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What is going to stop someone from putting up a sign on the side of a highway that looks like a photo of a red light? Very cheap to deploy and extremely dangero

What is going to stop someone from putting up a sign on the side of a highway that looks like a photo of a red light? Very cheap to deploy and extremely dangerous. I remember seeing a post on HN (but I can’t find it) where simply flashing such a photo for ~100ms was enough to get cars to come to a sudden stop

jiofih 6y ago
What stops someone doing that today? Humans are also vulnerable.
- conradev 6y ago
  Humans would be able to see that it is on a long stretch of straight road with no intersection in sight and so while they might be confused, they would not come to a sudden and instant stop. The paper showed that self-driving cars are not quite at that level of deductive reasoning
  - jiofih 6y ago
    thats a very general statement, and should be appended with “yet”
- fphhotchips 6y ago
  I'm not so sure about that. I think it would take more than flashing a photo for 100ms (or just putting up a photo at all for that matter) to trigger a human to stop. You have to overcome the context and I think that's harder than "one photo on the side of a highway".
  - jiofih 6y ago
    “putting up a sign on the side of a highway that looks like a photo of a red light”. People have done things like that and it works pretty well. Tech aside, the point is that disrupting traffic or causing accidents is nothing new, you can practice it today just as effectively!
- cambalache 6y ago
  Any human who stops because he saw a red light pic should not be driving in the first place. Fortunately I think that fraction is very small.I certainly hope it does not include you.
  - jiofih 6y ago
    Good for you that you’re immune to optical illusions. Quite a skill to have.
    - cambalache 6y ago
      That is not what optical illusions are.
Mountain_Skies 6y ago
Why would that be a sudden stop unless it is hidden and pops out at the last second? Simply putting up a photo of a traffic light is going to be detected as, well, a traffic light as the car approaches. Maybe with a blind curve or with some other similar obstruction you could create a situation where the photo of the light isn't seen until the last second but you can do the same with human drivers and a fake stop sign.
- TwoHeadedBeast 6y ago
  If it is coming out of a blind curve, then the vehicle should not be going very fast anyway.
derekp7 6y ago
What's to stop someone from throwing out a bunch of jagged glass or nails on the road to puncher someone's tire? Very cheap to deploy and extremely dangerous. The thing that stops this is human decency. And yes, that safeguard does fail sometimes. But fortunately, either situation isn't permanent -- as soon as a cop (or any city employee or private citizen) drives by and sees it (especially the fake traffic light) they can call it in and have it removed in short order.
mnw21cam 6y ago
I guess it's just that most people aren't murderers. https://xkcd.com/1958/ https://xkcd.com/1958/
TwoHeadedBeast 6y ago
And what about this? https://en.wikipedia.org/wiki/Traffic_Light_Tree https://en.wikipedia.org/wiki/Traffic_Light_Tree

jiofih 6y ago

What stops someone doing that today? Humans are also vulnerable.

conradev 6y ago
Humans would be able to see that it is on a long stretch of straight road with no intersection in sight and so while they might be confused, they would not come to a sudden and instant stop. The paper showed that self-driving cars are not quite at that level of deductive reasoning
- jiofih 6y ago
  thats a very general statement, and should be appended with “yet”
fphhotchips 6y ago
I'm not so sure about that. I think it would take more than flashing a photo for 100ms (or just putting up a photo at all for that matter) to trigger a human to stop. You have to overcome the context and I think that's harder than "one photo on the side of a highway".
- jiofih 6y ago
  “putting up a sign on the side of a highway that looks like a photo of a red light”. People have done things like that and it works pretty well. Tech aside, the point is that disrupting traffic or causing accidents is nothing new, you can practice it today just as effectively!
cambalache 6y ago
Any human who stops because he saw a red light pic should not be driving in the first place. Fortunately I think that fraction is very small.I certainly hope it does not include you.
- jiofih 6y ago
  Good for you that you’re immune to optical illusions. Quite a skill to have.
  - cambalache 6y ago
    That is not what optical illusions are.

Mountain_Skies 6y ago

Why would that be a sudden stop unless it is hidden and pops out at the last second? Simply putting up a photo of a traffic light is going to be detected as, well, a traffic light as the car approaches. Maybe with a blind curve or with some other similar obstruction you could create a situation where the photo of the light isn't seen until the last second but you can do the same with human drivers and a fake stop sign.

TwoHeadedBeast 6y ago
If it is coming out of a blind curve, then the vehicle should not be going very fast anyway.

derekp7 6y ago

What's to stop someone from throwing out a bunch of jagged glass or nails on the road to puncher someone's tire? Very cheap to deploy and extremely dangerous. The thing that stops this is human decency. And yes, that safeguard does fail sometimes. But fortunately, either situation isn't permanent -- as soon as a cop (or any city employee or private citizen) drives by and sees it (especially the fake traffic light) they can call it in and have it removed in short order.

mnw21cam 6y ago

I guess it's just that most people aren't murderers. https://xkcd.com/1958/ https://xkcd.com/1958/

TwoHeadedBeast 6y ago

And what about this? https://en.wikipedia.org/wiki/Traffic_Light_Tree https://en.wikipedia.org/wiki/Traffic_Light_Tree