Google Glass may be pretty much dead, but smartglasses in some form are likely to be a part of our future (whether near or distant). When that day comes you don't want just anyone picking up yours and using it without permission. Conventional passwords are one way to go, but scientists from Germany's Saarland University and University of Stuttgart have developed an alternative that doesn't involve having to memorize anything – you do, however, have to let the glasses buzz your skull.

Known as SkullConduct, the system automatically kicks in as soon as the glasses are put on. It starts by playing a broad-frequency audio signal through the glasses' existing speaker – in the case of Google Glass, that speaker utilizes bone conduction, in which sound vibrations reach the inner ear via the bones of the skull.

Because everyone's bone structure is different, however, that audio signal is changed in a unique way by each individual's skull. SkullConduct is able to detect those changes, by comparing the original signal to the altered one, which it picks up through the glasses' microphone. As long as the resulting "audio fingerprint" matches one already on file, then the glasses know that the person is allowed to use them.

Lead scientist Andreas Bulling and his team tested the technology on a group of 10 volunteers, and managed an accuracy rate of 97 percent. Those tests were conducted in an environment with no background noise, however, so one of the next steps is to try the system out in real-world conditions.

Ultimately, it is hoped that SkullConduct could also be used to verify identities on smartphones, which would have to be pressed to the side of the head while the process took place. It's hard to see, though, how pressing your phone against your face would be a step forward from today's fingerprint sensors.

A paper on the research was recently presented at the Human Factors in Computing Systems conference in California.

Source: Saarland University