The system, Electrick, is described by the team as "using electric field tomography in concert with an electrically conductive material, which can be easily and cheaply added to objects and surfaces."
The touchscreen display on a smartphone is equipped with a small electrical charge disrupted every time a user's finger touches it. By detecting where a loss of charge on the screen has occurred, a smartphone can figure out where it's been touched.
The scientists at the University's Human-Computer Interaction Institute took a similar approach to the experimental technology. In practice, the innovation covers an object — such as a guitar — in a conductive coating. Electrodes are then placed around the edge of the item, allowing Electrick to detect changes in the electric current when and where a finger makes contact with the surface.
While not as accurate as other touch input devices, Electrick is already capable of detecting the location of a finger's touch to one centimeter, sufficient for using any surface as a button, slider or other control. Subsequent development will undoubtedly improve precision yet further.
There have been numerous attempts to expand the size of touch screens, but the technology has hitherto proved too expensive to scale to large surfaces, or irregular shapes. Some mooted alternatives have employed lazers and cameras, but the touch connection is broken if either is blocked.
While a visually arresting invention, the spray is no gimmick — it means the touchscreen of any device needn't be flat (or, indeed, small) — if individuals were so minded, they would be able to transform anything into a giant touchscreen.
Researchers on the project used Electrick to add touch sensing to surfaces such as a large drywall, a steering wheel, and jelly.
While smartphone screens are likely to remain in their current, highly functional and familiar state, the team's efforts do mean that any and every surface can become a touchscreen — and that any and every surface can be modified to respond to direction in the same way a mobile device does.
The team said the spray was resistant to erosion, and can even be protected with a spray coating or sheeting. It is also compatible with all modern manufacturing methods, such as spray coating, vacuum forming and casting/molding — and 3D printing.
