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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.
161

Modeling, Advance Control, and Grid Integration of Large-Scale DFIG-Based Wind Turbines during Normal and Fault Ride-Through Conditions

Alsmadi, Yazan M. 14 October 2015 (has links)
No description available.
162

Investigation of Nonlinear Control Strategies Using GPS Simulator And Spacecraft Attitude Control Simulator

Kowalchuk, Scott Allen 17 December 2007 (has links)
In this dissertation, we discuss the Distributed Spacecraft Attitude Control System Simulator (DSACSS) testbed developed at Virginia Polytechnic Institute and State University for the purpose of investigating various control techniques for single and multiple spacecraft. DSACSS is comprised of two independent hardware-in-the-loop simulators and one software spacecraft simulator. The two hardware-in-the-loop spacecraft simulators have similar subsystems as flight-ready spacecraft (e.g. command and data handling; communications; attitude determination and control; power; payload; and guidance and navigation). The DSACSS framework is a flexible testbed for investigating a variety of spacecraft control techniques, especially control scenarios involving coupled attitude and orbital motion. The attitude hardware simulators along with numerical simulations assist in the development and evaluation of Lyapunov based asymptotically stable, nonlinear attitude controllers with three reaction wheels as the control device. The angular rate controller successfully tracks a time varying attitude trajectory. The Modified Rodrigues Parmater (MRP) attitude controller results in successfully tracking the angular rates and MRP attitude vector for a time-varying attitude trajectory. The attitude controllers successfully track the reference attitude in real-time with hardware similar to flight-ready spacecraft. Numerical simulations and the attitude hardware simulators assist in the development and evaluation of a robust, asymptotically stable, nonlinear attitude controller with three reaction wheels as the actuator for attitude control. The MRPs are chosen to represent the attitude in the development of the controller. The robust spacecraft attitude controller successfully tracks a time-varying reference attitude trajectory while bounding system uncertainties. The results of a Global Positioning System (GPS) hardware-in-the-loop simulation of two spacecraft flying in formation are presented. The simulations involve a chief spacecraft in a low Earth orbit (LEO), while a deputy spacecraft maintains an orbit position relative to the chief spacecraft. In order to maintain the formation an orbit correction maneuver (OCM) for the deputy spacecraft is required. The control of the OCM is accomplished using a classical orbital element (COE) feedback controller and simulating continual impulsive thrusting for the deputy spacecraft. The COE controller requires the relative position of the six orbital elements. The deputy communicates with the chief spacecraft to obtain the current orbit position of the chief spacecraft, which is determined by a numerical orbit propagator. The position of the deputy spacecraft is determined from a GPS receiver that is connected to a GPS hardware-in-the-loop simulator. The GPS simulator creates a radio frequency (RF) signal based on a simulated trajectory, which results in the GPS receiver calculating the navigation solution for the simulated trajectory. From the relative positions of the spacecraft the COE controller calculates the OCM for the deputy spacecraft. The formation flying simulation successfully demonstrates the closed-loop hardware-in-the-loop GPS simulator. This dissertation focuses on the development of the DSACSS facility including the development and implementation of a closed-loop GPS simulator and evaluation of nonlinear feedback attitude and orbit control laws using real-time hardware-in-the-loop simulators. / Ph. D.
163

Probing-based testing for SCADA systems : A novel method for hardware-in-the-loop integration testing of SCADA systems / Probbaserad testning av SCADAsystem : En ny metodik för integrationstestning av SCADAsystem på verklig hårdvara

Heddini, August January 2024 (has links)
Integration testing in software refers to a type of tests where system components are tested as a group for the purpose of verifying their interfaces. It is an important phase in system testing which aims at verifying the compliance of the system with specified functional requirements and the elimination of errors in the interaction of system components. Often integration testing is performed on complex systems with additional requirements for the testing approaches wherein the hardware limitations and time delays need to be taken into account. The testing of such systems is commonly performed through hardware-in-the-loop (HIL) tests. Despite the advances in both integration testing and HIL testing, combining the two for complex systems is still a challenging issue requiring a new set of potential solutions. In this thesis work we propose a new solution approach for HIL integration testing of Supervisory Control and Data Acquisition (SCADA) systems which does not require any simulation of the system under test. The solution presented in this thesis is based on the utilization of probes which are deployed to select component interfaces and through which real-time, inter-component communication can be observed without interference. The feasibility of the proposed approach is evaluated by applying it to a proof-of-concept test of the SCADA control system for a wave-energy converter in development by the thesis host company CorPower Ocean. In the results chapter we further discuss the architectural solution of the probing-based approach and provide further implementation details. Our conclusion is that the proposed approach corresponds to a promising, light-weight, and modular testing solution that can be used to perform live software integration tests of a fully connected system with little to no interference on its operation. / Inom mjukvarubranschen är integrationstester en typ av testning där grupper av systemkomponenter testas tillsammans för att säkerställa funktionaliteten av deras gränssnitt. Det är en viktig fas inom systemtestning som försäkrar att systemet som helhet uppfyller designkraven samt som minimerar felrisken i interaktioner mellan delkomponenter. Integrationstester utförs ofta på komplexa system där testningen i sig har ytterligare krav som inskränker metodvalet, till exempel då hänsyn behöver tas till hårdvarubegränsningar eller timing. Ofta genomförs testningen av sådana system med så kallade hardware-in-the-loop-tester (HIL). Trots modern utveckling inom både integrations- och HIL-testning är det fortfarande mycket utmanande att kombinera båda metoderna för komplexa system och nya lösningar behöver utvecklas och utvärderas. I denna avhandling föreslås en ny sådan lösning för HIL-testning av Supervisory Control and Data Acquisition (SCADA) -kontrollsystem som inte kräver att någon del av systemet simuleras under testernas utförande. Lösningen är baseras på användandet av mjukvarusonder som sätts in vid utvalda komponentgränssnitt och som i realtid kan observera interkomponentkommunikation utan störningspåverkan på komponenterna i sig. Den beskrivna lösningen utvärderades genom att utföra en praktisk konceptvalidering mot SCADAkontrollsystemet för avhandlingens värdbolag CorPower Oceans vågenergigenerator. I avhandlingen beskrivs även den arkitekturella lösning som krävdes för att genomföra sonderingsbaserad testning på ett reellt system samt implementationsdetaljer för konceptvalideringen. Slutsatsen är att den föreslagna lösningen beskriver en lovande och modulär testningsmetodik som kan användas för att genomföra mjukvaruintegrationstester av komplexa, sammankopplade system i realtid, utan simuleringar och utan betydande störningspåverkan på systemets operation
164

Modeling, Simulation, and Injection of Camera Images/Video to Automotive Embedded ECU : Image Injection Solution for Hardware-in-the-Loop Testing

Lind, Anton January 2023 (has links)
Testing, verification and validation of sensors, components and systems is vital in the early-stage development of new cars with computer-in-the-car architecture. This can be done with the help of the existing technique, hardware-in-the-loop (HIL) testing which, in the close loop testing case, consists of four main parts: Real-Time Simulation Platform, Sensor Simulation PC, Interface Unit (IU), and unit under test which is, for instance, a Vehicle Computing Unit (VCU). The purpose of this degree project is to research and develop a proof of concept for in-house development of an image injection solution (IIS) on the IU in the HIL testing environment. A proof of concept could confirm that editing, customizing, and having full control of the IU is a possibility. This project was initiated by Volvo Cars to optimize the use of the HIL testing environment currently available, making the environment more changeable and controllable while the IIS remains a static system. The IU is an MPSoC/FPGA based design that uses primarily Xilinx hardware and software (Vivado/Vitis) to achieve the necessary requirements for image injection in the HIL testing environment. It consists of three stages in series: input, image processing, and output. The whole project was divided in three parts based on the three stages and carried out at Volvo Cars in cooperation by three students, respectively. The author of this thesis was responsible for the output stage, where the main goal was to find a solution for converting, preferably, AXI4 RAW12 image data into data on CSI2 format. This CSI2 data can then be used as input to serializers, which in turn transmit the data via fiber-optic cable on GMSL2 format to the VCU. Associated with the output stage, extensive simulations and hardware tests have been done on a preliminary solution that partially worked on the hardware, producing signals in parts of the design that could be read and analyzed. However, a final definite solution that fully functions on the hardware has not been found, because the work is at the initial phase of an advanced and very complex project. Presented in this thesis is: important theory regarding, for example, protocols CSI2, AXI4, GMSL2, etc., appropriate hardware selection for an IIS in HIL (FPGA, MPSoC, FMC, etc.), simulations of AXI4 and CSI2 signals, comparisons of those simulations with the hardware signals of an implemented design, and more. The outcome was heavily dependent on getting a certain hardware (TEF0010) to transmit the GMSL2 data. Since the wrong card was provided, this was the main problem that hindered the thesis from reaching a fully functioning implementation. However, these results provide a solid foundation for future work related to image injection in a HIL environment.
165

Нови поступак за развој управљачких склопова енергетске електронике заснован на емулацији у стварном времену / Novi postupak za razvoj upravljačkih sklopova energetske elektronike zasnovan na emulaciji u stvarnom vremenu / New real time emulation based procedure for Power Electronics controllersdevelopment

Vekić Marko 14 February 2014 (has links)
<p>У тези je предложен поступак развоја управљачких склопова енергетске<br />електронике заснован на технологији Hardware In the Loop. Подробно је<br />описан предложени емулатор са нагласком на специфичном<br />моделовању погодном за извршење у стварном времену што је<br />предуслов веродостојности. Сама веродостојност је проверена<br />поређењем резултата са симулацијом, као и са измереним резултатима<br />у неколико стварних погона. Затим је поступак развоја управљачких<br />склопова подробно објашњен на примеру развоја и испитивања једног<br />новог контролног алгоритма за повезивање синхроног генератора на<br />електричну мрежу.</p> / <p>U tezi je predložen postupak razvoja upravljačkih sklopova energetske<br />elektronike zasnovan na tehnologiji Hardware In the Loop. Podrobno je<br />opisan predloženi emulator sa naglaskom na specifičnom<br />modelovanju pogodnom za izvršenje u stvarnom vremenu što je<br />preduslov verodostojnosti. Sama verodostojnost je proverena<br />poređenjem rezultata sa simulacijom, kao i sa izmerenim rezultatima<br />u nekoliko stvarnih pogona. Zatim je postupak razvoja upravljačkih<br />sklopova podrobno objašnjen na primeru razvoja i ispitivanja jednog<br />novog kontrolnog algoritma za povezivanje sinhronog generatora na<br />električnu mrežu.</p> / <p>This paper proposes development of Power Electronics controllers based on<br />the Hardware In the Loop technology. Proposed emulator is describied in<br />detail where emphasis was set on specific methods of modeling which is<br />suitable for real time emulations in order to obtain emulation faithfulness.<br />Fidelity itself was checked through comparison with off-line simulations and<br />results of real drives. Procedure of controllers development was presented<br />through development and testing of one new control algorithm for connection<br />of the permanent magnet synchronous generator to the electrical grid.</p>
166

Hardware-in-the-loop based-real-time simulations in robotic additive manufacturing

Singh, Gurtej, Hajian Foroushany, Ali January 2022 (has links)
Hardware-in-the-loop (HiL) is a concept for testing physical equipment by connecting itto a mathematical representation (model) of the physical process. HiL-testing reduces thecost and saves time before testing the physical equipment (hardware) on the real (physical)process. The physical process chosen for this study is wire+arc additive manufacturing(WAAM), an advanced additive manufacturing (AM) technology that deposits metalbased material layer-by-layer. In this study, simulations of the robot path are carried outwhile the physical robot performs a physical process (additive manufacturing). In robotadditive manufacturing, the desired CAD model is currently sliced down into layers usingslicer software, and the layers are then translated into a path. The robot then moves alongthe path of these pre-defined layers to produce a three-dimensional structure. The heightof the produced structures and desired CAD models have deviations because of processinstabilities and temperature variations among other factors. The robot path should beupdated every time a layer is printed to compensate for the height differences. This isachieved by parametrizing the CAD model, i.e., the CAD model of the structure to beprinted is replaced by a mathematical equation (model). In this study, the mathematicalmodel is updated for each layer in real-time with feedback data from sensors that monitorthe additive manufacturing process. The concept of updating a mathematical model andexecuting it in real-time is called real-time simulation (RTS). In this study, a HiL-basedreal-time simulation setup has been developed, which predicts the required printing layerheight and the number of layers (based upon the latest feedback data from the monitoringsensors), and the required height of the structure. By combining hardware and software,a cyber-physical system has been created, enabling the transition from automation toautonomous robotics and contributing to Industry 4.0.
167

Development of a pipeline to allow continuous development of software onto hardware : Implementation on a Raspberry Pi to simulate a physical pedal using the Hardware In the Loop method / Utveckling av en pipeline för att ge upphov till kontinuerligt utvecklande av mjukvara på hårdvara : Implementation på en Raspberry Pi för att simulera en fysisk pedal genom användandet av Hardware In the Loop-metoden

Ryd, Jonatan, Persson, Jeffrey January 2021 (has links)
Saab want to examine Hardware In the Loop method as a concept, and how an infrastructure of Hardware In the Loop would look like. Hardware In the Loop is based upon continuously testing hardware, which is simulated. The software Saab wants to use for the Hardware In the Loop method is Jenkins, which is a Continuous Integration, and Continuous Delivery tool. To simulate the hardware, they want to examine the use of an Application Programming Interface between a Raspberry Pi, and the programming language Robot Framework. The reason Saab wants this examined, is because they believe that this method can improve the rate of testing, the quality of the tests, and thereby the quality of their products.The theory behind Hardware In the Loop, Continuous Integration, and Continuous Delivery will be explained in this thesis. The Hardware In the Loop method was implemented upon the Continuous Integration and Continuous Delivery tool Jenkins. An Application Programming Interface between the General Purpose Input/Output pins on a Raspberry Pi and Robot Framework, was developed. With these implementations done, the Hardware In the Loop method was successfully integrated, where a Raspberry Pi was used to simulate the hardware. / Saab vill undersöka metoden Hardware In the Loop som ett koncept, dessutom hur en infrastruktur av Hardware In the Loop skulle se ut. Hardware In the Loop baseras på att kontinuerligt testa hårdvara som är simulerad. Mjukvaran Saab vill använda sig av för Hardware In the Loop metoden är Jenkins, vilket är ett Continuous Integration och Continuous Delivery verktyg. För attsimulera hårdvaran vill Saab undersöka användningen av ett Application Programming Interface mellan en Raspberry Pi och programmeringsspråket Robot Framework. Anledning till att Saab vill undersöka allt det här, är för att de tror att det kan förbättra frekvensen av testning och kvaliteten av testning, vilket skulle leda till en förbättring av deras produkter. Teorin bakom Hardware In the Loop, Continuous Integration och Continuous Delivery kommer att förklaras i den här rapporten. Hardware In the Loop metoden blev implementerad med Continuous Integration och Continuous Delivery verktyget Jenkins. Ett Application Programming Interface mellan General Purpose Input/output pinnarna på en Raspberry Pi och Robot Framework blev utvecklat. Med de här implementationerna utförda, så blev Hardware Inthe Loop metoden slutligen integrerat, där Raspberry Pis användes för att simulera hårdvaran.
168

Eco-Driving of Connected and Automated Vehicles (CAVs)

Kavas Torris, Ozgenur 23 September 2022 (has links)
No description available.

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