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- Form U122-0394
- TRAIN.TXT
-
- Ada Information Clearinghouse, 1-800-AdaIC-11 (232-4211),
- 703/685-1477
-
-
- Ada in European Railroad Signaling and
- Train Control
- by Etienne Morel, Rational SARL
-
- The goal of the European Community is to unite disparate countries
- into an interconnected, multi-cultural economic community. What
- began as a local project in Paris to improve the operation and
- safety of the railroads, has evolved into a Europe-wide effort to
- provide a safe, smoothly-run transportation system that will become
- a symbol of European community.
-
- This French project, called Astree, is an effort to equip every
- train with position and transmission systems that will
- automatically provide location, speed, distance, switch,
- operations, and safety information about each train. France's
- national railroad organization, Societe Nationale des Chemins de
- fer Francais (SNCF), in charge of the project, has chosen Ada and
- Rational for developing the systems that will collect, analyze,
- monitor, and control this data.
-
- Astree's initial prototype consisted of 300,000 lines of C code,
- which was difficult to maintain and suffered reliability problems.
- Because Ada is recognized for its maintainability on large, complex
- development projects, Astree decided to start over using Ada.
-
- Astree's two main issues were safety and reliability of the
- software. Astree evaluated a number of solutions, including
- Digital Equipment Corp.'s DECAda solution, and found that the
- Rational solution provided the most complete offering of
- capabilities and integrated products to meet their needs. > I'd
- delete from "Astree" to the end of the paragraph, and put the >
- first sentence in with the previous paragraph.
-
- Approximately 15 software engineers will be working on the project,
- which is currently in the design phase. They are using the Rational
- Environment, Rational Compilation Integrator with DECAda, Testmate
- and Insight. The target system for the project is Digital Equipment
- Corp.'s VAX VMS and VAX/ELN using DECAda.
-
- The early version of Astree, due to be completed by mid- 1994, will
- control almost 100 trains over 600 kilometers of rail. By the turn
- of the century, it will be deployed over the entire territory, and
- even over Europe through the European Train Control System (ETCS)
- currently being developed in cooperation with Germany and other
- countries.
-
- Under the Astree project, each train will feature a train integrity
- control system and a computer that can control train speed and
- access data processing management and control centers across the
- territory through bi- directional radio link. Each vehicle will
- also have an identification tag which can be read from the ground
- for consistent train information.
-
- Other on-board equipment will include Doppler radars that measure
- the current speed and distance covered. Each train will have a
- microwave reader that reads the track by collecting data from
- position transponders that are placed along the track. An
- odometric unit will input the data from the sensors and calculate
- the position of the train in the network.
-
- All Astree operational centers are linked to each other and can
- query trains about their position and speed and determine the
- position of the switches. The centers rely on a computerized
- database that provides an accurate and comprehensive real-time
- picture of the network and trains and supports monitoring,
- route-setting, traffic control, and operational safety.
-
- Apart from numerous technical developments in system components,
- the Astree project calls for integrated functional tests aimed at
- progressively developing operational specifications. At present,
- the main Astree functions are undergoing tests in the Paris
- suburbs, on the Bondy-Aulnay line.
-
- A comprehensive test of system function is also being defined and
- will include the greater part of the lines in the Eastern Parisian
- region. If this test confirms expectations, detailed functional
- studies could be completed by 1996 with actual implementation on
- the network before the turn of the century.
-
- For more information, please contact Etienne Morel of Rational SARL
- in France at +33-1-47-17-41-77 or +33-1-47- 17-41-55 (fax) or
- emorel@rational.com.
-
-
-
- **********************
-
- The views, opinions, and findings contained in this report are
- those of the author(s) and should not be construed as an official
- Agency position, policy, or decision, unless so designated by other
- official documentation.
-
- Ada Information Clearinghouse (AdaIC)
- P.O. Box 46593
- Washington, DC 20050-6593
- 1-800-AdaIC-11 (232-4211), 703/685-1477, FAX 703/685-7019
- adainfo@ajpo.sei.cmu.edu; CompuServe 70312,3303
-
- The AdaIC is sponsored by the Ada Joint Program Office and operated
- by IIT Research Institute.
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