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Hidden obstacles for self driving cars

technologyreview.com

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Re: Hidden obstacles for self driving cars

#31

Post by balloot »

I've been saying this for years, as I took Thrun's class when he was at Stanford. Google's dirty little secret is that self driving cars are still mostly smoke and mirrors. Given relatively controlled conditions and a trained driver who can play backup when needed, they work. But if you put them in complicated situations - snow, a busy city environment, abnormal signage - watch out.

The problem is that the driving model is probabilistic. When you solve a problem probabilistically, getting from 90% covered to 99% to 99.9% covered to 99.99% covered involves exponential leaps in difficulty. So even if the car covers 99.9% of driving conditions (and it currently doesn't), there's still a tremendous amount of work to be done to get it to 99.9999% correct, or whatever the threshold is for it to be deemed "safe" for fully autonomous use.

I personally am bearish on the technology, as getting the inconvenient final situational cases correct will be extremely challenging. I would love to be proven wrong, but at Stanford I came to the opinion that the probabilistic approach would get us to really cool demos, but never a fully autonomous vehicle. That being said, the people working on this are a whole lot smarter than I, and I would love to be proven wrong.

Re: Hidden obstacles for self driving cars

#32

Post by bagels »

balloot wrote: post #31

I've been saying this for years, as I took Thrun's class when he was at Stanford. Google's dirty little secret is that self driving cars are still mostly smoke and mirrors. Given relatively controlled conditions and a trained driver who can play backup when needed, they work. But if you put them in complicated situations - snow, a busy city environment, abnormal signage - watch out. The problem is that the driving mo…

One that Google has not solved, for instance, is navigating a gas station. When they fill up gas at Shoreline & Middlefield in Mountain View, I see humans doing the driving.

Re: Hidden obstacles for self driving cars

#33

Post by webignition »

letstryagain wrote: post #17
thewarrior wrote: post #15

I am making a bold prediction that it will be decades before a self driving car can drive itself safely on Indian streets. Road Signs ? None. Rules ? They're more like suggestions. Roads ? What Road ?

They just have to be significantly safer than humans, and that's not hard.

I think you would have to experience first-hand what it is like to drive in almost any country that is outside the US, Europe or most of the commonwealth to really appreciate the difficulty of developing a self-driving car that could handle such conditions more safely than humans.

It very much is hard.

I've driven in and around India. Aside from the fact that the majority of vehicles have four wheels and generally move forwards more often than backwards, the similarities to driving in countries with more regulated driving environments are few to none.

Try circumnavigating Connaught Place on any day for a taster, or try taking the main highway north from New Delhi any distance.

The smaller more fragile vehicles give way, in the interests of self-preservation, to the larger, heavier vehicles.

Approaching in an intersection in a truck? Blast your horn to warn others of your approach so that they can get out of the way. Slowing down to carefully approach the junction is not what happens.

Need to cut across some lanes of traffic in a school bus to make a turn? Have your co-pilot hang out of the side door waving, shouting and berating other vehicles to make them give way. That's your turning indicator in many cases.

Need to take the same school bus on a circuit to collect kids in the morning and are running a bit late? Why not head straight through some empty fields. Roads can be optional.

All of the above I have experienced first-hand.

Re: Hidden obstacles for self driving cars

#34

Post by balloot »

Swizec wrote: post #24
naiyt wrote: post #8

I remember a few of these difficulties being mentioned in Sebastian Thrun's Self-Driving Cars course on Udacity. It's been awhile, but I seem to remember the snow discussion in particular. The problem wasn't just slippery conditions, but the question of how the vehicle can localize itself when the various visual cues that it uses are covered in snow (e.g. road lines). Pretty interesting stuff.

People have trouble with snow as well. If there are no tracks in front of you, you just guess where you're supposed to go and go for it. It's pretty fun on roads you know well, rather miserable on roads you don't. Also, most 3-lane roads magically turn into 2-lane roads, and many 2-lane roads turn into 3-lane roads etc.

You just described the problem nicely. The "magic" that turns 3 lane roads into 2 lanes etc, is a situational awareness that is really, really difficult to impart on a learning system. The big problem is that probabilistic models don't have a notion of "common sense" solution to an odd situation. They need to have seen the situation, or something very similar to it, enough to make a reasonable calculation of what to do.

Re: Hidden obstacles for self driving cars

#36

Post by gamerDude »

Most of the problems yet to be tackled seem to be troublesome for many humans as well. But as for the adding to the maps, couldn't google work with local governments to have stoplights, stopsigns, construction etc added and google will contribute observations of potholes etc.

Re: Hidden obstacles for self driving cars

#37

Post by goalo »

teej wrote: post #7

I made this comment about google self driving cars two years ago and I think it's still relevant now: 200k miles is nothing. Over 8 billion vehicle miles are spent per DAY in the US. One person is killed for every 75 million miles driven. 200k miles isn't enough to test every terrain, under every weather condition, in every lighting, etc. There's too many variables in the equation. The Google car won't be truly safe…

totally right. They should also stop logging the miles they did going around in circles in a controlled environment too.

Re: Hidden obstacles for self driving cars

#39

Post by balloot »

prbuckley wrote: post #12

It seems to me we have a better chance of seeing low flying autonomous vehicles for personal transportation before we see self driving cars (think quad coptor drone style vehicle with 500 lb payload capability). Autopilot systems are already widely used in commercial air vehicles. Fewer obstacles need to be accounted for in the air and there is less in grained regulation. It feels like we are going to leapfrog the ca…

I'm with you here. You could essentially build from scratch a traffic setup for autonomous vehicles, instead of retrofitting the autonomous vehicles to a current driving system. And by flying you get to avoid lots of complications that will prove very difficult to work around. No pedestrians, snow, signage, construction, etc etc.

Re: Hidden obstacles for self driving cars

#40

Post by jbarham »

There was recently a car crash here in Victoria, Australia, that resulted in the deaths of two teenagers and injuries to five others. It was apparently caused by the relatively inexperienced driver swerving to avoid a rabbit. In hindsight it would have been better if the driver hadn't swerved and the rabbit had been run over, but in some sense this is a moral choice of the type that robots can't make.

In theory self driving cars sound like they could be potentially safer than human drivers, but there are many edge cases like the one above where a robotic driver following reasonable heuristics (e.g., swerve to avoid animals on the road) could cause fatal accidents that most human drivers would be able to avoid.

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