Apesar das novas e efetivas técnicas de engenharia de software, os projetos de desenvolvimento de sistemas estão propensos a ter os mesmos problemas que acometem o software de apoio à gestão. Entrega com atraso, acima do orçamento e não suprindo as reais necessidades dos usuários finais ou da organização que está financiando o desenvolvimento do sistema, são os principais problemas. Esse último problema é o que mais afeta o desenvolvimento de sistemas e é um desafio para que o desenvolvimento personalizado seja uma solução real para várias empresas. Este trabalho apresenta uma proposta de método de gestão que auxilie a comunicação entre as atividades associadas à engenharia de requisitos e as atividades associadas à modelagem dos processos de negócio. Essa abordagem concerne à gestão e tratamento de requisitos de sistemas baseando-se em técnicas de engenharia de processos de negócios e de engenharia de requisitos, no processo unificado de desenvolvimento de software e na utilização de linguagens semi-formais e formais de modelagem, UML e SysML respectivamente. O método pretende mitigar os efeitos dos problemas de comunicação existentes entre os diversos integrantes de um projeto, com especial atenção para a comunicação entre a equipe de requisitos do projeto e os stakeholders responsáveis pela aceitação e aprovação do sistema. A pesquisa, com o apoio da apresentação de dois casos que ilustram o método de gestão proposto, permite concluir que é possível tornar mais efetiva e produtiva a comunicação entre os diversos envolvidos com o projeto, podendo resultar em um processo mais eficiente para a aceitação dos requisitos junto aos stakeholders. / Despite new and effective software engineering techniques, system development projects are likely to have the same problems that affect the management support software. Delivery delay, above budget and not fitting the real needs of end users or the organization that is funding the system development, are the most common problems. The latter problem is the one that most affects the systems development and is a challenge for the custom development to be a real solution to several companies. This work presents a proposal for a management method to help the communication between the activities associated with the engineering requirements and the activities associated with business processes modeling. This approach, concerns to the systems requirements treatment and management, is based on business processes engineering and requirements engineering, in software development unified process and in the use of semi-formal and formal modeling languages as UML and SysML, respectively. The method seeks to mitigate the effects of the communication problems among the project members, with special attention to the communication between the project requirements team and the stakeholders responsible for the system acceptance and adoption. The research, supported by the presentation of two cases which illustrates the proposed management method, has concluded that it is possible to make more effective and productive communication among members related with the project, which may result a more efficient process for the stakeholders requirement acceptance.

Les travaux de recherche menés au cours de cette thèse s'inscrivent dans le cadre de la modélisation, de la vérification et de la validation de systèmes complexes, critiques et multi-physiques. Ces travaux visent à combler l'écart d'abstraction entre les modèles haut-niveau, point de départ des processus MBSE (Model-Based Systems Engineering), et la simulation temps réel, clef de voûte des approches In-the-Loop. Dans ce contexte, nous proposons d'unifier, au sein d'un même modèle SysML, les aspects continus d'un système, permettant de générer de manière automatique un modèle Modelica de plus bas niveau directement exécutable (simulation), et les aspects discrets, permettant l'animation et la génération de tests par des solveurs de contraintes. Les travaux réalisés au cours de cette thèse ont permis l'étude et la réalisation d'une chaîne outillée originale permettant de simuler et de tester ce type de systèmes à partir de modèles SysML en contexte In-the-Loop. Cette démarche a été validée par deux cas d'étude concrets issus de la recherche. Le premier, issu du projet ANR Smart Blocks, nous a permis de mettre à l'épreuve la méthodologie de modélisation SysML dans le but d'effectuer des simulations de convoyeur sans contact (jets d'air). Le second cas d'étude, issu du projet Région GEOSEFA, nous a permis de valider l'approche complète (simulation et test) en contexte In-the-Loop. Celui-ci porte sur la conception et la validation d'un nouveau système énergétique hybride embarqué dans un hélicoptère. / The research conducted during this thesis fall within the scope of modeling, verification and validation of critical and complex systems. This work aims to bridge the gap between the abstract high-level models, starting point of the MBSE process (Model-Based Systems Engineering), and real-time simulation keystone of In-the-Loop processes. In this context, we propose to unify, within a SysML model, continuous aspects of a system, to automatically generate an executable Modelica model (simulation), and discrete aspects allowing animation and test generation by constraint solvers. The work done during this thesis allowed the study and the realization of an original tooled approach to simulate and test such systems from SysML models within a In-the-Loop context. This approach has been validated by two concrete case studies from research partners. The first, from the ANR Smart Blocks project, allowed us to assess the relevance of the proposed SysML modeling methodology in order to perform contact less conveyor simulations. The second case study, from the GEOSEFA Regional project has allowed us to validate the overall approach (simulation and testing) in a In-the-Loop context. It covers the design and the validation of a new energy hybrid system embedded in a helicopter.

Model-Based Systems Engineering in industry has been constantly increasing its presence within the aerospace industry. SysML is one such MBSE tool that shows complex system organization and relationships. The Horizon Simulation Framework is another MBSE tool, created by Cal Poly students, that gives users the ability to run “day-in-the-life” simulations of systems. Finding a way to link these two tools could allow systems engineers to reap the benefits of both. This thesis investigates the background and design process involved with developing the code that can convert an output file generated in SysML, into a format specifically made for the Horizon Simulation Framework. The goal was to create an interface that can allow users to model a system in SysML, and analyze the model and verify system requirements using HSF. Another goal was to expand the capabilities of the Horizon Simulation Framework by designing and develop a module that would allow users to define and analyze system-level requirements. To evaluate the effectiveness of both codes, the Aeolus example case was used. A SysML model of the system was created as the product of another thesis; SysML based CubeSat Model Design and Integration with the Horizon Simulation Framework. The Aeolus SysML model was converted and used as input in an HSF simulation. The SysML model simulation data was compared against those of the original test case. To test the requirement module, system level requirements were formulated within the Aeolus system and run in simulation, providing an analysis of the results. The results of the analysis confirmed a successful conversion of the SysML model into an equivalent HSF model and a successful analysis of system-level requirements.

An efficient system development needs reuse, traceability and understanding. Today, specifications are usually written in text documents. Reuse means a copy and paste of suitable specifications. Traceability is the textual note that references to affected requirements. Achieving a full context understanding requires reading hundreds of pages in a variety of documents. Changing one textual requirement in complex systems can be very time-consuming. Model-based systems engineering (MBSE) addresses these issues. There, an integrated system model is used for the design, analysis, communication and system specification and shall contribute to handling the system complexity. This paper shows aspects of this approach in the development of a wheel loader\'s attachment system. Customer requirements will be used to derive a specification model. Based on this, the author introduces the system and software architecture. The connection between requirement and architecture leads to a traceable system design and produces the huge advantage of MBSE.

At the present time, most systems engineers do not have access to cognitive work analysis information or training in terms they can understand. This may lead to a disregard of the cognitive aspect of system design. The impact of this issue is system requirements that do not account for the cognitive strengths and limitations of users. Systems engineers cannot design effective decision support systems without defining cognitive work requirements. In order to improve system requirements, integration of cognitive work requirements into the systems engineering process has to be improved. One option to address this gap is the development of a Cognitive Work Analysis (CWA) framework using Systems Modeling Language (SysML). The study had two phases. The first involved aligning the CWA terminology with the SysML to produce a CWA framework using SysML. The second was the creation of an instruction using SysML to inform systems engineers of the process of integrating cognitive work requirements into the systems engineering process. This methodology provides a structured framework to define, manage, organize, and model cognitive work requirements. Additionally, it provides a tool for systems engineers to use in system design which supports a user’s cognitive functions, such as situational awareness, problem solving, and decision making.

This thesis examines the feasibility of substituting the system input script of Cal Poly’s Horizon Simulation Framework (HSF) with a Model Based Systems Engineering (MBSE) model designed with the Systems Modeling Language (SysML). A concurrent student project, SysML Output Interface Creation for the Horizon Simulation Framework, focused on design of the HSF Translator Plugin which converts SysML models to an HSF specific XML format. A SysML model of the HSF test case, Aeolus, was designed. The original Aeolus HSF input script and the translated SysML input script retained the format and dependency structure required by HSF. Both input scripts returned identical results and thus validated the feasibility of linking SysML with HSF through the HSF Translator Plugin. A second SysML model of the Cal Poly CubeSat mission, ExoCube, was also designed and converted into an HSF input script. The ExoCube input script also retained the format and dependency structure required by HSF. This demonstrated that future SysML models can be used in conjunction with the HSF Translator Plugin to create a functional HSF system input script.

Yes / The agricultural industry has the potential to undergo a revolutionary transformation with the use of Internet of Things (IoT) technology. Crop monitoring can be improved, waste reduced, and efficiency increased. However, there are risks associated with system failures that can lead to significant losses and food insecurity. Therefore, a proactive approach is necessary to ensure the effective safety assessment of new IoT systems before deployment. It is crucial to identify potential causes of failure and their severity from the conceptual design phase of the IoT system within smart agricultural ecosystems. This will help prevent such risks and ensure the safety of the system. This study examines the failure behaviour of IoT-based Smart Irrigation Systems (SIS) to identify potential causes of failure. This study proposes a comprehensive Model-Based Safety Analysis (MBSA) framework to model the failure behaviour of SIS and generate analysable safety artefacts of the system using System Modelling Language (SysML). The MBSA approach provides meticulousness to the analysis, supports model reuse, and makes the development of a Fault Tree Analysis (FTA) model easier, thereby reducing the inherent limitations of informal system analysis. The FTA model identifies component failures and their propagation, providing a detailed understanding of how individual component failures can lead to the overall failure of the SIS. This study offers valuable insights into the interconnectedness of various component failures by evaluating the SIS failure behaviour through the FTA model. This study generates multiple minimal cut sets, which provide actionable insights into designing dependable IoT-based SIS. This analysis identifies potential weak points in the design and provides a foundation for safety risk mitigation strategies. This study emphasises the significance of a systematic and model-driven approach to improving the dependability of IoT systems in agriculture, ensuring sustainable and safe implementation.

Avec la plupart des méthodes formelles, un premier modèle peut être raffiné formellement en plusieurs étapes, jusqu'à ce que le raffinement final contienne assez de détails pour une implémentation. Ce premier modèle est généralement construit à partir de la description des besoins obtenue dans la phase d'analyse des exigences. Cette transition de la phase des exigences à la phase de spécification formelle est l'une des étapes les plus délicates dans la chaîne de développement formel. En fait, la construction de ce modèle initial exige un niveau élevé de compétence et beaucoup de pratique, d'autant qu'il n'existe pas de processus bien défini pour aider les concepteurs. Parallèlement à ce problème, il s'avère également que les exigences non-fonctionnelles sont largement marginalisées dans le processus de développement logiciel. Les pratiques industrielles actuelles consistent généralement à spécifier seulement les exigences fonctionnelles durant les premières phases de ce processus et à laisser la prise en compte des exigences non-fonctionnelles au niveau de l'implémentation. Pour surmonter ces problèmes, la thèse vise à définir un couplage entre un modèle d'exigences exprimé en SysML/KAOS et des spécifications formelles abstraites, tout en garantissant une distinction entre les exigences fonctionnelles et non-fonctionnelles dès la phase d'analyse des exigences. Pour cela, la thèse propose tout d'abord deux approches différentes (l'une dédiée au B classique et l'autre à Event-B) dans lesquelles des modèles formels abstraits sont construits progressivement à partir du modèle de buts fonctionnels SysML/KAOS. La thèse se focalise par la suite sur l'approche dédiée à Event-B afin de la compléter et l'enrichir en se servant de deux autres modèles SysML/KAOS qui décrivent les buts non-fonctionnels et leurs impacts sur les buts fonctionnels. Nous présentons différentes manières permettant d'injecter ces buts non-fonctionnels et leurs impacts dans les modèles abstraits Event-B déjà obtenus. Des liens de correspondance entre les buts non-fonctionnels et les différents éléments Event-B sont également établis afin de faciliter la gestion de l'évolution de ces buts. Les différentes approches proposées dans cette thèse ont été appliquées pour la spécification du composant de localisation qui est une partie critique d'un système de transport terrestre. L'approche dédiée à Event-B est implémentée dans l'outil SysKAOS2EventB, permettant ainsi de générer une architecture de raffinement Event-B à partir d'un modèle de buts fonctionnels SysML/KAOS. Cette mise en œuvre s'appuie principalement sur les technologies de transformation de modèles à modèles / With most of formal methods, an initial formal model can be refined in multiple steps, until the final refinement contains enough details for an implementation. Most of the time, this initial model is built from the description obtained by the requirements analysis. Unfortunately, this transition from the requirements phase to the formal specification phase is one of the most painful steps in the formal development chain. In fact, building this initial model requires a high level of competence and a lot of practice, especially as there is no well-defined process to assist designers. Parallel to this problem, it appears that non-functional requirements are largely marginalized in the software development process. The current industrial practices consist generally in specifying only functional requirements during the first levels of this process and in leaving the consideration of non-functional requirements in the implementation level. To overcome these problems, this thesis aims to define a coupling between a requirement model expressed in SysML/KAOS and an abstract formal specification, while ensuring a distinction between functional and non-functional requirements from the requirements analysis phase. For that purpose, this thesis proposes firstly two different approaches (one dedicated to the classical B and the other to Event-B) in which abstract formal models are built incrementally from the SysML/KAOS functional goal model. Afterwards, the thesis focuses on the approach dedicated to Event-B in order to complete it and enrich it by using the two other SysML/KAOS models describing the non-functional goals and their impact on functional goals. We present different ways to inject these non-functional goals and their impact into the obtained abstract Event-B models. Links of correspondance between the non-functional goals and the different Event-B elements are also defined in order to improve the management of the evolution of these goals. The different approaches proposed in this thesis have been applied to the specification of a localization component which is a critical part of a land transportation system. The approach dedicated to Event-B is implemented in the SysKAOS2EventB tool, allowing hence the generation of an Event-B refinement architecture from a SysML/KAOS functional goal model. This implementation is mainly based on the model-to-model transformation technologies

L’analyse de compromis d’un modèle système a pour but de minimiser ou de maximiser différents objectifs tels que le coût ou les performances. Les méthodes actuelles de type OOSEM avec SysML ou ARCADIA sont basées sur la classification ; il s’agit de définir les différentes variantes de l’architecture d’un système de base puis d’analyser ces variantes. Dans ces approches, les choix d’architecture sont contraints : la plateforme d’exécution et la topologie sont déjà figées. Nous proposons la notion de « points de décision » pour modéliser les différents choix du système, en utilisant de nouveaux stéréotypes. L’avantage est d’avoir une modélisation plus « compacte » des différentes variantes et de piloter l’exploration des variantes en utilisant des contraintes. Lorsque le concepteur définit l’architecture du système, des points de décisions sont insérés dans le modèle du système. Ils permettent de modéliser la redondance ou le choix d’une instance pour un composant, les variations des attributs d’un composant, ou l’allocation des activités sur les blocs. Les fonctions objectifs sont définies dans un contexte d’optimisation à l’aide du diagramme paramétrique de SysML. Nous proposons des transformations du modèle SysML vers un problème de satisfaction de contraintes pour l’optimisation (CSMOP) dont la résolution nous permet d’obtenir l’ensemble des architectures optimales. Cette transformation est implantée dans un démonstrateur (plug-in Eclipse) permettant une utilisation conjointe de l’outil Papyrus et de solveurs, disponibles sous forme de logiciels libres. La méthode est illustrée avec des cas d’étude constitués d’une caméra stéréoscopique puis d’un drone, l’ensemble étant modélisé avec Papyrus. / Finding the set of optimal architectures is an important challenge for the designer who uses the Model-Based System Engineering (MBSE). Design objectives such as cost, performance are often conflicting. Current methods (OOSEM with SysML or ARCADIA) are focused on the design and the analysis of a particular alternative of the system. In these methods, the topology and the execution platform are frozen before the optimization. To improve the optimization from MBSE, we propose a methodology combining SysML with the concept of “decision point”. An initial SysML model is complemented with “decisions points” to show up the different alternatives for component redundancy, instance selection and allocation. The constraints and objective functions are also added to the initial SysML model, with an optimiza-tion context and parametric diagram. Then a representation of a constraint satisfaction problem for optimization (CSMOP) is generated with an algorithm and solved with an existing solver. A demonstrator implements this transformation in an Eclipse plug-in, combining the Papyrus open-source tool and CSP solvers. Two case studies illustrate the methodology: a stereoscopic camera sensor module and a mission controller for an Unmanned Aerial Vehi-cle (UAV).

Vérification Formelle et Incrémentale de Spécifications SysML pour la Conception de Systèmes à Base de ComposantsLe travail présenté dans cette thèse est une contribution à la spécification et la vérification des Systèmes à Base de Composants (SBC) modélisé avec le langage SysML. Les SBC sont largement utilisés dans le domaine industrielet ils sont construits en assemblant différents composants réutilisables, permettant ainsi le développement de systèmes complexes en réduisant leur coût de développement. Malgré le succès de l'utilisation des SBC, leur conception est une étape de plus en plus complexe qui nécessite la mise en {\oe}uvre d'approches plus rigoureuses.Pour faciliter la communication entre les différentes parties impliquées dans le développement d'un SBC, un des langages largement utilisé est SysML, qui permet de modéliser, en plus de la structure et le comportement du système, aussi ses exigences. Il offre un standard de modélisation, spécification et documentation de systèmes, dans lequel il est possible de développer un système, partant d'un niveau abstrait, vers des niveaux plus détaillés pouvant aboutir à une implémentation. %Généralement ces systèmes sont faits plus grands parce qu'ils sont développés avec des cadres logiciels.Dans ce contexte nous avons traité principalement deux problématiques.La première est liée au développement par raffinement d'un SBC modélisé uniquement par ses interfaces SysML. Notre contribution permet au concepteur des SBC de garantir formellement qu'une composition d'un ensemble de composants élémentaires et réutilisables raffine une spécification abstraite d'un SBC. Dans cette contribution, nous exploitons les outils: Ptolemy pour la vérification de la compatibilité des composants assemblés, et l'outil MIO Workbench pour la vérification du raffinementLa deuxième problématique traitée concerne la difficulté de déterminer quoi construire et comment le construire, en considérant seulement les exigences du système et des composants réutilisables, donc la question qui en découle est la suivante: comment spécifier une architecture SBC qui satisfait toutes les exigences du système? Nous proposons une approche de vérification formelle incrémentale basée sur des modèles SysML et des automates d'interface pour guider, par les exigences, le concepteur SBC afin de définir une architecture de système cohérente, qui satisfait toutes les exigences SysML proposées. Dans cette approche nous exploitons le model-checker SPIN et la LTL pour spécifier et vérifier les exigences.Mots clés: {Modélisation, Spécifications SysML, Architecture SBC, Raffinement, Compatibilité, Exigences, Propriétés LTL, Promela/SPIN, Ptolemy, MIO Workbench} / Formal and Incremental Verification of SysML Specifications for the Design of Component-Based SystemsThe work presented in this thesis is a contribution to the specification and verification of Component-Based Systems (CBS) modeled in SysML. CBS are widely used on the industrial field, and they are built by assembling various reusable components, allowing developing complex systems at lower cost.Despite the success of the use of CBS, their design is an increasingly complex step that requires the implementation of more rigorous approaches.To ease the communication between the various stakeholders in a CBS development project, one of the widely used modeling languages is SysML, which besides allowing modeling of structure and behavior, it has capabilities to model requirements. It offers a standard for modeling, specifying and documenting systems, wherein it is possible to develop a system, starting from an abstract level, to more detailed levels that may lead to an implementation.In this context, we have dealt mainly two issues. The first one concerns the development by refinement of a CBS, which is described only by its SysML interfaces and behavior protocols. Our contribution allows the designer of CBS to formally ensure that a composition of a set of elementary and reusable components refines an abstract specification of a CBS. In this contribution, we use the tools: Ptolemy for the verification of compatibility of the assembled components and MIO Workbench for refinement verification.The second one concerns the difficulty to decide what to build and how to build it, considering only system requirements and reusable components. Therefore, the question that arises is: how to specify a CBS architecture, which satisfies all system requirements? We propose a formal and incremental verification approach based on SysML models and interface automata to guide, by the requirements, the CBS designer to define a coherent system architecture that satisfies all proposed SysML requirements. In this approach we use the SPIN model-checker and LTL properties to specify and verify requirements.Keywords: {Modeling, SysML specifications, CBS architecture, Refinement, Compatibility, Requirements, LTL properties, Promela/SPIN, Ptolemy, MIO Workbench}