Living Car Free - Opinions on Personal Rapid Transit.

Looking for opinions on Personal Rapid Transit,

http://en.wikipedia.org/wiki/Personal_rapid_transit
http://www.personalrapidtransit.com/

Have a look, tell me if you think it is a good idea or not and why.

I'm all for cycling, but i wouldn't expect everybody to want/be capable of cycling
everywhere/everywhen.

I think it's a good idea in an environment built around it -- which obviously doesn't exist.

The cost factors (comparisons to the cost of roads) are only really applicable if they are a replacement for roads, or if you can calculate an exact cost benefit. For example, "we can spend X m(b)illion on road expansion OR we can institute PRT.

The problems I see are much the same as those that affect other mass transit options. An incomplete system is of little use. Unfortunately, "complete" to many people means servicing the suburbs. My personal stance would be that any mass transit should serve the core completely first before worrying about the outlying areas. Unfortunately, getting this past the voters is almost impossible. As a result, cities like mine are paralyzed, incapable of doing anything other than building more roads.

I'm sure removing the humans from behind the wheel will be good. Fewer accidents, no road rage...

I think it's a good idea in an environment built around it -- which obviously doesn't exist.

The cost factors (comparisons to the cost of roads) are only really applicable if they are a replacement for roads, or if you can calculate an exact cost benefit. For example, "we can spend X m(b)illion on road expansion OR we can institute PRT.

The problems I see are much the same as those that affect other mass transit options. An incomplete system is of little use. Unfortunately, "complete" to many people means servicing the suburbs. My personal stance would be that any mass transit should serve the core completely first before worrying about the outlying areas. Unfortunately, getting this past the voters is almost impossible. As a result, cities like mine are paralyzed, incapable of doing anything other than building more roads.

Why would it be unable to add to a road system? Most of the proposed systems involve light overhead rail which can share roadways.

Agreed that it would have to cover an reasonable area before it became useful, but once you have say, downtown covered, why could you then not add sections as desired? I think of this as a replacement/alternative for something between buses and taxis.

I'm sure removing the humans from behind the wheel will be good. Fewer accidents, no road rage...

I definitely agree, I think we may be in a minority though. I fear one sticking point would be distrust of automated systems.

I would love to have one of these systems in operation in every town. With computer chips so fast and inexpensive these days, coupled with the radar technology used by some automobiles for automated parking, this would seem to be an ideal solution for the people who won't ride mass transit because of associating with people they find distasteful. Since the systems would be 2-5 times faster than bus service and even faster than private automobiles in rush hour, there would be few excuses for not utilizing such a system.

Such systems would easily be expandable with the advent of GPS or other sensors in the roadbed. Connecting new segments would be very easy to do.

In the second link in the first post there is a presentation of PRT. At the end of it there is an image of a passenger in one of the modules with his full size bicycle. That is a great combination of transit modes.

It would be great if these were linked throughout the USA and Canada. Imagine swiping a credit or debit card and taking ones own little pod to another city. One could transfer into the next cities system and continue to the next city beyond that until the final destination is reached. It would almost be door to door service.

The only people who would be afraid of using an automated PRT system are people who are afraid of using elevators. Most of us use elevators at one time or another. They are probably the most widely used automated people transportation system in the world. I have been stuck in elevators three times. Two of those times I had to force the doors open and climb up about four feet to get out. The other time the elevator just sunk to the basement because it was overloaded. The doors needed to be forced open then too. I still ride elevators and rarely even remember those times I was stuck.

Bring on the PRT!

In terms of energy efficiency, I don't see how the PRT would be much different than a private car. I guess it could be programmed to take the most direct route, and there wouldn't be any stop and go, but I don't see any other efficiencies. What am I missing?

The Wikipedia site explains that a PRT unit should weigh no more than 600 pounds and carry three or less people. The unneeded cars just stay parked until someone requests one. Since the pods don't travel unless in use or when being sent to the busy section during peak hours they average a higher average occupancy than busses. These things combine to make it twice as efficient as a bus running at full capacity.

Busses often run almost empty in the off peak hours which makes them very inefficient. Surely if everyone rode mass transit instead of using cars the busses would be more efficient, but that won't happen (in the USA).

They are different in weight and propulsion. To keep weight down, they use small electric motors with no batteries.

These would also work well to connect the "outside ends of the spokes" to compliment existing mass transit systems, rather than forcing a trip downtown before you get to your destination.

The overhead design makes routing flexible and inexpensive, and doesn't create crossing barriers like light rail does. Overall system cost should be competitive with a new buss routes when road wear and liability are factored in.

Bike racks are a must though!

The idea has been kicked around for decades, but a fully functional one has yet to be built. The closest thing is the one in Morgantown, and even that is not a pure PRT. Let's see how one works in practice before making a judgment one way or the other.

It's fine, as long as it moves very slowly, never, ever hits anybody, and I don't have to pay for it.
I don't pay for fat peoples, cripples, or old people's cars now, I don't want to pay for thesethings either.

Looking for opinions on Personal Rapid Transit,,,,

Have a look, tell me if you think it is a good idea or not and why...
It's a bad idea, because it's trying to combine two opposite transportation schemes: mass-transit and individual-transit.

Mass transit is only valuable when you have a lot of people who want to travel between (roughly) the same places, and in practice it becomes less efficient the more places that it covers.

Big urban areas have this problem of transportation--you always see the problem of urban mass-transportation systems running mostly-empty. Also the peak use is only at two times, and isn't symmetrical--because of people commuting in to the city in the mornings, and going outbound at night--so any mass-transit system is going to be running basically half-empty even at peak-use times, and very-much-less than half-empty the rest of the time.

So the question of efficiency then becomes: what mass-transit system is cheapest to run at low capacity? And the answer is..... roads. Like, for automobiles. Those automobiles could be gasoline powered, or electric, or whatever--but the reason that roadways are the "cheaper" form of transportation to put in, is because a large part of the cost of them is borne by the individual, in that the individual has to buy their own car. And the individual has a wide variety of choice in how expensive of a vehicle to buy, or even to not buy a vehicle at all.

Cities don't have room for more roads, at least at ground level. So the better answer here is to either start building muti-level roads, or to force urban areas to spread out more (perhaps by taxing employers highly per-person, to drive big employers out of urban areas).

What urban areas NEED is a small inexpensive enclosed trike with climate control, with only one or two-person capacity, powered by a small gasoline engine of 250cc's or less. These would put less wear on roads, less pollution and less parking space needed but would still allow individuals to travel independently. ....We have motorcycles now, but they're not attractive in anything but mild weather, and even then they have drawbacks (mostly they have no good lockable storage or climate control).
~

Cities don't have room for more roads, at least at ground level. So the better answer here is to either start building muti-level roads, or to force urban areas to spread out more (perhaps by taxing employers highly per-person, to drive big employers out of urban areas).
~

This is the first time I've ever heard someone advocate sprawl as a solution to congestion. I have to say, I think this is one of the worst ideas I've ever heard.

Transportation costs get increasingly more expensive the further from center you move.

I don't pay for fat peoples, cripples, or old people's cars now, I don't want to pay for thesethings either.

Thank you, Mr. Scrooge.

A decent mass-transit system is one of the amenities of urban living, along with sewers, roads, piped-in water and gas, etc. What form it should take in a particular community is a matter of debate.

This is the first time I've ever heard someone advocate sprawl as a solution to congestion. I have to say, I think this is one of the worst ideas I've ever heard.
The question is, would it work or not?


Transportation costs get increasingly more expensive the further from center you move.
Further from the center of what?

The problem of congestion is people trying to get to their jobs,,, of people not being able to live close to their jobs to make things like bicycling practical--and it's mostly only urban areas that suffer the problems of congestion. You can move the people, or move the jobs.
~

Why don't you see a drawing of one of those things above freeways or next to power lines (high voltage).

Sprawl where I live is Economy.

Thank you, Mr. Scrooge.

A decent mass-transit system is one of the amenities of urban living, along with sewers, roads, piped-in water and gas, etc. What form it should take in a particular community is a matter of debate.

But this really isn't mass transit. This is personal transit. I don't mind paying for the roads, I don't mind paying for a cab when I'm in it, paying for a bus when I'm on it, but I'm not paying for somebody else's persoanl transit.

After think about this a while, this system seems to me like a public transportation concept with private accommodation aboard... sort of if you had private compartments aboard the bus. I say this because:
1. I don't see how you could go completely from any point to any other point in the city. You would have to get off at some kind of stop and then hoof it to your destination.
2. You would probably have to wait to be "scheduled" to avoid any massive traffic tie-up.

Sounds like a bus to me.

The system sounds marginally better than everyone owning and driving a car, but I doubt it would be that good if everyone gave up the car and relied on the PRT system. A better solution would be to get rid of cars and let everyone walk or ride bicycles....

The system sounds marginally better than everyone owning and driving a car, but I doubt it would be that good if everyone gave up the car and relied on the PRT system. A better solution would be to get rid of cars and let everyone walk or ride bicycles....

And what of those who are physically incapable of riding bicycles, or live in terrains or climates unsuitable for cycling, or have to carry loads to heavy or bulky for bicycles, or travel longer distances than are practical on a bicycle, or some combination of the above?

In terms of energy efficiency, I don't see how the PRT would be much different than a private car. I guess it could be programmed to take the most direct route, and there wouldn't be any stop and go, but I don't see any other efficiencies. What am I missing?

You have answered most of the question already, no stop and go direct route, no delays except for possibly some at very popular drops/pickups. For example, currently my commute takes about an hour by bus or bike, if I had a car it would be 25 minutes on a good day, averaging 30 minutes maybe with the potential in bad traffic or weather of up to 90 minutes. PRT would be 15-20 minutes with a high reliability factor. Pollution would be dependent on the source for the electricity so could be clean.Energy consumption should be anything from 1/3 to 2/3 that of most other transit systems on a passenger mile basis and much lower than an IC car. Noise pollution is at the level of a golf cart. High density drops/pickups could be taken care of by larger stations with multiple access routes.e.g. at sports stadiums, malls, connections to long distance transit options etc.

The big advantage as I see it, no schedules, anytime I want to go, I walk to the nearest stop and call a pod.

They are different in weight and propulsion. To keep weight down, they use small electric motors with no batteries.

These would also work well to connect the "outside ends of the spokes" to compliment existing mass transit systems, rather than forcing a trip downtown before you get to your destination.

The overhead design makes routing flexible and inexpensive, and doesn't create crossing barriers like light rail does. Overall system cost should be competitive with a new buss routes when road wear and liability are factored in.

Bike racks are a must though!

Most of the popular designs are big enough for 2 adults with bikes. See the second link and follow the presentation and it shows a guy with a bike in the pod.

It's fine, as long as it moves very slowly, never, ever hits anybody, and I don't have to pay for it.
I don't pay for fat peoples, cripples, or old people's cars now, I don't want to pay for thesethings either.

Do you live in a city with transit services now? That is any good? Chances are your taxes are subsidizing it. This system should be efficient enough to run revenue neutral or possibly at a profit. If it is overhead, it couldn't hit anything.There are new risks involved, which is one of the sticking points, but overall the risk should be lower than current systems.

The idea has been kicked around for decades, but a fully functional one has yet to be built. The closest thing is the one in Morgantown, and even that is not a pure PRT. Let's see how one works in practice before making a judgment one way or the other.

You have hit the big one on the head. Chicken and egg, I think the first proper PRT will be in Scandinavia or Japan. Once it is in and working, I think the city involved will be swamped by fact-finding visits by other cities. People en-mass tend to be too comfortable with the status quo.

It's a bad idea, because it's trying to combine two opposite transportation schemes: mass-transit and individual-transit.

Mass transit is only valuable when you have a lot of people who want to travel between (roughly) the same places, and in practice it becomes less efficient the more places that it covers.

Big urban areas have this problem of transportation--you always see the problem of urban mass-transportation systems running mostly-empty. Also the peak use is only at two times, and isn't symmetrical--because of people commuting in to the city in the mornings, and going outbound at night--so any mass-transit system is going to be running basically half-empty even at peak-use times, and very-much-less than half-empty the rest of the time.

So the question of efficiency then becomes: what mass-transit system is cheapest to run at low capacity? And the answer is..... roads. Like, for automobiles. Those automobiles could be gasoline powered, or electric, or whatever--but the reason that roadways are the "cheaper" form of transportation to put in, is because a large part of the cost of them is borne by the individual, in that the individual has to buy their own car. And the individual has a wide variety of choice in how expensive of a vehicle to buy, or even to not buy a vehicle at all.

Cities don't have room for more roads, at least at ground level. So the better answer here is to either start building muti-level roads, or to force urban areas to spread out more (perhaps by taxing employers highly per-person, to drive big employers out of urban areas).

What urban areas NEED is a small inexpensive enclosed trike with climate control, with only one or two-person capacity, powered by a small gasoline engine of 250cc's or less. These would put less wear on roads, less pollution and less parking space needed but would still allow individuals to travel independently. ....We have motorcycles now, but they're not attractive in anything but mild weather, and even then they have drawbacks (mostly they have no good lockable storage or climate control).
~

I partially agree with you, it does allow you you private use of a pod, this is where I think it will increase substantially rider numbers. The transit where I live is... not too bad, but i still end up getting jammed in with packs of people, some of who don't have as intimate a relationship with soap as one would like. The peak use problem doesn't go away, but simulations have shown PRT works better than anything else, by a large margin. I've just started playing with this free simulation tool, I'll report back if I can get any meaningful results.

http://faculty.washington.edu/jbs/itrans/simu.htm

A light trike is something I might buy, but a lot of people in North America wouldn't dream of driving in a Smart, what makes you think they would go for something smaller? I do think they will start to appear in increasing numbers as the fuel problems start to become more obvious, but a PRT allows you to sidestep a lot of the problem. Nothing is perfect but I think this comes closer than other proposed solutions.

Edit: Missed some of your points, I couldn't get back to this for a couple of days and there are a lot of points to consider.

If you look at the way the system operates, it eliminates the spoke and hub and transfer problems of light rail/bus/trolley transit. Its a grid, a somewhat poor analogy is to consider railway or going further back, stagecoaches, as the equivalent of the telegraph, city buses or light rail could be compared to a telephone, PRT could be likened to the internet. As far as your comment about allowing urban areas to spread out, are you advocating more sprawl, or do you want to see outlying areas become more self sufficient? Work, shop, play in the same "village"?

Everyone's talking political, financial and technical; and I'm finding the subject and technology fascinating. I'd like to hit it from another angle - behavioral. And it's not going to be pretty.

The biggest negative I'm seeing is nobody owns these individual transportation modules (brings back a line from Bowie's "Jean Genie"), so nobody has any particular interest in seeing that they're cared for - of course the answer is paid custodial staff, which is not going to be cheap.

Bad case situation: You plan on going to church Sunday morning, meet a module only to discover someone has peed/shat/puked in it Saturday night. Or spent the evening f***ing in it. And there you are in your Sunday best.

How does one keep a homeless person from camping out in one - seems like they'd be the ultimate grocery cart?

Wost case situation: In a high crime area, it's a wonderful place to dispose of a body, or at least perpetrate a mugging.

Even not going to those extremes, we're talking garbage collecting in them, and unlike a subway you're not running them on a set schdule where a cleaning crew can pre-plan a meeting point and time to do maintenance. I'm guessing cleaning and maintenance would be more expensive than on a scheduled, limited use line.

Just something to think about. All those technical based thoughts invariably underestimate the human ability to screw up the engineers dreams. A good example: Remember all those dreams of interstate highways being fast moving corridors for going long distance? Of course they were. In an engineer's/futurist's mind, you didn't get on one to go to the other side of town - you stayed on the local roads. You only used them to go across the state, or multiple states.

Didn't quite work that way, did it? Expect the same kind of human bollixing on a system like this, and try to plan for it. I can see it possibly working in Japan, because the Japanese are regimented enough to minimize (note: not do away with) such problematic behavior.

And what of those who are physically incapable of riding bicycles, or live in terrains or climates unsuitable for cycling, or have to carry loads to heavy or bulky for bicycles, or travel longer distances than are practical on a bicycle, or some combination of the above?

Or, for that matter, don't WANT to ride a bicycle due to the exertion involved? I'm thinking in terms of America, and I'll have serious problems of someone mandating to me that my bicycle is my main mode of transportation - assuming other possibilities are out there and working.

The question is, would it work or not?


Further from the center of what?

The problem of congestion is people trying to get to their jobs,,, of people not being able to live close to their jobs to make things like bicycling practical--and it's mostly only urban areas that suffer the problems of congestion. You can move the people, or move the jobs.
~

Ah, you are advocating a more independent "identity?" for the suburbs, this has potential as well. PRT could still work in such "islands" and could be used to connect the City heart to the suburbs, you couldn't expect every suburb to have their own ball team, ballet theater ( to grab an example out the air ) etc.

Why don't you see a drawing of one of those things above freeways or next to power lines (high voltage).

Sprawl where I live is Economy.

Not sure what your point is....? There are limitations on where you could put these, yes. I can think of a few myself. I think when one of these systems proves itself you will see some "district" that couldn't get it because of some technical or other problem, the residents will start to agitate for fixing the "problem"

But this really isn't mass transit. This is personal transit. I don't mind paying for the roads, I don't mind paying for a cab when I'm in it, paying for a bus when I'm on it, but I'm not paying for somebody else's persoanl transit.

But if you are paying taxes to support a transit system now, what is the problem with having a better, cheaper system that you might want to use? EDIT: that might pay for itself, which darn few current ones do.

After think about this a while, this system seems to me like a public transportation concept with private accommodation aboard... sort of if you had private compartments aboard the bus. I say this because:
1. I don't see how you could go completely from any point to any other point in the city. You would have to get off at some kind of stop and then hoof it to your destination.
2. You would probably have to wait to be "scheduled" to avoid any massive traffic tie-up.

Sounds like a bus to me.

A bus with no schedule and no fixed route. I currently walk past a bus stop 40 yards from my door and walk about 1/3 mile to a different stop , because the first stop is served by a route that would take 40 minutes longer with connections.

It's not a taxi service but it isn't far off, and it certainly isn't a bus. Simulations show PRT is subject to much less congestion problems than other systems. This is key, you see line ups at transit stops mostly because you are tied to the schedule and route.

The system sounds marginally better than everyone owning and driving a car, but I doubt it would be that good if everyone gave up the car and relied on the PRT system. A better solution would be to get rid of cars and let everyone walk or ride bicycles....

How? In -10F snow, rain, with a broken leg, etc. etc, etc.How about your Grannie who doesn't get around so well? Should she stay in the supported care place? Such place could build a covered station inside. You can guarantee the malls would be putting in big stations. I would love to see more people riding/walking, this may increase or decrease that, probably a bit of both ( that is, I might exercise less, others may get more simply from walking to the station )

Everyone's talking political, financial and technical; and I'm finding the subject and technology fascinating. I'd like to hit it from another angle - behavioral. And it's not going to be pretty.

The biggest negative I'm seeing is nobody owns these individual transportation modules (brings back a line from Bowie's "Jean Genie"), so nobody has any particular interest in seeing that they're cared for - of course the answer is paid custodial staff, which is not going to be cheap.

Bad case situation: You plan on going to church Sunday morning, meet a module only to discover someone has peed/shat/puked in it Saturday night. Or spent the evening f***ing in it. And there you are in your Sunday best.

How does one keep a homeless person from camping out in one - seems like they'd be the ultimate grocery cart?

Wost case situation: In a high crime area, it's a wonderful place to dispose of a body, or at least perpetrate a mugging.

Even not going to those extremes, we're talking garbage collecting in them, and unlike a subway you're not running them on a set schdule where a cleaning crew can pre-plan a meeting point and time to do maintenance. I'm guessing cleaning and maintenance would be more expensive than on a scheduled, limited use line.

Just something to think about. All those technical based thoughts invariably underestimate the human ability to screw up the engineers dreams. A good example: Remember all those dreams of interstate highways being fast moving corridors for going long distance? Of course they were. In an engineer's/futurist's mind, you didn't get on one to go to the other side of town - you stayed on the local roads. You only used them to go across the state, or multiple states.

Didn't quite work that way, did it? Expect the same kind of human bollixing on a system like this, and try to plan for it. I can see it possibly working in Japan, because the Japanese are regimented enough to minimize (note: not do away with) such problematic behavior.

Yes, most solutions to that involve 2 way remote communication/monitoring of the stations and short term video surveillance in the pods i.e. it is for the most part not watched, but if a pod arrives at station in dirty condition, ( not talking couple of gum wrappers here ) you press a button to reject it, and the last 1/2 hour or so is stored for review to identify the culprit and a another pod is summoned while the first goes off to be cleaned.

There are going to be unforeseen problems, I don't think that's a reason not to try it. EDIT: thats one of the reasons I started this thread, to bring up new viewpoints and potential problems so solutions can be suggested.

Yes, most solutions to that involve 2 way remote communication/monitoring of the stations and short term video surveillance in the pods i.e. it is for the most part not watched, but if a pod arrives at station in dirty condition, ( not talking couple of gum wrappers here ) you press a button to reject it, and the last 1/2 hour or so is stored for review to identify the culprit and a another pod is summoned while the first goes off to be cleaned.

There are going to be unforeseen problems, I don't think that's a reason not to try it. EDIT: thats one of the reasons I started this thread, to bring up new viewpoints and potential problems so solutions can be suggested.

Don't take my comments as being in the "don't try it, too much trouble" school. Quite the contrary, I love the concept.

However, we tend to underestimate what can go wrong with these dreams, always looking at working technical solutions and quietly figuring that people will behave like their 'supposed' to in relation to the solution. It don't work that way. People are ornery.

I'll toss another one at you: I'll bet that among youths, it would become a neat game to derail or jam the modules. Why? Why not? Who needs a good reason, it's Friday night and I'm bored?

Don't take my comments as being in the "don't try it, too much trouble" school. Quite the contrary, I love the concept.

However, we tend to underestimate what can go wrong with these dreams, always looking at working technical solutions and quietly figuring that people will behave like their 'supposed' to in relation to the solution. It don't work that way. People are ornery.

I'll toss another one at you: I'll bet that among youths, it would become a neat game to derail or jam the modules. Why? Why not? Who needs a good reason, it's Friday night and I'm bored?

Not at all, I like the fact I'm getting some feedback and people are thinking about it. I might not be so happy if someone comes up with a showstopper. :p I'm trying not to let my enthusiasm for this idea lead me to being "religious" about it.

If you look through the second link in my OP, you'll see some pictures of the underlying construction. My own opinion is that they would be very difficult to derail, jamming? possibly, with remote
monitoring ( with IR sensors? ) you could minimize the possibilities. Terrorism? Individual pods would have 2-4 people on board, there are bigger targets. A big enough impact to tear out a support pole? it would be 50-50 if it dumped a pod and if the truck could take out a pole, it could take out a bus.

................. People are ornery...............


"A person is smart. People are dumb, panicky dangerous animals and you know it." Kay, MIB (original)
Possibly the best movie quote ever. :D

I don't see why these things are really necessary. Assuming public transportation could actually work well, that would probably be enough to get most people to use it. When I was in London, I had fairly good luck with the Underground system, and was able to get from A to B pretty quickly. I didn't have any real desire to drive anywhere, and I like cars. I did miss my bike though.

This PRT business sounds like a really expensive way of getting about. Assume the PRT systems do catch on, and people take preference to them over having their own car or bike, or using buses or an underground. They'll get congested, there won't be enough pods to deal with demand, or a combination of the two. Not to mention that, unlike escalators, you really would have no way of knowing where you'd end up. A glitch in the routing system could easily bring the whole thing to it's knees. It doesn't seem like a particularly good idea, or at least not for the amount of money it'd cost to build such a system.

Here are a couple of links of opposing views. I am currently ambivalent on them, but figure they would end up like any other goverment backed project...half assed and over budget:rolleyes: If money was spent on getting mass transit up to par in most larger metro areas I don't think a PRT would be as necessary. On some fronts I think they are developing something to answer an issue that could be covered by other methods of transit.

As an alternate we could stick everybody in small electric 2-4 passenger cars with computer controls and allow them to use specially marked highways. That technology already exists and could be used with existing infrastructure, ie; toll roads. But it has it's own set of issues.

http://faculty.washington.edu/jbs/itrans/vuchic1.htm

http://www.lightrailnow.org/facts/fa_prt001.htm

Aaron:)

Ah, you are advocating a more independent "identity?" for the suburbs, this has potential as well. PRT could still work in such "islands" and could be used to connect the City heart to the suburbs, you couldn't expect every suburb to have their own ball team, ballet theater ( to grab an example out the air ) etc.
Is the question of the PRT one of improving transportation efficiency? Or of preserving high-population-density areas as comfortably as possible?

The typical transportation efficiency problem that cities have is one of peak use, not of total capacity. The problem is the same no matter what vehicle type you're considering--cars, regular trains or PRT's.

Forcing larger employers out of urban areas is the only way to reduce the peak-use problem.
~

"A person is smart. People are dumb, panicky dangerous animals and you know it." Kay, MIB (original)
Possibly the best movie quote ever. :D

Yep - and I've never seen a system, no matter how well designed, that a person can't subvert. Often in incredibly interesting ways that the original designers would never think of, not in a million years. Every time you come up with a correction for the last prank, someone will think up a way to trump your efforts.

You've got to assume that somewhere, someone is going to do something that takes that well thought out system one is so enthusiastic about and turns it into a malfunctioning piece of under-designed trash. My example of the Interstate system is one of the best examples ever, and that one was done with absolutely no malicious intent on the part of the users - yet it still managed to turn a nice dream into a nasty piece of reality (I live near the I-95 corridor north of Richmond).

This is not a reason to drop the idea - it's just a warning that the system isn't going to work nearly as well as a proponent thinks it will.

I don't see why these things are really necessary. Assuming public transportation could actually work well, that would probably be enough to get most people to use it. When I was in London, I had fairly good luck with the Underground system, and was able to get from A to B pretty quickly. I didn't have any real desire to drive anywhere, and I like cars. I did miss my bike though.

This PRT business sounds like a really expensive way of getting about. Assume the PRT systems do catch on, and people take preference to them over having their own car or bike, or using buses or an underground. They'll get congested, there won't be enough pods to deal with demand, or a combination of the two. Not to mention that, unlike escalators, you really would have no way of knowing where you'd end up. A glitch in the routing system could easily bring the whole thing to it's knees. It doesn't seem like a particularly good idea, or at least not for the amount of money it'd cost to build such a system.

How were you using the Underground? For commuting in rush hour, I have used it. It did work, it was not pleasant, I used it only because there was no reasonable alternative. It's been a while, I suppose it might have improved.

Cost, I don't have the figures to hand, but the comparison of Underground conventional rail versus light overhead are huge in terms of $/mile. PRT would need many more miles, yes, but it replaces buses as well. Have you seen the cost of new buses? $1m a pop is not uncommon.

I'll bet that among youths, it would become a neat game to derail or jam the modules. Why? Why not? Who needs a good reason, it's Friday night and I'm bored?I'm not so sure. For example, it would already be easy enough to pile stuff on train tracks and "enjoy" the potentially spectacular results on a boring Friday night. That doesn't happen much, at least not around here. I don't know why, but it doesn't.

--J

Is the question of the PRT one of improving transportation efficiency? Or of preserving high-population-density areas as comfortably as possible?

The typical transportation efficiency problem that cities have is one of peak use, not of total capacity. The problem is the same no matter what vehicle type you're considering--cars, regular trains or PRT's.

Forcing larger employers out of urban areas is the only way to reduce the peak-use problem.
~

I suppose you could say it's making it more comfortable. How would you go about forcing employers out to the suburbs? How quick could you do it? How do you deal with fairly high density situations that already exist? Here's a thought, A factory or office block would probably find it hard to get a transit company to shift their schedules to allow different start/finish times, but with PRT, if 3 or 4 closely located companies were finding their workers were running into congestion delays, it would be fairly trivial to arrange stepped shifts, even 15-30 minutes could make a big difference.

Again, one fairly important reason you get congestion on bus and particularly light rail systems, is that you can only run so many routes. With PRT the number is a function of how many permutations the grid allows. When I get off my first bus, the crowd splits roughly into 3, they don't all want to get off at that point, it's forced on them by the need to make connections or the fact that thats the closest point that paticular bus route serves.

Here are a couple of links of opposing views. I am currently ambivalent on them, but figure they would end up like any other goverment backed project...half assed and over budget:rolleyes: If money was spent on getting mass transit up to par in most larger metro areas I don't think a PRT would be as necessary. On some fronts I think they are developing something to answer an issue that could be covered by other methods of transit.

As an alternate we could stick everybody in small electric 2-4 passenger cars with computer controls and allow them to use specially marked highways. That technology already exists and could be used with existing infrastructure, ie; toll roads. But it has it's own set of issues.

http://faculty.washington.edu/jbs/itrans/vuchic1.htm

http://www.lightrailnow.org/facts/fa_prt001.htm

Aaron:)

How much do you want to spend? I've been digging around for some reasonably accurate figures for our local service, so far I have a total running cost for the light rail of $40m/year, can't find anything for the buses but the revenue for both is about $90m/year. I would guess the buses soak up about 3 times as much as the train, which corresponds well to a statement I read ( unconfirmed ) of a tax subsidy of 50-55%

This does not include capital cost, the light rail has cost over 1/2 Billion so far over 25 years or so, and they have just earmarked another 1/2$B for an expansion of approximately 10%

I dread a typical government boondoggle, Morgantown is apparently working fairly well these days, despite design by committee problems to start with.

If you are going to use the same system, ( small electric cars under computer control ) why would you leave it at grade? In conflict with other traffic? And how do you fit new roads with wire guides or whatever in a dense city environment?

Your links have many points against PRT, I'm not going to answer them all, but I'll take one from each and respond, if you think one of their points seems particularly cogent, bring it up and I'll try to answer.

"Transportation systems with guideways (rail, monorail, or other technology), stations and sophisticated automation require substantial investment costs." More than Light rail? Look at the guideway and pod shown on the Taxi 2000 website, now go look at the gravel bed, rail links, signaling equipment, rolling stock, overhead power lines etc etc of your local "light" rail. If you're really lucky, you might see them doing maintenance.

From the second link.
"More and more, fire departments and other emergency service providers are requiring elevated guideway systems, such as monorails, to be equipped with emergency evacuation walkways, wide enough for wheelchairs. Such walkways would undoubtedly enlarge the profile of PRT guideway structures, increasing the impact of visual intrusion." I picked this one because it seemed to me to be the only one that has any significant merit. Yes, such a thing would be an eyesore, a modern, efficient PRT system is only going to be built where the local and regional governments is sufficiently flexible to realize what rules need to be adapted or rewritten. For example, allowing for failure of a redundant power feed to the network, one might put in small batteries, just enough to get the pods to the next stop, say 3/4 mile? High lift maintenance trucks, something like a cross between a power company cherry picker and an airport mobile stair could deal with people stuck in a frozen pod or one stuck due to traffic impact on a support pole. You would have a few of these around to deal with repairs and extending the system.

I got the impression the second link "lightrailnow" has a bit of an axe to grind, they were pushing light rail very heavily in Texas. They manged to get a light rail system installed in Houston, it is not the most successful transit system ever. I read somewhere, can't track it down at the moment, that one year they averaged 65 accidents per year per mile of track. :eek:

I got the impression the second link "lightrailnow" has a bit of an axe to grind, they were pushing light rail very heavily in Texas. They manged to get a light rail system installed in Houston, it is not the most successful transit system ever. I read somewhere, can't track it down at the moment, that one year they averaged 65 accidents per year per mile of track. :eek:

Hmm, apparently my memory was faulty.

Any way you look at it, Houston's drivers are collectively among the nation's worst. And nowhere is this fact any more evident than along the city's new 7.5-mile light rail line. According to the Houston Chronicle of January 17, 2005, there were 63 collisions last year (2004) between cars and light rail trains along the corridor – and "more than two-thirds were caused by motorists making illegal turns or running red lights." (Several other accidents have involved pedestrians.) This translates into a collision rate that is about 25 times the national average for light rail systems, according to the Federal Transit Administration. While several other cities, such as San Jose, Portland, Boston, New Orleans, Denver, and Salt Lake City, all have street-running light rail and streetcar systems, drivers in those cities for the most part seem to be able to avoid crashing into their trains. Unfortunately, that's not the case in Houston. The propensity of local drivers to smack into the new train system has even become national news.

That was from the lightrailnow site. They then go on to lambaste, quite properly in my opinion, the standard of driving in Houston. It does however, highlight the advantages to a system at a safe distance above ground.

http://www.youtube.com/watch?v=CV2rdGX4JYc

Pretty awful driving.

From the second link.
"More and more, fire departments and other emergency service providers are requiring elevated guideway systems, such as monorails, to be equipped with emergency evacuation walkways, wide enough for wheelchairs. Such walkways would undoubtedly enlarge the profile of PRT guideway structures, increasing the impact of visual intrusion." I picked this one because it seemed to me to be the only one that has any significant merit.

I hadn't thought of that. Everything breaks down. Imagine trying to get to somebody suffering a heart attack while stuck up there.

Anyway, watching the PRT website made me think of a particular Simpsons episode:
http://en.wikipedia.org/wiki/Marge_vs._the_Monorail
:D

coldfeet,
I posted the links as an opening to discussion and alternate views. I agree that LightRailNow probably does have an axe to grind.

My view is that ALL means of transit is subsidized...even cycling to an extent. About the only form of transit that isn't is walking. Public transit everywhere is heavily subsidized, we just have to decide where we want the money spent, on roadways clogged with oversize polluting vehicles with a single occupant, street level light rail, alternate fuel buses, monorails or the transportation of your choice. With buses and light rail it is possible to use existing infrastructure that for the most part is already paid for to a certain extent.

FWIW my take on the computer controlled car is based on a demo tape I saw many years ago from Honda, they had developed a system utilizing small video cameras and a wirless system where the video cameras keyed off of the pavement striping, then they had 4 sided sensors to control distance between the vehicles. In the tape they had 6 or 8 Honda Accords lapping a closed course test track at 120kph with only about 2' between the vehicles, the drivers were on board but were holding their hands in the air. IIRC the cost per vehicle at the time was around $1000usd. People spend a helluva lot more than that on entertainment devices for their cars. The roadways would require only minimal upgrades for the system to work effectively.

I believe that the biggest problem is that too many people are looking for a one size fits all solution, and it doesn't exist. The current automotive culture is proof of that. Unfortunately as Skyerocker has pointed out people can be quite ornery if forced to change. Some can and do look forward to new experiences and are willing to try something new.

I would like to see road based traffic curtailed in exchange for more affordable walkable locales and better overall mass transit. Higher speed trains to replace interstate travel and short haul airline flights, urban rail between smaller outlying towns and major cities. Perhaps PRT has a place in the mix, but I don't see it in the current urban setting that they are pushing. You are looking at a totally new investment in infrastructure vs utilizing the partial that already exists in many cases for buses and light rail.

Aaron:)

I suppose you could say it's making it more comfortable. How would you go about forcing employers out to the suburbs? How quick could you do it? How do you deal with fairly high density situations that already exist? Here's a thought, A factory or office block would probably find it hard to get a transit company to shift their schedules to allow different start/finish times, but with PRT, if 3 or 4 closely located companies were finding their workers were running into congestion delays, it would be fairly trivial to arrange stepped shifts, even 15-30 minutes could make a big difference.
The problem with this is that businesses don't do it now. Some have flex-time, but most don't. Many businesses need to be able to interact with other businesses open during the same hours, and a 30-minute shift likely wouldn't accomplish much anyway. How long is the rush hour in your town? In St Louis it's about 1.5 hours, when the weather is good.

The easy-sensible way would be as I said--to place a progressive tax on employee headcounts. If a large business in the center of a city is heavily contributing to the local transit systems being overwhelmed, then that causes others losses, in the way of gasoline and pollution generated by gridlocked traffic. If a big employer wants to stay in the middle of the city and pay the tax anyway, that's their choice. It doesn't force them to do anything, in any way that's not legal now.


Again, one fairly important reason you get congestion on bus and particularly light rail systems, is that you can only run so many routes. With PRT the number is a function of how many permutations the grid allows....
Yea, but you are assuming that there would always be people who wanted to make use of every possible trip, all the time, and there won't be--for the same reasons we have rush-hours now.

Too many employers in too small of an area is what causes peak-use problems. The PRT would cost a lot of money, and do nothing to reduce peak-use problems.

I would even go so far as to say that if you wanted a city to become sustainable, then you should get rid of all the public transportation systems. They cost huge sums of money, and are run far below capacity most of the time.
~

http://en.wikipedia.org/wiki/Morgantown_Personal_Rapid_Transit

This is about the closest thing to a PRT that has yet been built; it seems to work well, but the WVU campus is a situation with rather unusual, if not unique, features, and I am not sure if it really is suitable for too many other places.

These responses are good, if you are following along, can I ask you to pay attention to all the various threads? PRT has many different aspects, and the tendency I have seen is to focus on one aspect and miss the fact that because of the nature of PRT, it may not be as important as for other forms of transit.

Thank You for all being so well mannered. (even if you think I'm full of it) :)