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Magic Roundabout (Swindon)

en.wikipedia.org

161–170 of 199 posts

Re: Magic Roundabout (Swindon)

#161
post #79

Earlier quoted context omitted.

Isn't a two-lane roundabout one that simply has two lanes going round? The thing about the turbo-roundabout is that there are actually no lanes going round. Each lane just takes you to your exit. There's no option to stay on the roundabout at that point: you're forced off. It's very restrictive in that sense, but that also means that traffic flows smoothly: other drivers also have no option to merge wrong or try anyt…

> other drivers also have no option to merge wrong or try anything weird If they're following the markings, yes. We have a 1.5-lane roundabout in my area[1] (two lanes on the north side of the circle, one lane on the south side) fed on the southwest by a two-lane road; the right lane is supposed to be a bypass for vehicles turning right, and does not actually enter the roundabout. Some vehicles still make the attempt…

In turbo roundabouts, the markings are usually delineated by raised curbs.

The one you linked should've physically separated the right turn lane from the rest of the roundabout if that was the intention. You don't need all that much curb to do it.

Re: Magic Roundabout (Swindon)

#163
post #162

If this was voted the 4th scariest intersection where the first 3? NVM: Found the answer in the wiki. http://news.bbc.co.uk/2/hi/uk_news/england/london/7140892.st...

In usual fashion, Wikipedia links sources where they can. In this case, this is the source: http://news.bbc.co.uk/2/hi/uk_news/scotland/glasgow_and_west...

Re: Magic Roundabout (Swindon)

#164
post #78

> however, the roundabout provides a better throughput of traffic than other designs and has an excellent safety record, since traffic moves too slowly to do serious damage in the event of a collision. In 2010, the National Cooperative Highway Research Program concluded that the roundabout reduces injurious crashes by three quarters. One of the hardest things in local democracy is that the best traffic patterns are o…

The problem, as always, is that parties disagree on what "best" means. Governments and safety organizations are pushing for "Vision Zero", i.e., safety at any cost. (My economics professor once pointed out that if you really want zero traffic deaths, just limit all cars to 5 mph everywhere.) For people driving on the road, the current level of risk (roughly 1 death per 100M miles) is acceptable, and arriving quickly…

If they really want to reach zero the only answer is a combination of self-driving cars (remove the idiot monkey) and proper pedestrian management to have dedicated crossings, away from the automated intersections.

Re: Magic Roundabout (Swindon)

#165
post #43

A better solution for high traffic flow is the turbo roundabout[0] which is getting increasingly popular in Netherland. Before you enter the roundabout, you select the lane for the direction you want to go. You only cross traffic when entering the roundabout for the first time. After that, you simply follow your lane and it delivery you where you want to go. It looks complicated from above, but it's very simple once…

I don't like it. From the bottom, if you want to go straight you enter on the right lane. From the right, if you want to go straight you enter on the left lane. This lack of symmetry means you need to be very familiar with the path in advance, and not get confused about which orientation you're in. For the signage to be far enough from the roundabout to get your bearings in time, it will be too far for most people to…

Late merges are optimal, and the fact that so many people disagree with this practice (or take it as a personal affront) is one of several gross failures of US driver education programs.

However, yes, complicated roundabouts that require perfect knowledge of what lane you need in order to take an exit you can't see in advance do suck. If you find yourself installing a roundabout with more than one lane, you probably should be installing a traffic light instead.

Re: Magic Roundabout (Swindon)

#166
post #43

A better solution for high traffic flow is the turbo roundabout[0] which is getting increasingly popular in Netherland. Before you enter the roundabout, you select the lane for the direction you want to go. You only cross traffic when entering the roundabout for the first time. After that, you simply follow your lane and it delivery you where you want to go. It looks complicated from above, but it's very simple once…

This[0] is a very elaborate version of the turbo roundabout, checking it out in streetview might help. But basically the roundabout functions more like a standard junction with room to choose a direction before turning (I don't think there is an English translation for "voorsorteren", or sort before...). [0] https://www.google.com/maps/place/Energieweg,+Nijmegen/@51.8...

"presorted" "prefiltered" would be adequate translations, but sort is a bit of an odd word to use for traffic in English.

Re: Magic Roundabout (Swindon)

#167
post #43

A better solution for high traffic flow is the turbo roundabout[0] which is getting increasingly popular in Netherland. Before you enter the roundabout, you select the lane for the direction you want to go. You only cross traffic when entering the roundabout for the first time. After that, you simply follow your lane and it delivery you where you want to go. It looks complicated from above, but it's very simple once…

I expect most are better given that "In 2009 it was voted the fourth scariest junction in Britain."

Re: Magic Roundabout (Swindon)

#168
post #43

A better solution for high traffic flow is the turbo roundabout[0] which is getting increasingly popular in Netherland. Before you enter the roundabout, you select the lane for the direction you want to go. You only cross traffic when entering the roundabout for the first time. After that, you simply follow your lane and it delivery you where you want to go. It looks complicated from above, but it's very simple once…

> A better solution for high traffic flow is the turbo roundabout

Q: Is such a construction grade-separated and/or are the separate flows in controlled by traffic lights? The diagram isn't that clear...

Re: Magic Roundabout (Swindon)

#169
post #43

A better solution for high traffic flow is the turbo roundabout[0] which is getting increasingly popular in Netherland. Before you enter the roundabout, you select the lane for the direction you want to go. You only cross traffic when entering the roundabout for the first time. After that, you simply follow your lane and it delivery you where you want to go. It looks complicated from above, but it's very simple once…

Looks like it works with 4 roads, how about 5 like this one?

Re: Magic Roundabout (Swindon)

#170
post #125

For a real nightmare roundabout, the winner has to be Place Charles de Gaulle around the Arc de Triumph in Paris[0]. It is about 8 lanes across, with no lane markings, and with vehicles entering the roundabout from one of 12 junctions having right-of-way. I'm not sure what was happening on the day the Google maps aerial photo was taken, as it unfortunately it doesn't show the chaos that normally ensues. [0] https://w…

In my private vernacular, it was specifically visiting the Arc de Triomph that prompted me to coin the term "traffic tornado" and note other, invariably less turbulent ones that I find in life.

It is spectacular for being such a point of interest for visitors and to then be so unfriendly to our squishy bodies and a rather unpleasant assault on the senses.

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