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Comment by Afforess | Hacker News Reader

Normal humans also run red lights when the yellow-to-red light time is too short. Transit guidelines generally state that yellow lights should stay lit 1 second for every 10mph of the speed limit. When the yellow light is shorter than this, it's easy to get caught in the middle of a red.

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Have you seen the video? It's way more jacked up than what you're implying:

https://m.youtube.com/watch?v=pzzQ42D9Srw

Watch that and tell me that it's reasonable or caused by a short yellow...

I saw his reply as adding "too short of yellow to red time" to the list of "not paying attention" and "being an asshole" for human reasons to run red lights. I'm not sure why you're attacking him for a claim he didn't appear to make.

I don't think this was an attack; rather, an example furthering the case of "too short".

Holy cow.

With a pedestrian in / on the edge of the crosswalk. And there was even another car that had been moving just a few seconds earlier stopped there too...

You don't think it was going to stop if the pedestrian stepped out in front? If autonomous cars can't do that, they can't do anything.

Who knows? This Volvo didn't: https://www.youtube.com/watch?v=AsTxS6tg6xc

It's not an autonomous car and that particular car doesn't even have "pedestrian detection system" installed. It only can detect big objects like cars without optional hardware.

It's driverless. Are you sure that Uber had a pedestrian detection system?

I've run that light myself by accident. It's a hard light for humans too. This light is in the middle of a block rather than at the end. The area is full of activity including people walking but also popular sights. That brick building to the right is SFMOMA. Its hard to notice the traffic lights amongst all this activity not to mention that you don't look for it. Also that middle lane can easily have its views obstructed on both sides.

That area is also messed up because you need to be in the correct lane else you will be forced up different streets so you have many cars trying to change lanes. Lastly, that area has its share of asshole drivers that cut you off, speed, etc....

From my perspective, that car is behaving like someone not aware of the light and not sensitive to context (should have driven more slowly). You can call that asshole behavior if you wish.

Its hard to notice the traffic lights amongst all this activity not to mention that you don't look for it.

That makes it hard for a person, especially if they're new to that road, but why would it affect the database lookup that a self-driving car is doing?

I barely know anything about how self driving cars work so someone else should answer that. I am not affiliated with Uber or its competitors.

Perhaps I should have said that its a hard light for humans but that I don't know anything about how hard it is for cars.

The standard approach to detecting signal lights is to have a database of GPS positions of the signals, along with rough location in the camera where the signal is expected to occur [1]. Then, when the car nears the signal, it locates the signal and detects the current color.

This mechanism really shouldn't be susceptible to the same biases as humans. The described signal may legitimately be more challenging for the self driving car, but more than likely the signal was missing from Uber's database. Their lack of explanation for this failure does not inspire confidence in their approach.

[1] http://www.cs.cmu.edu/afs/cs.cmu.edu/Web/People/zkolter/pubs...

>but why would it affect the database lookup that a self-driving car is doing?

Who said a self driving car is doing a "database lookup"?

If anything, a good self driving car should NOT do any kind of database lookup (of the location of traffic lights etc) and be able to recognize and respond to a moved, impromptu (e.g. because of road work), new, unfamiliar, etc. traffic light.

Getting additional data from a predefined map is expected, even if it's just for something to test the data coming from the sensors. If the car knows there's a traffic light on the map but it isn't 'seeing' one then it should be handing control back to the human, not just carrying on regardless on the assumption that the map is wrong.

A level 5 self-driving car would work completely autonomously without any prior knowledge of the area it's driving in. We're not there yet.

I see -- checked the paper. I knew they were using maps data for the routes and assistance (and that would extend to traffic lights) but I'd expect them to be able to spot all kinds of movable traffic lights (e.g. when there are works or an accident) by pure image recognition/AI.

Honestly I thought it was the vehicle just before it, until that one came out of nowhere on the right. That was WAAAAAY after. I nearly closed the browser tab before it came through.

Looks like it didn't consider a traffic light in the middle of a block as a thing that could happen.

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