Knowledge-based technology for controlling railway stations

The designs and implementations of two expert systems applicable to any railway station, the automatic train protection (ATP) design expert system (ADES), which automatically designs ATP systems, and the stationmaster assistant (SMA) which helps stationmasters choose safe routes, are discussed. These systems use shared knowledge to explicitly represent ATP systems and routes, making the systems easily understood, structured, and maintained. A knowledge-based approach enables the system to explain their decisions. The explanation module in ADES provides why and how facilities, both to simplify the maintenance and validation of the knowledge base and to train new experts on the ATP system functions. SMA operators can ask why a route was or was not feasible. When the stationmaster asks for currently feasible routes, the SMA presents the feasible routes, then the occupied routes, and then the unfeasible routes with explanations.<>