This Spray Can Turn Any Surface Into A Touch Screen

      Tired of pesky small touch pads? Well, this spray might be your savior, allowing a wide variety of surfaces to become touch sensitive.

      The technology, called Electrick, was developed by scientists from Carnegie Mellon University in Pennsylvania, with the findings published in an open access paper.

      The spray consists of an electrically conductive carbon-based material. When applied to an object, it allows it to conduct electricity. By applying electrodes to the object, and then measuring the voltage at different points, the position of a person’s finger can be tracked.

      "For the first time, we've been able to take a can of spray paint and put a touch screen on almost anything," said Chris Harrison, assistant professor in the Human-Computer Interaction Institute (HCII) and head of the Future Interfaces Group at CMU, in a statement.

      The spray can be applied to a variety of objects, anything from plastic toys to smartphone cases, and even to Jell-O. 

      For example, applying the spray or paint to a table, you could have certain locations that are touch sensitive to open apps on your computer. A toy could be made to make noises when you touch its nose or belly. And a brain-shaped piece of Jell-O can be used to teach people about the various regions of the brain.

      The effect is known as shunting, where electric current is “shunted” to the ground when a finger touches a particular location. The electrodes can localize where this shunting is occurring, using a process known as electric field tomography.

      In their paper, the researchers note that modern touch screen technology is not suited to large applications, such as a table or desk. Using Electrick, however, things as large as a wall can be made touch sensitive, with a tap of a finger turning a light on or off for example.

      The team also said their process is compatible with regular manufacturing methods, such as spray coating or casting, and even 3D printing. This means there is a huge range of objects that can be made touch sensitive, with little additional technology required.

      The team also found no wear in any of the objects they made, with some used up to 896 times by participants. They note, however, that they’re not sure how the coating will hold up to elements like rain, and environmental electromagnetic noise from other appliances affected the accuracy. Nonetheless, it’s a good start for a cool idea.