In order to improve the comfort of power wheelchair users, it is proposed in this dissertation the implementation of a position and orientation control system which allow the users to travel the desired trajectories safely, without the need for constant interaction with the device command system. To reach this objective, it is proposed a methodology for the implementation of a control system, able to drive the vehicle from an initial position to the desired one or make it follow a specified trajectory, from commands received in the system. The proposed control system is based on a cascade control law, composed by a nonlinear pose controller and a velocity tracking controller. Two velocity control strategies are proposed. The first one uses a velocity controller composed of two joint-independent Proportional-Integral controllers while the second one uses a velocity controller based on the dynamic model, which is linearized by a state-feedback. The methods are implemented using the ros_control package, provided by the framework Robot Operating System (ROS). The evaluation of the proposed methods is done with a differential-drive mobile robot, which has the same kinematic configuration as the majority of commercial power wheelchairs. The results of dynamic-model parameter identification, as well as the convergence of the controlled variables by using the proposed control methods, are presented. The results demonstrate that the methods achieve the proposed control objectives.

A sociedade está cada vez mais dependente de sistemas embarcados, sendo que na grande maioria das vezes eles operam de maneira invisível aos seus usuários. Essa dependência torna esses usuários vulneráveis a riscos, devido às falhas que podem ocorrer. Essas falhas podem provocar perdas de vidas ou sérios danos materiais e financeiros. Devido a estes fatos, a qualidade destes produtos torna-se um ponto essencial para se ter um sistema estável, livre de erros e com todas as suas funcionalidades sendo executadas. De encontro a isso, a etapa de teste apresenta-se como indispensável e de relevada importância para a obtenção de um produto com uma boa qualidade. Devido ao alto custo de produção e energia gasto com testes, surge a necessidade de novos estudos, sobre diversificados métodos, para se testar um sistema embarcado. Neste contexto, este trabalho tem como objetivo apresentar os estudos iniciais do teste de um Sistema Operacional Embarcado (SOE), através de um estudo de caso focado na rotina de tratamento de exceção do eCos (Embedded Configurable Operating System), pois ela apresenta uma forte interação entre software e hardware, sendo que esta interação é um dos principais desafios encontrados no teste de um software embarcado. Com isso, este trabalho pretende dar o passo inicial para pesquisas relacionadas aos testes de um Sistema Operacional Embarcado. Após a análise dos experimentos, pôde-se notar que a principal característica do Sistema Operacional Embarcado eCos, a configurabilidade, é um ponto de dificuldade extra para a realização dos testes, pois exige um estudo detalhado do código do SOE, o qual é totalmente genérico, antes do planejamento dos testes, podendo ser gasto muito tempo nessa atividade. Outro ponto é que o teste torna-se totalmente dependente do hardware. Entretanto, os resultados experimentais apresentados para o estudo de caso do presente trabalho foram satisfatórios. / Society is increasingly dependent on embedded systems, which in most cases operate in an invisible manner to its users. This dependence makes the user vulnerable to risks due to failures that may occur. These failures can cause loss of lives or serious property and financial damage. Because of these facts, the quality of these products becomes a key point to have a stable system, free of errors and with all the features running. This testing is of essential importance to obtain a product with good quality. Due to the high cost of production and energy spent on tests, there is a need for further studies on different methods, to test an embedded system. In this context, this work aims at presenting the initial studies as the testing of the Embedded Operating System. The case study was focused on the exception handling routine of the eCos (Embedded Configurable Operating System), because it has a strong interaction between software and hardware, and this interaction is one of the main challenges encountered in testing embedded software. Therefore, this work aims at taking the first steps towards research related to testing an Embedded Operating System. After analyzing the experiments, it was noted that the main feature of the Embedded Operating System, eCos, the configurability, is an extra point of difficulty for the tests. It requires a detailed study of the code eCos, which is completely general, before the planning of tests, and could be spent much time in this activity. Another point is that the test becomes totally dependent on hardware. However, the experimental results presented for the case study of this study showed satisfactory.

In order to improve the comfort of power wheelchair users, it is proposed in this dissertation the implementation of a position and orientation control system which allow the users to travel the desired trajectories safely, without the need for constant interaction with the device command system. To reach this objective, it is proposed a methodology for the implementation of a control system, able to drive the vehicle from an initial position to the desired one or make it follow a specified trajectory, from commands received in the system. The proposed control system is based on a cascade control law, composed by a nonlinear pose controller and a velocity tracking controller. Two velocity control strategies are proposed. The first one uses a velocity controller composed of two joint-independent Proportional-Integral controllers while the second one uses a velocity controller based on the dynamic model, which is linearized by a state-feedback. The methods are implemented using the ros_control package, provided by the framework Robot Operating System (ROS). The evaluation of the proposed methods is done with a differential-drive mobile robot, which has the same kinematic configuration as the majority of commercial power wheelchairs. The results of dynamic-model parameter identification, as well as the convergence of the controlled variables by using the proposed control methods, are presented. The results demonstrate that the methods achieve the proposed control objectives.

A sociedade está cada vez mais dependente de sistemas embarcados, sendo que na grande maioria das vezes eles operam de maneira invisível aos seus usuários. Essa dependência torna esses usuários vulneráveis a riscos, devido às falhas que podem ocorrer. Essas falhas podem provocar perdas de vidas ou sérios danos materiais e financeiros. Devido a estes fatos, a qualidade destes produtos torna-se um ponto essencial para se ter um sistema estável, livre de erros e com todas as suas funcionalidades sendo executadas. De encontro a isso, a etapa de teste apresenta-se como indispensável e de relevada importância para a obtenção de um produto com uma boa qualidade. Devido ao alto custo de produção e energia gasto com testes, surge a necessidade de novos estudos, sobre diversificados métodos, para se testar um sistema embarcado. Neste contexto, este trabalho tem como objetivo apresentar os estudos iniciais do teste de um Sistema Operacional Embarcado (SOE), através de um estudo de caso focado na rotina de tratamento de exceção do eCos (Embedded Configurable Operating System), pois ela apresenta uma forte interação entre software e hardware, sendo que esta interação é um dos principais desafios encontrados no teste de um software embarcado. Com isso, este trabalho pretende dar o passo inicial para pesquisas relacionadas aos testes de um Sistema Operacional Embarcado. Após a análise dos experimentos, pôde-se notar que a principal característica do Sistema Operacional Embarcado eCos, a configurabilidade, é um ponto de dificuldade extra para a realização dos testes, pois exige um estudo detalhado do código do SOE, o qual é totalmente genérico, antes do planejamento dos testes, podendo ser gasto muito tempo nessa atividade. Outro ponto é que o teste torna-se totalmente dependente do hardware. Entretanto, os resultados experimentais apresentados para o estudo de caso do presente trabalho foram satisfatórios. / Society is increasingly dependent on embedded systems, which in most cases operate in an invisible manner to its users. This dependence makes the user vulnerable to risks due to failures that may occur. These failures can cause loss of lives or serious property and financial damage. Because of these facts, the quality of these products becomes a key point to have a stable system, free of errors and with all the features running. This testing is of essential importance to obtain a product with good quality. Due to the high cost of production and energy spent on tests, there is a need for further studies on different methods, to test an embedded system. In this context, this work aims at presenting the initial studies as the testing of the Embedded Operating System. The case study was focused on the exception handling routine of the eCos (Embedded Configurable Operating System), because it has a strong interaction between software and hardware, and this interaction is one of the main challenges encountered in testing embedded software. Therefore, this work aims at taking the first steps towards research related to testing an Embedded Operating System. After analyzing the experiments, it was noted that the main feature of the Embedded Operating System, eCos, the configurability, is an extra point of difficulty for the tests. It requires a detailed study of the code eCos, which is completely general, before the planning of tests, and could be spent much time in this activity. Another point is that the test becomes totally dependent on hardware. However, the experimental results presented for the case study of this study showed satisfactory.

Le système d'exploitation (OS) est un concept bien connu en informatique comme interface entre l'Homme et le matériel informatique (MacOS, Windows, IOS, Android, ...). Dans le but de développer la future génération de systèmes d'entreprise basés sur les principes de l'IoT et du Cyber-Physique, cette thèse propose de développer un système d'exploitation d'entreprise « System d’Exploitation des Entreprises » (EOS); Contrairement à ERP, qui est défini comme un programme qui permet à l'organisation au niveau opérationnel d'utiliser un système d'applications intégrées afin d'automatiser de nombreuses fonctions liées à la technologie et aux services, EOS servira d'interface entre les gestionnaires d'entreprise et les ressources d'entreprise pour le suivi en temps réel et le contrôle des opérations.Nous présenterons d'abord le contexte, les priorités, les défis et les résultats escomptés. Ensuite, un ensemble d'exigences et de fonctionnalités d'EOS est décrit. Après, un état de l’art existant sur les travaux pertinents est donné et mis en correspondance avec les exigences spécifiées liées à EOS. Par la suite, et en fonction des exigences et des résultats, les architectures conceptuelle, technique et d’implantation sont décrites, y compris tous les composants internes et externes. La dernière partie présenteront deux exemples dans les secteurs bancaire et manufacturier pour illustrer l'utilisation de l'EOS. / Operating System (OS) is a well-known concept in computer science as an interface between human and computer hardware (MacOS, Windows, IOS, Android,…). In the perspective of developing future generation of enterprise systems based on IoT and Cyber-Physical System principles, this doctorate research proposes to develop an Enterprise Operating System (EOS); Unlike ERP, which is defined as a platform that allows the organization at the operational level to use a system of integrated applications in order to automate many back office functions related to technology and services, EOS will act as an interface between enterprise business managers and enterprise resources for real time monitoring and control of enterprise operations.The thesis presents at first the context, priorities, challenges and expected results. Then a set of requirements and functionalities of EOS is described. After that, a survey on existing relevant works is given and mapped to the specified requirements related to EOS. Afterwards, and based on the requirements and state-of-the-art results, the EOS conceptual, technical and implementation architectures are outlined including all internal and external components. The last part draws two examples in the banking and manufacturing sectors to illustrate the use of the EOS.

A sociedade está cada vez mais dependente de sistemas embarcados, sendo que na grande maioria das vezes eles operam de maneira invisível aos seus usuários. Essa dependência torna esses usuários vulneráveis a riscos, devido às falhas que podem ocorrer. Essas falhas podem provocar perdas de vidas ou sérios danos materiais e financeiros. Devido a estes fatos, a qualidade destes produtos torna-se um ponto essencial para se ter um sistema estável, livre de erros e com todas as suas funcionalidades sendo executadas. De encontro a isso, a etapa de teste apresenta-se como indispensável e de relevada importância para a obtenção de um produto com uma boa qualidade. Devido ao alto custo de produção e energia gasto com testes, surge a necessidade de novos estudos, sobre diversificados métodos, para se testar um sistema embarcado. Neste contexto, este trabalho tem como objetivo apresentar os estudos iniciais do teste de um Sistema Operacional Embarcado (SOE), através de um estudo de caso focado na rotina de tratamento de exceção do eCos (Embedded Configurable Operating System), pois ela apresenta uma forte interação entre software e hardware, sendo que esta interação é um dos principais desafios encontrados no teste de um software embarcado. Com isso, este trabalho pretende dar o passo inicial para pesquisas relacionadas aos testes de um Sistema Operacional Embarcado. Após a análise dos experimentos, pôde-se notar que a principal característica do Sistema Operacional Embarcado eCos, a configurabilidade, é um ponto de dificuldade extra para a realização dos testes, pois exige um estudo detalhado do código do SOE, o qual é totalmente genérico, antes do planejamento dos testes, podendo ser gasto muito tempo nessa atividade. Outro ponto é que o teste torna-se totalmente dependente do hardware. Entretanto, os resultados experimentais apresentados para o estudo de caso do presente trabalho foram satisfatórios. / Society is increasingly dependent on embedded systems, which in most cases operate in an invisible manner to its users. This dependence makes the user vulnerable to risks due to failures that may occur. These failures can cause loss of lives or serious property and financial damage. Because of these facts, the quality of these products becomes a key point to have a stable system, free of errors and with all the features running. This testing is of essential importance to obtain a product with good quality. Due to the high cost of production and energy spent on tests, there is a need for further studies on different methods, to test an embedded system. In this context, this work aims at presenting the initial studies as the testing of the Embedded Operating System. The case study was focused on the exception handling routine of the eCos (Embedded Configurable Operating System), because it has a strong interaction between software and hardware, and this interaction is one of the main challenges encountered in testing embedded software. Therefore, this work aims at taking the first steps towards research related to testing an Embedded Operating System. After analyzing the experiments, it was noted that the main feature of the Embedded Operating System, eCos, the configurability, is an extra point of difficulty for the tests. It requires a detailed study of the code eCos, which is completely general, before the planning of tests, and could be spent much time in this activity. Another point is that the test becomes totally dependent on hardware. However, the experimental results presented for the case study of this study showed satisfactory.

This thesis presents a quantitative evaluation of an operating system virtualization technology known as Solaris Containers or Solaris Zones, with a special emphasis on measuring the influence of a security technology known as Solaris Trusted Extensions. Solaris Zones is an operating system-level (OS-level) virtualization technology embedded in the Solaris OS that primarily provides containment of processes within the abstraction of a complete operating system environment. Solaris Trusted Extensions presents a specific configuration of the Solaris operating system that is designed to offer multi-level security functionality. Firstly, we examine the scalability of the OS with respect to an increasing number of zones. Secondly, we evaluate the performance of zones in three scenarios. In the first scenario we measure - as a baseline - the performance of Solaris Zones on a 2-CPU core machine in the standard configuration that is distributed as part of the Solaris OS. In the second scenario we investigate the influence of the number of CPU cores. In the third scenario we evaluate the performance in the presence of a security configuration known as Solaris Trusted Extensions. To evaluate performance, we calculate a number of metrics using the AIM benchmark. We calculate these benchmarks for the global zone, a non-global zone, and increasing numbers of concurrently running non-global zones. We aggregate the results of the latter to compare aggregate system performance against single zone performance. The results of this study demonstrate the scalability and performance impact of Solaris Zones in the Solaris OS. On our chosen hardware platform, Solaris Zones scales to about 110 zones within a short creation time (i.e., less than 13 minutes per zone for installation, configuration, and boot.) As the number of zones increases, the measured overhead of virtualization shows less than 2% of performance decrease for most measured benchmarks, with one exception: the benchmarks for memory and process management show that performance decreases of 5-12% (depending on the sub-benchmark) are typical. When evaluating the Trusted Extensions-based security configuration, additional small performance penalties were measured in the areas of Disk/Filesystem I/O and Inter Process Communication. Most benchmarks show that aggregate system performance is higher when distributing system load across multiple zones compared to running the same load in a single zone.

The Integrated Modular Avionics architecture , IMA, provides means for runningmultiple safety-critical applications on the same hardware. ARINC 653 is aspecification for this kind of architecture. It is a specification for space and timepartition in safety-critical real-time operating systems to ensure each application’sintegrity. This Master thesis describes how databases can be implementedand used in an ARINC 653 system. The addressed issues are interpartitioncommunication, deadlocks and database storage. Two alternative embeddeddatabases are integrated in an IMA system to be accessed from multiple clientsfrom different partitions. Performance benchmarking was used to study the differencesin terms of throughput, number of simultaneous clients, and scheduling.Databases implemented and benchmarked are SQLite and Raima. The studiesindicated a clear speed advantage in favor of SQLite, when Raima was integratedusing the ODBC interface. Both databases perform quite well and seem to begood enough for usage in embedded systems. However, since neither SQLiteor Raima have any real-time support, their usage in safety-critical systems arelimited. The testing was performed in a simulated environment which makesthe results somewhat unreliable. To validate the benchmark results, furtherstudies must be performed, preferably in a real target environment.The Integrated Modular Avionics architecture , IMA, provides means for runningmultiple safety-critical applications on the same hardware. ARINC 653 is aspecification for this kind of architecture. It is a specification for space and timepartition in safety-critical real-time operating systems to ensure each application’sintegrity. This Master thesis describes how databases can be implementedand used in an ARINC 653 system. The addressed issues are interpartitioncommunication, deadlocks and database storage. Two alternative embeddeddatabases are integrated in an IMA system to be accessed from multiple clientsfrom different partitions. Performance benchmarking was used to study the differencesin terms of throughput, number of simultaneous clients, and scheduling.Databases implemented and benchmarked are SQLite and Raima. The studiesindicated a clear speed advantage in favor of SQLite, when Raima was integratedusing the ODBC interface. Both databases perform quite well and seem to begood enough for usage in embedded systems. However, since neither SQLiteor Raima have any real-time support, their usage in safety-critical systems arelimited. The testing was performed in a simulated environment which makesthe results somewhat unreliable. To validate the benchmark results, furtherstudies must be performed, preferably in a real target environment.

This thesis describes a further development of a building block for programmable devices in embedded systems handling real-time functionality. Embedded systems are included in a variety of products within different technical areas such as industrial automation, consumer electronics, automotive industry, and communication-, and multimedia systems. Products ranging from trains and airplanes to microwave ovens and washing machines are controlled by embedded systems. Programmable devices constitute a part of these embedded systems. Today, a programmable device can include a complete system containing building blocks connected with each other via programs written using a hardware description language. The programmable devices can be programmed and changed over and over again and this flexibility makes it possible to explore how these building blocks can best be designed in relation to system requirements, before final implementation. This thesis describes a further development of a building block for programmable devices implemented in a non-traditional way, i.e., the implementation is written using both hardware description language and traditional software languages. This new building block handles real-time functionality in a non-traditional way that enables certain benefits, such as increased performance, predictability and less memory consumption. Using a non-traditional implementation also has its drawbacks, and e.g., extensions and adjustments can be hard to handle since modifications are required in both hardware and software programming languages. The new building block was investigated in order to see how it could be facilitated when used for real-time functionality. The configurability of the block was extended which enables further customization of the building block. This leads to the possibility to use the block within a wider spectrumof applications. It is also possible to reduce the size and cost of the final product since resource usage can be optimized. Furthermore, a mathematicalmodel estimating resource usage for real-time functionality has been developed. The model enables distinctive trade-offs comparisons, and guidance for system designers, when considering what type of real-time operating system to use in a certain design.

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