Can a Dual-Mode System be Implemented? A Response to the Problems Raised by Hopkins


Palle R. Jensen, RUF International, Denmark

May 2000

Dr. Hopkins is rather pessimistic about implementation of new systems within transportation. I will argue that there is a chance with the RUF Dual-Mode system. In my arguments I will refer to the key points in Dr. Hopkins article.

The Chicken-and-Egg problem:

I agree that it will be very difficult to start a new system made for privately owned cars only. No investor will use billions of dollars creating a guideway system without knowing for sure if anybody will buy the vehicles for it. The car development could be started, because the horse waggons had created a start network of roads.

This problem is especially severe when using Maglev technology because the guideway is much more expensive than the simple RUF guideway.

The solution is to start the system as a public transport system where the guideway is used by public vehicles. In the RUF system we have public rufs to be let from the operator and driving as cars or as PRT vehicles on the guideway. We also have small electric Dual-Mode busses (maxi-ruf) with 10 seats. Maxi-rufs can create a very attractive public transport system with door-to-door service and a very high level of service. It is started by the operating company which owns the guideway as well as the vehicles.

Any city need a public transport system in order to supply mobility to elderly people, children and people who cannot afford a car. The public RUF system can solve this problem in a way which also attracts new customers.

Gradually the car manufacturers begin creating vehicles (rufs) for the system and people buy them because they get an immediate advantage by using the guideway. They get a faster commute with a predictable travel time. They get some extra time which can be used to work on-line while they are connected to the Internet via the guideway. They earn money while they commute. The rumor about this attractive possibility will spread very fast and many more will buy the vehicles.

The interface between vehicles and guideways

Dr. Hopkins argue that tight integration between guideway and vehicles will make improvements difficult.

I agree that some of the PRT designs suffer from these problems. In the RUF concept we try to keep the interface very simple in order to ensure high reliability. The interface will be defined in an open standard: The RUF Standard which will allow different car manufacturers to create different vehicles for the system. Also rail manufacturers can make their own design as long as they comply with the RUF Standard.

The car concept is extremely flexible because of the very simple interface: a flat surface. This is an advantage, but also a limitation.

When things are normal, a flat surface is OK. When braking is needed, a flat surface is a problem. The center of gravity is placed above and behind the point where the braking forces are pulling in the vehicle (under the front wheels). This creates a dangerous situation. The car becomes unstable and unsteerable. Many people have lost their lives because of this unstability caused by a very simple interface.

On the RUF guideway, braking is completely stable and safe because the center of gravity is placed just in front of the place where the emergency braking force is pulling the vehicle. The rail brake is pressing from both sides against the top of the triangular rail. The braking situation is ideal.

The real issues are understanding real transportation needs

I agree that this is essential and very complex. Many suggested transport solutions originate from technology experts who would like to see their favourite technology used in a huge market as transportation.

The RUF technology has started from schratch, trying to rethink transportation from the users perspective. It was obvious to me that the qualities of a car have to be included in the concept. It was also obvious that when people in Los Angeles waste time in the order of magnitude of $10 billion per year, a more efficient mode of transportation was needed. The very slender guideway in the RUF system represents an extremely efficient transport corridor using the available ROW in the best possible way.

Combining the car concept with an efficient guideway will give the users signifcant benefits and at the same time the vehicle is a car which you would love to show your friends.

The society gain advantages too. The safety will increase, the traffic noise will decrease and the oil dependance will be reduced. Electric vehicles will be implemented without range limitations (power from guideway).

Dr. Hopkins is pessimistic about the reactions from decision makers. My experience is more positive. I have been approached several times by politicians who are eager to see RUF realized. One city offered RUF International all support in order to be the first in the world to have a RUF system. Other politicians have been equally positive. The problem has been, that we have not been able to demonstrate. This will change in the near future.

With support from Danish politicians, companies and institutions, we are ready to open our test track in Copenhagen on June 9th 2000. I would be happy to give you a VIP demonstration if you come to Denmark.

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Last modified: May 18, 2000