3D printing allows us to make a wide variety of shapes, but adding interactive features generally means somehow strapping various electronics to them. The AirTouch project, however, presents an alternative option by enabling a fabricated object to sense up to a dozen different touch points with no components or complex calibration necessary. 

Instead compressed air is pumped into the 3D-printed item, which escapes via up to 12 tiny holes. As each hole is touched, a barometric sensor picks up the pressure response, which is then interpreted by an Arduino Uno board as user input. 

The system has been tested on a variety of interactive figures, from a model rabbit to a bar graph. A short demo can be seen below, while the project’s research paper is found here.