Similar to my first concept, this second idea for my Physical Computing final also involves the use of thermochromic inks in creating a “live, reflective painting.” This will be achieved using a piece of canvas with a layer of body temperature-activated thermochromic ink. Behind the canvas will be an intricate grid of tin or copper hexagons, each individually controlled/heated by resistive wire. Above the canvas will be a small webcam that will detect shapes of people or objects placed in front of the canvas. A Processing sketch will then translate the feed into grayscale values and through serial communication, the Arduino will in turn read those values and send a current to heat its respective hexagon pixel behind the canvas. As a result, the person would then see their own reflection emerging on the canvas.
A PWM multiplexer may be needed to control each hexagonal piece individually. Using a relay, I hope to be able to control the amount of heat emitted and therefore manipulate the color changes to create shading and depth. The first step is to experiment with the ink itself and determine which heating mechanism is 1) safe and 2) allows for the most control over the ink. Other heating element options to consider: incandescent C7 lightbulbs, peltier units, electric socks hack.