Watch the iPhone’s accelerometer pick up keystrokes from an invisible keyboard (Video)

A student at Goldsmiths, University of London has apparently been able to create an invisible, virtual keyboard for iPhones by using the device’s built-in accelerometer to pick up vibrations caused by tapping or typing on a surrounding surface area. As you can see from the video demonstration above, the “Virbrative” software developed by Florian Kraeutli (on a jailbroken iPhone 4) allows him to measure the strength and frequency of vibrations and then map them to iOS’ onscreen keyboard. The Telegraph spoke with Kraeutli about the software developed for a project on user interfaces:

“The signals I’m collecting are very weak,” said Florian Kraeutli, a computing student at Goldsmiths, who created the system as part of his work on user interfaces.“At the moment it’s more of a proof of concept but if you made the accelerometer more sensitive you could improve the accuracy quite easily.”

In the video above, we see the developer use a keyboard drawn on a piece of paper to train the system before tapping directly on the table underneath. Kraeutli noted users would ideally “train each key, but you can do just a couple.” According The Telegraph, the system “determines the intended key correctly about 80 per cent of the time, so the data is also fed into an auto correct dictionary to ensure the words are spelled correctly.” Kraeutli suggested that access to more powerful accelerometers could allow him to increase the accuracy of the system:

He suggested that accelerometers in smartphones may be set to be less sensitive than they are capable of to conserve battery power. The system is currently more accurate on smaller surfaces, which vibrate more with each tap.