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Test Process Assessment of Industrial Control Systems via Safety StandardsPourvatan, Ladan January 2021 (has links)
As more systems are becoming embedded hardware-based, challenges regarding software safety and considerable consequences of their failure arise. Various safety standards assure certain safety aspects of systems, addressing areas including testing. The safety standards chosen for this thesis are ISO/IEC/IEEE 29119-2 & 3, IEC 61508-1 & 3, ISO 13849-1 & 2, and ISO/IEC/IEEE 12207:2017. This thesis tackles the problem of compliance with safety standards by utilising a lightweight assessment method, leading to recommendations for improving the test process of an industrial control system. A case study is performed on an automation company to achieve the objectives of this thesis. The method used for the qualitative data analysis results in recommendations regarding the compliance of the company's test process with selected safety standards. As the final step, the execution of a focus group research leads to the industrial evaluation of the recommendations and assessment results. The company's development process fully complies with 22% and fails to comply with 58% of the extracted requirements from the selected safety standards. Furthermore, the thesis results in recommendations for improving the test process of an industrial control system. As a result of performing the case study, a method for a lightweight assessment of the development process of industrial control systems is achieved. The generic method follows five steps, firstly tabulating the data to attain assessment criteria and items, used by the assessment step to get a compliance degree per requirement. The analysis step comes next to shed light on areas of strength and weakness, leading to recommendations. The final step evaluates and refines the recommendations according to the results of a focus group. Further development of the method used in this thesis can lead to a generic method for assessing development processes, concerning safety standards, using limited resources. The results of this generic method can lead to recommendations for test process improvements of control systems via safety standards.
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Identifiable Radar Reflectors For Automotive Pedestrian SafetyKashyap, Abhilash Nagesh, Madanmohan, Ashwin January 2020 (has links)
Radar plays a major role in safety-critical applications mainly in the automotive industry due to its weather and lighting independence. The progress made in radar hardware technology has made it possible to detect objects more efficiently. Autonomous vehicles need to address a lot of problems encountered in their pathways which need proper detection and identification of obstacles for navigation purposes. Detection and identification of obstacles during navigation help in defining the trajectories for a vehicle so that collision can be avoided. A 77GHz radar system is used in many automotive industrial vehicles for automotive safety. At any given time, there is a possibility of multiple objects being in the vicinity of a vehicle that is not highly reflective which is based on its materialistic properties, such as prams or bicycles as compared to other road vehicles. In the work described in this thesis, we aim at designing, detecting, and identifying simple radar reflectors using copper sheets, which can be placed on such low reflective objects which helps in increasing pedestrian safety aspects. The software aspect of the radar module being used is achieved by using a demo application provided by the radar module manufacturer. This acts as the base structure for the python script which is used for detection and identification of the radar reflectors.
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Kontrollsystem till Markberedare : Styrning till Invers-MarkberedareEkman Svahn, Edvin Benjamin January 2020 (has links)
Syftet med detta examinationsarbete är att utveckla ett kontrollsystem för en inversmarkberedningsprototyp.En simuleringsmodell har skapats för att utveckla ett kontrollsystem med syftet att validera och verifiera prototypens effektivitet. Simuleringsuppställningen är skapad i Simulink, där en del av prototypen är importerad som en solidmodell vilken sammankopplas med en modell av ett hydraulsystem som styr solidmodellens rörelse. I Simuleringsmiljön utvecklades reglering samt styrlogik för prototypen. När regleringen var färdig att testas kontrollerades det att mjukvaran läsa av aktuella sensorer och att utsignaler från kontrollsystemet når hårdvaran, samt att den avsedda rörelsen utförs i verkligheten. Detta projekt har därmed resulterat i en simuleringsmodell, ett kontrollsystem, samt förutsättningar för att kunna verifiera resultaten i verkligheten. / This thesis treats the development of a control system for an inverse soil conditioner prototype. A simulation model was created to develop a control system with the purpose of validation and verification of the prototypes efficacy. The simulation model is created in Simulink, where a part of the soil conditioner is imported as a solid model, which then is coupled to a model of a hydraulic system. In the simulation a control system and regulator were implemented and tuned. when the software was test-ready the hardware-interface was tested to validate that the current software could receive inputs and send meaningful outputs, and then real movements were logged to validate the software function for the machine. The results of this project can then be summarized as a simulation model, a control system, and a solid basis for real world verification are completed.
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Towards TCP/IP for Wireless Sensor NetworksDunkels, Adam January 2005 (has links)
Wireless sensor networks are composed of large numbers-up to thousands-of tiny radio-equipped sensors. Every sensor has a small microprocessor with enough power to allow the sensors to autonomously form networks through which sensor information is gathered. Wireless sensor networks makes it possible to monitor places like nuclear disaster areas or volcano craters without requiring humans to be immediately present. Many wireless sensor network applications cannot be performed in isolation; the sensor network must somehow be connected to monitoring and controlling entities. This thesis investigates a novel approach for connecting sensor networks to existing networks: by using the TCP/IP protocol suite in the sensor network, the sensors can be directly connected to an outside network without the need for special proxy servers or protocol converters. Bringing TCP/IP to wireless sensor networks is a challenging task, however. First, because of their limited physical size and low cost, sensors are severely constrained in terms of memory and processing power. Traditionally, these constraints have been considered too limiting for a sensor to be able to use the TCP/IP protocols. In this thesis, I show that even tiny sensors can communicate using TCP/IP. Second, the harsh communication conditions make TCP/IP perform poorly in terms of both throughput and energy efficiency. With this thesis, I suggest a number of optimizations that are intended to increase the performance of TCP/IP for sensor networks. The results of the work presented in this thesis has had a significant impact on the embedded TCP/IP networking community. The software developed as part of the thesis has become widely known in the community. The software is mentioned in books on embedded systems and networking, is used in academic courses on embedded systems, is the focus of articles in professional magazines, is incorporated in embedded operating systems, and is used in a large number of embedded devices. / Contiki / uIP
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System-Level Techniques for Temperature-Aware Energy OptimizationBao, Min January 2010 (has links)
Energy consumption has become one of the main design constraints in today’s integrated circuits. Techniques for energy optimization, from circuit-level up to system-level, have been intensively researched. The advent of large-scale integration with deep sub-micron technologies has led to both high power densities and high chip working temperatures. At the same time, leakage power is becoming the dominant power consumption source of circuits, due to continuously lowered threshold voltages, as technology scales. In this context, temperature is an important parameter. One aspect, of particular interest for this thesis, is the strong inter-dependency between leakage and temperature. Apart from leakage power, temperature also has an important impact on circuit delay and, implicitly, on the frequency, mainly through its influence on carrier mobility and threshold voltage. For power-aware design techniques, temperature has become a major factor to be considered. In this thesis, we address the issue of system-level energy optimization for real-time embedded systems taking temperature aspects into consideration. We have investigated two problems in this thesis: (1) Energy optimization via temperature-aware dynamic voltage/frequency scaling (DVFS). (2) Energy optimization through temperature-aware idle time (or slack) distribution (ITD). For the above two problems, we have proposed off-line techniques where only static slack is considered. To further improve energy efficiency, we have also proposed online techniques, which make use of both static and dynamic slack. Experimental results have demonstrated that considerable improvement of the energy efficiency can be achieved by applying our temperature-aware optimization techniques. Another contribution of this thesis is an analytical temperature analysis approach which is both accurate and sufficiently fast to be used inside an energy optimization loop.
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Survey of microcontrollers and short-range radio transceivers for wireless sensorsZewdu Yesitla, Ephrem January 2020 (has links)
A significant growth was witnessed in the field of Wireless Sensor Networks (WSNs), in the previous decade. The objective of this study has been Survey of micro controllers and short-range radio transceivers for wireless sensors and provide an extensive overview of micro controllers and RF-transceivers in the Market and compare the relevant properties for designing wireless sensor nodes. In the survey, RF-transvers from Nordic semiconductors is extensively presented for short-rang wireless protocols some of the protocols are RF-Communication Module, Bluetooth Low Energy Module, ZigBee module and Wi-Fi module. In WSNs node design Power consumption is one the most important design issue, this thesis work present the different type of WSN protocols energy consumption efficiency and power consumption, compared and conclude graphically. Microcontrollers are the main part of WSNs node for processing and gathering sensor data. There is different microcontroller’s products in the market however the WSN protocols presented in this thesis uses Cortex-M4 processor which is one of ARM product, the specification and comparison of this product with other products is presented.
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Predictable Real-Time Applications on Multiprocessor Systems-on-ChipRosén, Jakob January 2011 (has links)
Being predictable with respect to time is, by definition, a fundamental requirement for any real-time system. Modern multiprocessor systems impose a challenge in this context, due to resource sharing conflicts causing memory transfers to become unpredictable. In this thesis, we present a framework for achieving predictability for real-time applications running on multiprocessor system-on-chip platforms. Using a TDMA bus, worst-case execution time analysis and scheduling are done simultaneously. Since the worst-case execution times are directly dependent on the bus schedule, bus access design is of special importance. Therefore, we provide an efficient algorithm for generating bus schedules, resulting in a minimized worst-case global delay. We also present a new approach considering the average-case execution time in a predictable context. Optimization techniques for improving the average-case execution time of tasks, for which predictability with respect to time is not required, have been investigated for a long time in many different contexts. However, this has traditionally been done without paying attention to the worst-case execution time. For predictable real-time applications, on the other hand, the focus has been solely on worst-case execution time optimization, ignoring how this affects the execution time in the average case. In this thesis, we show that having a good average-case global delay can be important also for real-time applications, for which predictability is required. Furthermore, for real-time applications running on multiprocessor systems-on-chip, we present a technique for optimizing for the average case and the worst case simultaneously, allowing for a good average case execution time while still keeping the worst case as small as possible. The proposed solutions in this thesis have been validated by extensive experiments. The results demonstrate the efficiency and importance of the presented techniques.
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Data Link Layer Security for Spacecraft Communication Implementation on FPGASundberg, Sarah January 2020 (has links)
With increasing awareness of potential security threats there is a growing interest in communication security for spacecraft control and data. Traditionally commercial and scientific missions have relied on their uniqueness to prevent security breaches. During time the market has changed with open systems for mission control and data distribution, increased connectivity and the use of existing and shared infrastructure. Therefore security layers are being introduced to protect spacecraft communication. In order to mitigate the perceived threats, the Consultative Committee for Space Data Systems (CCSDS) has proposed the addition of communication security in the various layers of the communication model. This thesis describes and discuss their proposal and look into how this application should be implemented into the data link layer of the communication protocol to protect from timing attacks. An implementation of AES-CTR+GMAC is constructed in software to compare different key lengths and another implementation is constructed in synthesized VHDL for use on hardware to investigate the impact on area consumption on the FPGA as well as if it is possible to secure it from cache-timing attacks.
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Évolution des Architectures des Systèmes Avioniques Embarqués / Evolution of the embedded avionics systems architectureGatti, Marc 14 June 2016 (has links)
De nos jours, les systèmes embarqués sont les éléments Cœurs des Systèmes avioniques. De plus en plus de fonctions sont intégrées et de ce fait leurs complexités croît. Afin que cette complexité puisse rester maîtrisable, l’architecture des systèmes avionique a également évolué de façon à minimiser les interactions entre les équipements. Cette évolution des Architectures a introduit, au niveau avionique, la notion de réseau largement répandue dans le monde dit « consumer ». Nos travaux de Recherche ont pour but d’accompagner cette évolution architecturale en minimisant l’impact des ruptures technologiques qu’il a été nécessaire d’introduire afin de supporter cette évolution. Pour cela, nous proposons une approche qui va nous permettre de dé-risquer chaque nouvelle brique technologique avant son introduction au sein des Systèmes Embarqués. Cette introduction pourra donc être réalisée en ayant au préalable défini les conditions ainsi que les limites d’utilisation de chaque nouvelle technologie, qu’elle soit matérielle et/ou logicielle. / Nowadays, Embedded Systems are key elements of the Avionic Systems. As more and more functions are integrated, their complexity goes increasing. In order to keep mastering this complexity, Avionic Systems Architecture has also evolved so as to minimize the interactions between equipment. This evolution of the Architectures introduced, at the avionic level, the notion of network widely spread in the consumer domain. Our research works aim at accompanying this architectural evolution by minimizing the impact of the technological breakthroughs which were necessary to introduce to support this evolution. For that purpose, we propose an approach which is going to allow us to derisk every new technological brick before its introduction within the Embedded Systems. This introduction can thus be performed by having beforehand defined the conditions as well as the limits of use of every new technology that it is Hardware and/or Software.
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Vers une utilisation efficace des processeurs multi-coeurs dans des systèmes embarqués à criticités multiples / Towards an efficient use of multi-core processors in mixed criticality embedded systemsBlin, Antoine 30 January 2017 (has links)
Les systèmes embarqués dans les véhicules comportent un mélange d’applications temps réel et « best effort » déployées, pour des raisons d’isolation, sur des calculateurs séparés. L’ajout de nouvelles fonctionnalités dans les véhicules se traduit par un accroissement du nombre de calculateurs et ainsi par une augmentation des coûts, de la consommation électrique et de la dissipation thermique.L’émergence de nouvelles plate-formes multi-cœurs à bas coûts permet d’envisager le déploiement d’une nouvelle architecture dite « virtualisée » pour exécuter en parallèle sur un même calculateur les deux types d’applications. Néanmoins, la hiérarchie mémoire de tels calculateurs, reste partagée. Une application temps réel exécutée sur un cœur peut donc voir ses temps d’accès à la mémoire ralentis par les accès effectués par les applications « best effort » exécutées en parallèle entraînant ainsi la violation des échéances de la tâche temps réel.Dans cette thèse, nous proposons une nouvelle approche de gestion de la contention mémoire. Dans une première étape, hors ligne, nous générons un oracle capable d’estimer les ralentissements d’une tâche temps réel en fonction du trafic mémoire mesuré. Dans une deuxième étape, en ligne, les tâches temps réel sont exécutées en parallèle des applications « best effort ». Un mécanisme de régulation va surveiller la consommation mémoire et utiliser l’oracle généré précédemment pour estimer le ralentissement des tâches temps réel. Lorsque le ralentissement estimé est supérieur à celui fixé par le concepteur du système les applications « best effort » sont suspendues jusqu’à ce que l’application temps réel termine son activation. / Complex embedded systems today commonly involve a mix of real-time and best-effort applications integrated on separate microcontrollers thus ensuring fault isolation and error containment. However, this solution multiplies hardware costs, power consumption and thermal dissipation.The recent emergence of low-cost multi-core processors raises the possibility of running both kinds of applications on a single machine, with virtualization ensuring isolation. Nevertheless, the memory hierarchy on such processors is shared between all cores. Memory accesses done by a real time application running on one dedicated core can be slowed down by concurrent memory accesses initiated by best effort applications running in parallels. Therefore real time applications can miss their deadlines.In this thesis, we propose a run-time software-regulation approach that aims to maximize parallelism between real-time and best-effort applications running on a single low-cost multicore ECU. Our approach uses an overhead estimation derived from offline profiling of the real-time application to estimate the slow down on the real-time application caused by memory interferences. When the estimated overhead reaches a predefined threshold, our approach suspends the best-effort applications, allowing the real-time task to continue executing without interferences. Suspended best-effort applications are resumed when the real-time application ends its current activation.
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