Hacker News Reader

Comment by userbinator | Hacker News Reader

The important part is that it got rear-ended while waiting to merge --- I suspect a strong factor in this was the fact that the car behind it was expecting it to go and merge, but it suddenly stopped instead.

Even for a human, merging into flowing traffic is tricky and one of the more difficult maneuvers; combine that with a (not obviously?) self-driving car that doesn't behave quite like human drivers expect, and I can see how this could happen.

If I saw a clearly-marked "autonomous test vehicle" I'd probably stay far away from it, but I suspect this one wasn't. Imagine the surprise of the human driver who thought the car in front that he hit was just driven by another idiot...

View on HN

Looks like it happened here: https://goo.gl/maps/RHiVTRSuDJ62

Pretty short merge lane, more of a surface street than a highway. Probably not atypical for a car to stop to wait for an opening to merge.

Lawrence Expressway is terrible. I frequently see cars stopped at these "merge lanes".

But that’s what you’re supposed to do here, right? There’s a yield sign.

You're not supposed to stop at a yield sign if there isn't traffic preventing you from merging. That's why it's a yield sign, not a stop sign.

Since the report mentions Apple's car was moving slowly (~1mph) when it got hit, I suspect what could've happened is it may have just released the brakes and was about to accelerate into the merge, meaning the car coming from behind would see both a clear path in front of it and its brake lights off.

There's a comment here about the car behind following too closely, but if you look at regular traffic and your own driving behaviour, you'll find that you subconsciously monitor and anticipate the behaviour of the cars around you --- meaning that almost everyone is technically "following too closely" to expect the car in front to suddenly and rapidly brake to a complete halt. Self-driving cars are far less predictable in that sense. If you come up behind a car in a merge lane with its brake lights off and no traffic obstructing it, you would not expect it to be slowing down or even stopped, because your past knowledge has taught you that a car in this condition is almost certainly going to be accelerating.

Computer controlled cars should have some sign or way of easily telling that they are computer controlled. Maybe if this was true, too many people would fuck with them, unlike those cars that say "student driver". Maybe the sign should say "student driver" when it is controlled by a computer. Definitely a true statement at with the current tech

People often fuck with student drivers too. Eg aggressively trying to overtake because they don’t want to be behind a learner. Although I suppose this is a different sort of fucking with than the kind you mean.

One could hope that the number of always recording cameras and other sensors on auto-auto would deter most of the jerks.

> You're not supposed to stop at a yield sign if there isn't traffic preventing you from merging. That's why it's a yield sign, not a stop sign.

That's what I meant; you're supposed to stop if there's oncoming traffic. That's what I assume the car was programmed to do. I have no idea what the other car was doing or what it was thinking–there's always the chance that it was someone who was distracted.

That’s a decent length (there’s more behind the camera) with a yield at the start of it. It’s basically an acceleration ramp, lengthened probably due to the speed of expressway. Stopping after the yield sign shouldn’t be happening for either autonomous vehicle or human driver; although it happens.

I admit the camera perspective can be misleading, but it looks like what, 4-5 car lengths? If traffic is heavy it’s not enough space to accelerate up to the speed of passing cars.

If traffic gets heavy, I can easily see the need to stop and wait for an opening.

I’ve been on that ramp, and it wasn’t too bad. Usually the speed of traffic isn’t that high due to the stoplight just before it, and people usually just wait at the yield until it turns red.

If traffic gets heavy, drivers should wait at the yield until it is safe or until the light turns as the sibling poster suggests.

I often get on to Lawrence at this particular intersection, using this merge lane. The traffic you're merging in to can be going at 50 MPH in the right lane with about one car length separation between cars. A human merging here has their head craned back, watching for a gap to appear, and accelerates to merge in to the gap. Who knows what exactly happened here, but this one is a particularly tricky merge under traffic.

I feel like Santa Clara county has a bunch of these dangerous merging lanes.

This is a common scenario for human-on-human crashes too. The second person in line starts scanning the oncoming traffic early, assumes the first driver has gone, and accelerates into them.

I was rearended in this same situation as well, seems like a common error in human drivers too.

Human drivers are fucking awful. I don’t understand why everybody here is assuming that the self-driving car must have done something strange to cause this.

This, but also, human drivers do similarly awful things like stop at the end of a long acceleration on-ramp when they should have been accelerating to match the speed of traffic they are attempting to merge into.

It's biased because all commenters are human drivers who think they can handle that kind of situation. We often don't realise how much risk we take on every day while at the wheel.

What percent of drivers are involved in a collision while merging? I imagine it's miniscule. Rarely deadly.

I banged up my mum's car doing exactly this the first year I got my license. Was a little nervous and in a hurry, saw an opening and went for it. Car in front of me did not see the same opening. Bang.

It’s also something I would expect self-driving cars to have a huge advantage over human drivers, simply because the former can check behind and to the side while still checking the car in front of them.

I wonder if it would be more useful if these cars had more lights than normal cars (yellow, green, etc.), so that they could signal their intentions before they act.

When autonomous vehicles register problematic situations, they do tend to be unusually cautious, right? But so do some people, so hey. And when you get rear ended, you're rarely at fault. Because the other driver was obviously following too closely.

> And when you get rear ended, you're rarely at fault.

It was my understanding that in California, it is (legally) _always_ the rear-ender who is at fault, and not the rear-endee.

It can happen after a sudden lane change where the person that’s rear ended is at fault.

My impression was that was the way most if not all states were set up.

Ummm, that's what I said :)

"The rear-ender is always at fault no matter what" is largely myth. The truth is just that historically it's been very hard to prove you weren't at fault if you hit someone else in the rear. Now, with dashcams becoming more common and people becoming more aware of deliberate-crash scams and road-raging "brake check" incidents, that's starting to change.

It’s pretty obvious when you see them - they’re covered in hardware.

That hardware doesn’t signal to other drivers.

Reply on news.ycombinator.com