> Can we just fast forward to the future where EVs glide around silently and people look both ways before crossing the road?
Getting rid of 50% of your car detecting senses doesn't seem like a good idea
Getting rid of 50% of your car detecting senses doesn't seem like a good idea
When vehicles past a certain volume (which are not aggressively streamlined to shatter human-powered landspeed records) move faster than 25 kph (15 mph) they displace enough air that they are quite loud.
An automobile-sized vehicle isn’t some kind of terrestrial ninja when its engine doesn’t make noise. Depending on make, model and speed, the volume of displaced air is significantly louder than the engine running at constant velocity.
That said, the "cars make noise go vroom" argument hasn't really worked for decades now. Modern mufflers mean most unmodified cars aren't loud enough to be clearly heard over background noise in an area with lots of cars. Pedestrian safety is absolutely a problem that's worsening, but I don't think that "make cars noisier" is the solution.
Barring the ideal (to me) solution of fewer cars in the first place, what seems most promising to me is making the infrastructure itself more pedestrian-friendly. I was impressed to see what Amsterdam's city center did with encouraging cars out onto the thoroughfares and out of the places where people are walking. They didn't seem to have the same "Waze addicts blowing through stop signs on residential streets" problem that we have in North America. Nor did they have the same problem with stroads and their obnoxious traffic patterns that set everyone who uses the on edge. It seemed to make transportation both safer and more pleasant for everyone involved.
Tires often make more noise than car engines nowadays. I live along a busy street and often I can't audibly distinct a Tesla from an ICE except for a faint hum. They are both as loud when passing by.
There's a significant gap between theory and reality, but I'm not sure noise pollution is the answer.
It might not even require GPS or anything complicated; just respond to car’s radar squawks, so that it can measure the distance and relative speed from the delay and Doppler shift. You’d need to use frequency that bounces around nicely, to “get around” other cars blocking the line of sight. We can’t do that with passive pedestrians, because we can’t tell the echo from pedestrian from the (also moving, like other cars) background. This could work more reliably and at much higher distances.
Of course someone must have tested that already; I’d be grateful for a link :-)