4 ms·

I hadn’t heard of this approach before. Clever. At what distance does the light turn green? Is it easy to spoil for safe drivers by coming up behind them?

gjsman-1000 3y ago
Hold on - what if I’m flying in, it turns red. I then sit there at a red light, unable to move forward. What’s the escape route I’m missing?
- p1mrx 3y ago
  If you're stopped at a red light, you are most likely driving below the speed limit.
- stephen_g 3y ago
  I’m guessing it just stays red for long enough to be annoying and then lets you through?
  - fransje26 3y ago
    Exactly. It stays red for a few seconds.
fransje26 3y ago
If you are respecting the speed limit, it turns green well before you would have to hit the brakes to come to stop. > Is it easy to spoil for safe drivers by coming up behind them? What? No. You are first in line, at the correct speed, so why would the light react to somebody coming behind you? The other car cannot go through you, so they will have to slow down no matter what.
- 1123581321 3y ago
  Right, so the question comes from combining the two things you said. You get a green while you’re still a ways back, and proceed forward. A speeder crosses that same trigger point before you’ve gotten through the intersection. They’re trying to catch up with you so they get through the light right behind you. Do they get a free green or do they make your light turn red while you’re far enough back to have to stop? Have you used it, by the way? My question was about the specific timing and placement of the trigger.
  - fransje26 3y ago
    > Have you used it, by the way? I have not used FRED no, but living in Europe, I have frequently come across dynamic stop lights, yes. > A speeder crosses that same trigger point [..] Do they get a free green or do they make your light turn red. Normally they are not controlled via a single trigger point, but with a dynamic radar system. So even if you come in too fast, turning the light red, it can still switch back to green if you slow down in time. I don't know how the beam discrimination works if it detects scatter from a faster moving object behind you, but in practice I've never encountered a scenario where I was forced to stop because someone was coming in faster from behind.
    - 1123581321 3y ago
      Gotcha. Thanks! I hope to experience one of these.

gjsman-1000 3y ago

Hold on - what if I’m flying in, it turns red. I then sit there at a red light, unable to move forward. What’s the escape route I’m missing?

p1mrx 3y ago
If you're stopped at a red light, you are most likely driving below the speed limit.
stephen_g 3y ago
I’m guessing it just stays red for long enough to be annoying and then lets you through?
- fransje26 3y ago
  Exactly. It stays red for a few seconds.

fransje26 3y ago

If you are respecting the speed limit, it turns green well before you would have to hit the brakes to come to stop. > Is it easy to spoil for safe drivers by coming up behind them? What? No. You are first in line, at the correct speed, so why would the light react to somebody coming behind you? The other car cannot go through you, so they will have to slow down no matter what.

1123581321 3y ago
Right, so the question comes from combining the two things you said. You get a green while you’re still a ways back, and proceed forward. A speeder crosses that same trigger point before you’ve gotten through the intersection. They’re trying to catch up with you so they get through the light right behind you. Do they get a free green or do they make your light turn red while you’re far enough back to have to stop? Have you used it, by the way? My question was about the specific timing and placement of the trigger.
- fransje26 3y ago
  > Have you used it, by the way? I have not used FRED no, but living in Europe, I have frequently come across dynamic stop lights, yes. > A speeder crosses that same trigger point [..] Do they get a free green or do they make your light turn red. Normally they are not controlled via a single trigger point, but with a dynamic radar system. So even if you come in too fast, turning the light red, it can still switch back to green if you slow down in time. I don't know how the beam discrimination works if it detects scatter from a faster moving object behind you, but in practice I've never encountered a scenario where I was forced to stop because someone was coming in faster from behind.
  - 1123581321 3y ago
    Gotcha. Thanks! I hope to experience one of these.