Nowadays, even an ordinary car offers a seatbelt and an airbag to protect you from the physical impacts of a crash. A smart car, on the other hand, pledges to avoid the impact at its best. Integrating all these specs, the new Mercedes-Benz comes with another novel feature to protect you from the deafening noise of the collision as well.
This new feature is one of the smartest moves by Mercedes. The current version of Mercedes’ E-Class sedans will provide the ears with a layer of audio protection using ‘pink noise.’ The pink noise is a burst of sound, that will cause a muscle inside the ear to contract thus, cushioning the eardrum against the crash noise which could potentially deafen the victim.
Even though Mercedes is the first to introduce such a feature, pre-crash protection technology is not new. Some cars tighten the seat belt minimizing forward motion or inflate an airbag on the sides to shield against side impact.
The pink noise is a broad spectrum of frequencies. When the car senses an imminent crash; the pink noise fills the cabin triggering the acoustic reflex. It causes the stapedius muscle to contract. The stapedius is the smallest muscle in the human body, the contraction of which braces the bones of the inner ear and the ear drum.
The stapedius reflex is naturally triggered due to loud noises, but the threshold is 100 dB which is quite damaging for the ears. The sound of a crash is around 145 dB, enough to impair hearing at least temporarily. Even the deployment of the airbag produces a noise of about 165 dB. According to an estimate, this noise causes a partial, but permanent hearing loss to about 17 percent of people.
Unlike a single-toned sound, the pink noise is spread across a broad spectrum which enables it to trigger the acoustic reflex despite being low in volume. The test of the system found that an 80 dB burst of pink noise is enough to trigger the reflex. Thus, it prepares the ears for an impending crash.
The technology sounds quite unusual, but it did not come out of the blue. It started with the idea which was patented in 1997 by Armin Kausch who was the employee of TRW Automotive. The work for the tech dates back to 1960.
The tech is implemented only in E-Class sedans of 2017. However, Mercedes is preparing to add the same feature to other cars as well. The company has spent quite some time in perfecting the feature, but we can not be sure of how effective it is until Mercedes collects some crash data from the E-Class.
What are your thoughts on the introduction of the Pink Noise feature? Comment below!