The goal of the paper is the integration of safety analysis in a model-based systems engineering approach to ensure consistency between system design and safety artifacts. This integration permits the continuous improvement of the structure and behavior of the system. It also reduces system development time and prevents late detection of errors. To reach this purpose, the SafeSysE methodology is extended. In SafeSysE, a preliminary Failure Mode and Effects Analysis (FMEA) is automatically generated from a SysML model, and this FMEA is then completed by the safety expert but no further development was proposed. The contribution of this paper is to suggest recommendations based on the FMEA analysis in order to enhance the system design and make it comply with safety requirements. First, an updated system structure that may contain redundancy is proposed. Then, a redundancy profile is used to enrich the system model with redundancy information, which will allow the generation of a dynamic fault tree considering the system behavior. Finally, the generated dynamic fault tree should be analyzed in order to create a state machine diagram that describes the behavior of the system. The created state machine with an internal block diagram will help the system designers to better understand the system dysfunctions by simulating the system. The proposed methodology is applied to an Electro-Mechanical Actuator system which is used in the aeronautics domain.

The development of a mechatronic system involves different designers having various viewpoints on the overall system to handle its complexity. Consequently, multiple models are created from a variety of domains such as mechanical, electronic, and software engineering. These models use different formalisms, modeling languages, and tools to address specific concerns. The major challenge of this approach is to identify and solve any potential inconsistency between models in order to minimize costs and development time before the verification and validation phases. This paper proposes a new collaborative methodology to maintain consistency between different engineering disciplines at an early stage of the development cycle of mechatronic systems based on Model-Based Engineering (MBE). We apply a model synchronization approach to actively check for model consistency in a continuous way during the multidisciplinary design process. As a novel contribution of this paper, we demonstrate how model transformation techniques can be employed; firstly, to abstract various engineering models in a common formalism based on graph theory and, secondly, to update models with appropriate changes evaluated by a project manager. We also show how to detect the differences automatically, and we discuss where designer decisions are essential.

Nowadays, several manufacturing systems are evolving towards a greater collaboration between human and robots. The development of such systems requires integrated design tasks involving many disciplines and domains such as systems engineering, safety analyses and multi-physics. Furthermore, the increasing presence of multiple and structured requirements makes the use of models inevitable during the designing phases and also strongly helpful during other phases of the system life-cycle. Besides, for a better efficiency, there is an increasing demand to have a Digital Twin of the system to be used for different purposes such as design improvements by playing different scenarios, virtual commissioning and controlling maintenance activities. In this paper, we first summarize the research context, the reference methodologies, and the emerging needs for Digital Twin creation. Then, we apply a design approach including Model-Based Systems Engineering (MBSE), Model-Based Safety Assessment (MBSA) and multi-physics modeling for the design of a collaborative workplace for the assembly of Electro-Mechanical Actuators on an aircraft wing. An operational flow to integrate MBSE, MBSA and multi-physics modelling activities is provided. Then, after having identified some relevant scientific barriers, we provide a meta-model for system models integration within a digital twin framework.

Systems are getting increasingly complex and challenging to design. For safety-critical systems, the integration between model-based systems engineering and model-based safety assessment to improve the choice of the system architecture since the early design stage becomes a necessity. One of the integration solutions is to generate fault trees (FTs), either static or dynamic, directly from the system description. In this paper, we are particularly interested in the generation of the dynamic fault trees (DFTs) of the systems that contain redundancies, which is widely used in safety-critical systems to enhance their reliability. The goal of this paper is, first, to propose a redundancy profile and, second, to automatically generate the DFTs from system models. Since errors are propagated via input and output ports of the components, the generation process starts with a depth-first search graph traversal through the systems modeling language internal block diagram of the system. This diagram is considered as a multidirected graph in order to detect the external inputs, the nonredundant components, the switch components, and the redundant components of the system. Then, the redundancy information incorporated in the system model is used to generate the appropriate combinations of the FT. This FT is represented in a suitable format that can be studied using FT analysis tools, for both qualitative and quantitative safety analyses.

In recent decades, there has been a significant increase in systems’ complexity, leading to a rise in the need for more and more models. Models created with different intents are written using different formalisms and give diverse system representations. This work focuses on the system engineering domain and its models. It is crucial to assert a critical system’s compliance with its requirements. Thus, multiple models dedicated to these assertions are designed, such as safety or multi-physics models. As those models are independent of the architecture model, we need to provide means to assert and maintain consistency between them if we want the analyses to be relevant. The model synchronization methodologies give means to work on the consistency between the models through steps of abstraction to a common formalism, comparison, and concretization of the comparison results in the original models. This paper proposes a mathematical framework that allows for a formal definition of such a consistency relation and a mathematical description of the models. We use the context of category theory, as this is a mathematical theory providing great tools for taking into account different abstraction levels and composition of relations. Finally, we show how this mathematical framework can be applied to a specific synchronization methodology with a realistic study case.

For a mechatronic system, the lack of robustness is mainly due to an ignorance of variability, which is unavoidable in every designed system at all stages of system development and during its life cycle. In fact, the inherent imperfections of manufacturing processes and operational variations such as material wear or multiphysical effects (thermal, vibrations, etc.) involve parametric variations, which can degrade the proper system function. To ensure a high level of quality and to improve design robustness, the deviations between actual and target definition should be restricted by specified tolerances. Moreover, it is important to understand the relationship between parameter deviations and system behavior. Thus, in this article, a variational approach is proposed to identify performance sensitivity to parameter deviations in a mechatronic system and to determine influential parameters that affect significantly the proper functioning of the system and its behavior. Furthermore, this approach is used to specify the admissible parameter deviations for which the given specifications can be guaranteed. The complete approach is applied to an example in the aeronautic field: an electromechanical actuator driving an aircraft primary flight control surface (aileron).