[Fast Co Design]

… His approach is a compromise between boundless childhood imagination and human factors of practicality: He designed three distinct controls that anyone could draw. So users create buttons by drawing circles, toggles by drawing rectangles, and sliders by drawing an elongated I.

A simple webcam picks up the shapes and sends them to a computer, then, a projector actually lays extra data on top of the drawing, like virtual nubs to control the sliders. This approach allows the user to draw something simple and stagnant, while light can animate additional content wherever it may be needed. The camera is able to track the user’s hands on the controls, not through fancy IR-based 3-D models, but just by sensing the color green in human skin.

And while this demo is clearly pretty basic, this principle could easily scale, adding all sorts of complex music visualizers to a user’s basic control diagram. Imagine drawing a rectangle to place an equalizer, or a square with a border to create a waveform monitor. …

The result would be a lot like the design-it-yourself Beatsurfing app, but with all the mass-approachable charm of Draw Something. It makes me realize, the iPad doesn’t need a stylus; it needs a Sharpie.

See the full story here: http://www.fastcodesign.com/1669815/this-gizmo-lets-you-draw-a-ui-on-paper-then-turns-it-into-a-touchscreen