purchased)
  • Getting my existing code to work on this new board (work in progress!)
  • Adding a text-sending functionality by parsing through how-to guides like these:
  • 3D modeling of a new container that fits my wiring and my new circuit board!