An Algorithm Determines How Fast You Should Drive On California's I-15 Freeway (sfgate.com)
- Reference: 0183754764
- News link: https://tech.slashdot.org/story/26/06/11/2210215/an-algorithm-determines-how-fast-you-should-drive-on-californias-i-15-freeway
- Source link: https://www.sfgate.com/travel/article/algorithm-smart-california-freeway-22296718.php
> Unlike typical on-ramp stoplights that run on a timer lasting a few seconds, Interstate 15 drivers could find themselves waiting up to four minutes or even longer while the system determines the necessary speed for traffic entering the freeway. By spacing out the cars, transportation officials hope to improve traffic flow, reduce stop-and-go traffic and decrease the amount of time that travelers have to spend on the freeway.
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> The transportation commission spent $33 million to build the project, which will run for two years. Riverside County Transportation Commission spokesperson David Knudsen told SFGATE that if the program is successful, the agency will work with Caltrans to deploy it elsewhere in the county and then potentially to other traffic choke points in California. "This system is a lot less expensive than trying to build new lanes, and so the idea here is let's make the system that we have work better," he said.
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> Knudsen said the program is not managed by artificial intelligence but instead uses advanced sensors in the roadway to monitor real-time traffic conditions and make adjustments. The stretch of freeway that connects Temecula at the Riverside/San Diego County line to the Interstate 215 interchange in Murrieta can be notoriously clogged. What can be less than a 10-minute drive with no traffic can take between 25 and 45 minutes during the afternoon peak period, according to the transportation commission. "The intent is to create a consistent flow of traffic on the freeway system, and the coordinated ramp metering among the three on-ramps ... will help do that," Knudsen said. "If we can manage that, then we can help prevent that stop-and-go traffic frustration that so many people feel ... on the freeway."
[1] https://www.rctc.org/press-release/rctc-launches-california-first-smart-freeway-temecula/
[2] https://www.sfgate.com/travel/article/algorithm-smart-california-freeway-22296718.php
[3] https://www.mainroads.wa.gov.au/technical-commercial/smartfreeways/
[4] https://www.cbsnews.com/colorado/news/meter-system-traffic-flow-interstate-225-c470/
Uhm? (Score:2)
If you have cars waiting for minutes to be able to enter the freeway, doesn't that just mean gridlock at the top of the ramp from a shitload of people trying to get on the freeway?
Are they only implementing this where there are massive multi-lane queue ramps that can handle that kind of queue depth? I'm not familiar enough with the California section of I-15, I don't think I've driven on that in 15 years.
Traffic "engineers" are the worst (Score:2)
The law of unintended consequences comes through strongest in traffic. Put in an extra lane? A later required merge actually slows traffic down overall. Widen the freeway the whole distance, but now the smoothed out corner is sharper, and the traffic slows down at the same spot every single damn day. A local city installed plastic bollards with reflective stickers alongside both sides of a road, eliminating about fifty parking spots. At night, any pedestrian or bicyclist is downright invisible among all
Congesting pricing (Score:2)
How about congestion pricing, which 1) provably works better than anything else and 2) actually generates revenue instead of costing money?
Nah, let's just blow 30 million on a system that will, if anything, make traffic worse.
Probably not as useful. (Score:4, Interesting)
Some states in Europe, e.g. Germany, have been doing similar things for decades.
It does improve flow, ultimately difficult to say by how much. But it's not magic. Probably coupled with a ruthless and stupidly expensive camera based speeding system (i.e. $100 for every 1 mph above the designated flow speed) might work, but otherwise the bottleneck will be slight speeding. It will return laminar flow to oscillatory flow (break & accelerate), then to stop & go pretty soon.
A full highway is a full highway, there's little in the way of magic or capacity to remedy that.
Re:Probably not as useful. (Score:4, Insightful)
A full highway is a full highway, there's little in the way of magic or capacity to remedy that.
Well, not entirely. A highway has more capacity at moderate speeds than at high ones, because you need less space between vehicles.
Re: (Score:3)
This. The problem isn't the technology; that can demonstrably be shown to work in models and simulations because of things like - as you say - needing less space between vehicles, and also more complex things like reducing capillary action in the overall traffic flow (the stop-start effect you often get in heavy traffic). The reason why you don't see those benefits is the growing number of entitled drivers who ignore the signage in the hope of gaming the system for personal gain (e.g. shorter travel time)
Re: (Score:1)
> A full highway is a full highway, there's little in the way of magic or capacity to remedy that.
> Well, not entirely. A highway has more capacity at moderate speeds than at high ones, because you need less space between vehicles.
While this is theoretically a reasonable answer (best for AI drivers driving autonomously at 100MPH with humans asleep in the backseat), it’s not a realistic one today with mostly impatient fallible meatsacks behind the wheel driving at the speed of greed, enhanced by prescription meds.
Highway, implies both high capacity and high speed. If I wanted to average 25MPH on my commute because less space, I’d probably drive some back road every morning, taking in the scenery and maybe some fresher air
Re: (Score:1)
> A full highway is a full highway, there's little in the way of magic or capacity to remedy that.
Offer employment options at night.
Twenty-four whole-ass hours in a day. Circadian rhythms are for dancers.
Re: (Score:2)
The UK has been trying to do something like that, but it isn't going well.
Our "smart" motorways convert the hard shoulder (the outermost lane that was used as a stopping area for broken down vehicles) into a normal lane, and then adds sensors (radar, cameras) to detect stopped or slow vehicles and reduce speed limits. Unfortunately it didn't work very well and people died, so they started adding regular "refuge areas", which are basically little stopping points every half mile or so, off to the side of the
Re: (Score:2)
TFA is about variable speed limits, not what the UK calls smart motorways. You're either mistaken because you've got hung-up on an overloaded term, or you're just plain off-topic.
Variable speed limits work well in the UK, although lack of enforcement and the increasing number of dickheads and shitty drivers who exceed the posted limit or do stupid things like constantly changing lanes can sometimes undermine their efficiency. We seriously need more enforcement by the police and less of the rage bait cultu
Re: (Score:2)
Smart motorways are where most of the variable limits are, that's why I mentioned them.
The problem is that too often they cry wolf. You get a 20 limit, or even a full stop, on a motorway due to some dire risk ahead. But then it turns out there was nothing, or a car drove the wrong way down a slip road for a few seconds before realizing and turning around.
Many people ignore it, so if you do 20, or stop, you have people zooming past at dangerous speeds and risk being hit. The police can't really prosecute you
Re: Probably not as useful. (Score:2)
What you are describing as a fault in the design is actually the intended use: prolong somewhat flowing traffic for as long as possible before a full congestion. I assume you would need a sufficiently long part of the highway to actually see an effect.
Re: (Score:2)
yeah, without enforcing the suggested speed limits, that will never work.