Tiny vibrations let sensors work without batteries

Tiny networking devices from Millennial Net, Cambridge, Mass., let sensors and other control appliances connect over low data-rate wireless networks, without batteries. The devices, called i-Beans, combine with Energy Harvesters from Ferro Solutions Inc., Roslindale, Mass., that generate electricity from vibrations barely noticeable to human touch. This combination lets i-Beans generate 1.2 to 3.6 mV from a 28 to 30-Hz vibration with a force of 50 to 100 mg. Applications for battery-free i-Beans include monitoring of HVAC systems through duct or machine-mounted sensors and wireless transmitters; power sensor devices in automobiles, trucks, or trains; and enable remote colonies of sensors used in aircraft and ships to detect potential problems.

"The Energy Harvester is a power source that never needs to be replaced," says Kevin O'Handley, executive vice president of business development at Ferro. "Vibrations are converted into perpetual power, giving users the benefits of a system with a long operating life," he adds.