However, as computer technology became more sophisticated, lightened, and small-sized, it was enabled to reach a practical level. However, there is no case put into practical use so far because of various reasons including shortage of economical efficiency and practicality.
Out of PRT cased, the Raytheon Co.’s PRT2000 is a typical one which has grown out from over a decade of systematic analyses of the problems of contemporary urban transportation, involvement in a variety of transit planning studies, and study of characteristics of new systems required to solve these problems.
One of the operational characteristics of the PRT system is a non-stop trip to destination. It is made possible by the use of off-line stations. Ridership is maximized if the stations are closely spaced in a network of interconnected guideways that eliminate the need for passengers to transfer from line to line. System capabilities and performance features of the typical PRT system are as shown in .
System Capabilities and Performance Features of the Typical PRT System
System Capabilities
Vehicle Capacity
|
4 passengers seated
1 passenger in wheelchair with seated companion
|
System Capacity
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Greater than 10,000 passengers per hour per direction for small systems. Site specific engineering analysis required.
|
Platform Capacity
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1,000-3,000passengers per hour(2 to 10 berth stations)
|
Wait Time
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Zero off-peak
Typically under 3minutes during peak demand
|
Trip Time
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2.5 to 3.5 minutes for a 1 mile trip
|
Performance Features Vehicle Speed |
30 mph(48kph) maximum forward speed
5 mph reverse speed, 15 mph(24kph) push speed for fault management.
| |
0.25g maximum, jerk limited @0.25g/s
| Emergency Braking |
0.25g to 0.5 fail-safe emergency braking
| Lateral Acceleration |
0.25 maximum, max. 0.25g/s using spiral transitions
Up to 6 degrees of superelevation.
| Headway |
Minimum separation of 2.5 seconds at 30 mph.
Actual headway varies with traffic patterns.
| Energy Use | 300W-Hr/Vehicle-mile |
Source : http://www.ee.vt.edu/perts/sscc/PRT2000.html
Ch. 13 Improvement of Administration Systems
13.1 Revolution of Urban Structure and Metropolitan Transportation Management
Major cities in the APEC region have formed huge urban systems with population increase and ensuing steady growth of surrounding satellite cities. Metropolitan traffic volumes, which are not bound by administrative districts, are increasing mainly by the commuter traffics between downtown and satellite cities. Concentration of population on metropolitan cities, and the expansion of satellite cities are common phenomena in the stage of economic development.
As urban population is increasing, the travel demand is increasing in scale and complexity due to the rapid increase in the number of cars and the expansion of living area. To handle this metropolitan type of traffics, the arrangement of metropolitan transport systems such as a highway, urban railroads, and long-route bus services, is necessary. However, urban transport policy is implemented on the basis of administrative districts, and, as a result, transport facilities and services for the metropolitan transport area are inefficiently provided and managed. Residents living in the peripheral area of the metropolitan area suffer from the inconvenient transport services.
The fundamental problem of the metropolitan transport system lies in the functional and jurisdictional fragmentation, and the ensuing conflict of interests or poor cooperation between them. For instance, bus operation permission or licensing is divided between different self-governing bodies, and schemes for highway management causes similar problems. Shortage of the arrangement of fragmented functions and organic linkages followed by the disconnection among inter-regional transport service leads not only to residents’ inconvenience in use of transport service but also to inefficiency in operation and unbalanced provision of regional transport service.
Accordingly, to provide efficient metropolitan transport service, it is needed to develop a metropolitan administration system, integrate transport administration, install a coordinating body between governments, and comprehensively manage transport system.
13.2 Types and Examples of Metropolitan Transport Administration System
Metropolitan administration systems are designed for two or more self-governing bodies to jointly counteract the problems of metropolitan administration with efficiency, to overcome the problems of expanding urban areas. There are 3 general ways of handling the problems of metropolitan administration as follows:
Re-arrangement of administrative districts;
Agreement between self-governing authorities;
Establishment of independent organization.
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