Many times, when an emergency vehicle approaches us, we may have difficulty hearing its siren or be unable to recognize the type of car approaching us. The engineers of Harman International decided to provide a solution to the problem, developing a new sensor technology.
This is Harman’s sound and vibration sensor, which acts as the vehicle’s external “ear” by detecting frequency sounds from 20 Hz to 6 kHz. The sensor can “distinguish siren sounds through special post-processing algorithms, so it is able to decide whether the sound is a police car siren, a fire engine’s siren or an ambulance’s.”
Using, now, several external microphones to create an array, algorithms for processing the incoming sounds can be used to determine the direction from which the car with the siren is approaching. Locating is very useful when it is not possible to see the emergency vehicle because it is either behind a building or some other obstacle is in the way. Now, the optimal location to install the external microphones depends on the vehicle type, as different body type means different aerodynamics, which equates to different noise profiles.
The range of the system is up to 600 m and depends on a number of factors, such as whether the emergency vehicle is stationary or moving. Audible and other emergency vehicle alerts can be communicated to drivers through the multimedia screen that almost all new vehicles now have or the instrument panel.
The first passenger vehicle application of the validated sound and vibration sensor is expected in the US market in late 2023. Asian and European market applications will begin in 2024 or later.