Domain-Specific Modelling for Human-Computer Interaction

Model-driven engineering (MDE) is an important enabler in the development of complex, reactive, often real-time, and software-intensive systems, as it shifts the level of specification from computing concepts (the “how”) to conceptual models or abstractions in the problem domain (the “what”). Domain-specific modelling (DSM) in particular allows to specify these models in a domain-specific modelling language (DSML), using concepts and notations of a specific domain. It allows the use of a custom visual syntax which is closer to the problem domain and therefore more intuitive. Models created in DSMLs are used, among others, for simulation, (formal) analysis, documentation, and code synthesis for different platforms. The goal is to enable domain experts, such as a power plant engineer, to develop, to understand, and to verify models more easily, without having to use concepts outside of their own domain. The first step in the DSM approach when modelling in a new domain is, after a domain analysis, creating an appropriate DSML. In this chapter, we give an introduction to DSML engineering and show how it can be used to develop a human–computer interaction interface. A DSML is fully defined by its syntax and semantics. The syntax consists of (i) the abstract syntax, defining the DSML constructs and their allowed combinations, captured in a metamodel, and (ii) the concrete syntax, specifying the visual representation of the different constructs. The semantics defines the meaning of models created in the domain. In this chapter, we show how two types of semantics (operational and translational) can be modelled using model transformations. Operational semantics gives meaning to the modelling language by continuously updating the model’s state, effectively building a simulator. Translational semantics defines mappings of models in one language onto models in a language with known semantics. This enables the automatic construction of behavioural models, as well as models for verification. The former can be used for automated code synthesis (leading to a running application), whereas the latter leads to model checking. We choose to specify properties for model checking using the ProMoBox approach, which allows the modelling of properties in a syntax similar to the original DSML. A major advantage of this approach is that the modeller specifies both requirements (in the form of properties) and design models in a familiar notation. The properties modelled in this domain-specific syntax are verified by mapping them to lower-level languages, such as Promela, and results are mapped back to the domain-specific level. To illustrate the approach, we create a DSML for modelling the human–computer interaction interface of a nuclear power plant.