Improved Grade Crossing Safety with In-Pavement Warning Lights

摘要

This is a second final report on the work done under this grant. A first report was written and submitted that included a description and copies of publications under grant funding. At the time, however, I did not know that a separate report was required because the grant number had changed during the 3-year period of the grant. This second report contains a more detailed description of the safety analysis techniques and tools that have been developed for a state-based requirements specification language called Requirements State Machine Language (RSML). These tools include a simulator that allows for forward and backward execution of RSML specifications, a fault tree generator that is based on backward simulation, and tools to check for consistency and completeness of specifications. An example requirements specification of an automated highway system design is described and the functionality of the tools are demonstrated on the model. The report also contains a copy of a dissertation on a new safety analysis technique, called Software Deviation Analysis (SDA) that was partially supported by this grant. The technique allows analysis of the behavior of the model in the presence of deviations from expected inputs, i.e, how the system would work in an imperfect environment.