The MDM-CPPS Framework: GitOps-enabled Multi-Domain Modeling in Cyber-Physical Production Systems Engineering

Abstract

Engineering Cyber-Physical Production Systems (CPPSs) requires the collaboration of engineers from different domains. Usually, engineers work in domain-specific work environments. The management of such domain-specific views and the artifact exchange between them is challenging because of diverging concepts. To improve the overall engineering process a holistic view of the engineering concepts and common model should be established. In this paper, we introduce a method for Multi-Domain Modeling for CPPS (MDM-CPPS) that allows engineers to define local concepts in a distinct view and negotiate a holistic view based on common concepts in a collaborative effort. The method then allows to independently change the properties in the domain-specific views and merge them back in a structured process based on DevOps and GitOps practices. To this end, we provide an architecture that incorporates a toolchain consisting of a Domain-specific Language (DSL) for modeling domain-specific concepts and common concepts by a Language Server Protocol (LSP) supported editor, and services to generate domain-specific views on the common model as well as delta comparison and merge capabilities automated by a continuous integration pipeline. Changes to the domain-specific model are semantically analyzed and the impact on other domains is calculated before the changes are seamlessly integrated into the common model. The change impact resolving process is managed using issues and their workflow in an issue tracker and a Git-based source code repository. We follow the Design Science methodology to address the challenges of the multi-domain modeling in CPPS, introduce and evaluate the MDM-CPPS method, and propose the MDM-CPPS architecture and toolchain. We evaluated our method and architecture with a feasibility study based on a use case from the industry. The proposed MDM-CPPS approach provides a) the means of common system understanding, b) a reduced effort of change coordination by using DevOps practices, such as GitLab continuous integration functionality, and c) the management of assets of the CPPS project using GitOps practices.