When firefighters search for survivors in a burning building, they’re in danger of getting lost themselves. With sips of breathable air choked out by smoke, and next to no visibility, some of the worst disasters in history have created deadly labyrinths that claimed the lives of those who bravely go in.
A new device could prevent these situations from happening. A team of technologists at Sweden’s KTH Royal Institute of Technology has created a sensor system to be placed in the heels of firefighters’ boots. The scientists say the system is one of the first to not only track the steps and direction of the firefighters in a building, but also integrate a radio network to communicate those movements to the full firefighting team.
“The point here is that these systems must work where we have no GPS coverage,” explains Peter Händel, professor of signal processing at KTH. “The sensors in the shoe, they are so-called inertial sensors, accelerometers and gyroscopes, and they measure the forces of the acceleration and rotation. And with this information, we can actually capture the movement of the step.”
Radio-based sensors on the firefighter’s shoulder automatically send the data from the firefighter’s boot heel to the team outside, as well as measure the distance among different firefighters in the building. Where GPS fails, the Swedish sensor system can also track firefighters as far as 82 feet underground.
“If we are blindfolded, and we start somewhere, we can actually sense how we move, and this is basically how these foot-mounted sensors work,” Händel says.
The team tested their device for the first time in October, when they equipped firefighters with the tool in simulated conditions. Händel and his colleagues are currently writing up the results of this experiment, while further pushing the boundaries of their research.
Eventually, the team would like to put better quality sensors in the soles of shoes, maybe for mass production. (Händel suggests the elderly could benefit from shoes that track falls.) Royal Institute scientists are also working with technologists in Kampur, India, to develop energy-harvesting tools from the kinetic energy of firefighters’ steps.
“On the sensor side, there’s been a lot of development for some time now, mainly driven by the cellular phone industry,” Händel says. “The challenge is that the sensor technology is evolving so fast, but also they are also getting smaller, cheaper, and also they get worse performance in general. So basically what we have to do then is enhance the quality.”