Autonomous decentralization concept and its application to railway control systems

An autonomous decentralization concept based on a biological analogy has been developed. It yields a higher degree of reliability and flexibility by designing system structure, control and expansion on the assumptions that even if any subsystem fails, the other subsystems will continue working without shutting down. A subway transit system based on this concept has been realized. The functions of power supply control, train traffic control, train maintenance and dispatching are decentralized so as to prevent local trouble from affecting the whole system and to maintain transportation service. The autonomous decentralized concept has actually been applied as follows. Station control systems connected to an autonomous decentralized loop network system (ADL), are autonomous subsystems equivalent with others, having timetable information for each station. They can regulate train traffic based on only local information about how trains have been delayed or will be delayed.