Model-Driven Engineering for Building Automation Systems

Abstract:
Integrating building automation systems (BASs) into the Internet is becoming increasingly important due to the upcoming Internet of Things (IoT) paradigm. Nonetheless, a lot of different standards and technologies in the building automation (BA) sector have to be kept in mind. An automated process needs to be defined in order to enable an efficient and common way of integrating BA networks into the IoT. Gateway technologies, like Open Building Information Exchange (oBIX), offering Web services (WSs) can be used as interfaces between BASs and remote building management systems (BMSs). Model-Driven Engineering (MDE) provides a model-centric solution to establish an automated integration process by defining appropriate modeling languages and transformations. In this underlying thesis, OMG-s MDE initiative, Model-Driven Architecture (MDA), is utilized to introduce two modeling languages as metamodels. According to a four-layer architecture, these metamodels conform to the Meta Object Facility (MOF), their common metametamodel. A metamodel provides concepts to create models that represent snapshots of systems. The BAS metamodel is used to define platform independent models (PIMs). In this case, the BA network is mapped to abstract, technology independent models. On the other hand, the oBIX metamodel defines platform specific models (PSMs). The taken approach uses oBIX as target technology for the integration of BASs. The transformation process, which comprises three phases, is specified based on the developed modeling languages. First, the BAS is mapped to a PIM. This step is either done manually or automatically by means of available engineering data. The actual MDA workflow starts with the existence of a PIM. Afterwards, the PIM is converted to a PSM via a model-to-model (M2M) transformation, and finally, a model-to-text (M2T) transformation generates executable source code for the target platform on the basis of the PSM. Additionally, a proof of concept implementation, which is based on the Eclipse IDE and the oBIX integration middleware IoTSyS, is presented. The Eclipse Modeling Framework (EMF) and other MDA extensions for Eclipse (OCL Tools, Xpand, QVT Operational) are used for the realization. The different parts of the model-driven approach (models, metamodels, transformations) are separated into various Eclipse projects to form a modular structure, and the implemented concepts are evaluated by a case study. An experimental KNX network is integrated into an oBIX gateway implementation to show the functionality of the proof of concept implementation. Modeling of the BAS with the help of configuration data of the Engineering Tool Software 4 (ETS4) is discussed, as well. The functional capability of the developed, model-driven approach is pointed out in the evaluation.