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Old June 14th, 2008, 12:19 AM   #61
UrbanBen
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They've been talking theory for 50 years.
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Old June 14th, 2008, 12:58 AM   #62
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Quote:
Originally Posted by Shado View Post
It's not going to work as a competitor to cars without using almost as much surface area as cars do, which is already heaps.
That's simply not true. Look at the designs - the only intersection with the street is a few support posts every 50 feet. It would take 6 of these support posts to fill a single parking space. Elevated stations would only consume as much street space as a bus shelter.

The most significant impact on the street level would be a thin shadow.
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Old June 14th, 2008, 01:55 AM   #63
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Automated routing systems are not exclusive to PRT. There are test runs with driverless metros and some are existing (Paris). You can automate almost every transport system.
But the comparison was to congestion in cars, and PRT is superior to cars in this regard.

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Originally Posted by wonwiin View Post
For me a segregated guideway is actually not really positive. It is easy to install in a new city but given that most cities are quite old and dense you have to install yet another system. Light rail has the flexibility to be able to use the same streets as cars in the city center and use seperated tracks in the outskirts.
Agreed, there are certainly areas which are not ideal for PRT, at least not in the short term. It's not a universal solution.

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Originally Posted by wonwiin View Post
Also to make a grade seperated PRT effective you actually have to copy most of the street map of the city with the new guideways and this will get expensive. Without that rerouting won't be easy.
Yes, that's true, but the system can start small and build up. In the early stages when there are a small number of stations, demand will be lower anyways because there are fewer areas served. As the network builds up, capacity increases as the demand increases.

If it's so popular early on that congestion becomes an issue, you can bump fares and use the added revenue to expand the network on a faster schedule. That's a nice problem to have. :-)

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Originally Posted by wonwiin View Post
Vehicle breakdowns will occure more often than in a metro, light rail or bus system because of the higher number of vehicles needed alone to operate PRTs.
No, there is a difference between component breakdowns and vehicle breakdowns. In a checked redundant system, vital components are both redundant and monitored. So you have (e.g.) two completely independent brake systems, and when one malfunctions, the vehicle is automatically directed to the maintenance garage for repair before that component breakdown causes a vehicle breakdown.

For especially crucial components, there may even be multiple redundancy - 3 or more redundant versions of the same component. This is why air travel is so safe, because no single failure will bring down an aircraft.

An automated system like PRT would never make it past regulatory approval without a thorough examination of the safety engineering.


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The easiest way is actually the bus. Nothing beats the bus in flexibility in operations.
Yes, that's true. But buses are operationally inefficient (especially now with oil prices surging), so that theoretical flexibility is tempered by practical financial reality. It's very expensive to run bus service in low demand areas, or at low demand times of the day. This is due to the energy costs of moving that big piece of metal up and down the line, as well as the cost of the driver.

With PRT, there is almost no operational cost penalty for operating in low demand areas or off-peak times. So while PRT may be more difficult to start up than a bus line, it is flexible in other ways.

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Originally Posted by wonwiin View Post
You are welcome. Just to say I do like Monorails, PRTs, etc. But to replace established systems PRT and especially Monorail are missing the revolutionary new way of doing things. Why would I invest in a system I have to built a totally new infrastructure for doing more or less the same as my already established public transport systems?
I agree that it's difficult to see the benefit in a paper system. Perhaps once people see what PRT can do, it will become more accepted - people might even demand it in their cities. So it will be very interesting to see what Heathrow and Masdar City can do with it.

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Originally Posted by wonwiin View Post
Another point against PRT is, that it not only competes against mass transit but also even more against the car. And it is really difficult to compete against it. The car is, as already said, the ultimate PRT.
But with rising congestion and oil prices, cars are becoming less attractive. People may be more receptive to change than you think.

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Having seen quite a few computer systems that deal with routing, they become incredibly complex as you increase the number of nodes and items using them. I've seen people write systems with just a couple (in this case they were simply automated forklifts) and no matter how hard they tried, the system was still more efficient with a single forklift than it was trying to have the two avoid each other. (They would spend more time getting out of each others way than doing what they were supposed to).

Obviously the best way for people to determine if PRT works, and in what situations it works in is to build it and see what happens. We can talk theory all we want, but eventually it becomes a circular argument. If someone builds it and it's cost effective and works, it will be repeated until someone puts it in a situation that exceeds what it's capable of and then we know the boundries. If someone builds it and there are problems, it all gets put on the shelf until someone claims to solve them.
Well, I disagree with your forklift example. Anything can be done badly. ;-) I've seen PRT simulations in action, and there is little problem with routing.

But I agree with your second point, that a lot of questions will be answered once it's built. But there are some who are so convinced it won't work (against all available evidence) that they campaign heavily against the mere mention of PRT. That's what bugs me. We need to keep an open mind to new ideas.

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They've been talking theory for 50 years.
Is there a statute of limitations on innovation? :-) Technology has finally caught up to the theory, that's all.
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Old June 14th, 2008, 02:45 AM   #64
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Eventually, PRT will prevail, but not in the form that PRT advocates have in mind.

Within the next few years, plug-in hybrid cars will be on the market that are powered by a new generation of lithium batteries that will allow the typically commuter to travel to and from work on battery power alone. GPS systems that provide driving directions to any chosen destination are now in common use and one of the Japanese auto firms is now offering a car that can parallel park itself. Eventually, these features will be brought together to provide a car that is powered by batteries and can drive itself. All the essential features of PRT will be present in the family car.
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Old June 14th, 2008, 05:31 AM   #65
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Eventually, PRT will prevail, but not in the form that PRT advocates have in mind.

Within the next few years, plug-in hybrid cars will be on the market that are powered by a new generation of lithium batteries that will allow the typically commuter to travel to and from work on battery power alone. GPS systems that provide driving directions to any chosen destination are now in common use and one of the Japanese auto firms is now offering a car that can parallel park itself. Eventually, these features will be brought together to provide a car that is powered by batteries and can drive itself. All the essential features of PRT will be present in the family car.
I think it will be decades before cars can drive themselves on regular roads. Driving an automobile is a distinctly human capability. It involves reliable split-second recognition of all manner of obstacles, and the ability to do it rain or shine, day or night.

Humans are able to correctly detect and react to hazards a very high percentage of time, probably exceeding 99.9%. In contrast, modern artificial intelligence (AI) algorithms are notoriously bad at mimicking human perception. Even in controlled environments they are far less reliable than a small child at recognizing patterns and objects. A state-of-the-art AI algorithm might get it right 95% of the time under ideal conditions, but that's way too unreliable for operating an automobile on city streets, where one mistake can be fatal and a 5% failure rate would cause absolute chaos. And closing that 5% gap is unimaginably difficult, becuase the nature of AI problems is such that the closer you get to perfection, the more difficult the problem comes, at an exponential rate. It might take 10 years to go from 95% to 97%, then another 10 years to get to 97.5%, and so on.

Parallel parking systems exist today only because it is a very tightly-bounded application that occurs at idling speeds.

PRT systems get around this by embedding the system in a closed loop, segregating it from all other traffic, and using electronic signaling rather than audio-visual cues: instead of blinking colored lights (traffic signals) there is industrial grade networking; instead of yellow lines on pavement, there is a fixed guideway with fail-safe switching; instead of a red octagon with lettering, there are millimeter-accurate position sensors.

Roads are tailored for human perception. The PRT guideway is hand tailored for automated control.
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Old June 14th, 2008, 06:13 AM   #66
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You guys are funny. Self-driving cars, sure - could work. Won't happen, though - when you give people a car, they want to drive it themselves.

Plug-in hybrids? Good luck affording those batteries! There's a reason the Tesla is $109k - it's a sports car as a side effect of making it light enough to carry a decent range of batteries. It's been easy to make electric motors with that kind of performance for 100 years, but it's not easy to make the batteries and frame light enough to drag it for 250 miles.
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Old June 14th, 2008, 11:20 AM   #67
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That's simply not true. Look at the designs - the only intersection with the street is a few support posts every 50 feet. It would take 6 of these support posts to fill a single parking space. Elevated stations would only consume as much street space as a bus shelter.

The most significant impact on the street level would be a thin shadow.
You could argue that you could elevate cars and they would take no room either. We're talking surface area regardless of if it's underground, elevated or at grade. Airspace is a valuable resource that can actually fetch good money here. Just because it takes up less room on the ground doesn't mean it magically takes up no space.

Quote:
I think it will be decades before cars can drive themselves on regular roads. Driving an automobile is a distinctly human capability. It involves reliable split-second recognition of all manner of obstacles, and the ability to do it rain or shine, day or night.
They can already do it, but the problem is that people will accept an accident/fatality caused by a human, they won't accept one that has the remotest possibilty of being caused by a computer.

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as a side effect of making it light
Like PRT ? PRT is electric guided cars.

Quote:
There's a reason the Tesla is $109k
Yeah it's first generation technology being built in very small numbers. The performance hasn't been around for 100 years, go and have a look at the 100 year old electric cars. The innovations in the last 100 years have been quite significant, no one has put them into practice as well until recently though. The battery technology is hugely different, the motors are different and incorporate regenerative breaking etc.

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Well, I disagree with your forklift example. Anything can be done badly. ;-) I've seen PRT simulations in action, and there is little problem with routing.
Simulations are one thing, but as I've said, you have to put it into practice to see how it works. Anything is possible 'in theory'. Eventually most things fall to a cost/benefit analysis.
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Old June 14th, 2008, 02:22 PM   #68
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You guys are funny. Self-driving cars, sure - could work. Won't happen, though - when you give people a car, they want to drive it themselves.

Plug-in hybrids? Good luck affording those batteries! There's a reason the Tesla is $109k - it's a sports car as a side effect of making it light enough to carry a decent range of batteries. It's been easy to make electric motors with that kind of performance for 100 years, but it's not easy to make the batteries and frame light enough to drag it for 250 miles.
The self-driving car might still be decades away, but the essential technologies are already available. The Department of Defense has funded a competition that has demonstrated the basic feasibility < http://www.darpa.mil/GRANDCHALLENGE/ >. I expect that self-driving weapons systems could appear within the next decade. I expect there will be legal hurdles that will prevent such a system from going into civilian use for several more decades, but ultimately it will prove safer to let a computer drive rather than an onboard human.

Regarding plug-in hybrids, General Motors plans to make one available through your local Chevrolet dealership by the end of 2010 < http://www.chevrolet.com/electriccar/ >. Toyota is developing a similar model. Nissan is developing an all electric version. I am sure the other automakers have their own variants in various states of design.
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Old June 14th, 2008, 02:50 PM   #69
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For the convenience of forum members, I am posting some of the text from the websites referenced in the above post:

=========================================================

DARPA Grand Challange for Autonomous Vehicles

http://www.darpa.mil/GRANDCHALLENGE/

...

Final Event

After tallying all of the NQE scores, DARPA announced on November 1, 2007, that 11 teams would be competing in the Final Event. And so at sunrise on November 3, in front of a crowd of thousands on hand to witness history being made, Dr. Tether, DARPA Director, raised the green flag and the race was on. One by one, all 11 finalist robots were released from their starting chutes, followed by a chase vehicle equipped with an emergency stop control.

The course for the final event was communicated to the teams in the form of two files, analogous to a map and a specific mission. Upon announcing the finalist selections on November 1, teams were given the ‘map’ file of the final course (Route Network Definition File). However, each team didn’t receive their Mission Definition File, which lists the order of checkpoints they had to visit, until five minutes before they launched on race day. With this approach, the teams had no a priori knowledge of their missions, creating a truly autonomous driving test.

Thirty manned traffic vehicles were also released onto the course to increase traffic density. This fleet of Ford Tauruses were retrofitted with safety cages, race seats, fire systems, radios and tracking systems, and were driven by professional drivers. In all, over 50 vehicles, both manned and unmanned, were navigating the city streets simultaneously during the final event.

DARPA staff were scattered throughout the course serving as safety officials, noting any errant or unsafe behaviors which would eventually be counted in a team’s final score. The Command Operations Center (COC) served as the central hub for all race monitoring, where DARPA staff tracked all vehicles, initiating coursewide emergency-stop commands to the robots as necessary.

After strong starts by all the finalists, by mid-morning almost half of the field had been removed from the race for a variety of reasons. Terramax, a returning crowd favorite, went awry in a parking lot, and was stopped moments before entering the old commissary building. Team UCF decided to take a break and pulled off the road and into a carport before being removed from the race by officials.

Despite these hiccups, six teams emerged as strong contenders as they methodically picked through their missions. Early afternoon brought the first true accident of the day when Cornell and MIT bumped sides at low speed as they tried to share a lane. The robots were separated and allowed to resume their missions.

Highlight videos and pictures of the NQE and Final Event can be found in the Gallery. DARPA broadcasted the event live to the world over the internet and had a huge viewing audience in the event tent, where live footage was projected on giant screens.

As the day wore on, it became apparent to all that this race was going to have finishers, and that it was going to be a close one. At 1:43 pm, Stanford’s entry, “Junior” crossed the finish line first with a run-time of just over four hours. A minute later, Tartan Racing’s “Boss” crossed the finish line. It was a scene that would be repeated over and over as six robots eventually crossed the finish line, an astounding feat for the teams and proving to the world that autonomous urban driving could become a reality.

...


=========================================================

Chevrolet Volt Plug-In Hybrid

http://www.chevrolet.com/electriccar/

IMAGINE: A DAILY COMMUTE WITHOUT USING A DROP OF GAS.

The extended-range electric vehicle is no longer just a rumor. We have put tremendous design and engineering resources in place to make this vehicle a reality.

The Concept Chevy Volt, with its revolutionary E-Flex Propulsion System will be different than any previous electric vehicle because it will use a lithium-ion battery with a variety of range-extending onboard power sources, including gas and, in some vehicles, E85
ethanol(1) to recharge the battery while driving.

When it comes to plugging in, the Volt will be designed to use a common 110–volt household plug. For someone who drives less than 40 miles a day, Chevy Volt will use zero gasoline and produce zero emissions.(2) For longer trips, Chevy Volt's range-extending power source kicks in to recharge the lithium-ion battery pack as required. We expect a driving range of an estimated 640 miles.(3)

...
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Old June 14th, 2008, 07:54 PM   #70
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The self-driving car might still be decades away, but the essential technologies are already available. The Department of Defense has funded a competition that has demonstrated the basic feasibility < http://www.darpa.mil/GRANDCHALLENGE/ >. I expect that self-driving weapons systems could appear within the next decade. I expect there will be legal hurdles that will prevent such a system from going into civilian use for several more decades, but ultimately it will prove safer to let a computer drive rather than an onboard human.

Regarding plug-in hybrids, General Motors plans to make one available through your local Chevrolet dealership by the end of 2010 < http://www.chevrolet.com/electriccar/ >. Toyota is developing a similar model. Nissan is developing an all electric version. I am sure the other automakers have their own variants in various states of design.
Indeed, and maybe we'll get one... by 2002! Oh, wait, by 2006! No, by 2010! Or by 2012! In fact, Toyota says all of its models will be hybrids by 2029!

Selling 50,000 plug-in hybrids a year will not do squat for us. It just helps drive sprawl.
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Old June 15th, 2008, 12:08 AM   #71
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Originally Posted by greg_christine View Post
The self-driving car might still be decades away, but the essential technologies are already available. The Department of Defense has funded a competition that has demonstrated the basic feasibility < http://www.darpa.mil/GRANDCHALLENGE/ >. I expect that self-driving weapons systems could appear within the next decade. I expect there will be legal hurdles that will prevent such a system from going into civilian use for several more decades, but ultimately it will prove safer to let a computer drive rather than an onboard human.

Regarding plug-in hybrids, General Motors plans to make one available through your local Chevrolet dealership by the end of 2010 < http://www.chevrolet.com/electriccar/ >. Toyota is developing a similar model. Nissan is developing an all electric version. I am sure the other automakers have their own variants in various states of design.
Greg, thanks for the links. I am fascinated by the work they're doing in automated driving systems. The fact that 6 cars finished that race unaided is amazing given the complexity of the problem. I still believe they are decades away from deploying it in cities, but they've come a long way.

As for plug-in hybrids, I'm kind of surprised they didn't make all hybrids plug-ins to begin with. They already had rechargeable batteries, so it would seem trivial to add a plug-in charger to completely avoid the ICE on short trips. It's nice to see they're finally coming around to it, but why did it take so long? Maybe there's some technical reason I'm missing...

Personally, I still prefer PRT even if automated/hybrid/electric automobiles become the norm. Automobiles may become more efficient, safe, clean, etc, but they will still clog up cities with street-level congestion and parking. PRT promises to eliminate both these problems by elevating the guideway and reusing the vehicles.
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Old June 15th, 2008, 04:59 PM   #72
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Transport Enthusiast,

The next generation of plug-in hybrids have been enabled by new battery technology. The evolution in battery technology has been very rapid. Each stage of the battery evolution has brought greater energy storage capacity per unit weight and volume. During the late 1990s, General Motors offered leases of the EV1, which was a two-seat all electric vehicle powered by lead-acid batteries. That technology was quickly overtaken by the hybrid technology offered in the Toyota Prius that combined a small gasoline engine with a nickel metal hydride battery. That technology is now being overtaken by lithium ion batteries. One of the companies at the center of this is A123 Systems < http://www.a123systems.com/ >. A123 Systems is one of the battery manufacturers participating in the development of the Chevrolet Volt < http://www.chevrolet.com/electriccar/ >.

Urban Ben,

According to APTA, light rail systems across the United States saw approximately 1.5 million boardings per week day during the first quarter of 2008. This translates to approximately 750,000 commuters using light rail. As of November 2007, Toyota had sold 510,000 Prius. Toyota offers several other hybrid models as do Ford, General Motors, Nissan, and Honda. It is quite possible that there are more commuters driving hybrids than there are commuters using light rail.

Even in cities with rail transit systems, it is forecast that auto traffic will continue to increase. A typical example is Seattle. During the campaign for the Sound Transit 2/RTID ballot measure, supporters acknowledged that auto traffic would continue to increase even with the expansion of the rail transit system. There is no possibility of addressing the issue of greenhouse gas emissions without developing new auto technology.

Regarding the problem of urban sprawl, rail transit can be a contributor. For instance, the Sounder commuter rail service in the Seattle area facilitates commutes for those who live at the northern and southern ends of the metropolitan region. If you look at the typical rail transit service for a large city, there is generally an in-town light rail or metro system combined with a commuter rail system. Commute distances by rail of 60 miles are not unusual.

I have concern that some of the measures now being enacted to fight sprawl will actually prove counterproductive. For instance, Seattle has raised height limits and relaxed parking requirements in many neighborhoods to encourage denser housing and fewer cars. The next generation of plug-in hybrids will require protected parking areas with access to electric power. This will not be a problem for the typical suburban household with a garage or carport. It could prove to be a major problem for those living in high-rises with no off-street parking.

- Greg V.
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Old June 15th, 2008, 06:59 PM   #73
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greg_christine, WSDOT shows decreased congestion on highways in the last year (presumably due to gas prices), and dramatically increasing transit use. Sounder service has seen a 30% year over year gain, prompting Sound Transit to add new cars sooner (we're seeing 1000+ people on trains with 840 seats).

You really don't understand that there's a big difference in congestion between ST2 and the no-build alternative, do you? In the I-5 corridor alone, you're talking about 170,000 trips daily on light rail, about 2/3 of what the highway's maximum capacity is - and that number assumes no TOD, no increase in density, and those models used $2 gas prices. Even the construction boom in Seattle in the last couple of years changes those projections.

Anyway, hybrid cars are a stopgap solution at best. Full EVs are better, but if a large portion of the US switched to plugging in, we'd have to raise the cost of energy or build significant new generating capacity to handle the load. That's fine, and it's better than gas engines (especially because replacing gas stations with higher uses helps increase density), but it's still going to be too expensive for the median income to use these vehicles like they use their cars today - they'll be good for short hops, like 20 miles, but not for 200 mile trips. Those we'll be doing on rail, like every other first world country...
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Old June 15th, 2008, 07:14 PM   #74
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And Greg... no, there is no evidence anywhere that rail transit "facilitates" sprawl in any way. The people driving to Sounder and taking it to Seattle already lived there. Nobody says "Oh, honey, if we lived here I could drive my car to a parking garage every morning, take Sounder, and get to work". That is exactly the kind of crap I've come to expect from you, though!
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Old June 16th, 2008, 03:31 AM   #75
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The Sounder Tacoma Dome station has 2410 parking spaces. The Sounder station in Everett has 481 parking spaces. Yes, people are driving to the Sounder stations and using the trains to commute to Seattle. Why wouldn't someone move to the areas surrounding Tacoma or Everett and take the train to Seattle if they can get a bigger house for a similar amount of money?

Regarding the impact that the Sound Transit 2 plan would have had on traffic congestion, the following is an extract from a guest editorial that ran in the Seattle Post-Intelligencer.

==========================================================
http://seattlepi.nwsource.com/opinio...64_rtid31.html

...

The Puget Sound Regional Council estimates that Sound Transit's full light rail plan will carry only 1.2 percent of all commuters by 2040 and traffic congestion simultaneously will rise 300 percent.

To look at it another way, Sound Transit will capture only about 14 percent of the predicted 1.2 million people expected to move into the region over the next 20 years.

Sound Transit's plan to spend $23 billion to move one-seventh of the region's projected population growth by 2030 is not only expensive, it is not even enough to reduce today's congestion at today's current population.

Most assume the RTID will handle the remaining 1 million people who will spill onto our already congested roadways. But with only one-third of the funding, the RTID package is unbalanced and does not even provide enough money for the region's most pressing road needs, the Evergreen Point Bridge and the Alaskan Way Viaduct.

Sound Transit itself says its $23 billion package will increase the overall share of travelers using public transportation only from 3.5 percent to 4 percent.

...

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Old June 16th, 2008, 05:53 AM   #76
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Not much more ecological than cars? Mass per passenger would be interesting here. The source for the electricity is also important. More people talk of getting rid of cars than making greener cars. But this is another discussion. Prt may never be the solution for everything or just too expensive but some people think only why it shouldn't function and make arguments without even thinking about possible solutions.

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- Station on/offs take longer than on fixed route, due to station selection and what have you, as well as the unhurried nature of personal systems. This drastically limits the capacity of any given "bay", making the number of bays at a station much higher, and increasing right of way costs.
This can be managed by designing a few second interval where people can enter. The pods could be already moving before people select their destination. If someone is too slow the pod could make a go around. After one such experience people will be pretty fast. Old people will have problems but younger generations can cope with this. ATM and online banking is horrid for someone. What about 2 lane stations where the slow granny is entering other people can enter their pods.

Headways? What about docking? Of course docking has to be made at slow speed else it negates the headway idea of it. If pods would be docked onto each other.This way mass of a single "vechicle" is increased but a rear collision is avoided when these things would travel at the same speed . Pods going to the other side of the prt city could either be docked or rerouted along less congested route to their destination. Also the idea of prt is not to stop at every station. Cars fail miserably during "rush hour" . Urban rails average speed drop alot with the frequent stops. Maybe some prt dreamers and advocated should forget about their wet dreams of motorway speeds without directly having to consider other traffic . Obviously a slower speed enables denser headways .

In the end maybe more bandwith is needed . I think this could be the financial bottle neck of these systems. Maybe really a lot of tunnels/routes are needed for this to work. Fallacy of imagining pods using the same urban/rail metro network when it's built for train sized vechicles. Pods are smaller than urbail rail so that would be an advantage. Traditional public transport fails when theres little traffic going to the same place at the same time, wait 15 min for train and 15 minutes also for the next train.

I begin to like the supplementing scenario where these pods would be an alternative for low traffic times or they could be used only when theres little traffic even on the normal urban rail routes and then be not in use during rush hour?
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Old June 16th, 2008, 08:05 AM   #77
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greg_christine, how much was gas when that article was written?

And for crying out loud, it calls the $10 billion package $23 billion. You can imagine the motivations of the person writing it.
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Old June 16th, 2008, 09:30 AM   #78
Shado
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Quote:
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(we're seeing 1000+ people on trains with 840 seats).
That's not particularly crowded. Crowded is when you have more people standing than able to sit. There you've got over 5 people sitting for every one standing, that's pretty spacious. Nothing like some trains that end up standing room only, or buses that at times are 'full' and can't let anyone else in them because the limit of physical space has been reached.
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Old June 16th, 2008, 06:41 PM   #79
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You could argue that you could elevate cars and they would take no room either.
No, I really don't think you can that argument. Elevated automobiles look like this:



Elevated PRT would look like this:



The amount of infrastructure required for a single elevated highway lane is an order of magnitude greater than that required for PRT. There really is no comparison.
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Old June 16th, 2008, 07:39 PM   #80
UrbanBen
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Excuse me, but that elevated highway carries an order of magnitude more people than that elevated PRT.

As for my 1000 people on 840 seat trains - these are bombardier bi-level coaches. They don't have much standing room, they're two by two seating with a narrow center aisle. The percentage of standees in a full car is quite variable between different designs - the Yamanote line E231 trains (the new ones) are called "cattle cars", the seating is all on the sides and is flipped up during rush hour.
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