Burrstone Posted October 17, 2013 Share #26 Posted October 17, 2013 The problem is that green waves only work in one direction - the other direction is going to get the short end of the stick if it's a two-way road. How? They both (usually) get to go at the same time, so whether it's a two lane road or or a one way street, its the same thing... None of them of them is going to get the short end of the stick, as they are moving in the opposite direction, both would (usually) get the green at the same time. Link to comment Share on other sites More sharing options...
Trainmaster5 Posted October 18, 2013 Share #27 Posted October 18, 2013 How? They both (usually) get to go at the same time, so whether it's a two lane road or or a one way street, its the same thing... None of them of them is going to get the short end of the stick, as they are moving in the opposite direction, both would (usually) get the green at the same time. I see where you're coming from. My argument is that one direction has travel in the peak time so traffic is slower. More cars = a slowdown. Meanwhile the cars traveling in the opposite direction are not slowed down because there isn't that glut of cars so they can travel a longer distance at a higher speed before the red light catches them. Obviously at 10 pm Monday through Thursday Sunrise Highway e/b is pretty much wide open once you get past Lynbrook . Friday nights bring out 5-0 so things slow down a bit. Link to comment Share on other sites More sharing options...
bobtehpanda Posted October 18, 2013 Share #28 Posted October 18, 2013 How? They both (usually) get to go at the same time, so whether it's a two lane road or or a one way street, its the same thing... None of them of them is going to get the short end of the stick, as they are moving in the opposite direction, both would (usually) get the green at the same time. Green waves can only cascade in one direction, not two. If you have green waves for westbound drivers, red lights are going to do the opposite of a green wave for eastbound travelers. Think of it this way - pretend a green wave is a train, with the front as the beginning and the back marking when the greens turn red. People traveling in the opposite direction at the same speed on another train will reach the back of the first train twice as fast as they would've if they were staying in place. Link to comment Share on other sites More sharing options...
Burrstone Posted October 18, 2013 Share #29 Posted October 18, 2013 If traffic is moving in opposite directions, let's use east and west, they should never cross because they are parallel. They would never even need a light if it weren't for traffic from north and south roads crossing east and west roads. So how exactly would optimizing traffic patterns affect and even slow down traffic going in the opposite/parallel direction? A majority of the time you are driving (let's say east) traffic opposite of you has what when you have a green? A green! Unless there is a left turn arrow.... Link to comment Share on other sites More sharing options...
bobtehpanda Posted October 19, 2013 Share #30 Posted October 19, 2013 If traffic is moving in opposite directions, let's use east and west, they should never cross because they are parallel. They would never even need a light if it weren't for traffic from north and south roads crossing east and west roads. So how exactly would optimizing traffic patterns affect and even slow down traffic going in the opposite/parallel direction? A majority of the time you are driving (let's say east) traffic opposite of you has what when you have a green? A green! Unless there is a left turn arrow.... Greens come in waves; however, the reds also come in waves. It's not about what the light is at the current intersection; it's about when the light changes. For example, let's say that a green wave has traffic signals that turn green when a car is traveling at 30MPH west. For every traffic light that turns green in the front of the cars, whatever traffic light at the end of the green wave has to turn red - otherwise, you'd have all greens, all the time. This means that the red lights at the back of the green wave are also traveling west at 30MPH. If a car is traveling eastbound at 30MPH while this is happening, the car and red light are approaching each other at 60MPH, which means it would be experiencing red lights twice as frequently as it would be if there was no green wave. Traffic management is a zero-sum game - some win, and some lose. You can't really tinker with individual lights, either - everything has to be fine tuned, and there is no perfect setup that works 100% of the time. It's why Siemens, Cisco, and all those other information companies are hawking 'smart' traffic light software that can change timings according to road conditions. (For the purposes of this argument, I'm assuming we're talking about roads that have at-grade intersections, because highway engineering is a completely different animal.) Link to comment Share on other sites More sharing options...
Vistausss Posted October 19, 2013 Share #31 Posted October 19, 2013 Green waves on lanes for straight on traffic can happen in both directions. My city has a few roads with green waves so I can tell you out of experience that it does work that way. Link to comment Share on other sites More sharing options...
Burrstone Posted October 19, 2013 Share #32 Posted October 19, 2013 Greens come in waves; however, the reds also come in waves. It's not about what the light is at the current intersection; it's about when the light changes. For example, let's say that a green wave has traffic signals that turn green when a car is traveling at 30MPH west. For every traffic light that turns green in the front of the cars, whatever traffic light at the end of the green wave has to turn red - otherwise, you'd have all greens, all the time. This means that the red lights at the back of the green wave are also traveling west at 30MPH. If a car is traveling eastbound at 30MPH while this is happening, the car and red light are approaching each other at 60MPH, which means it would be experiencing red lights twice as frequently as it would be if there was no green wave. Traffic management is a zero-sum game - some win, and some lose. You can't really tinker with individual lights, either - everything has to be fine tuned, and there is no perfect setup that works 100% of the time. It's why Siemens, Cisco, and all those other information companies are hawking 'smart' traffic light software that can change timings according to road conditions. (For the purposes of this argument, I'm assuming we're talking about roads that have at-grade intersections, because highway engineering is a completely different animal.) Greens come in waves; however, the reds also come in waves. It's not about what the light is at the current intersection; it's about when the light changes. For example, let's say that a green wave has traffic signals that turn green when a car is traveling at 30MPH west. For every traffic light that turns green in the front of the cars, whatever traffic light at the end of the green wave has to turn red - otherwise, you'd have all greens, all the time. This means that the red lights at the back of the green wave are also traveling west at 30MPH. If a car is traveling eastbound at 30MPH while this is happening, the car and red light are approaching each other at 60MPH, which means it would be experiencing red lights twice as frequently as it would be if there was no green wave. Traffic management is a zero-sum game - some win, and some lose. You can't really tinker with individual lights, either - everything has to be fine tuned, and there is no perfect setup that works 100% of the time. It's why Siemens, Cisco, and all those other information companies are hawking 'smart' traffic light software that can change timings according to road conditions. (For the purposes of this argument, I'm assuming we're talking about roads that have at-grade intersections, because highway engineering is a completely different animal.) Are you screwing around with me? It's like beating my head against a wall. Link to comment Share on other sites More sharing options...
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