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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.
71

A Hardware-in-the-Loop Test Platform for Planetary Rovers

Yue, Bonnie January 2011 (has links)
Hardware-in-the-Loop (HIL) test platform for planetary rovers was designed, fabricated and tested in the present work. The ability for planetary rover designers and mission planners to estimate the rover’s performance through software simulation is crucial. HIL testing can further the benefits of software simulations by allowing designers to incorporate hardware components within traditionally pure software simulations. This provides more accurate performance results without having access to all hardware components, as would be required for a full prototype testing. The test platform is designed with complete modularity such that different types of tests can be performed for varying types of planetary rovers and in different environments. For demonstrating the operation of the test platform, however, the power system operation of a solar powered rover was examined. The system consists of solar panels, a solar charge controller, a battery, a DC/DC converter, a DC motor and a flywheel. In addition, a lighting system was designed to simulate the solar radiation conditions solar panels would experience throughout a typical day. On the software side, a library of component models was developed within MapleSim and model parameters were tuned to match the hardware on the test bench. A program was developed for real-time simulations within Labview allowing communication between hardware components and software models. This program consists of all the component models, hardware controls and data acquisitioning. The GUI of this program allows users to select which component is to be tested and which component is to be simulated, change model parameters as well as see real time sensor measurements for each component. A signal scaling technique based on non-dimensionalization is also presented, which can be used in an HIL application for obtain scaling factors to ensure dynamic similarity between two systems. A demonstration of power estimation was performed using the pure software model simulations as well as the pure hardware testing. Hardware components were then added into the software simulation progressively with results showing better accuracy as hardware is added. The rover’s power flow was also estimated under different load conditions and seasonal variation. These simulations clearly demonstrate the effectiveness of an HIL platform for testing a rover’s hardware performance.
72

Design and Hardware-in-the-Loop Testing of Optimal Controllers for Hybrid Electric Powertrains

Sharif Razavian, Reza January 2012 (has links)
The main objective of this research is the development of a flexible test-bench for evaluation of hybrid electric powertrain controllers. As a case study, a real-time near-optimal powertrain controller for a series hybrid electric vehicle (HEV) has been designed and tests. The designed controller, like many other optimal controllers, is based on a simple model. This control-oriented model aims to be as simple as possible in order to minimize the controller computational effort. However, a simple model may not be able to capture the vehicle's dynamics accurately, and the designed controller may fail to deliver the anticipated behavior. Therefore, it is crucial that the controller be tested in a realistic environment. To evaluate the performance of the designed model-based controller, it is first applied to a high-fidelity series HEV model that includes physics-based component models and low-level controllers. After successfully passing this model-in-the-loop test, the controller is programmed into a rapid-prototyping controller unit for hardware-in-the-loop simulations. This type of simulation is mostly intended to consider controller computational resources, as well as the communication issues between the controller and the plant (model solver). As the battery pack is one of the most critical components in a hybrid electric powertrain, the component-in-the-loop simulation setup is used to include a physical battery in the simulations in order to further enhance simulation accuracy. Finally, the driver-in-the-loop setup enables us to receive the inputs from a human driver instead of a fixed drive cycle, which allows us to study the effects of the unpredictable driver behavior. The developed powertrain controller itself is a real-time, drive cycle-independent controller for a series HEV, and is designed using a control-oriented model and Pontryagin's Minimum Principle. Like other proposed controllers in the literature, this controller still requires some information about future driving conditions; however, the amount of information is reduced. Although the controller design procedure is based on a series HEV with NiMH battery as the electric energy storage, the same procedure can be used to obtain the supervisory controller for a series HEV with an ultra-capacitor. By testing the designed optimal controller with the prescribed simulation setups, it is shown that the controller can ensure optimal behavior of the powertrain, as the dominant system behavior is very close to what is being predicted by the control-oriented model. It is also shown that the controller is able to handle small uncertainties in the driver behavior.
73

Nonlinear tracking of natural mechanical systems for HWIL simulation

Martin, Justin N. January 2007 (has links) (PDF)
Thesis (M.S.)--Auburn University, 2007. / Abstract. Includes bibliographic references (ℓ. 94-95)
74

Fuzzy Logic Based Driving Pattern Recognition for Hybrid Electric Vehicle Energy Management

January 2015 (has links)
abstract: For years the automotive industry has been shifting towards hybridization and electrification of conventional powertrains due to increase in fossil fuel cost and environmental impact due heavy emission of Green House Gases (GHG) and various pollutants into atmosphere by combustion engine powered vehicles. Hybrid Electric Vehicles (HEV) have proved to achieve superior fuel economy and reduced emissions. Supervisory control strategies determining the power split among various onboard power sources are evolving with time, providing better fuel economies. With increasing complexity of control systems driving HEV’s, mathematical modeling and simulation tools have become extremely advanced and have derived whole industry into adopting Model Based Design (MBD) and Hardware-in-the-loop (HIL) techniques to validate the performance of HEV systems in real world. This report will present a systematic mythology where MBD techniques are used to develop hybrid powertrain, supervisory control strategies and control systems. To validate the effectiveness of various energy management strategies for HEV energy management in a real world scenario, Conventional rule-based power split strategies are compared against advanced Equivalent Consumption Minimization Strategy (ECMS), in software and HIL environment. Since effective utilization of the fuel reduction potential of a HEV powertrain requires a careful design of the energy management control methodology, an advanced ECMS strategy involving implementation with Fuzzy Logic to reduce computational overload has been proposed. Conventional real-time implementation of ECMS based strategy is difficult due to the involvement of heavy computation. Methods like Fuzzy Logic based estimation can be used to reduce this computational overload. Real-time energy management is obtained by adding a Fuzzy Logic based on-the-fly algorithm for the estimation of driving profile and adaptive equivalent consumption minimization strategy (A-ECMS) framework. The control strategy is implemented to function without any prior knowledge of the future driving conditions. The idea is to periodically refresh the energy management strategy according to the estimated driving pattern, so that the Battery State of Charge (SOC) is maintained within the boundaries and the equivalent fuel consumption is minimized. The performance of the presented Fuzzy Logic based adaptive control strategy utilizing driving pattern recognition is benchmarked using a Dynamic Programming based global optimization approach. / Dissertation/Thesis / Masters Thesis Engineering 2015
75

Testing degradation in a complex vehicle electrical system using Hardware-In-the-Loop

Bergkvist, Johannes January 2009 (has links)
Functionality in the automotive industry is becoming more complex, withcomplex communication networks between control systems. Information isshared among many control systems and extensive testing ensures high quality. Degradations testing, that has the objective to test functionality with some faultpresent, is performed on single control systems, but is not frequently performed on the entire electrical system. There is a wish for testing degradation automatically on the complete electrical system in a so called Hardware-In-the-Loop laboratory. A technique is needed to perform these tests on a regular basis.Problems with testing degradation in complex communication systems will bedescribed. Methods and solutions to tackle these problems are suggested, thatfinally end up with two independent test strategies. One strategy is suited to test degradation on new functionality. The other strategy is to investigate effects in the entire electrical system. Both strategies have been implemented in a Hardware-In-the-Loop laboratory and evaluated.
76

Hardware in the Loop (HIL) Rig Design and Electrical Architecture

Mahmud, Akib January 2017 (has links)
Different types of machines are tested utilizing so called Hardware In the Loop simulation. To perform HIL-simulation a rig is used consisting of different types of hardware and software. Some of the hardware that are used during a simulation is located inside an EMS box. The box has not been properly updated since 2004, no documentation of changes has been made and often many errors occurs during simulations due to the lack of traceability. During this project a new structure of the EMS box has been designed with modifications to eliminate existing problems, prevent similar problems to occur in the future and improve the usability of the system. A simulation was performed on the camshaft to test if there were any improvements. Most issues were solved but there were one problem that remained. Some noises existed and were rooted in the old box which undeniably remained in the new one.
77

Simulation énergétique flexible d’un carrousel de métros basée sur la représentation énergétique macroscopique / Flexible energetic simulation of a subway carrousel based on energetic macroscopic representation

Mayet, Clément 24 March 2016 (has links)
La sobriété énergétique des systèmes de transport est primordiale afin de limiter leur impact environnemental. Ainsi les transports en communs électriques, tels que les métros ou tramways, sont fortement sollicités dans les zones urbaines. Diverses solutions innovantes sont apparues récemment afin d’accroître d’avantage leur efficacité énergétique (systèmes de stockage d’énergie, stations d’alimentation réversibles, etc.). Cependant, au vu de la complexité des études de dimensionnement et d’optimisation de ces systèmes, les outils de simulation numérique sont devenus indispensables. Or, ces outils sont particulièrement délicats à développer en raison des non-linéarités (non-réversibilité des stations d’alimentation), des non-stationnarités (mouvement des rames), et des fortes interactions énergétiques qui existent au sein des systèmes ferroviaires. Cette thèse propose alors un nouvel outil de simulation de carrousel de métros basé sur le formalisme REM (Représentation Energétique Macroscopique). Ce formalisme a pour volonté de structurer les modèles mis en jeux suivant les propriétés énergétiques du système. Il conduit à des approches de simulation « forward » avec un usage exclusif de la causalité intégrale. De ce fait, le programme de simulation proposé est issu d’une approche innovante et permet d’avoir un nouveau regard sur le système de carrousel de métros. Ces approches permettent notamment d’accroitre la flexibilité du programme de simulation tout en garantissant des résultats de simulation physiques. De plus, cette thèse a une volonté affichée de valider expérimentalement l’ensemble des modèles développés. / Transportation systems have to be efficient in terms of energy in order to limit their environmental impact. Electric public transportation, such as subways or tramways, is thus strongly requested in urban areas. Various innovative solutions have emerged recently to increase their energy efficiency (energy storage systems, reversible traction power substations, etc.). However, due to the complexity of the development and optimization of such systems, numerical simulation tools are essential. Nevertheless, simulators of railway systems are particularly delicate to develop due to non-linearity (non-reversibility of traction power substations), non-stationary (displacement of trains), and multiple energetic interactions which exists within these kind of systems. This PhD thesis then proposes a new simulation tool of subway system based on EMR formalism (Energetic Macroscopic Representation). This formalism structures the models according to the energetic properties of the system. It leads to a forward simulation approach with exclusive use of the integral causality. In that way, the proposed simulation tool is stemming from an innovative approach and allows a new vision of subway systems. These approaches allow especially the increasing of the simulator flexibility and the obtaining of physical simulation results. Moreover, this PhD thesis has the particularity to experimentally validate all the developed models.
78

Software and Hardware-In-The-Loop Modeling of an Audio Watermarking Algorithm

Zarate Orozco, Ismael 12 1900 (has links)
Due to the accelerated growth in digital music distribution, it becomes easy to modify, intercept, and distribute material illegally. To overcome the urgent need for copyright protection against piracy, several audio watermarking schemes have been proposed and implemented. These digital audio watermarking schemes have the purpose of embedding inaudible information within the host file to cover copyright and authentication issues. This thesis proposes an audio watermarking model using MATLAB® and Simulink® software for 1K and 2K fast Fourier transform (FFT) lengths. The watermark insertion process is performed in the frequency domain to guarantee the imperceptibility of the watermark to the human auditory system. Additionally, the proposed audio watermarking model was implemented in a Cyclone® II FPGA device from Altera® using the Altera® DSP Builder tool and MATLAB/Simulink® software. To evaluate the performance of the proposed audio watermarking scheme, effectiveness and fidelity performance tests were conducted for the proposed software and hardware-in-the-loop based audio watermarking model.
79

HIL simulace manipulátorů nebo stroje / HIL simulation of manipulators or machines

Dočekal, Martin January 2021 (has links)
The diploma thesis deals with HIL simulation (hardware in the loop). The thesis contains a manipulator created in the virtual software V-REP. The connection of real inputs and virtual outputs of the machine is realized by the microcontroller Arduino UNO. The first task deals with the control of the manipulator using the joystick PS2. The second task is a separate control of the robot using an microcontroller Arduino UNO. The resulting connection can be modified in the furher and the interface modified. The work will be used for educational purposes.
80

Multi-operated HIL Test Bench for Testing Underwater Robot’s Buoyancy Variation System

Gafurov, Salimzhan A., Reshetov, Viktor M., Salmina, Vera A., Handroos, Heikki January 2016 (has links)
Nowadays underwater gliders have become to play a vital role in ocean exploration and allow to obtain the valuable information about underwater environment. The traditional approach to the development of such vehicles requires a thorough design of each subsystem and conducting a number of expensive full scale tests for validation the accuracy of connections between these subsystems. However, present requirements to cost-effective development of underwater vehicles need the development of a reliable sampling and testing platform that allows the conducting a preliminary design of components and systems (hardware and software) of the vehicle, its simulation and finally testing and verification of missions. This paper describes the development of the HIL test bench for underwater applications. Paper discuses some advantages of HIL methodology provides a brief overview of buoyancy variation systems. In this paper we focused on hydraulic part of the developed test bench and its architecture, environment and tools. Some obtained results of several buoyancy variation systems testing are described in this paper. These results have allowed us to estimate the most efficient design of the buoyancy variation system. The main contribution of this work is to present a powerful tool for engineers to find hidden errors in underwater gliders development process and to improve the integration between glider’s subsystems by gaining insights into their operation and dynamics.

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