杏吧原创

A tap on the arm switches music tracks while you run

Accelerometers embedded in a pair of wristbands pick up vibrations that are used to control an MP3 player
Can't stop to change track
Can鈥檛 stop to change track
(Image: Matthew Leete/Getty)

FUMBLING in your pocket to play with your iPod can ruin your concentration while running. Now you won鈥檛 even have to break stride to change a track with a device that allows users to control and toggle through a play list without even touching their iPod.

The unnamed device, which Japanese firm NEC hopes will go on sale within the next couple of years, is composed of two black sports wristbands, each embedded with an acceleration sensor, which detects movement. The sensors use Bluetooth to transmit data on the position of your hands, for example, to your iPod or MP3 player, pre-loaded with NEC鈥檚 software.

The wristbands are able to create five 鈥渂uttons鈥 out of the user鈥檚 hands and arms. Clapping hands is registered by the software as 鈥減lay鈥 or 鈥渟top鈥. A tap on the lower left arm means 鈥渘ext鈥 track, while a tap on the upper left arm is 鈥減revious鈥 track. The right arm acts as the volume control. Tapping the lower right arm signals volume-down, tapping the upper right arm is volume-up.

鈥淭he wristbands can create five 鈥榖uttons鈥 out of the user鈥檚 hands and arms. A clap means 鈥榩lay鈥 or 鈥榮top鈥欌

Lead researcher Shin Norieda, says that the sensors can tell where the user is tapping by how attenuated the signal is 鈥 the further up the arm the tap takes place, the weaker the signal reaching the sensor. Data from the acceleration sensor tells the software which arm is moving and which arm is receiving the tap and also whether it is a sharp one. Norieda claims normal running movements will not be confused with taps. 鈥淚f you tap something, the waves form a sharp peak,鈥 he says. 鈥淲e filter out the shorter wave patterns to avoid confusion.鈥

Each sensor also carries a positive charge on the outer side and a negative charge on the inside of the wrist. The software detects when the two negative charges are brought close together as you clap and switches between 鈥減lay鈥 and 鈥渟top鈥.

Hiroshi Tanaka, professor of engineering at the Kanagawa Institute of Technology in Atsugi, Japan, said that 鈥渁 certain amount of calibration may be needed for each user of the device鈥 as each individual taps in a different way.

NEC also hopes to sell the technology to commuters to control music on crowded trains where it can be hard to free your arms. NEC researchers presented the technology at last month鈥檚 Tokyo鈥檚 Interaction 2011 conference.

Topics: Fitness / Music