The conductive spray paint is called Electrick. As reported by the MIT Technology Review, it was developed by researchers at Carnegie Mellon University who sought to let regular objects act as computer input devices. The substance has already been tested on materials including plastic and silicone. It’s less effective on porous materials where the paint tends to run off.
Conductive spray paint itself isn’t anything new. Sprays are often used to reduce the electromagnetic interference experienced by household gadgets. The team wanted to find a way to use the conductivity of the paint to work out where a user is pressing, essentially creating a touchpad.
Electrodes were attached to the edge of each object being sprayed. These were then linked together using sensor boards and wired up to a laptop for analysis. When you touch the surface, you disturb the field created by the electrodes and conductive paint. The change can be measured on the sensor board and converted into an input signal for the computer.
“Electrick is a low-cost and versatile sensing technique that enables touch input on a wide variety of objects and surfaces, whether small or large, flat or irregular,” said Yang Zhang, lead researcher on the paper. “This is achieved by using electric field tomography in concert with an electrically conductive material, which can be easily and cheaply added to objects and surfaces.”
The technology still has a long way to go before it’ll be ready for commercialisation. It can currently track motion to within a centimetre and recognises touches with 99 percent accuracy.
The team hasn’t yet determined whether the material itself can be affected by electromagnetic interface though, a problem which could spell the end for the project. There are also lingering questions around the durability of the substance. If it wears off quickly, its applications will be limited.
Demonstrations of the current version of the tech show how it could be used in vehicles to detect gestures on the steering vehicle. Other potential applications developed by the team include wall-mounted control surfaces, a touch-controlled guitar and a jelly “brain” that can work out where it’s being felt and poked. If developed further, the spray could add another dimension to digital interactions, restoring physical feeling to the senses experienced while using devices.
Electrick will be most useful when added to objects that already benefit from touch-sensitive areas. Manufacturers will be able to convert the entire surface into a giant touchpad, ideal for remote controls for smart home devices. This is the kind of tech the first release version of Electrick will target.
The researchers are now commencing work on an upgraded version of the spray that could be a better candidate for commercialisation next year. The next-generation form of Electrick will feature a smaller sensor board and a simplified setup routine, enabling it to be integrated into more objects. Performance and accuracy will also be improved, bringing touch-sensitive desks and doors a step closer to reality.
