> I would be more interested in how the system handles busy junctions since the tracks must join and intersect.
That's a great question and one of the best qualities of the system (I've been following its development for a few years now as an interested observer). The tracks are all one way so there is only a merge-type intersection to worry about. Unlike a train, the track doesn't move to divert the cars. Instead, each car has a type of "arm" with a wheel on each and that keeps it holding to the left or to the right. A good image of the switch is here:
http://kinetic.seattle.wa.us/~prt-q.html#gsmall
Since the switch mechanism is in the car, there is no overhead involved in switching the track.
> Also its a one way system so trips could be quite convoluted and time consuming.
Since it is a system of one way loops, there are some indirect trips, but the advantages are that it is a non stop trip. Here is another good example of how a car trip would compare with a PRT trip:
From http://kinetic.seattle.wa.us/~prt-q.html#chaos
"No rear-end or merging collisions, because the vehicles are not operating independently. All are communicating with a central computer system that keeps tabs on traffic throughout the network. In principal it works like this: Cars continuously report their positions (every 40 milliseconds in Taxi 2000), and the central computer system tracks their location; the two sets of data are continuously compared. If a vehicle does something it's not supposed to do (such as follow too close, stop unexpectedly, a mechanical breakdown, or even if the vehicle's reporting signal is interrupted), the central system will send commands to fix or avoid problems-- "deccelerate for 3 seconds", for example. This system is always in operation, ensuring safe distances between vehicles whether on straightaways or at junctions."
With regard to getting out of a stopped car,
"There are over 70 elevated automated transit systems operating in the world today that prove that a vehicle stopping when not intended is a very rare event. If a vehicle does stop between stations, Central Control will talk with the passengers through an intercom system and guide the rescue operation. The vehicle behind will soft engage and push the disabled vehicle to the nearest station. In the very unlikely event that the vehicle can't be moved, a rescue team will come with a ladder and help the passengers out of the vehicle."
yeah.. you've got the right idea. This is from teh skywebexpress website:
Station Capacity
(Stations can be sized from one to about 15 berths)
450 Vehicles per hour for a 3 berth station
750 Vehicles per hour for a 6 berth station
950 Vehicles per hour for a 9 berth station
1250 Vehicles per hour for a 12 berth station
1500 Vehicles per hour for a 15 berth station
All assume a normal time distribution for passenger boarding and deboarding in the
stations
http://www.skywebexpress.com/150f_capacity.shtml
You're absolutely correct that monorails do not work for spread out cities. That problem is the fundamental reason why mass transit cannot compete with cars. Traditional mass transit planners assume that a majority of commuters travel in a line (or corridor), when in fact, commuters in a city travel in a web.
Maglev, monorail, and lightrail all have the same fundamental problem. They are just glorified trains. They must stop at every stop, increasing travel time. They must cram passengers during peak times, making it less appealing than driving alone in an airconditioned car with your own music. They are horribly expensive, causing taxpayers to pay through the nose to subsidize it to keep it alive. They are terribly inefficient, since they run whether they are full or empty.
No transit system (even a snazzy one with mag-lev) will ever be successful unless it includes the following:
Point to point service (no transfers)
On demand service for little or no waiting time.
Fares competetive or lower than traditional transit and automobiles
A profitable business model (!)
Faster average times than cars
Privacy to travel without sitting crammed next to strangers
Forward thinking organizations are developing a transit system that has these attributes. It is called Personal Rapid Transit. The system is basically an elevated, light-weight rail that carries small (2-4 passenger) computer automated vehicles. It takes the problem of congestion and chops it up into smaller pieces. Taxi 2000 is a company in Minnesota that is now preparing to build a track. And the city officials in Cardiff, Wales have already begun building theirs. David Gow has put together an excellent website detailing why PRT is best suited for solving transit problems.
But until politicians and citizens in the US catch the vision, we will continue to suffer from congested freeways and inadequate mass transit.
California would do well to adopt open source after the deplOracle debacle. Oracle gave California Governer Gray Davis' campaign a $25,000 contribution a week after California state officials awarded Oracle with a $95 million NO-BID contract.
Slashdot Mirror
Because some websites won't let you in or give you content unless they think you have an IE browser.
Well, it isn't much different than getting on an elevator. How long does that usually take for even 8 people to get on it?
That's a great question and one of the best qualities of the system (I've been following its development for a few years now as an interested observer). The tracks are all one way so there is only a merge-type intersection to worry about. Unlike a train, the track doesn't move to divert the cars. Instead, each car has a type of "arm" with a wheel on each and that keeps it holding to the left or to the right. A good image of the switch is here:
http://kinetic.seattle.wa.us/~prt-q.html#gsmall
Since the switch mechanism is in the car, there is no overhead involved in switching the track.
> Also its a one way system so trips could be quite convoluted and time consuming.
Since it is a system of one way loops, there are some indirect trips, but the advantages are that it is a non stop trip. Here is another good example of how a car trip would compare with a PRT trip:
http://kinetic.seattle.wa.us/nxtlevel/prt/speedcom p.html
"No rear-end or merging collisions, because the vehicles are not operating independently. All are communicating with a central computer system that keeps tabs on traffic throughout the network. In principal it works like this: Cars continuously report their positions (every 40 milliseconds in Taxi 2000), and the central computer system tracks their location; the two sets of data are continuously compared. If a vehicle does something it's not supposed to do (such as follow too close, stop unexpectedly, a mechanical breakdown, or even if the vehicle's reporting signal is interrupted), the central system will send commands to fix or avoid problems-- "deccelerate for 3 seconds", for example. This system is always in operation, ensuring safe distances between vehicles whether on straightaways or at junctions."
With regard to getting out of a stopped car,
"There are over 70 elevated automated transit systems operating in the world today that prove that a vehicle stopping when not intended is a very rare event. If a vehicle does stop between stations, Central Control will talk with the passengers through an intercom system and guide the rescue operation. The vehicle behind will soft engage and push the disabled vehicle to the nearest station. In the very unlikely event that the vehicle can't be moved, a rescue team will come with a ladder and help the passengers out of the vehicle."
http://www.skywebexpress.com/1414_between_stations .shtml
yeah.. you've got the right idea. This is from teh skywebexpress website: Station Capacity (Stations can be sized from one to about 15 berths) 450 Vehicles per hour for a 3 berth station 750 Vehicles per hour for a 6 berth station 950 Vehicles per hour for a 9 berth station 1250 Vehicles per hour for a 12 berth station 1500 Vehicles per hour for a 15 berth station All assume a normal time distribution for passenger boarding and deboarding in the stations http://www.skywebexpress.com/150f_capacity.shtml
Maglev, monorail, and lightrail all have the same fundamental problem. They are just glorified trains. They must stop at every stop, increasing travel time. They must cram passengers during peak times, making it less appealing than driving alone in an airconditioned car with your own music. They are horribly expensive, causing taxpayers to pay through the nose to subsidize it to keep it alive. They are terribly inefficient, since they run whether they are full or empty.
No transit system (even a snazzy one with mag-lev) will ever be successful unless it includes the following:
- Point to point service (no transfers)
- On demand service for little or no waiting time.
- Fares competetive or lower than traditional transit and automobiles
- A profitable business model (!)
- Faster average times than cars
- Privacy to travel without sitting crammed next to strangers
Forward thinking organizations are developing a transit system that has these attributes. It is called Personal Rapid Transit. The system is basically an elevated, light-weight rail that carries small (2-4 passenger) computer automated vehicles. It takes the problem of congestion and chops it up into smaller pieces. Taxi 2000 is a company in Minnesota that is now preparing to build a track. And the city officials in Cardiff, Wales have already begun building theirs. David Gow has put together an excellent website detailing why PRT is best suited for solving transit problems.But until politicians and citizens in the US catch the vision, we will continue to suffer from congested freeways and inadequate mass transit.
Can you say quid pro quo?