Operating requirements of an automatic railway

Our age is called the age of automation. Indeed, automation is increasingly applied to various branches of industry and research. Automatic control of production processes by means of computing machines has prepared the way for the application of computing technique to railroad transport.

The main justification in seeking a fully automatic railway system must be economic. A system has to give a service at least equivalent to, and preferably better than, that with a conventional system but lower cost. The term "service" itself includes the following components:

1. Flexibility: the conventional railway is flexible in the number of destinations to be served, in the variations of loading, speed and frequency that can be imposed at short notice to meet variations and demand. In practice, it will seldom operate over the whole system exactly in accordance with a predetermined plan.

2. Reliability: any fully automatic system must be at least as reliable, mechanically and electrically, as that which it replaces. But, what is equally important, in the event of any failure it must be possible to overcome the effects of such a failure in such a way as to cause the least possible disturbance to the system as a whole.

3. Safety: it goes without saying that an automatic system must incorporate standards of safety equally high as those in existence before. Any failure of a piece of equipment which forms part of the control mechanism must be on the "safe" side.

The advantages to be achieved by automatic train operation may be summarized as follows:

- Regularity of service, deriving from uniformity to driving technique,

- reduction in minimum headway achievable and an increase in the maximum line capacity,

- maintenance of timetabled performance within minimum possible energy consumption,

- enforced observance of speed restrictions,

The ability to provide for automatic recovery from service delays, the possibility of reducing operating manpower.

It is true that in many respects the automatic control can do no better than a good human driver: indeed it is sometimes alleged that a good human driver can, in some respects at least, exceed the performance of the automatic controls. Experience shows that on average the superlatively good human driver is likely to be followed by one of less than average ability and the net effect of the first man's superior driving is to widen the gap between the two trains to as extent which reacts to the increasing determinant of the following train.

The sphere of application of computing machines in general and their application to railroad transport in particular is practically unlimited. Each year the traffic volume on our railway grows. It is necessary within a very short period of time to prepare hundreds of traffic schedules, to determine intensity of railway traffic, and register goods. So, nowadays computers are being widely used to control the transportation process.

The general structure of the automated system of railway control is considered as a large system including a number of smaller subsystems. Electronic computers are now most widely used to automate marshalling yards operations. Under the automatic system developed in our country the sorting of trains in some marshalling yards has been computerized. To facilitate the sorting of trains the computers may be installed directly at the yards themselves.

High accuracy of calculations is needed at the Computer Centre. That is why before the beginning of a working day each computer is carefully examined and its units are regulated. When examined, the computer units are ready for operation.

We are continuously getting nearer to the all-machine age. Planning the operation of trains is not the only field of computers application on railways. Electronic computers are being introduced into other branches of railway engineering as well. Paying wages, tickets reservation, designing locomotives and cars, is controlling processes at works and factories producing machinery.

The automated system called "Express", which is intended for booking railway tickets, has been developed. Passengers do not wait for a ticket to a train. With the aid of a computer, the booking clerk serves up to five people per minute.

The electronic brains in the present form have freed man from a great number of calculations. But now specialists are working on designing new, better and quicker electronic computers. Their wide use on transport will turn our railways into the most reliable and efficient means of communication.

 

Exercise 1