Aspect-Oriented Approach to Modeling Railway Cyber Physical Systems

The development of railway cyber physical systems is a challenging process. Railway cyber physical systems involve interactions between train controllers, communication networks, and physical world. In railway cyber physical systems, the behavior of the physical world such as the velocity, flow and density are dynamic and continuous changing with time while the process of communication and calculation in railway cyber system is discrete. Non-functional requirements address important issues of quality and restrictions for railway cyber physical systems. The high need for quality is beyond dispute as human life may be endangered if a railway controller is malfunctioning. The struggle for high-quality software development methods is of highest importance in railway cyber physical area. Architecture Analysis and Design Language (AADL) is a standard architecture description language to design and evaluate software architectures for embedded systems already in use by a number of organizations around the world. In this paper we present our current effort to extend AADL to include new features for separation of concerns of railway cyber physical systems, we extend AADL in spatial aspect, dynamic continuous aspect, formal specification aspect. Finally, we illustrate the proposed method via an example of railway cyber physical system.