I know I'm a bit late to the party, but I thought I'd add two cents to rectify potential misconceptions stated above:
and
Zarathustra has the gist of why the sounds are necessary, but maybe not why ICU sounds specifically are preferred. The purpose for replicating ICU sounds is so that visually impaired people (including people who are blind) can maintain independence and mobility while being able to avoid recognizable hazards via auditory cues. People with visual impairments are trained to listen for approaching vehicles when deciding whether it is safe to cross a street. Bicycles are a potential threat and are difficult to detect by those with visual impairments because they're relatively silent, but they, along with EVs, are a small percentage of total vehicle hazards. And bicyclists are able to more nimbly avoid collision since they are lighter and travel at comparatively lower speeds than motor vehicles. EVs have greater mass and travel at higher speeds - they are not as capable at collision avoidance.
The implication that pedestrians who step in front of a moving vehicle are simply idiots is a grossly false assertion. Yes, some people may be careless, preoccupied, or otherwise willfully unaware, but there are others who do not have sufficient visual acuity (or auditory capability - but that's a different conversation) that the majority of the population takes for granted while independently navigating through or around potential hazards. Crossing the street is an extremely dangerous activity for a visually impaired person - especially when crossing in a high noise environment - and so to reduce risk of collision, when EVs are able to replicate familiar ICU sounds, they reduce the cognitive processing required for determining whether or when it is safe to cross.
If you're curious and are interested in conducting an insightful exercise, try the following with a friend:
- go to a busy intersection in your area - one that is without built-in auditory crossing signals for the visually impaired
- wear a blindfold - your friend should not wear a blindfold so they can be the control case and can help keep you safe
- try to determine whether or when it is safe to cross the street
- right or wrong, reflect on how difficult that decision would be without your friend present