For our midterm, Rushali had the great idea of sensing toilet paper use wirelessly and keeping track of it. After making a list of potential sensors that could detect movement and looking at the hardware in the bathroom, we realized that it would be hard to detect the kind toilet paper use we were interested in sensing and measuring. But, the paper towel dispenser had a springs in it that we thought could easily detect a pull with a simple stretch sensor. Next, we decided our output triggered by the pull should be a gif. We wrote a p5 program that pulls from the giphy API to create a series of arrays, and auto-updates at a set time interval. When a paper towel is pulled out of the dispenser, a random gif is pulled from the array, and updates each time a paper towel is pulled.
Actually setting up and deploying our circuit into the real world proved challenging! But we were able to hook everything up and insulate our circuit from the metal in the dispenser to get our prototype working.
After we had a wired version working the way we wanted, we set out to make it wireless with bluefruit! Once we had our sensor installed, we didn’t want to keep removing it and putting it back, so we tested out our wireless circuit with a potentiometer first. Then, we hooked everything up in the paper towel dispenser and it kind of worked. There was a noticeable delay between when the paper towel was pulled and when the gif changed.
As next steps we discussed potentially keeping the data on paper towel use, since right now we aren’t saving it or keeping track of it in any way. Of course it would also be great to improve the wireless functionality and try to keep it running for a longer period of time. I imagine we could also serve our p5 sketch so that anyone could go to our app and see the gifs change as paper towels get used.
One concern we had is we made using paper towels more fun, so we might be encouraging their use! We thought it might be better to show deforestation gifs. Either way, it was a great way to experiment with sensing things in the real world.