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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
181

Design Flow für IP basierte, dynamisch rekonfigurierbare, eingebettete Systeme

Meisel, André 22 June 2010 (has links)
Der achte Band der wissenschaftlichen Schriftenreihe EINGEBETTETE, SELBSTORGANISIERENDE SYSTEME widmet sich der Synthese von partiell dynamisch rekonfigurierbaren, eingebetteten Systemen. Mit der Möglichkeit Hardwareblöcke zur Laufzeit auf programmierbaren Bausteinen neu zu konfigurieren, lässt sich eine höhere Flexibilität im Vergleich zu einer Hardwarerealisierung in eingebettete Systeme integrieren. Gleichzeitig sind diese Systeme durch eine gesteigerte Performance gegenüber Software gekennzeichnet. Die Flexibilität kann ausgenutzt werden, um kleinere Schaltkreise bei gleichem Funktionsumfang einzusetzen. Für die Integration von Rekonfigurierung sind zusätzliche Entwurfschritte im Design Flow notwendig. Herr Meisel stellt hierfür in seiner Arbeit eine Entwurfsmethodik vor und geht im Besonderen auf die Partitionierung, Platzierung und Steuerung in dynamisch rekonfigurierbaren, eingebetteten Systemen ein. Um eine vergleichsweise effizient zu realisierende Partitionierung des Systems zu erhalten, wurde das Overlaying Verfahren aus dem Bereich der Speicherverwaltung für dynamische Rekonfigurierung adaptiert. Für das Platzierungsverfahren wurden Rekonfigurierungen als Markov Kette modelliert, um so zu einer Minimierung der durchschnittlichen Rekonfigurierungsdauer zu gelangen. Die vorgestellte Rekonfigurierungssteuerung fokussiert auf einer ressourcensparenden Hardware Implementierung. Mit einem Entwurfsbeispiel werden die Vorteile und Ergebnisse des Ansatzes anschaulich illustriert. So kann der Leser die Mächtigkeit des entwickelten Ansatzes nachvollziehen und wird motiviert, die entwickelte Methodik auf weitere Anwendungsfälle zu übertragen. / Volume 8 of scientific series EINGEBETTETE, SELBSTORGANISIERENDE SYSTEME (Embedded Self-Organized Systems) addresses the synthesis of partially dynamically reconfigurable embedded systems. With the ability to configure hardware blocks during run-time, more flexibility can be integrated in embedded systems. At the same time, these systems have better performance than functions implemented in software. Through this flexibility it is possible to use smaller circuits without limiting the functionality. For the integration of reconfiguration into embedded systems, additional design steps are required. Mr. Meisel presents a design methodology for the design flow and primarily concerns the problem of partitioning, placement, and reconfiguration control in dynamically reconfigurable embedded systems. The implemented partitioning of the system is based on the adapted memory management concept of Overlaying. For the placement method the configurations are modeled as Markov chain, in order to minimize the average reconfiguration time. The presented reconfiguration control unit focuses on a resource-saving hardware implementation. The benefits and results of the approach are clearly illustrated with a design sample. The reader can understand the power of developed approach and is motivated to transfer the developed methodology to more use cases.
182

Digitální osciloskop na platformě FITkit / Digital Oscilloscope on FITkit Platform

Veškrna, Ondřej Unknown Date (has links)
This thesis deals with the design of a device that enables to monitor the behavior of the measured signal on the computer screen, using the principle of the digital oscilloscope. The control element of the device is the field programmable gate array (FPGA) on FITkit platform.  The FPGA configuration controls the input signal sampling and sends the received samples through the USB interface to the PC. The graphical application implemented in the computer tries to restore the signal and then displays it on the screen.
183

Parallel Hardware- and Software Threads in a Dynamically Reconfigurable System on a Programmable Chip

Rößler, Marko 06 December 2013 (has links)
Today’s embedded systems depend on the availability of hybrid platforms, that contain heterogeneous computing resources such as programmable processors units (CPU’s or DSP’s) and highly specialized hardware cores. These platforms have been scaled down to integrated embedded system-on-chip. Modern platform FPGAs enhance such systems by the flexibility of runtime configurable silicon. One of the major advantages that arises is the ability to use hardware (HW) and software (SW) resources in a time-shared manner. Though the ability to dynamically assign computing resources based on decisions taken at runtime is given.
184

Hardware in Loop Simulations of Electric Drives / Hårdvara i Loop Simuleringar av Elektriska Enheter

Deshpante, Varad January 2023 (has links)
Electric drives are crucial components of powertrain of modern vehicles. They need to be controlled effectively to deliver a comfortable and efficient driving experience. The control unit needs to be robust to handle extreme operating conditions and faults in a safe manner. Hardware in Loop (HIL) setups can be used to develop such control units for majority of real-life test cases, without involving physical drives. Typical HIL setup includes the controller (hardware) under test connected to a high fidelity computer model of the controlled system (plant). Thanks to the efficient, inexpensive, consistent and nondestructive nature of HIL setups, they are widely used for research and development in the automotive industry. This thesis focuses on developing such a HIL setup for latest electric drive architecture at Scania CV AB. In this thesis, the plant models are programmed onto a field programmable gate array (FPGA). The HIL setup, plant models and the controller are continuously improved throughout the thesis to achieve higher fidelity and real time replication of the internal permanent magnet synchronous machine under consideration. Software in Loop (SIL) strategy, wherein all components are represented by computer models, is also applied for rapid developments. Several aspects like flux linkage-based and inductance-based machine models, choice of arithmetic, discretization methods, noise, delays, etc. are studied and optimised during the thesis. Validation is conducted for both SIL and HIL setups and above 95% correlation with physical drive’s performance is reported. Stable operation and repeatability of the developed HIL setup ensure that the framework is scalable to be applied to other drives and control units. / Elektriska drivenheter är centrala komponenter i drivlinan hos moderna elektriska fordon. Drivenheterna måste regleras effektivt för att ge en bekväm och effektiv körupplevelse. Regulatorn måste vara robust för att säkert hantera extrema driftsförhållanden och fel. Hardware in Loop (HIL) simuleringar kan användas för att utveckla sådana regulatorer för de flesta verkliga testfall, utan att involvera de fysiska komponenterna. En typisk HIL-installation inkluderar styrenheten (hårdvaran) som testas ansluten till en datormodell av det kontrollerade systemet (anläggningen). På grund av den effektiva, billiga, konsekventa och oförstörande naturen hos HIL simuleringar används de i stor utsträckning för FoU inom fordonsindustrin. Detta examensarbete fokuserar på att utveckla en sådan HIL-modell för en elektrisk drivlina hos Scania CV AB. I detta examensarbete är anläggningsmodellerna programmerade på en programmerbar integrerad krets. HIL-inställningen, anläggningsmodellerna och styrenheten förbättras kontinuerligt under hela examensarbetet för att uppnå högre kvalitet och realtidsreplikering av den permanentmagnetiserade synkronmaskin som övervägs. En Software in Loop (SIL) strategi, där alla komponenter representeras av datormodeller, tillämpas också för snabb utveckling. Flera aspekter såsom flödesbaserade och induktansbaserade maskinmodeller, val av aritmetik, diskretiserings metoder, brus, fördröjningar etc. studeras och optimeras. Validering utförs för både SIL- och HIL-inställningar och över 95% korrelation med fysiska enhetsprestanda erhålls. Stabil drift och repeterbarhet av den utvecklade HIL-kretsen säkerställer att ramverket är skalbart för att kunna appliceras på andra enheter och regulatorer.
185

DEVELOPMENT OF A TRANSFORM-DOMAIN INSTRUMENTATION GLOBAL POSITIONING SYSTEM RECEIVER FOR SIGNAL QUALITY AND ANOMALOUS EVENT MONITORING

Gunawardena, Sanjeev 02 August 2007 (has links)
No description available.
186

Enhancing Trust in Autonomous Systems without Verifying Software

Stamenkovich, Joseph Allan 12 June 2019 (has links)
The complexity of the software behind autonomous systems is rapidly growing, as are the applications of what they can do. It is not unusual for the lines of code to reach the millions, which adds to the verification challenge. The machine learning algorithms involved are often "black boxes" where the precise workings are not known by the developer applying them, and their behavior is undefined when encountering an untrained scenario. With so much code, the possibility of bugs or malicious code is considerable. An approach is developed to monitor and possibly override the behavior of autonomous systems independent of the software controlling them. Application-isolated safety monitors are implemented in configurable hardware to ensure that the behavior of an autonomous system is limited to what is intended. The sensor inputs may be shared with the software, but the output from the monitors is only engaged when the system violates its prescribed behavior. For each specific rule the system is expected to follow, a monitor is present processing the relevant sensor information. The behavior is defined in linear temporal logic (LTL) and the associated monitors are implemented in a field programmable gate array (FPGA). An off-the-shelf drone is used to demonstrate the effectiveness of the monitors without any physical modifications to the drone. Upon detection of a violation, appropriate corrective actions are persistently enforced on the autonomous system. / Master of Science / Autonomous systems are surprisingly vulnerable, not just from malicious hackers, but from design errors and oversights. The lines of code required can quickly climb into the millions, and the artificial decision algorithms can be inscrutable and fully dependent upon the information they are trained on. These factors cause the verification of the core software running our autonomous cars, drones, and everything else to be prohibitively difficult by traditional means. Independent safety monitors are implemented to provide internal oversight for these autonomous systems. A semi-automatic design process efficiently creates error-free monitors from safety rules drones need to follow. These monitors remain separate and isolated from the software typically controlling the system, but use the same sensor information. They are embedded in the circuitry and act as their own small, task-specific processors watching to make sure a particular rule is not violated; otherwise, they take control of the system and force corrective behavior. The monitors are added to a consumer off-the-shelf (COTS) drone to demonstrate their effectiveness. For every rule monitored, an override is triggered when they are violated. Their effectiveness depends on reliable sensor information as with any electronic component, and the completeness of the rules detailing these monitors.
187

Implementation of Bolt Detection and Visual-Inertial Localization Algorithm for Tightening Tool on SoC FPGA / Implementering av bultdetektering och visuell tröghetslokaliseringsalgoritm för åtdragningsverktyg på SoC FPGA

Al Hafiz, Muhammad Ihsan January 2023 (has links)
With the emergence of Industry 4.0, there is a pronounced emphasis on the necessity for enhanced flexibility in assembly processes. In the domain of bolt-tightening, this transition is evident. Tools are now required to navigate a variety of bolts and unpredictable tightening methodologies. Each bolt, possessing distinct tightening parameters, necessitates a specific sequence to prevent issues like bolt cross-talk or unbalanced force. This thesis introduces an approach that integrates advanced computing techniques with machine learning to address these challenges in the tightening areas. The primary objective is to offer edge computation for bolt detection and tightening tools' precise localization. It is realized by leveraging visual-inertial data, all encapsulated within a System-on-Chip (SoC) Field Programmable Gate Array (FPGA). The chosen approach combines visual information and motion detection, enabling tools to quickly and precisely do the localization of the tool. All the computing is done inside the SoC FPGA. The key element for identifying different bolts is the YOLOv3-Tiny-3L model, run using the Deep-learning Processor Unit (DPU) that is implemented in the FPGA. In parallel, the thesis employs the Error-State Extended Kalman Filter (ESEKF) algorithm to fuse the visual and motion data effectively. The ESEKF is accelerated via a full implementation in Register Transfer Level (RTL) in the FPGA fabric. We examined the empirical outcomes and found that the visual-inertial localization exhibited a Root Mean Square Error (RMSE) position of 39.69 mm and a standard deviation of 9.9 mm. The precision in orientation determination yields a mean error of 4.8 degrees, offset by a standard deviation of 5.39 degrees. Notably, the entire computational process, from the initial bolt detection to its final localization, is executed in 113.1 milliseconds. This thesis articulates the feasibility of executing bolt detection and visual-inertial localization using edge computing within the SoC FPGA framework. The computation trajectory is significantly streamlined by harnessing the adaptability of programmable logic within the FPGA. This evolution signifies a step towards realizing a more adaptable and error-resistant bolt-tightening procedure in industrial areas. / Med framväxten av Industry 4.0, finns det en uttalad betoning på nödvändigheten av ökad flexibilitet i monteringsprocesser. Inom området bultåtdragning är denna övergång tydlig. Verktyg krävs nu för att navigera i en mängd olika bultar och oförutsägbara åtdragningsmetoder. Varje bult, som har distinkta åtdragningsparametrar, kräver en specifik sekvens för att förhindra problem som bultöverhörning eller obalanserad kraft. Detta examensarbete introducerar ett tillvägagångssätt som integrerar avancerade datortekniker med maskininlärning för att hantera dessa utmaningar i skärpningsområdena. Det primära målet är att erbjuda kantberäkning för bultdetektering och åtdragningsverktygs exakta lokalisering. Det realiseras genom att utnyttja visuella tröghetsdata, allt inkapslat i en System-on-Chip (SoC) Field Programmable Gate Array (FPGA). Det valda tillvägagångssättet kombinerar visuell information och rörelsedetektering, vilket gör det möjligt för verktyg att snabbt och exakt lokalisera verktyget. All beräkning sker inuti SoC FPGA. Nyckelelementet för att identifiera olika bultar är YOLOv3-Tiny-3L-modellen, som körs med hjälp av Deep-learning Processor Unit (DPU) som är implementerad i FPGA. Parallellt använder avhandlingen algoritmen Error-State Extended Kalman Filter (ESEKF) för att effektivt sammansmälta visuella data och rörelsedata. ESEKF accelereras via en fullständig implementering i Register Transfer Level (RTL) i FPGA-strukturen. Vi undersökte de empiriska resultaten och fann att den visuella tröghetslokaliseringen uppvisade en Root Mean Square Error (RMSE) position på 39,69 mm och en standardavvikelse på 9,9 mm. Precisionen i orienteringsbestämningen ger ett medelfel på 4,8 grader, kompenserat av en standardavvikelse på 5,39 grader. Noterbart är att hela beräkningsprocessen, från den första bultdetekteringen till dess slutliga lokalisering, exekveras på 113,1 millisekunder. Denna avhandling artikulerar möjligheten att utföra bultdetektering och visuell tröghetslokalisering med hjälp av kantberäkning inom SoC FPGA-ramverket. Beräkningsbanan är avsevärt effektiviserad genom att utnyttja anpassningsförmågan hos programmerbar logik inom FPGA. Denna utveckling innebär ett steg mot att förverkliga en mer anpassningsbar och felbeständig skruvdragningsprocedur i industriområden.
188

Digital control strategies for DC/DC SEPIC converters towards integration / Stratégies de commande numérique pour un convertisseur DC/DC SEPIC en vue de l’intégration

Li, Nan 29 May 2012 (has links)
L’utilisation des alimentations à découpage (SMPSs : switched mode power supplies) est à présent largement répandue dans des systèmes embarqués en raison de leur rendement. Les exigences technologiques de ces systèmes nécessitent simultanément une très bonne régulation de tension et une forte compacité des composants. SEPIC (Single-Ended Primary Inductor Converter) est un convertisseur à découpage DC/DC qui possède plusieurs avantages par rapport à d’autres convertisseurs de structure classique. Du fait de son ordre élevé et de sa forte non linéarité, il reste encore peu exploité. L’objectif de ce travail est d’une part le développement des stratégies de commande performantes pour un convertisseur SEPIC et d’autre part l’implémentation efficace des algorithmes de commande développés pour des applications embarquées (FPGA, ASIC) où les contraintes de surface silicium et le facteur de réduction des pertes sont importantes. Pour ce faire, deux commandes non linéaires et deux observateurs augmentés (observateurs d’état et de charge) sont exploités : une commande et un observateur fondés sur le principe de mode de glissement, une commande prédictive et un observateur de Kalman étendu. L’implémentation des deux lois de commande et l’observateur de Kalman étendu sont implémentés sur FPGA. Une modulation de largeur d’impulsion (MLI) numérique à 11-bit de résolution a été développée en associant une technique de modulation Δ-Σ de 4-bit, un DCM (Digital Clock Management) segmenté et déphasé de 4-bit, et un compteur-comparateur de 3-bit. L’ensemble des approches proposées sont validées expérimentalement et constitue une bonne base pour l’intégration des convertisseurs à découpage dans les alimentations embarquées. / The use of SMPS (Switched mode power supply) in embedded systems is continuously increasing. The technological requirements of these systems include simultaneously a very good voltage regulation and a strong compactness of components. SEPIC ( Single-Ended Primary Inductor Converter) is a DC/DC switching converter which possesses several advantages with regard to the other classical converters. Due to the difficulty in control of its 4th-order and non linear property, it is still not well-exploited. The objective of this work is the development of successful strategies of control for a SEPIC converter on one hand and on the other hand the effective implementation of the control algorithm developed for embedded applications (FPGA, ASIC) where the constraints of Silicon surface and the loss reduction factor are important. To do it, two non linear controls and two observers of states and load have been studied: a control and an observer based on the principle of sliding mode, a deadbeat predictive control and an Extended Kalman observer. The implementation of both control laws and the Extended Kalman observer are implemented in FPGA. An 11-bit digital PWM has been developed by combining a 4-bit Δ-Σ modulation, a 4-bit segmented DCM (Digital Clock Management) phase-shift and a 3-bit counter-comparator. All the proposed approaches are experimentally validated and constitute a good base for the integration of embedded switching mode converters
189

300 MBPS CCSDS Processing Using FPGA's

Genrich, Thad J. 10 1900 (has links)
International Telemetering Conference Proceedings / October 28-31, 1996 / Town and Country Hotel and Convention Center, San Diego, California / This paper describes a 300 Mega Bit Per Second (MBPS) Front End Processor (FEP) prototype completed in early 1993. The FEP implements a patent pending parallel frame synchronizer (frame sync) design in 12 Actel 1240 Field Programmable Gate Arrays (FPGA's). The FEP also provides (255,223) Reed-Solomon (RS) decoding and a High Performance Parallel Interface (HIPPI) output interface. The recent introduction of large RAM based FPGA's allows greater high speed data processing integration and flexibility to be achieved. A proposed FEP implementation based on Altera 10K50 FPGA's is described. This design can be implemented on a single slot 6U VME module, and includes a PCI Mezzanine Card (PMC) for a commercial Fibre Channel or Asynchronous Transfer Mode (ATM) output interface module. Concepts for implementation of (255,223) RS and Landsat 7 Bose-Chaudhuri-Hocquenghem (BCH) decoding in FPGA's are also presented. The paper concludes with a summary of the advantages of high speed data processing in FPGA's over Application Specific Integrated Circuit (ASIC) based approaches. Other potential data processing applications are also discussed.
190

Sensorless control of brushless synchronous starter generator including sandstill and low speed region for aircraft application / Commande sans capteurs mécaniques de la machine synchrone à trois étages à faible vitesse pour une application aéronautique

Maalouf Haddad, Amira 03 March 2011 (has links)
In More Electric Aircraft, different power system activities are attributed to electrical means such as the start-up of the main engine. In this context, the study of the sensorless control of the Brushless Synchronous Starter Generator (BSSG) that is used to electrically start the main engine is revealed to be a very interesting issue. For long time, the elimination of the mechanical sensor was highly recommended for reliability, cost, weight, integration issues.Hence, this work aims to transpose the results obtained in the research area to an avionic testbench. It presents an adaptive sensorless technique to use when electrically starting the main engine of the aircraft. This is achieved by elaborating three different methods selected depending on the speed of the machine and based on the :- injection of a high frequency signal- use of the back-emf of the Permanent Magnet Generator (PMG)- use of the extended Kalman Filter EKFIn this work, it is shown that the …first method gives good position estimation results from standstill up to 8% of the rated speed. Then, the back-emfs of the PMG are used to detect the position of the BSSG when the speed exceeds the 8% of the rated speed. Good results are observed with this method at medium and high speed.For redundancy reasons, the EKF was also used in this work. Thus, the estimated position can be delivered via two different estimation algorithms in medium and high speed region.The implementation of the algorithm was achieved on an FPGA board since the latter can ensure a very tiny execution time. The fastness of the treatment ensures quasi-instantaneous position estimation and does not practically introduce any phase lag in the position estimation. / Aujourd'hui, l'aviation est en train de vivre des évolutions technologiques concernant surtout l'attribution de différentes fonctionnalités aux équipements électriques et ceci au détriment d'équipements hydrauliques et mécaniques assurant les mêmes fonctionnalités.Dans le cadre de l'avion plus électrique, le démarrage électrique sans capteurs mécaniques de la turbine de l'avion préoccupe les avionneurs de nos jours. Les problèmes introduits par ce capteur ont été identifiés : problèmes de coût et de poids, problèmes de fiabilité et d'intégration.Ce travail présente alors une commande sans capteurs pour la machine synchrone à trois étages à utiliser durant le démarrage électrique de l'avion. Ceci est réalisé avec trois méthodes de détection de la position selon la vitesse de rotation, basées sur :- l'injection d'un signal à haute fréquence- l'utilisation d'un filtre de Kalman étendu FKE- les fém. du PMG (Permanent Magnet Generator) La première méthode donne de bons résultats d'estimation depuis l'arrêt jusqu'à 8% de la vitesse nominale de la machine. Au-delà de cette vitesse, es valeurs des fém. du PMG deviennent assez élevées pour être utilisées dans l'estimation de la position. De bons résultats sont obtenus à moyenne et haute vitesse.Pour des questions de redondance, le FKE est aussi utilisé. Ainsi, la position estimée peut être fournie par l'un des deux algorithmes à moyenne et haute vitesse.L'implémentation de ces algorithmes est réalisée via une carte FPGA étant donné que celui-ci garantit un temps d'exécution. La rapidité de traitement garantit une estimation de la position quasi-instantanée et donc n'introduit pratiquement pas des retards dans l'estimation.

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