Towards Improved Requirements Engineering with SysML and the User Requirements Notation

The Systems Modeling Language (SysML) is a popular and standardized UML profile for systems engineering applications. In addition to seven conventional UML diagram types, SysML supports requirement diagrams and tables that can be used to capture requirements, their attributes, and their relationships. However, several important concepts such as goals and contributions are not predefined in SysML, hindering the reasoning about tradeoffs and adaptation, especially in emerging socio-cyber-physical systems such as smart cities. In this paper, we provide a preliminary investigation of different ways of combining SysML with the User Requirements Notation (URN), a standard that focuses on the modeling and analysis of goals and scenarios. We argue that SysML and URN are complementary and synergistic, and that their combination enables new requirements modeling, analysis, and management opportunities for new types of systems. Examples of potential integration approaches are discussed, briefly assessed, and illustrated with existing tools for SysML, URN, and requirements management.