Scientists working on developing a real-life sonic screwdriver

We don't quite have psychic paper yet, but Doctor Who's other coolest prop could be coming to reality. A British scientist with the charming name of Professor Drinkwater is attempting to create an actual sonic screwdriver.

According to a press release from Bristol University, Professor of Ultrasonics Bruce Drinkwater is doing experiments to try and create a sonic screwdriver in real life:

The technology is already being trialled in modern manufacturing to fix parts together and ultrasonic force fields are being developed within the medical field to separate diseased cells from healthy cells. Professor Drinkwater and The Big Bang team are now exploring whether super powerful versions of these sound beams could bring Doctor Who's iconic device to life. ...

Engineers are looking into how ultrasonic waves can be spun at high speed to create a twisting force similar to that of a miniature tornado, which could undo screws remotely. They have also experimented with rotating ultrasonic force fields which would act like the head of a real screwdriver.

Once they've got it up and running, how long before they can miniaturize the technology enough to fit in your pocket? Seriously, how long? [Bristol University]