You're probably familiar with haptics even if you haven't heard the term. Haptics are systems that create a touch feedback as part of a computer interface. A simple example is the vibrating motor in most smartphones. The motor spins a weight, creating a vibration in the phone. This can alert you to incoming messages or augment experiences such as games or other applications.
Today, scientists are looking to create new haptic interfaces. One of those is SkinHaptics, a system that scientists at the University of Sussex developed with funding from the European Research Council and the Nokia Research Centre. The cool thing about SkinHaptics is it doesn't use any vibrating parts to create the touch feedback sensation. It uses sound.
Specifically, SkinHaptics uses ultrasonic frequencies with time-reversal processing, which sounds like something out of a science fiction film. What it means is that an ultrasonic emitter can send sound waves from the back of your hand through your flesh to create haptic feedback on your palm. To you, it would feel as if something is touching or vibrating on the palm of your hand, even though the device would be on the back of your hand.
Why would you want something like this? It could be part of a larger system. Imagine that you're riding a bike or driving a car outfitted with sensors wirelessly connected to the SkinHaptics device. These sensors can detect objects from any direction, not just the one you're looking at. If the sensors pick up something that could pose as a hazard to you, you could get an alert on your hands, perhaps even in such a way to indicate the direction of the incoming threat. It'd be like you have Spider-Man's Spidey-sense!
Another application involves turning your hand into a touchscreen. A projector could create a display on your hand. As you interact with the display, the ultrasonic emitter could create haptic feedback to enhance the experience. And because you don't need to have a surface in physical contact with your palm to create a haptic sensation, there's nothing to block the projection against your hand.
It's possible that in the future we won't be carrying around smartphones. It'll be our hands that become smart technology — and you'll be able to feel it.