An Algorithm to Generate a Railway Interlocking Table

Abstract

A railway interlocking table is a document describing the functional specification of an interlocking device which is responsible for the safe and efficient train operations. Conventionally, the signal engineer makes the most of his expertise to produce an interlocking table. However, since the expertise involved does not always produce the same interlocking table, beginners may sometimes have difficulty understanding it. In the past, some attempts at automatic generation of interlocking table were made but the core of the expertise has always been left untouched as a hard nut to crack.
This paper proposes a train route setting principle, based on which two algorithms, “lock algorithm” and “compound algorithm, ” have been established to generate a complete interlocking table. The expertise can successfully realized in these algorithms. The man-made and machine-made interlocking tables are compared to find out their differences. It is concluded that some existing interlocking tables can be improved and the algorithms can contribute to several practical purposes of interlocking table.