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by heynk 2314 days ago
When I was starting my engineering career, it was right around when the first DARPA challenges had started. The hype was beginning, and my optimism towards technology was strong. I thought the predictions and timelines would be correct, and I still feel strongly that self-driving will be safer than humans in the long term.

Recently, I bought a newer Subaru, with EyeSight. It has adaptive cruise and lane keep assist. The LKA is fine - it'll beep if you sway outside of a lane, and automatically adjusts the steering, but it won't keep you centered. It's more of a safety thing, and it works well from that perspective.

The adaptive cruise is really good. It's camera based, and I have had zero problems with it. It works well at night and in pouring rain. It'll even stay pretty close to the car ahead of you if you turn the "tolerance" all the way down. I'm always impressed.

Since I've had this car, I've thought a lot more about the practical implementation details of actual self-driving. I more often notice situations when driving that are seriously complex.

The more I think about it while I'm driving, the more I realize how fucking hard self-driving would be.

8 comments

I tried out a relative's Subaru on a 6h drive over the holidays. I really liked the adaptive cruise control for following behind folks who were not keeping a consistent speed. I just set it to a reasonable value at the maximum following distance and stopped worrying about my speedometer.

However, at one point the guy in front of me turned off onto a small side road. It was at night, and I don't think the car realized he had moved into a turn-off lane. It slammed on the brakes. I probably went from 90kph to 40kph before it realized I was not going to hit that car.

I completely failed to react to the situation. I was worried my erratic braking would cause an accident behind me, but in the moment, I didn't know how to stop it. That was not a type of emergency I had considered or prepared for.

Yeah this is interesting. My Tesla M3 does similar behavior, and so I often am ready to punch the accelerator. In the Tesla, this is how you solve that problem. The driver's push on the accelerator contraindicates the AI's decision to slow down, and so the car follows the driver's direction.

Where it gets dicey is the scenario where the "imminent collision" (hazards on, seatbelts tightened) detection is triggered, and the driver continues to push hard on the accelerator. Tesla has a fairly lengthy statement in the manual about this scenario. The bottom line is there are all kinds of heuristics at play that may or may not result in an override depending on the specific sequence of events.

I'm amazed by people like you. You're a programmer, you know how your code looks like. Worse still, you have seen other people's code, how they fail to account for corner cases, you've seen so many articles on HN's front page about security bugs found by fuzzing. Yet, you trust your LIFE to "heuristics"? Do you really trust that when the proverbial black swan flies in front of your car the software won't swerve you into the oncoming traffic?

Why don't you just drive yourself or take a taxi?

The "collision imminent" scenario would occur whether or not the car is in self-driving. If the car manages to avoid a collision that is the amazing part to me. And there's plenty of evidence that the Teslas do, in fact, avoid quite a lot of collisions. It would be foolish, however, to drive like it's going to resolve all your collisions for you.

I view these as assistance to driving. It's a comfort that the steering and brakes are not overridable. And honestly, if the system messes up so badly as to go flying into a barrier, well, that's not so different from a tire popping, another car careening across into yours, or other catastrophic and unlikely events that do happen. We have seatbelts, crumple zones, airbags, pre-tensioners, cargo hold-downs, and emergency services to help us survive what even 40 years ago would be unsurvivable accidents.

If the car avoids 99% of crashes, but crashes happen 1% of the time, and it causes crashes 1% of the time, then it's making you less safe.

Those are just arbitrary numbers and a simplistic framework, but the point is, you can have a huge increase in safety by the numbers, and a very small increase in problems due to the safety system that cancel it out, because the prior underlying rate of crashes was pretty small.

I think this is an abstract pattern that comes up in other contexts and it doesn't seem to be intuitive.

True, the implementation quality does matter.
Especially in a second world country like the US where semis dont have skirts and you do have crossroads without lights on highways

https://arstechnica.com/cars/2020/02/i-was-just-shaking-new-...

Same thing, first time I used the Subaru EyeSight system. Now I know to pay attention for that particular failure mode, and override with the gas pedal and a little steering.

Definitely surprised the heck out of me though the first time the car slowed way down on the interstate because the car ahead of me pulled onto the off-ramp.

I see the current Tesla system in similar light, it does very well in every day common situations and some of what it does is damn good; driving down country roads with curves and such is exhilarating but still safe.

Now currently the Tesla system does give you a much more clear idea of what the car does see around it but still no option to see what it fully records; there are means to get this footage but its not something every driver can.

Now my TM3 goes in at the end of the month for the hardware 3.0 upgrade which will allow it to process more of what it sees and also relay that to me. The difference in what other's have show in just what the car relays back to the driver exposes just how much information has to be processed.

Then comes the simple fact, the real issue is that the hard decisions are ones we make all day, driving by exception. We make so many choices that are exceptions to the rule we are numb to it, it is nearly subconscious.

Then the other issue, other drivers. Not just people who drive badly but those who will go out of their way to cause self driving cars issues. with the number of people on the road you will find them with too much regularity. More might pop up if regulation comes down which demands self driving cars or semi autonomous cars obey all traffic laws, especially speed limits. On some roads I drive just obeying the limit is enough to impart rage on other drivers.

I'm inclined that improving systems up to full autonomy for many highways in many weather conditions is a fairly realistic maybe 5-10 year plan. Which would actually be pretty nice and potentially a big win for safety.

The problem with widespread L4/5 is that you need to get to a car that can literally drive itself between 2 points on a map with a high degree of reliability, in a wide range of weather conditions, on roads of varying conditions, with unexpected/unmapped obstacles that may require doing something technically illegal to get around, without human help. And that, as you say, seems really hard.

Ultimately, the right place for most carmakers to focus on at this point would be situational awareness and safety features, gradually improving the situations where the car can prevent a crash.

Put it this way: If a driverless car would be safer than human drivers, then that would imply that all the necessary technology would already exist to allow humans to be the driver while the car still keeps them out of deadly situations. If such tech is not possible to develop, then it seems unlikely that true driverless tech (which would need to combine that safety tech with a lot of other technology) will happen.

Earlier today I was driving on the highway with autopilot (I have a Model 3) and came to a section where the road is angled in such a way and the pavement is old enough that there is a fair amount of standing water. Driving manually, I steer to the right or left slightly to avoid the ruts filled with an inch or two of standing water. Autopilot, on the other hand, was perfectly happy to blast right through it.

That's the kind of weird edge case that makes me think we're farther from real self-driving than most people want to admit. I'd be hard pressed to define exactly how I'd tell the computer to avoid that. Maybe the answer is that it can't deal with that until it results in hydroplaning, and then it reacts however it can.

That's a particularly insidious circumstance since standing water can conceal hazards from any vision system these cars or humans have. I would expect self-driving cars to refuse to drive through water in any circumstance. There could be a large pothole in the puddle that would ruin your car.

Worse than a mere car-destroying pothole, what if the flooded portion of the road no longer existed at all? That's a common enough occurrence that student drivers are generally warned about it specifically, warned to never drive across flooded sections of roadways because your car might fall into 10 feet of water without warning. If a self-driving car doesn't avoid a scenario we teach teenagers to be wary of, I don't think it deserves to be called self-driving.

I guess no one on my dead end street will be getting a self driving car then. There's a low spot near the main road that causes a large puddle all the way across the street whenever it rains.

There's a few other places in town that often flood, including one on a main road that doesn't really have any alternative route. There's also a section of the road along the coast where high surf sometimes hits the sea wall and splashes up and over it on to the street. It's quite a sight, but I wonder what a self driving car would make of _that_.

You have local information that cars don't yet know (but they probably will someday -- cars can send detailed road conditions to a central database, or they can communicate with other cars, so the car in front of you can say "watch out, there's a big pothole 8 inches from the left lane line" and your car will try to avoid it.

What do human drivers do there when they are unfamiliar with the road? Seems like the auto pilot should be able to do at least no worse than human drivers.

> What do human drivers do there when they are unfamiliar with the road?

I assume the same as me -- I avoid water-filled ruts whether I'm familiar with a particular road or not.

It may well get advanced enough some day to pick up the difference between wet pavement and water rut, and car-to-car communication could potentially help, but that's a level of technology improvement that feels considerably farther away than just a few years.

>Recently, I bought a newer Subaru, with EyeSight. It has adaptive cruise and lane keep assist. The LKA is fine - it'll beep if you sway outside of a lane, and automatically adjusts the steering, but it won't keep you centered. It's more of a safety thing, and it works well from that perspective.

I have 2020 Subaru and it has lane centering on top of that. On the highway, with clear lane markings it comes very close to driving itself. It won't slow down to handle curves on its on though.

Today saying cars have "self driving capabilities" is like saying you're fluent in 3 words of a language. They have advanced driver assists but the insistence on the "self driving" terminology tricks enthusiasts and less tech savvy people alike into a false sense of confidence in the tech. Sometimes all the way to their deaths.
the majority of the miles I drive are highway so for me "3 words" covers a large percentage of my usage. This is likely true of most people as well.
Indeed. The only way to call today's cars "self driving" is to narrow down the conditions of driving to the point where it's just as ridiculous as my "3 words" example, and then realize they're still not narrow enough.

> the majority of the miles

The "miles" metric that's not very relevant, not all miles are created equal. Driving in a straight line with almost zero challenges is nothing like driving as a whole. Would a power supply that's only able to take idle loads (majority of the time) be considered any good? How about a phone that can only make calls only most of the day?

Even a "dumb" car can be considered self driving by this definition. All you need is cruise control or if you want to get fancy, ACC and LKA. This would allow you to drive for hours on end or hundreds of Km on a highway with little (fractions of a second at a time, maybe a total of 1Km with hands on wheel) or no human intervention.

> Would a power supply that's only able to take idle loads (majority of the time) be considered any good? How about a phone that can only make calls only most of the day?

When the models without those downsides require constant strong attention and nearly unbroken eyesight? Yes, sell me those models now. I'll switch between manual mode and somewhat-limited-feature mode when necessary.

You may have missed the point and there’s not much room to dumb it down. If you have to narrow the definition of driving so much then it’s not actually driving.

Many cars spend a lot of time idling, especially in crowded cities. Would you call them self driving because they can perform unattended this very, very narrow task (but long) from the whole activity of driving?

As for the “yes sign me up” I call bluff. There are plenty of situations in daily life where you need to have constant supervision. You wouldn’t let your child operate in them under the assumption that “there’s a good chance they won’t die”. You will take the constant supervision in place of the device that only works for 1% of the features you need and even then it might kill.

Take an iron that can iron by itself but only small, cotton clothes, and once in a while it burns down the house. Do you leave it unattended? Do you even call it self ironing?

That's a great analogy! For English (and autonomy levels), this works for orders of magnitude: Two and two and two and two and two, no good; ten times ten, good in easy things; with a thousand words, you can get things done and sound normal; a vocabulary of ten thousand words provides an adequate command of the language to discuss complex concepts; 10^5 or any higher exponent comprises capability exceeding that of a majority of users.

I do agree that we're still at level 2: it's relatively amazing (i.e. see what can be done with the limited toolset available), but not really that great: outside of predictable, menial tasks, the rough edges become acutely limiting.

Except nothing existing today is fully autonomous (i.e. I can kick back and read a book) even on just highways.
> The adaptive cruise is really good. It's camera based, and I have had zero problems with it. It works well at night and in pouring rain. It'll even stay pretty close to the car ahead of you if you turn the "tolerance" all the way down. I'm always impressed.

I checked, assuming it's actually using a radar - and you're right. They seem to use a stereo camera system. Neat.

https://www.subaru.com/engineering/eyesight.html

I'm surprised it works well in bad weather, but I've never tried it.

It's not impervious to bad weather, but pretty resilient. I'd say in the 2 years we've had ours the system has shut off maybe 3-4 times due to one of: a) very low and direct sun angle, b) very heavy rain, c) dense fog. Which, to be fair, are all difficult conditions for a human to drive in as well.

But I agree with the parent, the suite of driver assistance features is very good, but a long way from "self driving".

you haven't had a issue with it. multiple people died already.