As we get closer to the widespread deployment of autonomous vehicles, there’s still discussions about what sensors will be required to make these vehicles safe – for the passengers and other pedestrians and vehicles. Those discussions usually revolve around cameras, radar, LiDAR (Light Distance and Ranging), and ultrasonic. There’s one other sensor that isn’t discussed – an audio microphone.

https://www.forbes.com/sites/tiriasresearch/2018/07/31/how-will-autonomous-cars-respond-to-emergency-vehicles/#3255636f27ef