Ladies and Gentlemen, the marvelous future has officially arrived! It is now possible to touch a sprayed on sensor on the wall to turn on the light and even change its brightness or play music by touching notes painted onto the side of a building. Anything is possible thanks to the collaborative work of researchers from the Computer Science and Artificial Intelligence Laboratory (CSAIL) at MIT, University of Bath, and the University of Bristol. They’ve developed spray-on sensors that can turn any surface – no matter the shape, size, or texture – into an interface to control electronics. It even works in wet outdoor settings!

The technology is called Sprayable User Interfaces. It is a combination of layers that together are as thin as paint but can recognize touch and turn things on or off and more. For instance, you can even apply this onto the armrest of a couch so that you can flip through channels on the TV by merely brushing the armrest to the left or right. The layers consist of an underlying conductive copper ink layer that’s able to recognize touch, a microcontroller that connects to the ink and reacts to it, and a top design layer of airbrushed color. You can connect any gadget to a stenciled design applied to any surface.

The researchers write in their paper:
Unlike many existing techniques, such as 3D printing, screen printing or inkjet printing, spraying is not bound to a specific volume and, as often demonstrated by graffiti artwork, can create output that covers entire walls and even building facades. Our work contributes to the vision of blending digital user interfaces with the physical environment and extends it to large-scale interactive surfaces.
The technology is relatively straightforward, even though the system does require some advanced planning and design. Stencils have to be drawn out and made, and special care has to be placed in making sure the conductive ink is accurately arranged on the surface.
Maybe the best part is, it’s all airbrushed on, so the user interface elements can be any design you want. There are no dimensional or technical constraints, such as the size of a printer dictating the size of the sensor.

Unfortunately, it’s still not ready to be scaled up and commercialized. It may be a while before you can turn your TV on by sitting on the couch. But don’t be surprised when you see airbrushed designs that can respond to your touch on smart buildings shortly!
