How does an autonomous vehicle circumnavigate a closed road?

pete6032

Diamond Member
Dec 3, 2010
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How can driverless car navigate around a detour? Say for example a road was closed and that information was not known to the car. The car goes to turn on the road but sees construction or road closed signs in the way so it cannot turn. The GPS must recalculate a route somehow, but how does it do that if the car does not know for what distance the road is closed? What would prevent the GPS from trying to go down 1 block and turn onto the road, multiple times over and over until the closed road was no longer closed?
 

Jaepheth

Platinum Member
Apr 29, 2006
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It drives up, up, down, down, left, right, left, right.

I think you can, in theory, adapt a maze solution. That is, turn left at the detour and then take every available right afterward; essentially sticking to the "right wall" until you're back on the intended path, found your destination, or arrived back where you started in which case there is no solution.
 

Humpy

Diamond Member
Mar 3, 2011
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Once one driverless car figures it out it will tell the rest which route to take.

I guess this is different than a truly autonomous vehicle though.
 
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zinfamous

No Lifer
Jul 12, 2006
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Anyway, I imagine the best way for this to work for now would be for detour notifications and routes to be blasted out on RF signals (or whatever has an appropriate range) at the approaching site of the detour. Maybe add some signal nodes to the DoT workcrew trucks so these can be installed near or on the detour signs.

....of course, it would take precisely 1 day before wacky teenagers! figure out how to hack them and screw with the routes (like sending all auto pizza delivery cars to their house--or their enemy's house) or just steal them altogether.
 

pete6032

Diamond Member
Dec 3, 2010
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It drives up, up, down, down, left, right, left, right.

I think you can, in theory, adapt a maze solution. That is, turn left at the detour and then take every available right afterward; essentially sticking to the "right wall" until you're back on the intended path, found your destination, or arrived back where you started in which case there is no solution.
The maze solution though would be incredibly inefficient. What if the street was closed for 50 blocks, then the car would make 49 attempts at circumnavigating the closed road before it actually made it back onto the road. A rider would not put up with that in real life.
 

OverVolt

Lifer
Aug 31, 2002
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It doesn't. The google autonomous car goes 25mph and must have the route pre-mapped.

If someone closed a lane on the highway for an accident at 55mph you'd all die. Just saying.

Autonomous cars are a joke actually.
 

Ruptga

Lifer
Aug 3, 2006
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How does a human do it? It will probably just assume that entire street is closed and use a route that doesn't involve it at all.
 

OverVolt

Lifer
Aug 31, 2002
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I'd love to see an autonomous car get a doctor to work on a snowy highway with accidents and lane closures just saying.
 

NoTine42

Golden Member
Sep 30, 2013
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Every time I ask for GPS driving directions from my home, I get a route that goes through a ravine (too steep to walk down without grabbing trees) instead of going down my driveway.
 

Matthiasa

Diamond Member
May 4, 2009
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I'd love to see an autonomous car get a doctor to work on a snowy highway with accidents and lane closures just saying.
With a non autonomous car he still wouldn't... You are putting way to much faith in the driving ability of the average individual.
 

OverVolt

Lifer
Aug 31, 2002
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With a non autonomous car he still wouldn't... You are putting way to much faith in the driving ability of the average individual.
Nah stick some snow tires on an AWD and you are good to go. Snow tires often have zig-zag sipes in several directions so that even if you slip a little in odd directions you can maintain control. I'd love to see a google car adapt to changing handling characteristics, tires, weather, and lane closures simultaneously. I'd love to see a google car run a red light in a blizzard to prevent an accident.
 

shabby

Diamond Member
Oct 9, 1999
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How can driverless car navigate around a detour?
Simple... it doesn't. There are many situations where an autonomous car won't know what to do because that specific scenario wasn't programmed into it, its not an ai, it simply does what it's programmed to. Truck flipped and blocked traffic both ways... it'll just sit there the whole day until you take the wheel and go around the truck on the side.
 

pete6032

Diamond Member
Dec 3, 2010
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So then if they cannot circumnavigate an unexpected lane closure than how will they operate in the city of Pittsburgh, which just approved them yesterday?
 

zinfamous

No Lifer
Jul 12, 2006
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It doesn't. The google autonomous car goes 25mph and must have the route pre-mapped.

If someone closed a lane on the highway for an accident at 55mph you'd all die. Just saying.

Autonomous cars are a joke actually.

lol. you're such a joke.

no vision. the future is going to be a very unhappy place for you. :D
 

OverVolt

Lifer
Aug 31, 2002
14,278
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So then if they cannot circumnavigate an unexpected lane closure than how will they operate in the city of Pittsburgh, which just approved them yesterday?
With a team of engineers and computer scientists in a manual car behind it. Then they all write reports how awesome the autonomous car runs.
 

OverVolt

Lifer
Aug 31, 2002
14,278
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lol. you're such a joke.

no vision. the future is going to be a very unhappy place for you. :D
You're assuming everything stays the same. Imagine what a job it is at the very fringes of our road network to keep updating it for every new housing development, red light, new road, etc. On the same token you have to take out the under-used non-repaired roads.

A quick google check says there are 4.12 million miles of center-line roads in the US. The whole usefulness of roads is their simplicity. Only in big cities do you have bright markings and well-engineered intersections that are great for being interpreted by a computer but I would love to see one drive from mainland US to Alaska in a night time rain storm.

Its basically impossible for autonomous cars to cover 100% of the road network and if there is anything other than 100% autonomous cars on the road a mixture of manual and autonomous cars is a clusterduck.

You're one of the many people who will "Get what they wished for" and will wish you hadn't.
 

zinfamous

No Lifer
Jul 12, 2006
111,987
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Nah stick some snow tires on an AWD and you are good to go. Snow tires often have zig-zag sipes in several directions so that even if you slip a little in odd directions you can maintain control. I'd love to see a google car adapt to changing handling characteristics, tires, weather, and lane closures simultaneously. I'd love to see a google car run a red light in a blizzard to prevent an accident.

the difference is the google car is programmed--can be programmed--to understand the situation and react in a statistically appropriate manner. Every single time. It does this far better than a human wood, because humans are fundamentally stupid, in aggregate, when it comes to this type of decision making. The google car would actually run the red light far more successfully in a comparable number of times than a collection of random dumbass humans would. And you know it. Have you been driving long enough to familiarize yourself with road humans?

If you actually knew what you were talking about, you would know that the only reason traffic exists is because people are driving--not because of the number of people, not because of cars, not because of traffic lights. It is because of people and their idiotic selfish tendencies. The only reason accidents happen is because of people. End of story.

Now, in the current paradigm, half robot cars and half people cars is a difficult situation. In the very near future where all cars in urban areas and commuter zones are completely automated, every car is part of every other car. Every situation is known miles in advance. Your vain attempts to understand that reality from the broken understanding of how humans can react to situations only as they happen simply doesn't reflect the reality of the automated commuting future that is coming.
 

zinfamous

No Lifer
Jul 12, 2006
111,987
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You're assuming everything stays the same. Imagine what a job it is at the very fringes of our road network to keep updating it for every new housing development, red light, new road, etc. On the same token you have to take out the under-used non-repaired roads.

A quick google check says there are 4.12 million miles of center-line roads in the US. The whole usefulness of roads is their simplicity. Only in big cities do you have bright markings and well-engineered intersections that are great for being interpreted by a computer but I would love to see one drive from mainland US to Alaska in a night time rain storm.

Its basically impossible for autonomous cars to cover 100% of the road network and if there is anything other than 100% autonomous cars on the road a mixture of manual and autonomous cars is a clusterduck.

You're one of the many people who will "Get what they wished for" and will wish you hadn't.

I agree with some of this. Obviously, mixing autonomous cars with stupid humans is going to be difficult. The only reason these cars will wreck or cause accidents is because of human drivers acting stupidly. But of course, it will only ever be the fault of an autonomous car. Add of course we will continue to ignore the 300k deaths per year from human drivers and the very first human that dies in an autonomous car will somehow be alarming and national news.

The best place for fully autonomous zones is urban city centers and commuter zones. Once people can appreciate a life with zero traffic and far less stress, you will start to see suburban life adapt and, I imagine, less car ownership (so even less crap on the streets), as more people--probably one or two generations that haven't even been born yet--that see greater value in on-demand car service for everything they need a car for.

As for the rest of your argument, which is basically, "It's too hard, let's not do it!" This is the USA, son. We don't puss out just because something is "too hard." :D

A fully automated system wouldn't even need the roads that you claim need to be updated. Most major commuter expressways, in the most populated metro systems, could probably get away with 2 lanes in each direction--maybe 3 at the most--with cars that react to real density rather than stupid humans that rubberneck and text their way down the freeway. We get to reclaim space

All you really have to do is look at how a massive colony of ants work and travel together with a centrally networked communication system. These are actual natural models that inform the research in this kind of AI and automation networks
 
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OverVolt

Lifer
Aug 31, 2002
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I don't think that is 100% true. Most traffic in Baltimore for example is due to the limited number of roads entering/exiting the city. To go from one town to the city there is literally only one on-ramp that is efficient. Like 10,000 people need to use that ramp in the morning. Traffic flow problems are caused by the poor highway design. When you are leaving the city everyone will need to get into the left lane and make a left off Lombard street at some point for example. And the light timing is actually on dummy timers. So thinking that autonomous cars are going to fix something that should've been upgraded in 1950 is a joke. On the other end of the spectrum in rural areas autonomous cars are a joke as well. There is no traffic where I am now. Its a big deal if a town has -a- traffic light.
 

Capt Caveman

Lifer
Jan 30, 2005
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Car see's road closed sign, recalculates new directions and gets to destination. Not that difficult.
 

quikah

Diamond Member
Apr 7, 2003
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Now, in the current paradigm, half robot cars and half people cars is a difficult situation. In the very near future where all cars in urban areas and commuter zones are completely automated, every car is part of every other car. Every situation is known miles in advance. Your vain attempts to understand that reality from the broken understanding of how humans can react to situations only as they happen simply doesn't reflect the reality of the automated commuting future that is coming.

Very near future? HAH! Who is going to pay for that? I can walk out of my door and see a 20 year old car on the street right now. It will take 20+ years to get all the cars changed ONCE they become viable (which is another 10+ years).

Overvolt is right. The current Google self driving cars are road boulders. I get stuck behind them on a daily basis, I wish they would ban them from the streets (street has a 35 MPH limit, but they can only go 25. FU Google). They do nothing but cause traffic congestion.