MBSE & MBSA Projects
Representing aircraft system architectures in an MBSE environment in early design stages
I developed simplified representations of typical components found in aircraft flight control system architectures. These simplified models are then compiled into a catalog of generic elements that can be brought into the modelling environment as required. These generic elements are modelled at a level of granularity that capture power and data flows required for early system architecting decisions. The method is implemented using the Capella MBSE Tool and the ARCADIA methodology.
Enabling automated fault tree assessment using simplified system descriptions for early system architecture design stages
This project focused on developing a capability of automatically generating fault trees from a simplified description of aircraft system architecture. This type of early fault tree assessment enables safety to be considered in the early stages of system architecting.
A simple description of the system architecture based on generic elements, as described in this paper is used as the starting point. The Neo4J arrows application is used to build a network graph based model of the architecture. This model is imported into the NetworkX python package where the type of exchanges such as power and control between different components are identified and used to automatically build a safety model in AltaRica. The safety model is then automatically executed to generate a fault tree file which is visualized using the ArbeAnalyste tool.
This tool has been successfully deployed to model unconventional aircraft system architecture and features ease of modelling and the ability to make changes quickly and to obtain immediate safety insights during early design stages.
Linking MBSE specification models to physics-based evaluation and sizing models in an MDAO workflow to support system architecting decisions in early design stages.
I developed a method to derive input parameters stored in an MBSE architecture specification and transfer them as inputs to a system sizing model integrated into an MDAO workflow. The approach focuses on first storing input parameters using the Property Value Management Toolkit in the Capella MBSE Tool and then inspecting the underlying metamodel file to extract those parameters. A CPACS file is used as an intermediate medium of exchange between the specification model and the MDAO workflow.
In this project the parsing of the metamodel was performed manually but could be automated. However, as of 2021, the pycapellambse tool can now be used to parse the model and automatically extract all relevant parameters attached to any element in the specification model.
A safety-focused systems architecting framework for aircraft conceptual design
This project was in collaboration with Bombardier and a consortium of European partner organizations under the AGILE 4.0 project. Here, I developed a framework to integrate elements of the formal aircraft system safety assessment process (ARP4761A), within the conceptual design stage of aircraft development.
The framework shown below integrates knowledge-based safety analysis to help filter a design space of architecture candidates and then enables the system architect to model and evaluate the safety of selected architectures in an interactive manner. The simplified modelling approach can help the architect collaborate early with safety experts in analyzing an architecture. A visual overview of the framework is shown in the image below.
The framework I developed also overcomes some of the drawbacks of existing approaches by integrating the simplified architecture representation used for early safety assessment activities with formal model-based system architecture representation in an MBSE environment. The MBSE environment then supports a model-driven FHA to further capture safety requirements.
This approach helps avoid siloed activities and unifies safety-driven system architecting activities in conceptual design with formal system architecture specification in an MBSE environment which then can be used for detailed safety assessment as the architecture granularity increases in subsequent design stages.
A description of the framework is provided here.