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[P]
Personal Rapid Transit Test

By SEWilco in News
Tue Nov 05, 2002 at 08:35:22 AM EST
Tags: Technology (all tags)
Technology

A Star Tribune article reports that a Taxi 2000 test track will demo one of their Personal Rapid Transit small self-guided vehicles.


Personal Rapid Transit uses small vehicles which travel directly to the single destination requested by the rider. A rider specifies a destination at the station, and if a vehicle is not at the station one is summoned. They're more like a horizontal elevator than a bus or rail transit, which have to make many stops along a route. A full PRT system would have many loops or a grid of tracks, with each vehicle following its own path to its destination.

Obviously, on a test loop or line the vehicle will have no trouble going directly to the destination station. Although it is the independent routing which makes PRT different from mass transit, the routing task is now easily performed by computers. PRT could have been built long ago, by using old technology such as used by cable cars. But the mechanical clockwork to calculate routing would have been too fragile.

Also ATRA is making a non-functional PRT model to show what PRT looks like in a real world city. There also is a similar ULTra system being developed in Cardiff, Wales.

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Poll
Do you need a car in your city?
o Yes 32%
o Only for work and shopping 6%
o Only for shopping 6%
o Only when dealing with large objects 19%
o No, a taxi works fine when mass transit doesn't 10%
o No, never need one 17%
o No, my jet pack gets me wherever I need to go 6%

Votes: 172
Results | Other Polls

Related Links
o Star Tribune article
o Taxi 2000
o Personal Rapid Transit
o ATRA
o PRT model
o ULTra
o Cardiff, Wales
o Also by SEWilco


Display: Sort:
Personal Rapid Transit Test | 43 comments (38 topical, 5 editorial, 0 hidden)
How is this different? (4.00 / 2) (#3)
by dani14 on Mon Nov 04, 2002 at 06:36:01 PM EST

How are these PRT's different than subways, monorails, or moving sidewalks? From the one link about the PRT Model, this looks like an amusement park ride, with a fixed track and set spacing between cars.

I don't see how this would change mass-transit, as you'd still have limit selection of destinations. I guess the smaller cars would mean more continuous flow, rather than discrete, but is the goal to attract more passengers through this feature?

--


"The samaritans parable obviously missed the bit where jizzbug ... kicked the crap out of the guy "just to see if he could do it, you know, to test if the law was perfect and all"." -- Craevenwulfe
It's closer to on-demand transit (none / 0) (#5)
by Arthur Treacher on Mon Nov 04, 2002 at 06:56:25 PM EST

The waiting time for a vehicle would be dramatically reduced.  The system would allow for better resource allocation - vehicles go when and where people want them to go, rather than having a set schedule.

I can see this working quite well.  The hard part will be convincing a community to build the first one.

"Henry Ford is more or less history" - Bunk
[ Parent ]

Science Fiction Movies (4.00 / 1) (#17)
by Al Macintyre on Tue Nov 05, 2002 at 02:26:49 AM EST

It might help to compare where we are, or appear to be heading, with how similar stuff shows up in the movies.  I can't remember the movie now where our hero went to Total Recall to be a Secret Agent on a trip to Mars, and he ran into some trouble with Johnny Cab (robot driving taxi to where you want to go).

Today there are people struggling to make a living driving a taxi, 18 wheeler, etc.  Would this technology put them out of work?

Today there are vending machines that eat our coins, and we bash them in to get our change.  There used to be pay phones all over, but now mainly just at highway rest stops ... I suspect that people stealing coins from them are part of the reason why they are history.

People who target Taxi drivers for muggers are a fact of life, but not bad enough for Taxis to go out of business, but people who have fights with vending machines are another matter.  How will these machines protect themselves from dissatisfied customers, without violating privacy of the ordinary peaceable customers?

Will I be able to use a cellular phone to summon one of them to pick me up WHEREVER I HAPPEN TO BE?  Right now when I call an ordinary taxi, they say they will be there in 20 minutes, which could be anywhere from 10 minutes to 20 hours in reality.

- Al's weblog: http://radio.weblogs.com/0107846/ donate your unused PC resources (only when you not using them) to cure cancer http://members.ud.com/about/
[ Parent ]

Movie ref (none / 0) (#21)
by Ricochet Rita on Tue Nov 05, 2002 at 08:24:59 AM EST

"Total Recall" (1990) with Arnold Schwarzenegger
IMDb.com

R

R

FABRICATUS DIEM, PVNC!
[ Parent ]

Progress (none / 0) (#25)
by vrai on Tue Nov 05, 2002 at 09:59:55 AM EST

Today there are people struggling to make a living driving a taxi, 18 wheeler, etc. Would this technology put them out of work?
Lots of people lose their jobs everyday because the services they provide are either not needed anymore, or are cheaper/better to do by machine. Potential job losses are not a reason to avoid doing something. Either your skills allow you to adapt to market conditions or you end up on the street, it's been this way since the industrial revolution.
Today there are vending machines that eat our coins, and we bash them in to get our change. There used to be pay phones all over, but now mainly just at highway rest stops ... I suspect that people stealing coins from them are part of the reason why they are history
Why use coins? What's wrong with using your credit/debit card to make the transaction? For people that don't have plastic you could provide pre-paid/rechargable travelcards.
How will these machines protect themselves from dissatisfied customers, without violating privacy of the ordinary peaceable customers?
They could photograph people trying to damage them and call the police for help. They could even lock the doors and drive to the nearest police station. People vandalise trains, buses, and parked cars (even moving cars if you drive through the wrong areas); yet society manages to continue unabated.
Will I be able to use a cellular phone to summon one of them to pick me up WHEREVER I HAPPEN TO BE?
You're comparing these to taxis whereas the proposed system is more similar to a personal bus service. The difference is that these are more frequent, you don't have to share them with others (something that scares most Americans), and they are always heading along the right route. Some people will always take taxis, and that's cool. However others can't afford to get a cab everytime they go out. This provides a nice middle ground: more convienent than a bus, less expensive than a cab.

[ Parent ]
Pay phones (none / 0) (#39)
by Verminator on Tue Nov 05, 2002 at 09:20:15 PM EST

There used to be pay phones all over, but now mainly just at highway rest stops ... I suspect that people stealing coins from them are part of the reason why they are history.

I'd suspect that the rise of cell phones is the reason we don't see many payphones anymore. That and the fact that they raised the charge for a call above a quarter. A quarter is convenient (not as convenient as a dime of course), 35 cents, or whatever the going rate is these days, is a pain in the ass.

Fear leads to anger, anger leads to misery, misery links to Satanosphere.
[ Parent ]

Anyone? (3.00 / 4) (#4)
by CaptainSuperBoy on Mon Nov 04, 2002 at 06:51:38 PM EST

Gratuitous link to The Simpsons monorail song? Anyone? Anyone?

--
jimmysquid.com - I take pictures.
If you insist (3.00 / 2) (#6)
by rusty on Mon Nov 04, 2002 at 07:27:40 PM EST

Well there's nothing on earth like a genuine electrified bonafide six car monorail.

What'd I say?

Monorail!

What's it called?

Monorail!

That's right, Monorail!

____
Not the real rusty
[ Parent ]

monorail in someone's backyard, literally... (5.00 / 4) (#10)
by kpaul on Mon Nov 04, 2002 at 07:58:47 PM EST

Niles Monorail page


2014 Halloween Costumes
[ Parent ]

That is (3.25 / 4) (#12)
by rusty on Mon Nov 04, 2002 at 10:34:55 PM EST

That is simultaneously one of the dorkiest and one of the coolest things I've ever seen. Thanks for the link. :-)

____
Not the real rusty
[ Parent ]
Listen (2.00 / 6) (#7)
by CaptainSuperBoy on Mon Nov 04, 2002 at 07:33:04 PM EST

Now listen SEWilco. I'm in a bad fucking mood. I'm actually on steroids because of a pneumonia/asthma flare-up, I'm in a rage right now as I type this. You rated a comment in your own story, while it's in edit mode, and I will take this story and make it go down in flames. Everyone is allowed one K5 pet peeve. That's mine.

--
jimmysquid.com - I take pictures.
[ Parent ]
I have a "complain about moderation" pet (5.00 / 1) (#18)
by Big Sexxy Joe on Tue Nov 05, 2002 at 02:42:40 AM EST

Although your comment was funny so you get a two instead one.

I'm like Jesus, only better.
Democracy Now! - your daily, uncensored, corporate-free grassroots news hour
[ Parent ]
Already in my own backward state... (4.75 / 4) (#8)
by dannyboy on Mon Nov 04, 2002 at 07:33:28 PM EST

Behold, the WVU PRT.

May I suggest... (2.50 / 2) (#14)
by phony on Tue Nov 05, 2002 at 12:02:37 AM EST

a new poll option?

"Do you need a car in your city?"
Only if you don't mind being mugged.

What I think would be feasible, cheap and useful (3.60 / 5) (#15)
by pattern against user on Tue Nov 05, 2002 at 12:44:29 AM EST

Is make cars autopiloting. Stick a camera onto them, and vision processing computer, input a destination and let it drive you there with an onboard processor. I spend a lot of my time driving, if I could do something else in the car I could be a lot more productive...not that I don't talk on my mobile.

How far has the technology come along? Last I heard they had reached 5 km/h on an empty road. Surely 2ghz is enough processing power to drive a car with..?

Of course the technophobes will say they won't trust computers. Well I think a well designed, programmed high-perfomance computer with multiple processors would probably be a lot safer than a human. 40k people die every year because of bad driving, I mean it can't be much worse than that?

And just imagine if all the cars were networked and they could query each other via wireless. That way traffic could organise itself as a whole, rather than each trying to make the best decision based on incomplete information.

Smart Cars Theory vs. Threat (3.40 / 5) (#16)
by Al Macintyre on Tue Nov 05, 2002 at 02:16:18 AM EST

In theory, microprocessors on each car, connected to GPS, and local cameras, mean that you avoid the pile up around the corner, because the car sees the blockage before the driver does, and slams on the brakes in time.

In practice, competition drives this to the lowest bidder, and we get a solution that a hacker / cracker could drive a a lot of abuse through.

Use the cameras to find a female target who is a "looker."  Hack into her car to cause it to retransmit her to where you plan to ambush her.

Run the license plate numbers through a data base to find who is the most wealthy of the local easy pickings targets.  Gum up the works.  Car stops, you offer to help, you really a car jacker and you also targeting the occupants.
- Al's weblog: http://radio.weblogs.com/0107846/ donate your unused PC resources (only when you not using them) to cure cancer http://members.ud.com/about/
[ Parent ]

Actually (4.50 / 2) (#26)
by Kal on Tue Nov 05, 2002 at 10:17:01 AM EST

Carnegie Mellon had a car that drove itself across country at about 70 mph. Only problem was that it followed the right hand white line and liked to follow it onto the off ramps. Once they fixed that problem it drove across country 95% on its own.

[ Parent ]
Auto Autopilots (4.00 / 1) (#27)
by SEWilco on Tue Nov 05, 2002 at 10:36:01 AM EST

Several projects have had automatic cars driving themselves faster than 50 MPH, not only 5. Some designs use magnets in the roadway, some use optical methods.

[ Parent ]
Might work, but we won't let it (5.00 / 2) (#33)
by kphrak on Tue Nov 05, 2002 at 12:15:02 PM EST

I think we could probably achieve what you're talking about, but although the technology is probably there, the social mindset is not. People who see their desktop crash every day at work are unlikely to react favorably to a computer controlling their driving.

In addition, the very fact that the computer would be a better driver might work against it. Doesn't run red lights (or even yellow, if it plays by the rules)? Doesn't go over the speed limit? Doesn't cut across five highway lanes to get to that exit (a common dodge in my home state)? Like the teenager who complains that Mom "always drives slow" because she brakes at yellow, people are going to be disabling this because they don't want to follow the rules.

In addition, the car is used all too often as a penis substitute. Fast, hard driving is glorified in movies (Transporter, to name a current one which rocked). Auto ads emphasize the independent, strong man (or woman) who buys their automobile. And everyone buys that image.

It's a nice idea, but it's hellaciously expensive, and everyone would want to be the exception to the rule. Maybe someday.


Describe yourself in your sig!
American computer programmer, living in Portland, OR.


[ Parent ]
They would BE safer... (5.00 / 1) (#35)
by Control Group on Tue Nov 05, 2002 at 04:22:45 PM EST

...but they wouldn't be PERCEIVED as safer. No one is going to be willing to accept that the accident the computer got into was less likely than the accident he is certain he would have avoided (though there is about a 99% chance he's wrong). Even if the number of deaths from automobile accidents decreased by 75%, people would still think it dangerous, because they had no chance to avoid it.

This is the same reason people who drive to and from work every day can be afraid of flying - if something goes wrong, there's nothing they can do to change it.

Of course, you could put in a manual override...but then it's virtually certain people would us it at the worst times, and you've now lost the advantage you were trying to gain. After all, everyone considers himself an above-average driver...

***
"Oh, nothing. It just looks like a simple Kung-Fu Swedish Rastafarian Helldemon."
[ Parent ]

There's one at Amsterdam Airport (4.80 / 5) (#19)
by Ranieri on Tue Nov 05, 2002 at 06:45:06 AM EST

Amsterdam Airport (known as Schiphol to the locals), has a similar system called ParcShuttle at their long term parking lot. Passengers drop off their car, then walk to a pick-up point and push a big lit green button. Within a few secons an unmanned vehicle pulls up, the doors open and the passenger is taken to the bus terminal.
Conversly when picking up the car you can summon a vehicle, specify your destination (in parking coordinates, e.g. B7) and the vehicle will bring you to the nearest pick-up (== drop-off) point.

As far as i have been able to determine, the thing navigates through permanent magnets embedded in its tarmac ``track''. It uses separate lanes from normal traffic and slows to a crawl when nearing pedestrian crossings. If there's an unexpected object in its path (for example a car that is standing still on an intersection) it will detect it (presumably through optical means) and it will attempt to bully its way through by blowing its horn and flashing the headlights.

While the system might be a bit immature for city-wide deployment, it certainly does the job of getting the people to/from their car rather effectively. The vehicles are also extremely cute :)
--
Taste cold steel, feeble cannon restraint rope!

Follow-up (none / 0) (#20)
by Ranieri on Tue Nov 05, 2002 at 06:53:23 AM EST

There amazingly little information on this system on the, and (apparently) no pictures whatsoever.

This article states:

Rubber-tired people movers are another area of research and deployment. One such example is the unmanned ParcShuttle at Amsterdam's Schiphol Airport. ParcShuttle implements a "horizontal elevator" concept, using free-ranging-on-grid (FROG) technology to pick up people at remote parking sites and take them to their desired terminals.

--
Taste cold steel, feeble cannon restraint rope!
[ Parent ]
Guidance (none / 0) (#28)
by SEWilco on Tue Nov 05, 2002 at 10:49:30 AM EST

I'm aware of several technologies used to guide vehicles over a flat surface:
  • Buried wires which emit radio signals
  • Buried magnets
  • Laser scanning of reflectors in ceiling
  • GPS/Differential GPS (mostly on water)
  • Magnetic or Ultraviolet fluorescent ink (in carpeted office areas)


[ Parent ]
What's the benefit? (4.00 / 3) (#22)
by Rogerborg on Tue Nov 05, 2002 at 08:37:27 AM EST

Really, I don't get it.

There's no reason that these vehicles should be more efficient in use than personal vehicles.  Given the replacement and maintenance schedules that I see on public transport today, I'd guess that they're more likely to fall behind the standards of efficiency of the personal vehicles owned by the people that might consider switching (i.e. Sam Suziki, not Sarah SUV).

So the benefit is a reduction in the "capital" costs of building more vehicles?  Uh, wait, how many people are going to give up their personal vehicle entirely in favour of one of these?  I might take the bus to work every weekday (if there was a bus to take...), but I damn well need a car for the evenings and weekends.

Also, doesn't rush hour account for a major proportion of the traffic on the roads?  We'll still need a shedload of these things to cover that.  Crikey, and what happens when one of them breaks down (or the local kids put a traffic cone in front of it when it doesn't have a passenger in it)?  Can it pull itself off the road?  Can the other vehicles route round it?  Best case, it's no better than the current situation.

The only major effect that I can see of these things is to put some taxi drivers out of jobs, and provide a nice revenue stream to the manufacturers and maintainers of these devices, as they get regularly wrecked and vandalised.

So, can anyone tell me what I'm missing?

"Exterminate all rational thought." - W.S. Burroughs

Details (4.33 / 3) (#24)
by SEWilco on Tue Nov 05, 2002 at 09:56:55 AM EST

Well, if you NEED a car for evenings and weekends then you might have one. PRT reduces the number of people who need a car. PRT lets you go shopping for bulky items more easily than with a bus. And the vehicles come when you request one, so you don't have to deal with reduced evening bus schedules.

During rush hour vehicles will be reused. Some will have to run back empty, just as buses in some directions are almost empty during rush hour. But these vehicles are lighter than buses so won't need as much power. Rush hour demands have been simulated...PRT has been studied for decades.

The kids will have to have good aim with that traffic cone, 16 feet up. But other vehicles will be told that route is blocked and will take another path through the grid. If the vehicle is malfunctioning but can still move, it can get to a maintenance location on its own. If it can't move, a tractor unit might have to push it (I don't know if ordinary vehicles could be told to push another).

Kids will have some difficulty doing vandalism. They'll have to find unused vehicles where they can be reached. If they buy a ride and mess it up, the next customer will press the "VEHICLE BROKEN" button -- and the maintenance staff will see the mess then look at the video and ticket purchase info for the previous riders. The kids will have more difficulty staying anonymous than in a subway car which carries other people. (all this is mentioned in several PRT descriptions)

The main advantages are that PRT goes to your destination quickly (probably faster than cars in a city), and when you need it rather than on a bus schedule. Advantages to the city include that one narrow PRT line can carry as many people as several lanes of street. There aren't enough taxis in any city, but PRT is a 20th century replacement for buses/trolleys. Also for some delivery routes when in "cargo" or "private shuttle" mode.

[ Parent ]

Missing something (4.00 / 2) (#29)
by nazhuret on Tue Nov 05, 2002 at 11:33:07 AM EST

I don't know the details of this system (yet) but another point to consider.

Fully automatic transportation will virtually eliminate traffic accidents.  When was the last time you were stuck in traffic because someone had a minor fender bender (and everyone slowed down to look)?  I'm guessing it wasn't that long ago -- it happens to me frequently.  Not to mention the times I have to wait for major accidents...

[ Parent ]

I own a Personal Rapid Transit vehicle. (4.20 / 5) (#23)
by jvance on Tue Nov 05, 2002 at 09:36:00 AM EST

It's called a "bicycle."

---

This is taking too much of my time. I've gone away. You can reach me at john_a_vance atsign hotmail dot com if you wish.

I got one too (none / 0) (#30)
by Schnapp23 on Tue Nov 05, 2002 at 11:43:46 AM EST

Its called a car, the routes are already in place and the routing system is adaptive and robust. Its really amazing, everyone should try it.

[ Parent ]
You must... (none / 0) (#40)
by TheEldestOyster on Wed Nov 06, 2002 at 03:53:28 AM EST

...not live in Southern California.
--
TheEldestOyster (rizen/bancus) * PGP Signed/Encrypted mail preferred
[ Parent ]
Motorized scooter... (none / 0) (#34)
by msphil on Tue Nov 05, 2002 at 02:59:08 PM EST

Saw a guy in his mid to late 50's, very out of shape, on a motorozied scooter and looking very goofy. No way he could've done a bicycle...

Funny thing was, he pretty much kept pace with us (I carpool these days) as we drove home -- traffic evened out the speed difference.

It was very, very cool to see (although we chuckled when we first caught sight of him).

[ Parent ]

Note to scooter drivers: (5.00 / 1) (#38)
by it certainly is on Tue Nov 05, 2002 at 09:09:25 PM EST

please get out of my way. The fact is: your piddling 125cc motor is no match for my thick, manly legs.

Anything with motors just makes you fat.

kur0shin.org -- it certainly is

Godwin's law [...] is impossible to violate except with an infinitely long thread that doesn't mention nazis.
[ Parent ]

Not again (5.00 / 2) (#31)
by wumpus on Tue Nov 05, 2002 at 11:51:56 AM EST

The size of the cars and spacing indicate that this is unlikely to have the throughput of a single lane of (car) roads. The basic problem of personal (public) transportation is that people have to be transported from arbitrary points to arbitrary points. Cars (and to a lesser degree, bicycles) solve this. In some places, subway systems are large enough to be barely usefull. The most obvious issue is price per (PRT) car. This must be significantly lower than a (personally owned) car. Unless this PRT can make several round trips during rushhour, there must be roughly 1 per comuter (how this is better is beyond me). Every other form of public transportation has to meet this criteria (for whatever terms of cost is used), but for the PRT concept it is hopeless. While I would be interested in a system of transportation that could somehow overcome both the problems of quickly delievery passengers from arbitrary locations to arbitrary locations and achieve low per-commuter cost, I don't know how this could be retrofitted into densly populated areas (the only place they hope to work). My guess is we will just have to get used to having mandated controls, automation (pun not intended), and testing of self-guided cars. Libertarians will just have to stay out of cities. Wumpus

Once again with formating... (2.00 / 2) (#32)
by wumpus on Tue Nov 05, 2002 at 11:54:41 AM EST

The size of the cars and spacing indicate that this is unlikely to have the throughput of a single lane of (car) roads.

The basic problem of personal (public) transportation is that people have to be transported from arbitrary points to arbitrary points. Cars (and to a lesser degree, bicycles) solve this. In some places, subway systems are large enough to be barely usefull.

The most obvious issue is price per (PRT) car. This must be significantly lower than a (personally owned) car. Unless this PRT can make several round trips during rushhour, there must be roughly 1 per comuter (how this is better is beyond me). Every other form of public transportation has to meet this criteria (for whatever terms of cost is used), but for the PRT concept it is hopeless.

While I would be interested in a system of transportation that could somehow overcome both the problems of quickly delievery passengers from arbitrary locations to arbitrary locations and achieve low per-commuter cost, I don't know how this could be retrofitted into densly populated areas (the only place they hope to work).

My guess is we will just have to get used to having mandated controls, automation (pun not intended), and testing of self-guided cars. Libertarians will just have to stay out of cities.

Wumpus

PS. Is there some way to edit the above and include the paragraph breaks?

[ Parent ]

Answers (none / 0) (#36)
by SEWilco on Tue Nov 05, 2002 at 04:23:01 PM EST

  • Throughput: Headways of as little as half a second mean the spacing is close. The Taxi2000 FAQ 2 says "One PRT line can serve more than six times this capacity, more passengers per hour than come into downtown Boston during the morning rush period via a three-lane expressway."
  • Cost of PRT vs car: "Intuitively many engineers have believed that the cost per unit of capacity of small vehicles must be greater than the cost per unit of capacity of large ones. The data showed otherwise. Notwithstanding many more wheels, motors, control systems, etc., we found that the cost per unit of capacity of transit vehicles is independent of vehicle capacity, and several times the cost per unit of capacity of a common automobile. The major reason is the difference in production quantity, but also relates to the size of facilities and the time required to handle a few large objects rather than many small ones."
  • Arbitrary destinations: That's a feature of PRT. You can get between any two points which are within "walking distance" (well, a bike might fit in a PRT vehicle) of any two PRT stations. Your comparison to subways is irrelevant, as that is a different mode of transport.
  • Fit in existing cities: Look at the descriptions of the track and vehicle. About one-half or one-third the width of a road lane, but overhead installation allows placing above existing road or sidewalk. Bends fit between existing buildings (I think Taxi2000 mentions 40 feet between buildings).


[ Parent ]
The benefit. (5.00 / 2) (#37)
by hollo on Tue Nov 05, 2002 at 06:16:22 PM EST

The arbitrary location to arbitrary location is the main benefit of these systems. You need to think of them as automated taxis running on rails rather than conventional transport.

The idea is to have a network of the monorails across the city with intersections with stations as sidings off the main track. You enter the station, buy a ticket to your destination, and put it in the cab that is waiting. It waits for a gap in the traffic, pulls out, and travels to the destination. Since the stations are off the main track no cab should ever need to stop on the track.

The touted benefits of this are:

  • Low energy consumption - no acceleration / deacceleration except at the beginning and end of your journey, combined with a low resistance track and regenerative breaking.
  • Fast because there are no inefficient road junctions where traffic in one direction must wait for traffic in the other.
  • More private than existing public transport.

    Given a way to accurately know the position of every car on the track I think this would be doable. Interleaving cars in places where two tracks merge could be tricky, but either you run cars double the distance apart in the sections leading up to the join, or use a more complicated dynamic algorithm - the whole idea being that cars shouldn't need to slow or stop at these points. I think I remember the taxi2000 people had a (Windows) binary that did a graphical simulation of the network in an American city, so they certainly had the routing problem sorted out in software.

    What I am not so confident in though is an accurate way of keeping track of a cars position on the track. GPS is inaccurate, and trackside sensors a bit unreliable.



    [ Parent ]
  • hmmm... (none / 0) (#41)
    by Danse on Wed Nov 06, 2002 at 02:22:58 PM EST

    It would be neat if they would let people help test the routing software for such a system. Create a net app that simulates a PRT system for a good-sized city and allow people to call cars to a location and then give them a destination. See if having thousands of people doing this can create any problems.






    An honest debate between Bush and Kerry
    [ Parent ]
    SimCity showed us all.. (none / 0) (#42)
    by McMasters on Wed Nov 06, 2002 at 03:06:30 PM EST

    ..exactly how well a city runs on 100% mass/ automated transit. Have an emergency lane for emergency vehicles, keep it all running day and night, and post a cop or two to make sure the sararimen aren't feeling up the schoolgirls again. Millions of dollars saved, lives saved, trees saved, etc. etc. I already take the bus. With this, I'd be travelling in style.

    They already have these in use. In YOUR city! (none / 0) (#43)
    by gromm on Thu Nov 07, 2002 at 03:21:15 AM EST

    They do an excellent job of routing, they come on a moment's notice when they're called, they react to unexpected circumstances with intelligence, and each one is reused many times a day by different people, increasing efficiency over the ownership of any single occupant vehicle.

    They're called "taxicabs."
    --
    Deus ex frigerifero

    Personal Rapid Transit Test | 43 comments (38 topical, 5 editorial, 0 hidden)
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