Software Product Line Engineering (SPLE) has been proven to reduce development and maintenance costs, improving the time-to-market, and increasing the quality of product variants developed from a product family via systematic reuse of its core assets. SPLE has been successfully used in the development of safety-critical systems, especially in automotive and aerospace domains. Safety-critical systems have to be developed according to safety standards, which demands safety analysis, Fault Tree Analysis (FTA), and assurance cases safety engineering artefacts. However, performing safety analysis, FTA, and assurance case construction activities from scratch and manually for each product variant is time-consuming and error-prone, whereas variability in safety engineering artefacts can be automatically managed with the support of variant management techniques. As safety is context-dependent, context and design variation directly impact in the safety properties changing hazards, their causes, the risks posed by these hazards to system safety, risk mitigation measures, and FTA results. Therefore, managing variability in safety artefacts from different levels of abstraction increases the complexity of the variability model, even with the support of variant management techniques. To achieve an effective balance between benefits and complexity in adopting an SPLE approach for safety-critical systems it is necessary to distinguish between reusable safety artefacts, whose variability should be managed, and those that should be generated from the reused safety artefacts. On the other hand, both industry and safety standards have recognized the use of model-based techniques to support safety analysis and assurance cases. Compositional safety analysis, design optimization, and model-based assurance cases are examples of techniques that have been used to support the generation of safety artefacts required to achieve safety certification. This thesis aims to propose a model-based approach that integrates model-based development, compositional safety analysis, and variant management techniques to support the systematic reuse and generation of safety artefacts in safety-critical software product line engineering. The approach contributes to reduce the effort and costs of performing safety analysis and assessment for a particular product variant, since such analysis is performed from the reused safety artefacts. Thus, variant-specific fault trees, Failure Modes and Effects Analysis (FMEA), and assurance case artefacts required to achieve safety certification can be automatically generated with the support the model-based safety analysis and assurance case construction techniques. / Engenharia de Linha de Produtos de Software (ELPS) contribui para a redução dos custos de desenvolvimento e de manutenção, a melhoria do time-to-market, e o aumento da qualidade de produtos desenvolvidos a partir de uma família de produtos por meio do reuso sistemático dos ativos principais da linha de produtos. A ELPS vem sendo utilizada com sucesso no desenvolvimento de sistemas embarcados críticos, especificamente nos domínios de sistemas automotivos e aeroespaciais. Sistemas embarcados críticos devem ser desenvolvidos de acordo com os requisitos definidos em padrões de segurança, que demandam a produção de artefatos de análise de segurança, árvores de falhas e casos de segurança. Entretanto, a realização de atividades de análise de segurança, análise de árvores de falhas e construção de casos de segurança de forma manual para cada produto de uma linha de produtos é uma tarefa demorada e propensa a erros. O gerenciamento de variabilidade em artefatos de análise de segurança pode ser automatizado com o apoio de técnicas de gerenciamento de variabilidades. Em virtude de safety ser uma propriedade dependente de contexto, a variabilidade no projeto e contexto inerente uma linha de produtos software impacta na definição de propriedades de segurança do sistema, modificando as ameaças à segurança do sistema, suas causas e riscos, medidas de mitigação aplicáveis, e resultados de análise de árvore de falhas. Dessa forma, gerenciar variabilidades em artefatos relacionados à safety em diferentes níveis de abstração aumenta a complexidade do modelo de variabilidade mesmo com o apoio de técnicas de gerenciamento de variabilidades. Para alcançar o equilíbrio eficaz entre os benefícios e a complexidade da adoção de uma abordagem de ELPS para o desenvolvimento de sistemas embarcados críticos é necessário fazer a distinção entre artefatos de safety reusáveis, em que a variabilidade deve ser gerenciada, e artefatos de safety que devem ser gerados a partir de artefatos reusáveis. Por outro lado, tanto a indústria quanto os padrões de segurança têm reconhecido o uso de técnicas dirigidas a modelos para apoiar a análise segurança e a construção de casos de segurança. Técnicas de análise de segurança composicional e otimização de projeto, e de construção de casos de segurança dirigido a modelos vêm sendo utilizadas para apoiar a geração de artefatos de safety requeridos para certificação. O objetivo desta tese é a proposta de uma abordagem dirigida a modelos que integra técnicas de desenvolvimento dirigido a modelos, análise de segurança composicional e otimização de projeto, e construção de casos de segurança dirigido a modelos para apoiar o reuso sistemático e a geração de artefatos de safety em engenharia de linhas de produtos de sistemas embarcados críticos. A abordagem proposta reduz o esforço e os custos de análise e avaliação de segurança para produtos de uma linha de produtos, uma vez que tal análise é realizada a partir de artefatos de safety reusados. Assim, artefatos como análises de árvores de falhas e de modos de falha e efeitos, e casos de segurança requeridos para certificação podem ser gerados automaticamente com o apoio de técnicas dirigidas a modelos.

Where do companies begin their efforts when trying to improve information management in product development? In large companies involving many people, multiple processes and highly technological products several factors have an impact on efficiency. Interdisciplinary integration and structured information are two overall proposed key factors that have been identified as important to obtain efficient information management. Measurement of satisfaction level among information systems users is proposed as an angle of approach to identify key improvement areas from an operative perspective that are argued to be strategic for management to address. However, the need for adjustments to contextual prerequisites and a changing environment makes evaluation necessary prior to measurement. An evaluation framework is proposed to identify metrics that are tailored and kept in line with business and development strategies to ensure their relevancy. This research has aimed at taking a holistic approach to information management in complex product development. The research focus has been on the integration between engineering disciplines where software and electrical R&D departments at automotive companies have been the main source of the analysis material. Integrated information management entails support for activities within the engineering domain. Several strategies are discussed to manage trade-offs in organizations in order to succeed with integrated information management. A needs-based balance is one important approach proposed to resolve changing and conflicting needs. Furthermore, it is argued that operative and strategic goals should be allowed to co-exist. Providing the right infrastructure to support designers in their everyday work does not necessarily mean additional functionality to existing information systems or automated work activities by improved document templates. Rather, it is suggested that a shift in focus (from addressing detailed requirements management to reflecting on interrelationships between information objects and system inter-dependencies) would be a strong mechanism to succeed with information management. The transition into model-based development is argued to be a much needed change for organizations to obtain integrated information management, since a model-based approach is considered an important basis for structured information. Anticipated benefits with integrated information management are increased information availability, reduced information overflow, and enhanced communication and understanding of critical system dependencies / QC 20100730

Made available in DSpace on 2014-12-17T15:47:02Z (GMT). No. of bitstreams: 1 MacilonACN_TESE.pdf: 3979579 bytes, checksum: 8cbe12645bc4c083bd9eabb00da34227 (MD5) Previous issue date: 2013-05-10 / The development of interactive systems involves several professionals and the integration between them normally uses common artifacts, such as models, that drive the development process. In the model-driven development approach, the interaction model is an artifact that includes the most of the aspects related to what and how the user can do while he/she interacting with the system. Furthermore, the interactive model may be used to identify usability problems at design time. Therefore, the central problematic addressed by this thesis is twofold. In the first place, the interaction modeling, in a perspective that helps the designer to explicit to developer, who will implement the interface, the aspcts related to the interaction process. In the second place, the anticipated identification of usability problems, that aims to reduce the application final costs. To achieve these goals, this work presents (i) the ALaDIM language, that aims to help the designer on the conception, representation and validation of his interactive message models; (ii) the ALaDIM editor, which was built using the EMF (Eclipse Modeling Framework) and its standardized technologies by OMG (Object Management Group); and (iii) the ALaDIM inspection method, which allows the anticipated identification of usability problems using ALaDIM models. ALaDIM language and editor were respectively specified and implemented using the OMG standards and they can be used in MDA (Model Driven Architecture) activities. Beyond that, we evaluated both ALaDIM language and editor using a CDN (Cognitive Dimensions of Notations) analysis. Finally, this work reports an experiment that validated the ALaDIM inspection method / No desenvolvimento de um sistema interativo, est?o envolvidos diversos profissionais e a integra??o entre eles se d?, principalmente, atrav?s do compartilhamento de artefatos comuns, como modelos, por exemplo. O uso de modelos possibilita uma abordagem de desenvolvimento na qual os modelos s?o usados por designers e desenvolvedores. Na abordagem baseada em modelos, o modelo de intera??o ? um artefato que cobre a maioria dos aspectos relacionados ao o que e como o usu?rio pode fazer ao interagir com a aplica??o. Al?m disso, ele pode ser usado para a identifica??o de problemas de usabilidade durante o design e n?o apenas durante os testes de interface e aceita??o, o que reduz o impacto nos custos do processo de desenvolvimento. Nesse sentido, este trabalho endere?a duas quest?es. A primeira ? a modelagem da intera??o, sob uma perspectiva que auxilie o designer a explicitar para o desenvolvedor, que ir? codificar na interface, os aspectos relacionados ao processo interativo, especificamente o que e como . A segunda ? identifica??o antecipada de problemas de usabilidade, que visa contribuir, principalmente, com a redu??o dos custos de desenvolvimento. Para isso, este trabalho apresenta (i) a linguagem ALaDIM, para auxiliar o designer na concep??o, representa??o e valida??o do modelo de intera??o; (ii) o editor ALaDIM, que foi constru?do usando o EMF (Eclipse Modeling Framework) e suas tecnologias padronizadas pelo OMG (Object Management Group); e (iii) o m?todo de inspe??o ALaDIM, que permite a identifica??o antecipada de problemas de usabilidade em modelos ALaDIM. A linguagem e o editor ALaDIM foram, respectivamente, especificada e implementado, usando padr?es do OMG e podem ser empregados em atividades MDA (Model Driven Architecture). Al?m disso, foram avaliados a linguagem e o editor ALaDIM, atrav?s da an?lise da dimens?es cognitivas de ambos, usando o CDN (Cognitive Dimensions of Notations). Finalmente, este trabalho relata um experimento para valida??o do m?todo de inspe??o

Au cours des dernières années, l'utilisation d’appareils embarqués a augmenté rapidement en raison de la commodité qu'ils offrent dans la vie quotidienne. Les appareils embarqués se caractérisent par leur petite taille, leur portabilité ainsi que leur capacité d'échanger des données avec d'autres appareils grâce à leur service de communication réseau. L'analyse du comportement et les interactions entre ces appareils a abouti dans l'établissement d’un nouveau type de système, appelé systèmes embarqués en réseau.En tant que la popularité actuelle des systèmes embarqués en réseau grandissent, il y a une tendance de relever leurs défis de conception existants afin de développer d'applications fonctionnelles. Ces défis concernent l'utilisation de leurs ressources matérielles limitées (p.ex. la mémoire du processeur, l'unité d'alimentation) et l'hétérogénéité du système en termes de logiciel, de matériel et aussi des mécanismes d'interaction entre les appareils. A cet effet, dans cette thèse nous présentons une approche rigoureuse considérant tous les défis grâce à un flot de conception basée sur techniques de modélisation. Le flot utilise le formalisme BIP pour la construction hiérarchique de systèmes autour de composants et il est facilement utilisé, car chaque étape est entièrement automatisée par des outils et méthodes développés. En plus, ce flot perme la simulation des systèmes à chaque étape de développement, la vérification par l'exploration de l'espace de conception, la génération de code et la calibration des modèles développés, afin de présenter fidèlement le système réel. Les modèles calibrés peuvent analyser la performance de system et aussi valider des exigences sur le system. Finalement, les résultats d'analyse de performance peuvent apporter des améliorations sur la conception de système cible.Notre approche est présenté sur plusieurs bien connus domaines applicatifs des systèmes embarqués en réseau, comme les systèmes automobiles, les systèmes de l'automation industrielle, les systèmes de réseaux de capteurs sans fil (WSN systèmes) et les systèmes pour l'internet des objets (IoT systèmes). Chaque domaine inclut différentes caractéristiques et technologies, mais dispose également différent défis. Ces défis sont considérés par les outils développés pour chaque domaine, qui sont validées contre les outils existantes, comme MATLAB/Simulink, RTaW-Sim, OPNET Modeler et Cooja. La validation se fait grâce à les cas d’études sur les applications industrielles ou les benchmark réalistes des systèmes embarqués en réseau. Nos expérimentations illustrent le soutien d'une meilleure analyse par les outils développés en fournissant d'abord résultats similaires pendant la simulation et en plus les capacités de génération automatique de code et la vérification des exigences. / Over the latest years the use of embedded devices has expanded rapidly due to the convenience they offer in daily life. Embedded devices are characterized by their tiny size, their portability as well as their ability to exchange data with other devices through a dedicated network unit. The analysis of the behavior and interactions between such devices lead to the emergence of a new system type, called networked embedded systems.As the current popularity of networked embedded systems grows, there is a trend for addressing their existing design challenges in the development of functional applications. These challenges relate to the use of their limited hardware resources (e.g. processor memory, power unit) and the system heterogeneity in terms of software, hardware as well as communication mechanisms between the embedded devices. To this end, in this thesis we present a rigorous approach considering all the design challenges through a model-based design flow. The flow uses BIP as an underlying framework for the hierarchical construction of component-based systems and it is easily employed, as each step is fully supported by developed tools and methods. Its benefits include early-stage simulation and testing, verification of functional correctness, generation of deployable code and collection of performance data from real executions, in order to calibrate the developed models. Calibrated models represent faithfully the real system and can analyze system performance as well as evaluate accurately system requirements. Additionally, performance analysis results may provide design enhancements in the target system.Our approach is demonstrated in several well-known application domains of networked embedded systems, namely the automotive, industrial automation, Wireless Sensor Network (WSN) and Internet of Things (IoT) systems. Each domain includes different characteristics and technologies, but also features different challenges. These challenges are considered by developed tools for each domain, which are validated against existing domain-specific, such as MATLAB/Simulink, RTaW-Sim, OPNET Modeler and Cooja. The validation is facilitated through case-studies in industrial or benchmark networked embedded systems. Our experiments illustrate the support of a better fine-grained analysis from the developed tools by initially providing similar simulation results and additionally offering capabilities for automated code generation as well as requirement verification.

As autonomous driving is rapidly becoming the next major challenge in the auto- motive industry, the problem of Simultaneous Localization And Mapping (SLAM) has never been more relevant than it is today. This thesis presents the idea of examining SLAM algorithms by implementing such an algorithm on a radio con- trolled car which has been fitted with sensors and microcontrollers. The software architecture of this small-scale vehicle is based on the Robot Operating System (ROS), an open-source framework designed to be used in robotic applications. This thesis covers Extended Kalman Filter (EKF)-based SLAM, FastSLAM, and GraphSLAM, examining these algorithms in both theoretical investigations, simulations, and real-world experiments. The method used in this thesis is model- based development, meaning that a model of the vehicle is first implemented in order to be able to perform simulations using each algorithm. A decision of which algorithm to be implemented on the physical vehicle is then made backed up by these simulation results, as well as a theoretical investigation of each algorithm. This thesis has resulted in a dynamic model of a small-scale vehicle which can be used for simulation of any ROS-compliant SLAM-algorithm, and this model has been simulated extensively in order to provide empirical evidence to define which SLAM algorithm is most suitable for this application. Out of the algo- rithms examined, FastSLAM was proven to the best candidate, and was in the final stage, through usage of the ROS package gMapping, successfully imple- mented on the small-scale vehicle.

Made available in DSpace on 2016-06-02T19:06:07Z (GMT). No. of bitstreams: 1 5452.pdf: 2351043 bytes, checksum: 0d55a4fbf3ab7f02e097b7df0101db3c (MD5) Previous issue date: 2011-12-13 / Financiadora de Estudos e Projetos / Embedded systems (ES) has become more important to everyday life due to technology advance and increasing application field. Engineers start ES development using tools like Matlab/Simulink. Usually, Simulink models are low level abstraction models following an ad-hoc design, which difficult the model comprehension. Hence, new trends start to apply software engineering to support ES design. Goal: This work was developed in a research group that is defining a development process to support ES development from initial phases to Simulink models implementation. Particularly, this works goal is to explore UML Statchart technique to depict Simulink models in a high level abstraction view, and become the group s desired component part of the process. Method: The investigation process was conducted in three actions exploring UML Statchart based in the Research Action methodology: (i) a reengineering activity starting from Simulink model; (ii) a forward engineering starting from a requirement document; and (iii) a survey investigating the use of UML Statechart by ES developers. Outcomes: The first and second action showed that UML Statechart is an appropriated technique to depict the application behavior, contributing to implement Simulink models. It also organizes Simulink models and facilitates the system comprehension as a whole. Conclusion: Due to the conducted actions outcomes, UML Statechart can be considered as a candidate to compose one of the artifacts to be implemented during the process that is being defined by the research group. However, this work conducted investigations are limited to two system applications, needing to accomplish more complement studies, we can say that Simulink models implemented with support of UML Statechart, are better structured and more comprehensive. This features an increasing quality in ES design. / Os sistemas embarcados (SE) têm se tornado cada vez mais presentes na vida das pessoas em decorrência dos avanços tecnológicos e do aumento na diversidade em suas áreas de aplicação. Em geral, os desenvolvedores desse tipo de sistema iniciam o desenvolvimento com o uso de ferramentas do tipo Matlab/Simulink, elaborando modelos em um nível baixo de abstração, que são construídos de forma desorganizada, o que dificulta o entendimento da aplicação. Em decorrência disso, observam-se iniciativas de uso da engenharia de software nesse tipo de sistema. Objetivo: O grupo de pesquisa no qual este trabalho foi desenvolvido está definindo um processo para o desenvolvimento de SEs que dê suporte das fases iniciais até a construção dos modelos Simulink. Em particular, este trabalho tem o objetivo de explorar o uso da UML Statechart para retratar o modelo Simulink em um nível mais alto de abstração, tornando-se então um dos componentes do processo almejado pelo grupo. Método: Para fazer essa investigação, utilizou-se a metodologia Pesquisa-Ação e três ações foram conduzidas, explorando-se a UML Statechart em: (i) uma atividade de reengenharia, partindo do Simulink e reestruturando-o; (ii) em uma atividade de engenharia avante, partindo de um documento de requisitos; e (iii) em um survey, caracterizando o uso da UMS Statechart por desenvolvedores de SEs. Resultados: Nas duas primeiras ações, a UML Statechart se mostrou apropriada para representar o comportamento da aplicação, de forma a contribuir na construção do modelo Simulink, facilitando a compreensão do sistema como um todo e permitindo a elaboração de um Simulink mais organizado. Conclusões: Os resultados obtidos nas ações permitem considerar que a UML Statechart é uma forte candidata para compor um dos artefatos a serem construídos durante o processo que está sendo definido pelo grupo de pesquisa. Embora as investigações conduzidas neste trabalho estejam limitadas a duas aplicações, requerendo que outros estudos sejam realizados, pode-se dizer que os modelos Simulink construídos com o apoio do modelo UML Statechart são mais estruturados e mais compreensíveis. Isso caracteriza uma melhora de qualidade no desenvolvimento de SEs.

Software Product Line Engineering (SPLE) has been proven to reduce development and maintenance costs, improving the time-to-market, and increasing the quality of product variants developed from a product family via systematic reuse of its core assets. SPLE has been successfully used in the development of safety-critical systems, especially in automotive and aerospace domains. Safety-critical systems have to be developed according to safety standards, which demands safety analysis, Fault Tree Analysis (FTA), and assurance cases safety engineering artefacts. However, performing safety analysis, FTA, and assurance case construction activities from scratch and manually for each product variant is time-consuming and error-prone, whereas variability in safety engineering artefacts can be automatically managed with the support of variant management techniques. As safety is context-dependent, context and design variation directly impact in the safety properties changing hazards, their causes, the risks posed by these hazards to system safety, risk mitigation measures, and FTA results. Therefore, managing variability in safety artefacts from different levels of abstraction increases the complexity of the variability model, even with the support of variant management techniques. To achieve an effective balance between benefits and complexity in adopting an SPLE approach for safety-critical systems it is necessary to distinguish between reusable safety artefacts, whose variability should be managed, and those that should be generated from the reused safety artefacts. On the other hand, both industry and safety standards have recognized the use of model-based techniques to support safety analysis and assurance cases. Compositional safety analysis, design optimization, and model-based assurance cases are examples of techniques that have been used to support the generation of safety artefacts required to achieve safety certification. This thesis aims to propose a model-based approach that integrates model-based development, compositional safety analysis, and variant management techniques to support the systematic reuse and generation of safety artefacts in safety-critical software product line engineering. The approach contributes to reduce the effort and costs of performing safety analysis and assessment for a particular product variant, since such analysis is performed from the reused safety artefacts. Thus, variant-specific fault trees, Failure Modes and Effects Analysis (FMEA), and assurance case artefacts required to achieve safety certification can be automatically generated with the support the model-based safety analysis and assurance case construction techniques. / Engenharia de Linha de Produtos de Software (ELPS) contribui para a redução dos custos de desenvolvimento e de manutenção, a melhoria do time-to-market, e o aumento da qualidade de produtos desenvolvidos a partir de uma família de produtos por meio do reuso sistemático dos ativos principais da linha de produtos. A ELPS vem sendo utilizada com sucesso no desenvolvimento de sistemas embarcados críticos, especificamente nos domínios de sistemas automotivos e aeroespaciais. Sistemas embarcados críticos devem ser desenvolvidos de acordo com os requisitos definidos em padrões de segurança, que demandam a produção de artefatos de análise de segurança, árvores de falhas e casos de segurança. Entretanto, a realização de atividades de análise de segurança, análise de árvores de falhas e construção de casos de segurança de forma manual para cada produto de uma linha de produtos é uma tarefa demorada e propensa a erros. O gerenciamento de variabilidade em artefatos de análise de segurança pode ser automatizado com o apoio de técnicas de gerenciamento de variabilidades. Em virtude de safety ser uma propriedade dependente de contexto, a variabilidade no projeto e contexto inerente uma linha de produtos software impacta na definição de propriedades de segurança do sistema, modificando as ameaças à segurança do sistema, suas causas e riscos, medidas de mitigação aplicáveis, e resultados de análise de árvore de falhas. Dessa forma, gerenciar variabilidades em artefatos relacionados à safety em diferentes níveis de abstração aumenta a complexidade do modelo de variabilidade mesmo com o apoio de técnicas de gerenciamento de variabilidades. Para alcançar o equilíbrio eficaz entre os benefícios e a complexidade da adoção de uma abordagem de ELPS para o desenvolvimento de sistemas embarcados críticos é necessário fazer a distinção entre artefatos de safety reusáveis, em que a variabilidade deve ser gerenciada, e artefatos de safety que devem ser gerados a partir de artefatos reusáveis. Por outro lado, tanto a indústria quanto os padrões de segurança têm reconhecido o uso de técnicas dirigidas a modelos para apoiar a análise segurança e a construção de casos de segurança. Técnicas de análise de segurança composicional e otimização de projeto, e de construção de casos de segurança dirigido a modelos vêm sendo utilizadas para apoiar a geração de artefatos de safety requeridos para certificação. O objetivo desta tese é a proposta de uma abordagem dirigida a modelos que integra técnicas de desenvolvimento dirigido a modelos, análise de segurança composicional e otimização de projeto, e construção de casos de segurança dirigido a modelos para apoiar o reuso sistemático e a geração de artefatos de safety em engenharia de linhas de produtos de sistemas embarcados críticos. A abordagem proposta reduz o esforço e os custos de análise e avaliação de segurança para produtos de uma linha de produtos, uma vez que tal análise é realizada a partir de artefatos de safety reusados. Assim, artefatos como análises de árvores de falhas e de modos de falha e efeitos, e casos de segurança requeridos para certificação podem ser gerados automaticamente com o apoio de técnicas dirigidas a modelos.

The number and complexity of the systems realizing the functionality of the machines in the automotive domain are growing. In this arises the need for a systematic way to manage their development. As the technologies advance, the vehicles introduce an increasing range of capabilities. However, they have similar functions, which have the potential to be reused. One of the widely used approaches that manages the commonality and variability of the development artifacts in a systematic manner is Product Line Engineering (PLE). Consequently, PLE reduces the time to market and the development cost. The machines, realized in the automotive domain, interact with their operators and the surrounding environment. Possible malfunctions of the machines may introduce a risk of accidents with fatal consequences. Therefore, the products should be analyzed, developed and managed in a safe manner and certified according to different relevant safety standards like ISO 15998, ISO 61508 and ISO 26262. There is a diversity of functions in a Product Line (PL). Some of them are mandatory for all machines and others are optional for some models. This gives the opportunity to combine the functions in multiple configurations. However, not all combinations are possible due to dependencies among the functions. Furthermore, the configurations should be valid from a safety perspective, and the developed products should satisfy the requirements identified during the safety analysis. The above mentioned factors emphasize the need for explicit representation of the systems' characteristics, such as commonality and variability, functional dependencies and quality attributes. The purpose of the current work is to find an efficient way to satisfy this need. The scope of our research is limited to the automotive domain. In order to gain familiarity with the state of practice, we collaborated with Volvo Construction Equipment (Volvo CE) as an industrial partner. In particular, we: conducted an informal interview study with the practitioners, analyzed the requirements management tool used in Volvo CE and studied products typical for the domain in detail, examined the deliverables defined in the related domain specific safety standards. We gained knowledge on how variability is managed in an industrial context today, which safety aspects need to be considered and how functional safety artifacts are managed with regards to variability. We synthesized the characteristics that are explicitly represented during the development and safety certification of the products in a safety-critical product line. We identified the challenges that the practitioners meet today and the areas that need to be improved. As a result, we formulated evaluation criteria for search and assessment of possible solutions. Subsequently we searched in the literature for different modeling techniques, that are able to respond to the industrial needs, and found the following to be relevant in our context: Feature modeling techniques consider the different variability types and dependencies among the features. Model-based development techniques can represent different views of the system on each level of the development process. Orthogonal modeling techniques extract the variability and dependencies in a different view. Furthermore, we evaluated the methods found during the literature study, based on the proposed criteria. We concluded that the examined techniques alone cannot represent all characteristics needed to support the development of a safety-critical product line, especially the impact of the variability on the safety and vice versa. However, each of them focuses on the presentation of certain aspect of the product line, which can help in building a more complete representation. Thus we focused on the approaches that may be extended and integrated into a complete solution. As a result, we propose a model and graphical notation for variability management in safety-critical product lines, which takes the identified industrial needs into account. The concept is depicted graphically by several model-based diagrams, which represent the different aspects of the product line, on each development level. Special attention is paid to the representation of the safety and variability aspects of the systems. The method is exemplified on an industrial example, in order to show how it achieves the defined goals.

Ein geringer Treibstoffverbrauch ist aufgrund von ökologischen und ökonomischen Zielen für die zivile Luftfahrt von großer Bedeutung. Daher werden seit Jahrzehnten konventionell hydraulisch oder pneumatisch betriebene Flugzeugsysteme durch elektrisch betriebene Systeme ersetzt. Dieser Trend wird auch als „More Electric Aircraft (MEA)“ bezeichnet. In bisherigen Studien waren MEA-Architekturen zwar effizienter, jedoch deutlich schwerer als die konventionellen Architekturen. Basierend auf ökonomischen Modellen wird in der vorliegenden Arbeit die modellbasierte Entwicklung eines intelligenten Energiemanagements für Flugzeug-Energiesysteme demonstriert. Das Energiemanagement ermöglicht eine deutliche Reduktion der Systemmasse, verbessert die Energieeffizienz und kann damit den Treibstoffverbrauch eines MEA beträchtlich reduzieren. Insbesondere durch die integrierte und frühzeitige Entwicklung des Energiemanagements mit dem elektrischen System in der Modellbeschreibungssprache Modelica lassen sich die Systemkomponenten mit realistischen Lastprofilen dimensionieren und dadurch die Systemmasse reduzieren. Anhand eines elektrischen Referenzsystems wird das Optimierungspotenzial des Energiemanagements bezüglich Massenreduktion und Energieeffizienzsteigerung quantifiziert und am Systemmodell validiert. Es ergibt sich für das Systemmodell eine Reduktion der Systemmasse um 32 % sowie eine leichte Verbesserung der Energieeffizienz. Durch die multiphysikalische Implementierung des Energiemanagements lässt sich dieses auch für das thermische Management im Flugzeug verwenden. Hierbei kann eine deutliche Verbesserung der Energieeffizienz für die Bereitstellung von Kühlleistung erzielt werden. Aufgrund der erreichten Vorteile sollte ein Energiemanagement bei der Entwicklung zukünftiger Flugzeugenergiesysteme in Betracht gezogen werden. Insbesondere beim MEA existiert ein großes Optimierungspotenzial durch das Energiemanagement. Die Ausführungen in der vorliegenden Arbeit sollen als Motivation für die Flugzeugindustrie dienen, mit realistischen Lastprofilen zu dimensionieren und die modellbasierte und integrierte Entwicklung eines Energiemanagements mit den Energiesystemen bereits in frühen Entwicklungsphasen durchzuführen. / Low fuel consumption is a major concern in civil aerospace due to environmental and economic objectives. Hence, conventional hydraulically or pneumatically driven aircraft systems have been replaced by electrically driven systems for decades. This trend is also known as More Electric Aircraft (MEA). In former studies, MEA architectures were more efficient, but much heavier than their conventional counterparts. The present work demonstrates the model-based development of intelligent energy management algorithms for aircraft energy systems based on economic models. This energy management facilitates a significant reduction of system mass, improves energy efficiency and can hence reduce fuel consumption of MEA considerably. In particular, the integrated development of an energy management along with the electrical system in the Modelica modelling language enables sizing of system components with realistic load profiles. Hence, this reduces the system mass. The optimization potential of the energy management is quantified and validated by means of an electrical reference system model. Applying the energy management, the mass of this system model can be reduced by 32 % and the energy efficiency can be improved slightly. Due to the multi-physical modelling of the energy management, it can also be applied to thermal management of aircraft systems. Thus, the energy efficiency of the cooling system can be improved significantly. As a result of the demonstrated benefits, an energy management should be considered for future development of aircraft energy systems. Especially for MEA, there is tremendous optimization potential for the energy management. Hence, the present work shall motivate aircraft industry to size aircraft systems with realistic load profiles and perform a model-based and integrated development of the energy management along with the electrical system in early phases of the system design process.

ROS2 is an increasingly popular middleware framework for developing robotic applications. A ROS2 applicationbasically is composed of nodes that run concurrently and can be deployed distributedly. ROS2 nodes communicatewith each other through asynchronous interfaces; they reside in memory and wait to respond events that circulatearound the system during the interactions between the robot(s) and the environment. Rebeca is an actor-basedlanguage for modelling asynchronous, concurrent applications. Timed Rebeca added timing features to Rebeca todeal with timing requirements of real-time systems. The similarities in the concurrency and message-basedasynchronous interactions ofreactive nodes justify the relevance of using Timed Rebeca to assist the developmentand verification of ROS2 applications. Model-based development and model checking allow quicker prototypingand earlier detection ofsystem errors without the requirement of developing the entire real system. However, thereare challenges in bridging the gaps between continuous behaviours in a real robotic system and discrete behavioursin a model, between complex computations in a robotic system and the inequivalent programming facilities in amodelling language. There have been previous attempts in mapping Rebeca to ROS, however they could not beput into practice due to over-simplifications or improper modelling approaches. This thesis addresses the problemfrom a more systematic perspective and has been successful in modelling a realistic multiple autonomous mobilerobots system, creating corresponding ROS2 demonstration code, showing the synchronization between the modeland the program to prove the values of the model in driving development and automatic verification of correctnessproperties (freedom ofdeadlocks, collisions, and congestions). Stability of model checking results confirms designproblems that are not always detected by simulation. The modelling principles, modelling and implementingtechniques that are invented and summarized in this work can be reused for many other cases.