Hacker News Reader

Comment by oldgradstudent | Hacker News Reader

Can it actually distinguish reliably between an overnight truck and a manhole cover, an overpass, and an overhead sign? These are far more common occurrences.

Reportedly it can't.

https://www.wired.com/story/tesla-autopilot-why-crash-radar/

View on HN

No, but I mean all cars for some time now have to include anti-collision radar as standard, it doesn't use cameras to recognize anything, it just goes "you're approaching a stationary object without slowing down - SLAM BRAKES". I'm guessing what's happening here is that Tesla is aware that it's approaching a stationary object, but the camera system overrides it because it doesn't recognize it as a danger. So in a way, a much simpler system would have prevented this accident,.

You can do that, but what level of false positives are you willing to accept?

How often are willing to have your car perform an emergency stop for an overhead sign? How safe is it to have your car brake aggressively in a middle of the highway for nothing?

I don't know why you keep mentioning the overhead signs? The anti-collision radars that are mandated in every new car are mounted on the bonnet level, they won't react to an overhead sign. And yeah, emergency braking in the middle of the highway is not safe at all, but seeing as literally all new cars have to have that system and we're not seeing people randomly braking in the middle of the motorway for no reason I can only guess it's fine. Besides, the system doesn't start braking if you're actively applying throttle, it will start beeping at you but it doesn't start braking until you lift your foot off the gas.

> but seeing as literally all new cars have to have that system and we're not seeing people randomly braking in the middle of the motorway for no reason I can only guess it's fine.

But we definitely do.

https://www.cbsnews.com/news/automatic-emergency-braking-in-...

The price we pay for having relatively few false positives is a high false negative rate. For example, a Tesla won't stop for an overturned truck or the pedestrian standing next to it.

Because overhead signs were mentioned as one of common sources of radar false positives during the reporting about the 2016 Tesla crash.

>No, but I mean all cars for some time now have to include anti-collision radar as standard,

The way these work is by tracking other moving objects around you rather than stationary objects you are approaching.

It'll track another car to see if it emergency brakes or changes lane too close to you, but it won't track a parked car on the road that you side swipe or head into etc.

The Subaru’s camera system definitely tracks stationary objects, and it’s obnoxiously sensitive. The vehicle throws a beeping tantrum when approaching steep hills or roundabouts at any speed above a crawl. It will auto-brake for a birthday balloon in the road. Pretty sure this overturned truck would set it off.

Reply on news.ycombinator.com