PossessedHand hacks user's own muscles

Posted by Kate Taylor

Japanese scientists have developed a device aimed at allowing even the most cack-handed musician to play an instrument.

PossessedHand controls the user's fingers by applying an electrical current to the muscles around the forearm, using 28 electrode pads to stimulate each muscle. It does this without any conscious input from the user.

This allows the device to flex the joints between the three bones of each finger and the two bones of the thumb, and provide two wrist movements. The team says it can control the motion of 16 joints in the hand.

So far, the University of Tokyo team's tried it out using the koto, a traditional stringed instrument, and found that users were able to sense the movement of their hands that this produced, even with their eyes closed. Novice users made only four timing mistakes when using the device, compared with 13 for those who didn't.

While the device isn't powerful enough to actually make the user pluck the strings, it gives them the correct finger movements and
allowed them to play unfamiliar tunes.

Varying the stimulation level allows muscles at different depths in the forearm to be targeted. The device can automatically calibrate itself for individual users by estimating the relation between each electrode pad, stimulation level and muscle movement.

The device was developed in conjunction with Sony Computer Science Laboratories.

It's unlikely to eliminate the need for music teaching, but could lead to some interesting games, for example. Guitar Hero might just have got easier.