Personal Rapid Transit in New Zealand - Future Transit Now

The problem of precise longitudinal control of vehicles so that they follow predetermined time-varying speeds and positions has been solved. To control vehicles to the required close headway of at least 0.5 sec, the control philosophy is different from but no less rigorous than that of railroad practice. The preferred control strategy is one that could be called an "asynchronous point follower." Such a strategy requires no clock synchronization, is flexible in all unusual conditions, permits the maximum possible throughput, requires a minimum of maneuvering and uses a minimum of software. Since wayside zone controllers have in their memory exactly the same maneuver equations as the on-board computers, accurate safety monitoring is practical. The paper discusses the functions of vehicle control; the control of station, merge, and diverge zones; and central control.

Courses of Study for Engineers preparing to work on PRT Design.

Covers

• Systems Engineering applied to PRT Systems
• The Simulation and Control of PRT Systems
• The Design of a PRT System

A comprehensive method for calculating and measuring Dependability of Personal Rapid
Transit systems is derived and compared with the more common measure called Availability. Availability is the percentage of all revenue trips that are completed without interruption. It does not take into account the duration of delays of the passengers because of the difficulty of gathering the necessary information in conventional transit systems.

In PRT systems, vehicle-hours of travel and of delay relate in a statistically simple way to personhours of travel and of delay. Therefore, in such systems, it is practical to use the performance measure called Dependability that takes into account the inconvenience of people as a result of delays. To form a bridge to present practice, it is recommended that both measures be calculated and compared in forthcoming PRT systems. With today's computer systems, this is easily accomplished.

This paper compares the middle two options among the spectrum listed above. Alternative #3 will be referred to hereinafter as "Single Mode" or SM. Alternative #4 is called "Dual Mode" or DM. DM has the advantage over SM for auto drivers that the same vehicle may be taken for any trip, just as occurs now with one's own automobile. In many respects, DM is much like the system envisioned by advocates of alternative #5, an Intelligent Vehicle Highway System, except that special narrower guideways could be used for the automated guideway portion of the trip.

The paper reviews the evolution of the PRT concept from its modern beginning in 1953.  The early inventors, the projects, and the response of government are discussed.  PRT activity diminished to almost nothing by 1980, but then revived strongly as a result of activity by the Northeastern Illinois Regional Transportation Authority.  Their interest ignited enthusiastic activity on a growing front to the point that today one can truly say that the concept is coming of age