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Self-Driving Cars Can Handle Neither Rain nor Sleet nor Snow

bloomberg.com

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Re: Self-Driving Cars Can Handle Neither Rain nor Sleet nor Snow

#151

Post by alkonaut »

nradov wrote: post #134
hef19898 wrote: post #123

Earlier quoted context omitted.

I'm by no means an expert for self driving cars or auto-pilots, so take it is just my personal impression. It seems that developers for self driving cars are dealing with a very different, and in some ways more difficult, environment than aircraft auto-pilots. While cars only have to deal with two dimensions instead of three and cars are still less complex machines compared to planes there are a lot more challenges.…

Dealing with failures is far more complex for aircraft. When a car gets a flat tire or suffers an engine failure the driver can just pull over and stop. But an autonomous aircraft carrying passengers or flying over populated areas would have to cope with broken sensors, uncontained engine failures, loss of cabin pressure, stuck control surfaces, etc.

Both autonomous cars and autonomous aircraft (likely) have manual backups. So the goal is to be 99% autonomous, or something like that. That works for flying because the failures are probably more far between. The planes are very well maintained, the route is clear from other planes etc. For a car, reaching 90, 95 and 99% is really difficult because of other drivers, bad weather, ice covered sensors, higher risk of mechanical failures. I agree making a 100% autonomous plane that needs to land safely in an emergency is probably more difficult for the reason you mention.

Re: Self-Driving Cars Can Handle Neither Rain nor Sleet nor Snow

#153

Post by alkonaut »

clay_the_ripper wrote: post #81

I don’t see the fact that self driving cars can’t drive in all conditions as a reason not to still want one that can drive on the freeway in good weather. A lot of people spend a large portion of their driving time on freeways so if we could solve that to a standard of safety that is acceptable, that would be a huge win in my book. As soon as it starts raining, have the system disengage and I’ll take over. It seems t…

I think it is because I assume that highway driving in good weather is a solved problem. I'm a skeptic so I also belong to those that believe that "complex" driving in bad weather is a nearly impossible problem to solve. So the interesting part of this discussion isn't "will cars have useful autonomous features?", but "will we see completely autonomous cars?". The second part is key because that is what things like autonmous taxis require.

Re: Self-Driving Cars Can Handle Neither Rain nor Sleet nor Snow

#154

Post by alkonaut »

njarboe wrote: post #30
scj wrote: post #24

Driving in dry / warm conditions is simple mechanics. Driving in snow and ice is an art. In snow and ice, variables that are typically constant or static become dynamic. Formally dynamic variables now become multi-variable equations. For example: travelling down a hill normally requires dynamically factoring for the extra speed due to the incline. Under blizzard conditions you have to factor ice/snow volume, as well…

Or most people. If it is actually blizzard conditions, one should have a very serious reason to be on the road. If not, stay at home instead of driving. Snow days are called for schools. Maybe work in general also?

I think this is very regional. I have never had a snow day in my entire life because we get snow several months per year. I think the "snow day" phenomenon happens in cities where snow is rare enough that there is no infrastructure in place to take care of it (having that would be more expensive than just accepting everything stops a couple of days per year) AND not every car has winter tyres.

After 60cm snow on one night everyone is expected to be at school and work, on time, just like any other day. It should be noted that as a driver I also expect the roads to be bare at 7am even after that kind of night, and amazingly they almost always are. At least all major roads will be, but residential streets will not. https://static-cdn.sr.se/sida/images/109/b924f65c-8cc4-4332-...

Re: Self-Driving Cars Can Handle Neither Rain nor Sleet nor Snow

#155

Post by mirimir »

rayiner wrote: post #80
mdhen wrote: post #54

Earlier quoted context omitted.

Those conditions sound like you wouldn't be driving. So, solved. Pull over and stop

LOL. In Atlanta, highway traffic just slows down to 40 in torrential downpour conditions where you can’t see lane markings.

40 mph?

On I95 in the DE-NY area, it's more like 60 mph in heavy rain. Or even in moderate snow. Everyone knows that they could never stop. But they're counting on others' inability to stop ;) But occasionally, there are massive chain-reaction pileups :(

Re: Self-Driving Cars Can Handle Neither Rain nor Sleet nor Snow

#156

Post by Animats »

The article is kind of vague. What they seem to be doing is operating a ground penetrating radar under the vehicle so that underground details can be used as positional references. This is useful only if you have a map which includes that data. At best, this tells you where you are. It tells you nothing about what's ahead.

LIDAR units that return "first and last" returns are helpful in dealing with rain and fog. The first return (nearest thing seen) will be noisy in rain, but last (most distant thing in that direction) should be stable if it's from a solid object. "First and last" is used with aerial LIDAR surveying; "first" gives you the treetops, "last" gives you the ground.

Range gated imagers for seeing through fog and dust have been available for over a decade. These are active devices which allow filtering out anything that's outside a narrow image range gate. You can adjust the gate and get images layer by layer. This technology is used by the military and seems to be somewhat restricted.[1][2][3] In addition to fog, it can show what's behind a camouflage net, objects concealed by brush, and such.

The submillimeter radar people are slowly making progress, too.[4] Automotive radars are currently running at 77GHz, which is low resolution compared to LIDAR. The resolution gets better with frequency. There are now systems in the 300GHz range.

So the sensors needed are available now, in expensive forms, and can get cheaper.

[1] http://www.dvsmil.com/PDF/Imaging_Lidar_Seeing_Through_Cloud... [2] https://www.youtube.com/watch?v=hOTo-6jXOYo [3] http://www.sensorsinc.com/applications/military/laser-range-... [4] http://consortis.eu/

Re: Self-Driving Cars Can Handle Neither Rain nor Sleet nor Snow

#157

Post by kwhitefoot »

semi-extrinsic wrote: post #118
mortehu wrote: post #64

Earlier quoted context omitted.

Yet electronic stability control[1] works far better than human control on snow, wet roads, or ice. If you don't believe it, try an obstacle course on an ice track with and without it sometime (a required part of driver's ed in Norway). Example: https://youtu.be/hd5JMQr4qe0?t=56s https://en.wikipedia.org/wiki/Electronic_stability_control

ESP works magic because it can do things that a human physically isn't allowed to do, namely "stop this one wheel from spinning faster than the others". Incidentally, if you've ever tried driving on snow/ice/mud in a 4x4 car with fully locking differentials, you have a completely mechanical solution that beats ESP. And FWIW, Swedish insurance agency research pointed out last year that cars with permanent 4x4 and ESP…

That made interesting reading. It would have been even more interesting if they had also divided the population of cars by the drivers sex and age. At least here in Norway it is very much the case that accidents are more frequent and more severe when a young man is driving. Also I suspect that women on average are more likely to drive a two wheel drive car. My point is that we might find that four wheel drive cars driven by women are as safe or safer than two wheel drive cars driven by women and that the worsening of safety for four wheel drive driven by young men is even more dramatic than the study showed.

Re: Self-Driving Cars Can Handle Neither Rain nor Sleet nor Snow

#158

Post by MortenK »

throwaway76543 wrote: post #150
Retra wrote: post #131

Earlier quoted context omitted.

Yes, it is trivial to calculate how to respond to known hazards. What is hard to calculate is what the hazards actually are in any given situation. Humans don't merely look at the road and compute how much standing water is there, they have prior experiences and a sense of what other drivers are doing on the road and why they are doing those things.

Self driving cars also have prior experiences and a sense of what other drivers are doing and why. That's sort of the point of machine learning. In fact, they will have a lot more prior experience than any human driver in the world.

Unfortunately in the realm of machine learning, quantity does not equate quality.

Re: Self-Driving Cars Can Handle Neither Rain nor Sleet nor Snow

#159

Post by killjoywashere »

MortenK wrote: post #158
throwaway76543 wrote: post #150

Earlier quoted context omitted.

Self driving cars also have prior experiences and a sense of what other drivers are doing and why. That's sort of the point of machine learning. In fact, they will have a lot more prior experience than any human driver in the world.

Unfortunately in the realm of machine learning, quantity does not equate quality.

The parent of any teenage driver can also attest to this.

Re: Self-Driving Cars Can Handle Neither Rain nor Sleet nor Snow

#160

Post by treerock »

village-idiot wrote: post #146
realandreskytt wrote: post #145

Earlier quoted context omitted.

I’d recommend visiting Finland. In these parts, there’s basically 3 months of optimal visibility. The rest is fog, rain, snow, sleet and road conditions that would shut down most of US. Yet people drive and do so safely. “What people can do” is a bit different from “what an average us driver can be expected to do”

Doesn’t findland have a higher vehicle fatality rate than other nations?

Seems to be less than half the US rate.

https://en.wikipedia.org/wiki/List_of_countries_by_traffic-r...

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