Questions & Answers

What is Personal Rapid Transit?

According to the Advanced Transit Association, a PRT system has:

1. "Fully automated vehicles capable of operation without human drivers.
2. Vehicles captive to a reserved guideway.
3. Small vehicles available for exclusive use by an individual or a small group, typically 1 to 6 passengers, traveling together by choice and available 24 hours a day.
4. Small guideways that can be located aboveground, at groundlevel or underground.
5. Vehicles able to use all guideways and stations on a fully coupled PRT network.
6. Direct origin to destination service, without a necessity to transfer or stop at intervening stations.
7. Service available on demand rather than on fixed schedules."

No wait, non-stop, always available!

What is Personal Automated Transport?

Personal automated transport (PAT) is a newer term which is intended to be somewhat broader than PRT and may include dualmode as well as PRT.  Kirston Henderson of MegaRail was one of the first to use the term. "Transit" means only "mass transit" with large vehicles to most people.  "Rapid" is seriously ambiguous - how fast is rapid?  PAT implies a computer-controlled system which can operate economically while carrying one person per vehicle.  Small elevators (lifts) could be considered to be  PAT, although we don't know if anyone is using PAT to include elevators.

What are the specifications of the Higherway System?

Since the Higherway system is in the preliminary design and analysis stage there are no firm specifications yet. However, the following table gives some numbers which can be considered to be requirements, goals, and estimates. Most of these have been published in the ATRA report, "Personal Automated Transportation: Status and Potential of Personal Rapid Transit".

Guideway Dimensions

	Height	Width	Length
Acceleration & Through Tracks	1.0 meter	0.44 meter	22 meter sections
Ramp Tracks	0.65 meter	0.44 meter	up to 22 m sections
Minimum Curve Radius		5.5 meters
Skyprint (looking up at 45 degrees)	2 m for two tracks

Vehicle Dimensions

Vehicle	Height	Width	Length	Gross Vehicle Mass	Empty Vehicle Mass
Dove	1.8 m	0.8 m	4.5 m	400 kg	200 kg
Baz	0.7 m	0.38 m	4.5 m	900 kg	100 kg
Pelican	1.7 m	1 m	4 m	800 kg	400 kg
Owl	1.9 m	1.2 m	4.5 m	800 kg	300 kg
Pheasant	1.3 to 1.5 m	1.2 m	4 m	800 kg	570 kg
Quail	1.2 to 1.5 m	1.2 m (guideway) 1.8 m (street)	4 m	750 kg	600 kg


Power

Guideway ­ 600 - 750 VDC with 360 Hz AC ripple, unregulated

Vehicles - Two permanent magnet brushless DC motorwheels, rated 25 kW each for Dove, 50 kW each for Baz. Estimated power consumption on level track at 45 m/s is 5 kW for the Dove, 10 kW for the Baz when carrying a Pelican. The motor controllers operate on the unregulated DC power from the guideway. The Dove and Baz motorwheels are the same size, but the Baz achieves a higher power rating with more liquid cooling. Depending on application and location the Dove motorwheels may be air cooled or liquid cooled. Air conditioning, heating, and compressed air supply motors may also use unregulated DC power. Everything else - electronics, motors for idler wheels, guidewheels and stabilizer wheels will be operated from batteries charged by power supplies from the AC ripple.