Friday, July 28, 2006

Beyond the Pedometer

A two-part kit lets some Nike shoes talk to Apple iPods. Will it spur a range of consumer applications for wireless sensors?

By Kate Greene

This kit features a wireless sensor in the insole that gathers data about your workout and sends it to an iPod. (Credit: Wade Roush)

Nike and Apple Computer recently unveiled a joint product: the Nike+iPod Sport Kit, which uses a wireless sensor to monitor pace, distance, time, and calories burned while walking or running. Some experts believe the Sport Kit is the forerunner to wireless, personal sensors with myriad functions, from tracking locations to monitoring biometrics.

The Sport Kit turns iPod Nanos and specialized Nike shoes into a feedback system that continuously measures workout activity and updates a user's progress. The kit contains just two pieces: a receiver that attaches to an iPod Nano (it's not compatible with other iPods) and a thumb-sized sensor that slips into a slot under the insole. The sensor monitors physical activity and transmits the data wirelessly to the receiver, which then sends it to the iPod, where it's stored.

The data is wirelessly sent over the same radio frequency used for Wi-Fi and Bluetooth (2.4 gigahertz), using a proprietary wireless technology. It's powered by a battery that Apple says has a lifetime of 1,000 hours -- long enough to outlast the running shoe if the sensor is put in sleep mode when not in use.

Other technical details of the sensor are unclear; Apple declined to answer such questions. But according to John Huggins, executive director at the Berkeley Sensor & Actuator Center at the University of California at Berkeley, the sensor most likely contains a simple accelerometer, similar to those used to deploy airbags in cars, that measures the acceleration of a foot during running or walking. It could also contain, he says, a small amount of memory, logic circuitry, and a transceiver that sends and receives wireless signals.

Gadgets that give workout feedback aren't new, of course. Walkers, joggers, and runners have long been using pedometers to count their steps and wrist watches that monitor their heart rates. The kit goes a step further, though, by hooking up with the iPod, already a popular consumer product. In addition, the data from it can be uploaded to a website (nikeplus.com), so users can monitor their progress and set new fitness goals. In this way, the gadget provides a platformto keep track of workouts.