4 ms·
Reminds me of an interesting site[1] I came across a while ago, in which the guy argues very convincingly that traffic jams occur as waves, which are started wh
by ryusage 14y ago
Reminds me of an interesting site[1] I came across a while ago, in which the guy argues very convincingly that traffic jams occur as waves, which are started when even a single car does something to cause the car behind them to slow down (avoiding something, stopping to merge, etc). If it's non-trivial, then that will begin a chain reaction - a wave propagating through a medium of cars. The severity of that effect is directly proportional to the density of the medium/traffic.
Given that perspective, metering lights to reduce density seem like exactly the right solution.
[1] http://trafficwaves.org http://trafficwaves.org
- defrost 14y agoThe first time I heard about traffic waves and the use of active feedback to eliminate traffic jams was from [Prof. John Mahoney](http://www.asap.unimelb.edu.au/bsparcs/aasmemoirs/mahony.htm http://www.asap.unimelb.edu.au/bsparcs/aasmemoirs/mahony.htm) in 1984, he gave two 45 minute lectures on the subject and later in the year posed two related unsolved problems in the area on our exams, we were undergraduates at the time but that was typical of him to make up exams at the last minute and pack them with current problems from either current literature or his in-tray.
- Lost_BiomedE 14y agoMy father, in grad school, worked in a lab with a guy who pioneered a lot of this research. He showed the coil like action of these waves and how they created wrecks. Here are some other things I thought were cool: He calculated the risk of changing lanes on a highway and estimated how much people valued their lives in dollars (usually fractions thereof) based on this one criteria. He drove vehicles into lakes to study the escape from such a vehicle. He tracked the eyes of truckers and found that their eyes would fall to the front of the hood and dart up a few times about 30-45s before they fell asleep and wrecked. Another guy tried to make a talking highway by varying the distance of groves and marks on the road. Just thought some might find this stuff interesting or amusing.
- gwillen 14y agoI'd be curious if you have data on the risk of lane-changes. (Knowing how dangerous they are would probably cause me to do fewer of them.)
- sliverstorm 14y agoI would guess the risk is not all that significant in the scheme of things. Just another one of those, "Look, you say human lives are priceless, but here I will prove they do have a price (whatever that might be)" type deals.
- bjustin 14y agoHonda made a road that plays part of the William Tell Overture[1]. It doesn't sound right, but the effect was still fun when I tried it. [1] http://en.wikipedia.org/wiki/Musical_road#Civic_Musical_Road http://en.wikipedia.org/wiki/Musical_road#Civic_Musical_Road
- smosher 14y agoThis is exactly what I was thinking of when I saw the article. I was impressed by how obvious it seemed after having read about it.
- kidnoodle 14y agoYuki Sugiyama and co did some lovely research on this phenomena and were able to reproduce it on a circular road. A rather splendid video of said experiment: http://www.youtube.com/watch?v=7wm-pZp_mi0 http://www.youtube.com/watch?v=7wm-pZp_mi0
- ryusage 14y agoAwesome! I just saw their paper from the trafficwaves site a little bit ago and was curious what this would really look like. I like their point that a car suddenly slowing down is not really to blame for the jam, but rather an inevitable trigger that happens after a certain critical density is reached.