North Carolina State University researchers have developed technology that allows cyborg cockroaches, or biobots, to pick up sounds with small microphones and seek out the source of the sound.
The researchers have also developed technology that can be used as an "invisible fence" to keep the biobots in the disaster area.
"In a collapsed building, sound is the best way to find survivors," said Dr Alper Bozkurt, an assistant professor of electrical and computer engineering at NC State and senior author of two papers on the work.
The biobots are equipped with electronic backpacks that control the cockroach's movements. Bozkurt's research team has created two types of customised backpacks using microphones.
One type of biobot has a single microphone that can capture relatively high-resolution sound from any direction tobe wirelessly transmitted to first responders.
The second type of biobot is equipped with an array of three directional microphones to detect the direction of the sound.
The research team has also developed algorithms that analyse the sound from the microphone array to localise the source of the sound and steer the biobot in that direction.
"The goal is to use the biobots with high-resolution microphones to differentiate between sounds that matter – like people calling for help - from sounds that don't matter – like a leaking pipe," Bozkurt said.
"Once we've identified sounds that matter, we can use the biobots equipped with microphone arrays to zero in on where those sounds are coming from," he said.
Bozkurt's team also demonstrated technology that creates an invisible fence for keeping biobots in a defined area.
This is significant because it can be used to keep biobots at a disaster site, and to keep the biobots within range of each other so that they can be used as a reliable mobile wireless network.
This technology could also be used to steer biobots to light sources, so that the miniaturised solar panels on biobot backpacks can be recharged.
A paper on the microphone sensor research was presented at the IEEE Sensors 2014 conference in Valencia, Spain.