Engineers are racing to develop indoor navigation systems that can track firefighters to within a meter or two. Some are close to succeeding. IEEE Spectrum reports.
Creating a system for navigating indoors -- where satellite signals don't easily penetrate -- is tough. And consumer products requiring Wi-Fi signals are useless if the power source goes up in flames.
Now, if two groups can clear just a few lingering technical hurdles, they may be able to get equipment in the hands of firefighters, paramedics, and other first responders within the next couple of years.
A U.S. Department of Homeland Security team is working on a gadget that uses gyroscopes and accelerometers to track a wearer’s movements in three dimensions. It’s called Geospatial Location Accountability and Navigation System for Emergency Responders (GLANSER).
- Units the size of tissue boxes attach to firefighters' breathing gear.
- Each device packages a military inertial measurement unit (IMU) with a GPS receiver, Doppler radars to correct velocity, a pressure sensor to judge changes in altitude, and a radio to measure the range to a fixed base station and to other nearby units.
- Before a firefighter enters a building, the initial position is established and a radio beams position changes to the commander.
- Neighboring wearable units communicate with the base station and with one another, forming a "mesh network," letting them swap location data and relay weak signals.
- But the components of a portable unit alone add up to $3,000, not counting the fancy battery.
Researchers from the Worcester Polytechnic Institute are working on their Precision Personnel Locator (PPL).
- Firefighters carry portable units the size of walkie-talkies with a 24-hour battery life and contain a cheap IMU (broadcasts internal position) and a radio transmitter (beams ranging signals).
- Three stationary radio transceivers link wirelessly to one another and to a laptop-size base station that houses an atomic clock and orients itself and the transceivers using GPS.
- Transceivers (antennas mounted on trucks or ladders) listen for transmissions from firefighters and pass those signals to the base station.
- Timing the signals’ arrival from each portable radio helps determine their ranges and calculates their three-dimensional positions.
- Location data are streamed wirelessly to the commander, who dictates an escape route or directs rescuers over voice radios.
- To make it mass-producible and cost a few hundred dollars, the team is eliminating expensive, power-hungry hardware by building better software.
This post was originally published on Smartplanet.com