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Comment by maxerickson | Hacker News Reader

Detroit doesn't really get enough snow or stay cold enough for ice to be an extended problem. On a cold morning intersections can get a bit slick, but that is about it. (I've lived in Ann Arbor, my brother lives a bit outside Detroit).

Michigan also tends to just salt the shit out of roads. Probably enough to impact the chemistry of the Flint River. Not so much way up North where it stays colder. Sand there.

As far as the cars, they just measure the available traction several thousand times a second. Electronic stability control is mandatory for new cars in many jurisdictions: https://en.wikipedia.org/wiki/Electronic_stability_control#R...

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The cars certainly don’t measure the traction, not even once per second. You need wheel slip to do that, and constant wheel slip is not a good driving mode. Not to mention the difference between static and dynamic friction. At most cars can collect the lower bound of friction coefficient when braking/accelerating and lower/upper bounds when wheels are slipping. If you have a straight stretch of road, and no cars tried to brake/accelerate on that, the only friction data you would have is ‘no wheel slip at .02g acceleration/deceleration’. It doesn’t help the AI predict its braking distance for an emergency braking maneuver when driving that stretch of road, so a conservative AI would be forced to keep a much larger headway than a typical (or even cautious) human.

Have you been here long? We call it a “Michigan winter” for a reason. Yes, Detroit suffers less for a few reasons, but I still wouldn’t agree with your assertion.

It doesn’t sound like you’re describing the Detroit I grew up in, where dozen+ car pileups are a regular occurrence, particularly the big hundred+ ones on 94 out your way. That’s even discounting the wide-area ice storms that knock out power from everything getting coated in three to four inches of pure ice, which I can remember happening at least four or five times when I was younger. The last couple winters have been relatively light. We are due for a whopper.

Seriously, Michigan winter is accelerated natural selection for drivers. You learn quick or you die.

I live in Detroit. Here's a picture of the front of a truck. https://iainmait.land/img/photos/1920/ram_grill_2016_iain_ma...

Ah, I thought Detroit would be colder than that mid-winter.

As for traction on ice, if the vehicle is already on the ice, it’s too late to slow down. I wonder how the cars could know when they are coming up to ice. Humans can rarely know, but have some complicated ways of identifying, I think from glossiness? And ice is much more rare than snow/slush but both can be present side by side. Either way, I think they will figure it out. Sand can be awful to clean up in urban areas when too muh is used.

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