In many parts of the country pulling over and making room for an approaching emergency vehicle with its lights and sirens on is the law, but that’s assuming you can hear or see it coming, which isn’t always easy when you’re behind the wheel. A new device promises to not only listen for emergency vehicles, but also let a driver know which way it’s coming.
Carmakers work hard to block as much outside noise as possible from entering a vehicle, whether to provide a quieter more peaceful ride, to make car stereos sound better, or to facilitate our ever-growing reliance on voice-activated assistants. It’s not necessarily a bad thing, but that soundproofing can make it hard for a driver to hear hazards like an approaching emergency vehicle and get out of the way in time, or even the sounds of kids approaching.
To compensate, researchers at the Fraunhofer Institute for Digital Media Technology IDMT in Oldenburg, Germany, have developed a device that looks like the compact cellular antennas you see perched atop many vehicles now. But instead of improving wireless connectivity, the device contains a collection of sensitive microphones pointing in all directions. The audio picked up by these microphones is routed inside the vehicle where a control unit, hidden away with all of the car’s other electronics, strips away the unwanted background noise and identifies individual sounds happening all around the vehicle using machine learning techniques also developed at the Fraunhofer institute.
But instead of just identifying sounds like a firetruck’s siren, the system also uses custom beamforming algorithms that denote the intensity of the sounds across the microphone array. This allows the location of the source of the sound to be determined, and even a trajectory calculated with just a few seconds worth of sampling, so that a driver could be alerted to what direction an emergency vehicle is approaching, and how long it will take for it to get near.
The system could be beneficial for more than just alerting drivers to approaching hazards, however. The sounds of children playing could indicate a school is nearby, and that a driver should reduce their speed accordingly. It could also listen to physical problems with the vehicle that aren’t necessarily heard on the inside, like weird sounds coming from the engine, or a repetitive tick-tick-tick indicating that a nail or other object has become lodged in a tire. In the event of an accident the sensitive microphones could even be used to listen to the sounds of victims calling for help, and automatically contact emergency services with details about the number of people potentially involved. And let’s not forget about all the road-ragers who would appreciate a heads up on which vehicle just honked at them—or maybe that’s not the most productive use of this tech.