Comment by zaroth | Hacker News Reader

Comment by zaroth | Hacker News Reader

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This is a great example! I hope people will take the time to click and watch it drive.

I think it’s a tough call in this case. The Tesla is trying not to block an intersection where a light is green but there’s no room to clear the intersection on the other side due to traffic ahead. In fact an oncoming car is able to turn left in front of the Tesla because it waited.

Probably the law is that you should NOT enter the intersection in such a state, but the human nature would be to make a more nuanced judgement of “how bad would it be” to continue thru and possibly get stuck sticking out into the intersection for a bit until traffic moves again.

I would think - how long might I be stuck? Would it actual impede other traffic? Also factors like, am I’m late for work? Am I frustrated because traffic has been horrible or am I enjoying a Sunday drive?

Ego (Tesla’s name for the driving software) doesn’t get impatient. It can maximally obey all traffic regulations at all times if they code it to do so, even if human drivers behind might be laying on the horn.

This little clip really shows how much nuance is involved in designing these systems, and how doing the technically right thing can either be wrong or at least ambiguously right.

LA has an unwritten law where 2-3 cars make unprotected lefts after oncoming traffic has cleared on yellow/red lights. Letting FSD drive, it can’t honor this “cultural” (technically illegal) behavior. If I am operating it, off goes FSD in that moment.

Tesla has been specifically reprimanded by NHSTA for allowing FSD to drive like human rather than to the letter of the law. The rolling stops is one I remember, but basically it'll apply to anything.

Dude it's totally following the law. You're allowed to enter the intersection for an unprotected left even if it's not clear to turn (possibly not if the end of the intersection you're going to is full of cars). If you are in the intersection, you're allowed to clear when possible regardless of the color of your light.

Most intersections with unprotected left turns let you fit at least a whole car, sometimes two in the intersection to wait, and the third car has its front wheels on the paint, so it's totally in the intersection.

While you are allowed to enter the intersection during a yellow, you are also considered legally to have been warned and would be consider liable if doing so causes an accident.

This extra liability would seem like making self driving cars error on the side of stopping to be in the interests of auto makers who would be exposed to that liability.

Incorrect. As long as your front wheels pass the stop line prior to the light turning red, you are legally driving through the intersection and should continue and clear the intersection on the other side (not stop in the middle).

Imagine how crazy the law would be if this were the case: - Light changes from green to yellow 1ms before your front wheels pass the stop line - Other direction traffic runs a red light and hits you from the side - You're now somehow liable because your wheels entered the intersection with zero ability to react quickly enough (no human can react in 1ms and no car can stop that fast) and the other driver that clearly blew a red is not?

That would be pants on head crazy, tbh...

Mostly the cars will have entered during the green, not the yellow, and were waiting for a chance to turn. When there was no opportunity to turn while the light was green, they must turn while the light is yellow or red, because they are already in the intersection and must clear the intersection.

How would entering on yellow cause an accident?

Correct. The law states that as long as your front wheels are in the intersection prior to the light turning red, you should proceed through the intersection. Inexperienced drivers that either stay in the intersection or try to reverse into traffic behind them are breaking the law and create a huge hazard for others.

Even if the light for opposing traffic turns green while the turning car is still clearing the intersection, opposing traffic is legally required to wait and not enter the intersection until opposing traffic has cleared the intersection.

It’s legal to turn left in such a case as long as you entered the intersection already. So at least the first 1-2 cars are not doing anything illegal

You can't legally enter an intersection (advance past the stopping line if present) until you are clear to perform your transit of the intersection. Left on red is never legal and marginal on yellow.

> Left on red is never legal and marginal on yellow.

Not parituclarly relevant to the gridlock violation at issue here, but left on red from a one-way street to a one-way street is legal in the same conditions as right-on-red generally in a large majority of US states, a few of which also allow left-on-red from a two-way street to a one-way street. Left-on-red is only completely illegal in a few states.

The law here is clear. There has to be "sufficient space on the other side" before you enter the intersection. There is no need to make the entire maneuver at once.

> You can't legally enter an intersection (advance past the stopping line if present) until you are clear to perform your transit of the intersection.

Yeah, I've seen tickets written for this in Emeryville, CA for cars that entered on green and weren't going to clear the intersection in the next ten minutes. (I don't know if the intersection is still that bad.) Bicycle cop, because there was no way they'd get a car in there.

> Left on red is never legal

I recall that this was legal in Michigan, where I grew up, but it either had to be onto or off of a one way street. I could never remember which, so I didn't try it.

But I did see someone make a left on red on market street in SF from the rightmost lane, which is very illegal.

> I recall that this was legal in Michigan, where I grew up, but it either had to be onto or off of a one way street. I could never remember which, so I didn't try it.

I believe it requires two one-way streets.

Yeah, this covers the case when turning left doesn't cross any oncoming lanes of traffic - so it's basically the same as turning right on red at a normal light.

Although searching for this now, it does appear to also be allowed from a two-way,[0] which sounds vaguely familiar but isn't really the same as turning right on red.

[0] https://www.michigan.gov/msp/services/traffic-safety/traffic...

Yeah, but sometimes the second and usually the third (and fourth - I have seen it!) are not in the intersection.

> The Tesla is trying not to block an intersection where a light is green

What light? There is none if you're talking about t=995.

That is not the failure. The failure is that would not move anymore and the driver had to intervene and accelerate.

At 16:55 thru 17:15? Where he manually accelerates the car and blocks the intersection?

https://youtu.be/KG4yABOlNjk?t=999

16:40 to 17:12

Seemed to be completely OK, a driver who is on the safe side would have just done this exactly

If you stay there, blocking traffic for no reason, and do not proceed when you are clear to go, as it did until the driver accelerated, you will fail a driving license exam in most countries.

Maybe it would have moved a second later...

"Most countries" would fail a driver for not crossing an intersection until there is space on the other side? I think you're being a little absurd here.

The driver in this case could see that the cars beyond the blue car were starting to move, and thus predict that he could cross a little bit early (betting on the space being available by the end of the maneuver, but risking being the ass who ends up blocking the crosswalk after miscalculating).

Here in the UK you'd be failed for blocking an intersection.

Totally, you are not supposed to block an intersection, and it is forbidden to stay on a pedestrian crossing.

Again...that was not the failure. Actually there are two failures:

- First one, to stop too far away both from the road intersection and the pedestrian crossing. And of course you should not stop on top the pedestrian crossing. The car behind the Tesla, noticed that right away, and went over the Tesla. Even the Tesla driver in the video commented on that. I wonder what FSD version that driver has :-)

- Second failure, the car ahead, the one already over the road crossing started moving but the Tesla would not move at all. Only when the video author accelerated as he mentions in the video.

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