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That's not what the article is saying. They have tested ant flow on narrow bridges where additional lanes aren't possible. From the article: "they do this thr

That's not what the article is saying. They have tested ant flow on narrow bridges where additional lanes aren't possible. From the article: "they do this through self-imposed speed regulation. When it's moderately busy, for instance, the authors found the ants actually speed up, accelerating until a maximum flow or capacity is reached. Whereas, when a trail is overcrowded, the ants restrained themselves and avoided joining until things thinned out. Plus, at high density times like this, the ants were found to change their behaviour and slow down to avoid more time-wasting collisions." We'll be finally able to traffic jam free when autopilot will make us slow appropriately in high density conditions, avoiding accordion-like brake/accelerate/brake cycles

pif 7y ago
> We'll be finally able to traffic jam free when autopilot will make us slow appropriately in high density conditions... It looks wonderful! Just, please, add the option into your autopilot to let me pass before playing with the best jam-reabsorbing strategy! I need to go places, not like the rest of you who hit the road just for fun!
CodesInChaos 7y ago
Congestion dependent speed limits have been in use for a long time on German highways.
- Spare_account 7y ago
  The principle is sound, but the ants actually obey the rules whereas (in the UK at least) a small contingent of human drivers will ignore the limits, speeding up and slowing down between enforcement cameras. This concertina effect from just a small number of drivers is enough to slow the entire flow of traffic.
  - lotsofpulp 7y ago
    It would have happened anyway after a certain density of vehicles is exceeded, since each car and truck had different accel/decel rates. Especially if there is an incline anywhere.
- donmatito 7y ago
  yes, speed reduction on the Paris belt was also done in order to reduce traffic jams. The argument was "peak speed is slower, but apart from night/holidays situation with empty road, you'll actually get faster to where you're going because of less jams"
lotsofpulp 7y ago
> We'll be finally able to traffic jam free when autopilot will make us slow appropriately in high density conditions, avoiding accordion-like brake/accelerate/brake cycles No, because each vehicle has different acceleration and deceleration rates. Watch any road with an incline and you will see congestion develop relatively quickly before the incline. And a traffic jam is inevitable when the bandwidth of a road has been exceeded. Each vehicle needs a certain amount of space in front of it, and behind it. The faster it goes, the more space it is, as well as if it’s heavy. This means for a given number of lanes, at a given speed, there exists a max number of vehicles. Once this maximum is exceeded, speed must drop as it is no longer safe to travel so close to vehicles in front and behind, and so bandwidth also drops. Hence, traffic jam. The different accel/decel rates contribute to the congestion also, as vehicles need varying amounts of time to fill the space in front of them. Bottom line, there is no solution to traffic jams other than reducing space needed to travel Per person (trains instead of cars), or increasing speeds (not possible in cars on current roads without exceeding acceptable safety risks), increasing the number of lanes (space is usually not available), and the easiest option, reduce the number of vehicles traveling the road via variable tolling based on congestion (currently the best option in my opinion).
- Retric 7y ago
  Humans don’t closely approach the theoretical limits of highway capacity. They encounter a much lower limit and get stuck in a range of suboptimal choices.
  - lotsofpulp 7y ago
    I can see it helping a little in cases where congestion is caused by some less than ideal braking, but in urban areas where the congestion is frequently due to merges or in a hilly area where trucks are going slower in one or two lanes, I don’t see it helping much. In rush hour, the cars are bumper to bumper, it’s because of all the cars entering the same roadway needing to merge in. Also, I would assume any congestion alleviated would be offset by induced demand by the people who now see less congestion and decide its worth it to jump on the road.

pif 7y ago

> We'll be finally able to traffic jam free when autopilot will make us slow appropriately in high density conditions... It looks wonderful! Just, please, add the option into your autopilot to let me pass before playing with the best jam-reabsorbing strategy! I need to go places, not like the rest of you who hit the road just for fun!

CodesInChaos 7y ago

Congestion dependent speed limits have been in use for a long time on German highways.

Spare_account 7y ago
The principle is sound, but the ants actually obey the rules whereas (in the UK at least) a small contingent of human drivers will ignore the limits, speeding up and slowing down between enforcement cameras. This concertina effect from just a small number of drivers is enough to slow the entire flow of traffic.
- lotsofpulp 7y ago
  It would have happened anyway after a certain density of vehicles is exceeded, since each car and truck had different accel/decel rates. Especially if there is an incline anywhere.
donmatito 7y ago
yes, speed reduction on the Paris belt was also done in order to reduce traffic jams. The argument was "peak speed is slower, but apart from night/holidays situation with empty road, you'll actually get faster to where you're going because of less jams"

lotsofpulp 7y ago

> We'll be finally able to traffic jam free when autopilot will make us slow appropriately in high density conditions, avoiding accordion-like brake/accelerate/brake cycles No, because each vehicle has different acceleration and deceleration rates. Watch any road with an incline and you will see congestion develop relatively quickly before the incline. And a traffic jam is inevitable when the bandwidth of a road has been exceeded. Each vehicle needs a certain amount of space in front of it, and behind it. The faster it goes, the more space it is, as well as if it’s heavy. This means for a given number of lanes, at a given speed, there exists a max number of vehicles. Once this maximum is exceeded, speed must drop as it is no longer safe to travel so close to vehicles in front and behind, and so bandwidth also drops. Hence, traffic jam. The different accel/decel rates contribute to the congestion also, as vehicles need varying amounts of time to fill the space in front of them. Bottom line, there is no solution to traffic jams other than reducing space needed to travel Per person (trains instead of cars), or increasing speeds (not possible in cars on current roads without exceeding acceptable safety risks), increasing the number of lanes (space is usually not available), and the easiest option, reduce the number of vehicles traveling the road via variable tolling based on congestion (currently the best option in my opinion).

Retric 7y ago
Humans don’t closely approach the theoretical limits of highway capacity. They encounter a much lower limit and get stuck in a range of suboptimal choices.
- lotsofpulp 7y ago
  I can see it helping a little in cases where congestion is caused by some less than ideal braking, but in urban areas where the congestion is frequently due to merges or in a hilly area where trucks are going slower in one or two lanes, I don’t see it helping much. In rush hour, the cars are bumper to bumper, it’s because of all the cars entering the same roadway needing to merge in. Also, I would assume any congestion alleviated would be offset by induced demand by the people who now see less congestion and decide its worth it to jump on the road.