Avoiding unpredicted behaviour of large scale embedded systems by design and application of modelling rules

One big problem in integrating components of complex systems is unpredicted behaviour of one or more components and as a result of the whole system. To overcome this problem, modelling rules for models of a particular formalism are needed to avoid incompatibilities between models of different sources and misunderstandings between developers. We provide a pragmatic approach for designing and applying modelling rules for e.g. UML statecharts supported by different tools to avoid the problem of unpredicted behaviour. Therefore, one needs to understand the syntax and semantics of statecharts and the reasons for different behaviour of look-alike models. A statechart simulator called SCSim based on a modular semantics for statecharts helps to understand these differences and to find matching modelling rules. A tool called Rule Checker applies these rules on statechart models. Finally, we can check if a statechart is well designed according to this rules.