Friday, July 14, 2006

Getting around...

Did you read Evan’s proposal for bringing the Metro to HoCo? If not, do it now and come back for my (brief) take, which is:

I like the concept behind it, even though the realist (pessimist?) side of me thought it was too ambitious. Specifically, the aspect I like most is the idea of a local circulatory system that connects to the broader regional system. This provides benefits for short- and long-range commuters, as well as those who need to just get around town. Our existing system is somewhat like this, but both our in- and out-of-town options (buses and a couple commuter trains) are limited and certainly less convenient than a subway.

While I firmly support bringing the Metro to Columbia (or at least something akin to real public transportation), I have a few specific concerns with Evan’s plan. To wit:

  • Cost, mentioned above. Who pays? How much?
  • Is this more of a priority than improving Baltimore’s public transit system?
  • Do existing Columbia villages and other neighborhoods listed as potential stops have adequate populations of potential riders to make the system work?
  • Related, are these areas dense enough to make riding public transit a viable alternative (that is, would people live close enough to the stops to justify walking)? If not, and significant parking is needed, is such parking appropriate for some the neighborhoods?
  • Can we really expect, even in the 30-year time frame, county residents to use public transportation for local trips? One of Evan’s commenters said, in so many words, “No.”
  • Should we rely, as another of Evan’s commenters said, on 19th century technology for our future transportation needs? (Brining this up does not necessarily put me in the PRT camp, by the way).

Since I’m on the topic of PRT, I’ll respond to the anonymous commenter who has long extolled the virtues of Personal Rapid Transit (and who I’m tempted to start calling PRTer or something like that just to make comment section discussions easier).

Although it sounds good on paper (or, rather, in HTML), I have questions about how it would work in practice. First, do you think people would really be willing to give up their cars for Maglev pods?

How feasible – in terms of maintenance, security, cost, and citizen buy-in -- is it to have a network of these towers and tracks almost as extensive as our existing road system?

Has a functional model of this system been built? I’d be very hesitant to be the guinea pig for an unproven transit technology.

It seems to me that even though convenience (or lack thereof) is a significant reason for people not using public transit, there's also a more psychological one; namely, the lack of control. Driving gives us a lot of control (or, rather, the perception of control) over our surroundings and our fate, while sitting in a train, plane or pod places our lives under the control of some unseen operator or some faceless computer, which for some people, is enough to dissuade them from riding.

Having no control is part of what makes flying uncomfortable for me. The seats, naturally, are the other part.

14 comments:

A Transportation Enthusiast said...

The anonymous PRT poster appears to be talking about Skytran/Unimodal, which is just one of many PRT designs. Skytran is a very innovative and forward thinking design, incorporating a novel passive maglev called Inductrack. The problem with Skytran is that it's an immature proposal, more of a concept than a design really, and so implementing a system like Skytran would be a significant risk. The cost figures, in particular, seem to be quite speculative.

Other PRT efforts are further along in development than Skytran, including British ULTra, Korean Vectus, and, in the US, MicroRail and Taxi 2000. No commercial version of any of these has been built, though several have built prototypes. ULTra is the furthest along, with plans to deliver a commercial system to Heathrow airport in the next two years.

It should also be noted that Skytran is the only well-known PRT design that uses maglev; all other notable designs use wheels on tracks (or, in the case of ULTra, roadway). Many, however, do use linear induction for propulsion. Also, most designs feature top speeds of no more than 40-50mph, although because PRT is nonstop, they are still significantly faster than the equivalent train or bus trip.

More realistic cost figures for PRT systems seem to be in the $10-20M per mile range, though cost estimates vary widely.

There's a nice article on PRT at Wikipedia if you want to research it further.

Hayduke said...

Wow, thanks for all the links. I meant to include the SkyTran.net link but forgot before hitting publish. I've updated to include it.

You are obviously, as your name indicates, a transportation enthusiast. What do you think about the viability of PRT?

A Transportation Enthusiast said...

I came across PRT about 6-8 months ago, and I was initially swayed to the negative by the criticism. There is a lot of very harsh criticism of PRT, but upon investigation, I found that most of the criticism is political in nature, and technically unfounded.

PRT is certainly viable. I've searched high and low for the "killer technical argument" that debunks the technology, but I can't find it. The concept is sound and as long as the engineering is good, there's no reason why a safe and effective PRT system cannot be built.

The main problem PRT faces is public acceptance. It's such a radically different way of doing public transportation that many people (even experts) discount it as unworkable. Opponents take advantage of this ignorance, using scare tactics to drive down public support. For example, some activists claim that PRT is unsafe or susceptible to terrorism, even though there is an abundance of evidence to counter these claims. But because public transit is so political, just a hint of political controversy causes many politicians to support politically "safer" options like light rail.

There are some hurdles. For example, studies have shown that people might be concerned about the aethetics of an elevated guideway in a city center, even if it's a low profile guideway. These are legitimate concerns, although I believe that many would be willing to accept a narrow elevated guideway if it meant lower traffic and fewer parking garages in the city center.

For me, I'd love for a system to get built, just to see if it could be as good as promised. PRT might just be convenient enough to actually draw people away from their cars in great numbers, something other transit options have consistently failed to do. There's really no public transit option that comes close to the level service that PRT promises to provide - safe, non-stop service with little or no waiting, available 24x7. Cabs come close to this level of service, but are much more expensive for passengers (making them impractical for most commuters), and much less safe.

If PRT could deliver on its promises, it could be as revolutionary as trains in the 19th century, or the automobile in the 20th century. It could also be a collosal failure if it's not done right, but that's a risk with any new technology. PRT would be classified as a high-risk-high-potential-reward effort.

Anonymous said...

I agree the perception of control is important, too. However, consider the analogy of an elevator. You get in a pod (albeit one that travels soley vertically, unless you're visting Wonka's factory), the doors close, and you push a button. In many cases, you can't even see outside the pod. And away you go. Up 1000 feet. You could instead maintain perception of control and take the stairs. After a few elevator rides, a lot of people opt to forego the stairs.

Equate the exertion of using the stairs to all the disadvantages of using cars vs. PRT (time, money, environment, traffic frustration, etc.) and a lot of folks would opt for stepping into the pod and pushing the button.

Also, aren't about half our national road fatalities due to DUI? In these situations, a lot less driver control and more PRT control could save lives. Imagine when overindulged fans are leaving a sporting event/concert/festival and they have the option of PRT to take them within walking distance of their homes. Having taken public transit to/from various events, it's actually quick, pleasant, and convenient.

And, as I've mentioned before, our aging population will more and more often decide it's a good convenience to not have to exercise control of their transportation. Home, James.

I don't consider that Skytran hasn't been built yet to be a problem. If we're talking about a master plan for town center Columbia that will meet transportation 30 years from now, it's a no-brainer that such a plan needs to include mass transit. Why not choose the most innovative PRT design and pursue it? Thus, it's unfair to claim it's a significant risk vs. either opting for other transporation solutions which basically surrender all the benefits that advanced PRT offers or vs. omitting including a viable mass transit infrastructure from the 30 year plan altogether.

Maglev technology (see Wiki), similar to what Skytran would use, has been used in some public transit systems since the '80's and is what the 300 mph top speed Baltimore-BWI-DC maglev train will use. Ride it four years from now and see. Interesting to note, maglev train technology was first patented in Germany in 1941. Even before that, in the 1910's, America's rocket guru, Robert Goddard, designed a vactrain (maglev train that travels through an evacuated tube) that would travel 1000 mph. And even more radical current (yet prohibitively expensive) vactrain designs propose systems traveling 4000-5000 mph (Mach 5-6). So a 100 mph aerodynamic PRT vehicle being used a decade or so from now doesn't seem that far out there.

What makes designs like Sktran/Unimodal feasible now is the availablility of strong lightweight materials, computer-aided highly aerodynamic designs, fast/reliable computer control systems, etc. Hardly a "risk".

A few other unfortunate things to consider while discussing risks - light rail colliding with BWI *twice*, light rail accidents colliding with cars (usually due to cars pulling in front of them) and pedestrians, and multi-passenger mass transit vehicles all too often chosen by idiots to do bad things in this world of late.

A Transportation Enthusiast said...

I consider Skytran more of a risk only because it seems to be immature compared to other proposals. All the others I mentioned use more conventional technology, and each has built some type of prototype. Not so with Skytran, which is both more advanced and lacks even a prototype.

I do like several aspects of Skytran, and it may eventually become more mature and leapfrog existing technologies. But for the here-and-now, I think one of the other proposals has a better chance of succeeding.

Avidor said...

Hey, A.T.E. You forgot to mention that Skytran is cheaper to build than LRT because of its unique guideway-extruding robot.

Anonymous said...

A nice video showing a working maglev levitation/propulsion system.

And, for considering if there would be a citizen "buy-in" accepting a network of elevated narrow PRT guideways, a good animation of a PRT system proprosed for Microsoft's campus. Notice how small the PRT footprint is compared to adjacent roads. Bear in mind also, one PRT lane can handle the traffic of three road lanes.

Anonymous said...

Skytran may be closer than you think.

Anonymous said...

As to the lack of control factor:

While I do enjoy my commute some days, windows down, radio up, zipping around the state's highways, I would happily give that up for convienient mass transit.

I do not commute near DC, but when I do visit DC, their government has convinced me that I do not want to drive there. Traffic, one way streets, road closures, traffic signals hidden to the side of the roadway, redlight camreas, speed cameras, parking issues-no thank you-I love Metro. Maybe I have to wait a few minutes for a train, walk a little bit, transfer, and give up my radio and my control but that pales to the above.

There are ways to convince people that they really rather use your mass transit system.

Anonymous said...

PRT? It is the like the blimp,
interesting to talk about, not used in transportation. Most of the systems pushed are stock scams and gov. handouts to insiders.

There are large scale failures, like the Denver International Airport Luggage Handling system that was thrown away after years of unsuccess.

Anonymous said...

I imagine you'd be the one standing at Kitty Hawk in 1903 saying "Flying machines? Interesting to talk about, but not used in transportation."

PRT like the blimp? That's a pretty poor analogy for this discussion goes since blimps are slower than current air transportation whereas PRT will be faster than current ground transportation. Perhaps a more valid analogy - blimps are to planes what cars are to PRT.

If you do want to cite luggage handling systems as an example of if large-scale PRT systems can work, while Denver's system failed, a dozen successfully implemented automated airport luggage systems have been deployed since then (all in Europe) and have enjoyed years of ongoing success. A few other examples of such large discrete automated transportation systems that work fine day in and day out - Fedex's, UPS's, and WalMart's.

I certainly hope the government does fund transportation research appropriately, just as it should for medicine, the environment, and other systems that affect and benefit us all. Yet, your reference to scams and handouts makes me wonder. Why are you tossing out blimps, one luggage system, and broad-brushed smear of PRT in general instead of directly addressing PRT's technology and many advantages instead, especially considering this is a discussion of a forward-thinking transportation plan (good enough for the next 30 years) for Columbia's town center in particular and the region in general.

Anonymous said...

Kitty Hawk 1903, forty years later the
plane was common all over the globe.

Forty years after PRT, nothing but hot
air and a trail of scams and failure.
PRT is dead like the blimp.

Anonymous said...

The baggage handlers of Europe all are conveyer systems, not like the autonomous pod on demand roaring
around on a track failed PRT system of Denver Airport. Again, airport PRT is dead, but conveyer belts
are in wide use. In fact conveyer belts are used as "fast sidewalks" and escalators in airports to move people, nary a pod is used anywhere on earth not even for a suitcase (Denver Airport baggage PRT shut down)

Anonymous said...

Anonymous 10:13&10:21, you must have had a rough 8 minutes there.

You said PRT is 40 years old and there's nothing but hot air/scams/failure. Well, here's some hot air that's been running continuously since 1979.

You also said the successful European airport baggage systems are all conveyor systems. Try rereading the MHM Online link from above - "These successful projects utilized basic material handling technologies that range from nearly identical (passive, dumb carts) to radically different (active, intelligent carts) than that implemented at DIA". Active, intelligent carts sound neither much like a conveyor nor very dead as you said, now do they?

And, by the way, maybe you should've started the clock on flying machines not at 1903, but back in 1783 with Montgolfier. At least then your reference to hot air would have been more applicable.