IIT KGP develops safer tool for railway interlocking


Railway Interlocking is a critical signalling system that prevents trains from conflicting movements through only allowing trains to receive authority to proceed, when routes have been set, lock and detected in safe combinations. Indian railways is moving towards Electronic interlocking which has much higher availability, reliability and safety. However, the configuration of an electronic interlocking (EI) equipment is a highly safety critical task. The executive software of the electronic interlocking equipment interprets the yard specific application logic while asserting the signal aspects. The application logic for a yard is typically developed by third-party vendors and rigorously tested, however errors in the application logic have been detected in commissioned electronic interlocking equipment – some leading to near catastrophic consequences. Formal verification methods, which can mathematically prove the conformance of the application logic with respect to yard specifi