Attendance describes a speculative ambient body-centric design project in which a the relative location of a roster of people are loosely tracked. A family (or a cohort of grad students, perhaps) each have an entry on a fixture (which could be expressed multiple ways – for the purposes of this project I imagined working with shape-memory alloys) that highlights when those people are nearby.
Above is a rough sketch of the fixture realized with shape-memory alloys: lengths of wire twist into an approximation of the person’s name when they are close, and unwind into nothingness when they are away. Below is the same concept rendered with LEDs on a flat clock-face. This project was researched and coded with the theoretical understanding that it would be realized with lengths of shape-memory alloy wiring.
I started by setting up feeds in Adafruit IOand a pair of IFTTT applets
to track my location and interface with Adafruit IO. When I enter a radius around campus it sends “1” to the “arrived” feed, and when I leave the radius it sends “1” to the “gone” feed.
A little walking demonstrated that IFTTT and Adafruit IO were interfacing correctly: below you can see that the feeds successfully tracked the instances when I left for lunch and when I returned.
Without shape-memory alloys to play with I had to get speculative with the code. I did some research and learned that SMAs require careful voltage, with some trial and error depending on size. I set up my code to use a transistor and pulse width modulation so that when it is eventually hooked up to SMA I can find the ideal voltage for it.
In the photo below the LED is in the place of the shape-memory alloy.
It took me a fair bit of digging to figure out how to monitor multiple Adafruit feeds in one sketch, and I continue to have some trouble with the syntax of the functions in the Gone/Arrived sections of the code.
I’d like the chance to work with shape-memory alloys properly and expand this concept – until then, I can prove the concept with an LED.