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Après le lancement du premier satellite artificiel en 1957, l'évolution de diverses technologies a favorisé la miniaturisation des satellites. En 1999, le développement des nano-satellites modulaires appelés CubeSats, qui ont la forme d'un cube d'un décimètre de côté et une masse de 1 kg à 10 kg, a été initié par un effort commun de l'Université polytechnique de Californie et de l'Université de Stanford. Depuis lors, grâce à l’utilisation de composants électroniques standards à faible coût, les CubeSats se sont largement répandus.Au cours des dernières années, le nombre de CubeSats lancés a régulièrement augmenté, mais moins de la moitié des missions ont atteint leurs objectifs. L'analyse des défaillances des CubeSats montre que la cause la plus évidente est le manque d’essais adéquats des composants du système ou du système au complet. Parmi les tâches particulièrement difficiles, on compte les essais « hardware-in-the-loop » (HIL) du système de contrôle d'attitude et d'orbite (SCAO) d’un CubeSat. Un système dédié à ces essais doit permettre des simulations fiables de l'environnement spatial et des mouvements réalistes des CubeSats. La façon la plus appropriée d’obtenir de telles conditions d’essai repose sur l’utilisation d’un coussin d'air. Toutefois, les mouvements du satellite sont alors contraints par les limites géométriques, qui sont inhérentes aux coussins d'air. De plus, après 15 années de développements de CubeSats, la liste des systèmes proposés pour tester leur SCAO reste très limitée.Aussi, cette thèse est consacrée à l’étude et à la conception d’un système robotique innovant pour des essais HIL du SCAO d’un CubeSat. La nouveauté principale du système d'essai proposé est l’usage de quatre coussins d'air au lieu d'un seul et l’emploi d’un robot manipulateur. Ce système doit permettre des mouvements non contraints du CubeSat. Outre la conception du système d'essai, cette thèse porte sur les questions liées: (i) à la détermination de l'orientation d’un CubeSat au moyen de mesures sans contact; (ii) au comportement de l’assemblage des coussins d'air; (iii) à l'équilibrage des masses du système.Afin de vérifier la faisabilité de la conception proposée, un prototype du système d'essai a été développé et testé. Plusieurs modifications destinées à en simplifier la structure et à réduire le temps de fabrication ont été effectuées. Un robot Adept Viper s650 est notamment utilisé à la place d'un mécanisme sphérique spécifiquement conçu. Une stratégie de commande est proposée dans le but d’assurer un mouvement adéquat du robot qui doit suivre les rotations du CubeSat. Finalement, les résultats obtenus sont présentés et une évaluation globale du système d'essai est discutée. / After the launch of the first artificial Earth satellite in 1957, the evolution of various technologies has fostered the miniaturization of satellites. In 1999, the development of standardized modular satellites with masses limited to a few kilograms, called CubeSats, was initiated by a joint effort of California Polytechnic State University and Stanford University. Since then, CubeSats became a widespread and significant trend, due to a number of available off-the-shelf low cost components.In last years, the number of launched CubeSats constantly grows, but less than half of all CubeSat missions achieved their goals (either partly or completely). The analysis of these failures shows that the most evident cause is a lack of proper component-level and system-level CubeSat testing. An especially challenging task is Hardware-In-the-Loop (HIL) tests of the Attitude Determination and Control System (ADCS). A system devoted to these tests shall offer reliable simulations of the space environment and allow realistic CubeSat motions. The most relevant approach to provide a satellite with such test conditions consists in using air bearing platforms. However, the possible satellite motions are strictly constrained because of geometrical limitations, which are inherent in the air bearing platforms. Despite 15 years of CubeSat history, the list of the air bearing platforms suitable for CubeSat ADCS test is very limited.This thesis is devoted to the design and development of an air bearing testbed for CubeSat ADCS HIL testing. The main novelty of the proposed testbed design consists in using four air bearings instead of one and in utilizing a robotic arm, which allows potentially unconstrained CubeSat motions. Besides the testbed design principle, this thesis deals with the related issues of the determination of the CubeSat orientation by means of contactless measurements, and of the behavior of the air bearings, as well as with the need of a mass balancing method.In order to verify the feasibility of the proposed design, a prototype of the testbed is developed and tested. Several modifications aimed at simplifying the structure and at shortening the fabrication timeline have been made. For this reason, the Adept Viper s650 robot is involved in place of a custom-designed 4DoF robotic arm. A control strategy is proposed in order to provide the robot with a proper motion to follow the CubeSat orientation. Finally, the obtained results are presented and the overall assessment of the proposed testbed is put into perspective.

A definição de abordagens de teste de software no contexto de sistemas embarcados críticos é de fundamental importância para a melhoria de qualidade desses sistemas. Este projeto de mestrado concentra-se essencialmente na área de robôs móveis que são sistemas críticos. O mapeamento das técnicas de teste dos programas tradicionais para sistemas robóticos móveis não é trivial, pois é necessário considerar as características inerentes a esses sistemas, as quais incluem comunicação, sincronização, não determinismo e paralelismo. Esses sistemas são formados por diferentes componentes, como sensores, atuadores e softwares de controle, os quais se comunicam, em geral, por meio de troca de mensagens. Nesse sentido, este projeto visa aproveitar a experiência adquirida pelo grupo de pesquisa do ICMC/USP com a proposição de critérios e ferramentas de teste para programas concorrentes, para o contexto de teste de integração de sistemas robóticos móveis. Assim, neste estudo é apresentado um comparativo sobre as similaridades e diferenças presentes em programas concorrentes e sistemas robóticos móveis com objetivo de auxiliar na adaptação dos critérios de teste. Dois estudos de caso foram conduzidos nos quais os critérios propostos para programas concorrentes foram aplicados a sistemas robóticos desenvolvidos em ROS. Como resultados, observou-se os critérios de teste são capazes de testar adequadamente aspectos de comunicação e sincronização de sistemas robóticos, contribuindo com a qualidade desses sistemas. / The definition of software testing approaches for the context of critical embedded systems is of fundamental importance for the quality improvement of these systems. This masters project focuses primarily in mobile robot area that are critical systems. The mapping of traditional testing techniques for robotic mobile systems is not trivial, because it is necessary to consider the characteristics of these systems, which include communication, synchronization, non-determinism and parallelism. These systems present different components such as sensors, actuators and control software, which communicate, usually by exchanging messages. In this sense, this project aims to use on the experience gained by the research group of the ICMC/USP with the of the concurrent program testing criteria for the integration testing of the mobile robotic systems. In this study we present a comparison of the similarities and differences present in concurrent programs and mobile robotic systems in order to assist in adapting the testing criteria. Two case studies were conducted in which the proposed concurrent program testing criteri were applied to robotic systems developed in ROS. As a result, there was the testing criteria are able to properly testing aspects of communication and synchronization of robotic systems, contributing to the quality of these systems.

Serial manipulators, which have large work space with respect to their own volume and occupied floor space, are the most common industrial robots by far. However, in many environments the situation is unstructured and less predictable, such as aboard a space station, a nuclear waste retrieval site, or a lunar base construction site. It is almost impossible to design a single robotic system which can meet all the requirements for every task. In these circumstances, it is important to deploy a modular reconfigurable robotic system, which is suitable to various task requirements. Modular reconfigurable robots have a variety of attributes that are well suited to for these conditions, including: the ability to serve as many different tools at once (saving weight), packing into compressed forms (saving space) and having high levels of redundany(increasing robustness). By easy disassembly and reassembly features, this serial modular robotic system will bring advantages to small and medium enterprise to save costs in the long term. This thesis focuses on developing such a serial reconfigurable modular robotic system with remote control functionality. The robotic arms are assembled by PowerCube Modules with cubic outward appearance. The control and power electronics are fully integrated on the connector block inside of the modules. Those modules are connected in series by looping through, and can work completely independently. The communication between robotic arms and PC controller is connected by the Control Area Network bus. CAN protocol detects and corrects transmission errors caused by electromagnetic interference. The local PC can directly control the robotic arm via Visual Basic code, and it can also be treated as server controller. Client PCs can access and control the robotic arm remotely through Socket communication mechanism with certain IP address and port number. A Java3D model is created on the client PC synchronously for customers online monitoring and control. The forward and inverse kinematic analysis is solved by Vector Algebraic Method. The Neutral Network Method is also introduced to improve the kinematic analysis. Multiple-layer networks are capable of approximating any function with finite number of discontinuities. For learning the inverse kinematics neural network needs information about coordinates, joint angles and actuator positions. The desired Cartesian coordinates are given as input to the neural network that returns actuator positions as output. The robot position is simulated using these actuator positions as reference values for each actuator.

A definição de abordagens de teste de software no contexto de sistemas embarcados críticos é de fundamental importância para a melhoria de qualidade desses sistemas. Este projeto de mestrado concentra-se essencialmente na área de robôs móveis que são sistemas críticos. O mapeamento das técnicas de teste dos programas tradicionais para sistemas robóticos móveis não é trivial, pois é necessário considerar as características inerentes a esses sistemas, as quais incluem comunicação, sincronização, não determinismo e paralelismo. Esses sistemas são formados por diferentes componentes, como sensores, atuadores e softwares de controle, os quais se comunicam, em geral, por meio de troca de mensagens. Nesse sentido, este projeto visa aproveitar a experiência adquirida pelo grupo de pesquisa do ICMC/USP com a proposição de critérios e ferramentas de teste para programas concorrentes, para o contexto de teste de integração de sistemas robóticos móveis. Assim, neste estudo é apresentado um comparativo sobre as similaridades e diferenças presentes em programas concorrentes e sistemas robóticos móveis com objetivo de auxiliar na adaptação dos critérios de teste. Dois estudos de caso foram conduzidos nos quais os critérios propostos para programas concorrentes foram aplicados a sistemas robóticos desenvolvidos em ROS. Como resultados, observou-se os critérios de teste são capazes de testar adequadamente aspectos de comunicação e sincronização de sistemas robóticos, contribuindo com a qualidade desses sistemas. / The definition of software testing approaches for the context of critical embedded systems is of fundamental importance for the quality improvement of these systems. This masters project focuses primarily in mobile robot area that are critical systems. The mapping of traditional testing techniques for robotic mobile systems is not trivial, because it is necessary to consider the characteristics of these systems, which include communication, synchronization, non-determinism and parallelism. These systems present different components such as sensors, actuators and control software, which communicate, usually by exchanging messages. In this sense, this project aims to use on the experience gained by the research group of the ICMC/USP with the of the concurrent program testing criteria for the integration testing of the mobile robotic systems. In this study we present a comparison of the similarities and differences present in concurrent programs and mobile robotic systems in order to assist in adapting the testing criteria. Two case studies were conducted in which the proposed concurrent program testing criteri were applied to robotic systems developed in ROS. As a result, there was the testing criteria are able to properly testing aspects of communication and synchronization of robotic systems, contributing to the quality of these systems.

The aim of diploma theses is the design of an adaptive robotic workplace. The theoretical part focus on the division of robotic systems and the technical description of individual devices that were used in the implementation of the solution. The practical part contains an analysis of solutions and optimization of the entire production process in terms of minimizing the trajectory, smoothness of movements, time interval, which were analyzed in RoboSim software and in Roboshop software source code was created. Part of the theses is the design for an adaptive production process. The result of the work is an algorithm for controlling robot movements between individual processes. The theses contain a variant solution and possible innovative solutions for possible expansion of the workplace.

This thesis describes the design and construction of modular robotic system. Proposal of its management and simulation parameters given.

The theme of the thesis is a structural design of the robotic system SCARA. Thesis at the start clarifies the definition of robots and industrial robots. Next it deals with kinematic structures, from basic to more advnced structures, including SCARA type robot. The next chapter describes parts used in design of industrial robots. In the fourth chapter, the table provides an overview of currently available SCARA robots and their attributes. The rest of the thesis itself consists of machine design from determining the required parameters to 3D design. This section also contains extensive computational parts and justifies the choice of the components.

Robotic systems are known to be computationally intensive. To improve performance, developers tend to implement custom robotic algorithms in hardware. However, a full robotic system typically consists of many interconnected algorithmic components that can easily max-out FPGA resources, thus requiring the designer to adjust each algorithm design for each new robotic systems in order to meet specific systems requirements and limited resources. Furthermore, manual development of digital circuitry using a hardware description language (HDL) such as verilog or VHDL, is error-prone, time consuming, and often takes months or years to develop and verify. Recent developments in high-level synthesis (HLS), enable automatic generation of digital circuit designs from high-level languages such as C or C++. In this thesis, we propose to develop a database of HLS-generated pareto-optimal hardware designs for various robotic algorithms, such that a fully automated process can optimally compose a complete robotic system given a set of system requirements. In the first part of this thesis, we take a first step towards this goal by developing a system for automatic selection of an Occupancy Grid Mapping (OGM) implementation given specific system requirements and resource thresholds. We first generate hundreds of possible hardware designs via Vitis HLS as we vary parameters to explore the designs space. We then present results which evaluate and explore trade-offs of these designs with respect to accuracy, latency, resource utilization, and power. Using these results, we create a software tool which is able to automatically select an optimal OGM implementation. After implementing selected designs on a PYNQ-Z2 FPGA board, our results show that the runtime of the algorithm improves by 35x over a C++-based implementation. In the second part of this thesis, we extend these same techniques to the Particle Filter (PF) algorithm by implementing 7 different resampling methods and varying parameters on hardware, again via HLS. In this case, we are able to explore and analyze thousands of PF designs. Our evaluation results show that runtime of the algorithm using Local Selection Resampling method reaches the fastest performance on an FPGA and can be as much as 10x faster than in C++. Finally, we build another design selection tool that automatically generates an optimal PF implementation from this design space for a given query set of requirements.