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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.
1

Pulsed Active Steering Hardware in the Loop Experiment

Abdel-Rahman, Akram 25 September 2009 (has links)
Active safety vehicle systems are continuously being researched to make vehicles safer to drive. Active steering is a new active safety system that involves controlling the vehicle steering angle during the vehicle's loss of stability. The steering signal, which an active steering system intervenes with, is brought to study in this thesis. Using a pulsed signal instead of a constant signal as the output of an active steering system arises new areas to study. This thesis focuses on the effect that the different pulse parameters have on the yaw and roll dynamics of a passenger vehicle. The parameters of a pulse consist of its frequency, amplitude, and pattern. Simulations were done with different vehicle models in different simulation softwares to assess the effect that each of the pulse parameters has on the vehicle dynamics. These simulation softwares include DynaFlexPro, Matlab/Simulink and Adams/Car. In addition, a whole test bed was designed and assembled to carry out Hardware-In-the-Loop (HIL) simulation experiments involving active steering systems. The test bed was used to firstly validate the results obtained from the simulations, and secondly to assess the applicability of a pulsed active steering system. Conclusions of the obtained results as well as future work are mentioned at the end of this thesis.
2

Pulsed Active Steering Hardware in the Loop Experiment

Abdel-Rahman, Akram 25 September 2009 (has links)
Active safety vehicle systems are continuously being researched to make vehicles safer to drive. Active steering is a new active safety system that involves controlling the vehicle steering angle during the vehicle's loss of stability. The steering signal, which an active steering system intervenes with, is brought to study in this thesis. Using a pulsed signal instead of a constant signal as the output of an active steering system arises new areas to study. This thesis focuses on the effect that the different pulse parameters have on the yaw and roll dynamics of a passenger vehicle. The parameters of a pulse consist of its frequency, amplitude, and pattern. Simulations were done with different vehicle models in different simulation softwares to assess the effect that each of the pulse parameters has on the vehicle dynamics. These simulation softwares include DynaFlexPro, Matlab/Simulink and Adams/Car. In addition, a whole test bed was designed and assembled to carry out Hardware-In-the-Loop (HIL) simulation experiments involving active steering systems. The test bed was used to firstly validate the results obtained from the simulations, and secondly to assess the applicability of a pulsed active steering system. Conclusions of the obtained results as well as future work are mentioned at the end of this thesis.
3

Air charge system emulation for diesel engine

Zhang, Kai January 2010 (has links)
The work presented in this thesis details a novel engine evaluation approach utilising real-time simulation and advanced engine testing systems for general applicability to new generations of air charging systems. A novel engine air charging system including a charge air handling unit (CAHU) has been developed which is connected to an engine to emulate advanced boosting system conditions. Significant analytical and development work has focused on generating a real-time turbocharger model such that the CAHU can be effectively controlled to emulate the turbocharger performance under both steady and pulsating conditions. Experimental work was carried out to evaluate this new engine air charge testing system against a production turbocharged baseline engine. The accuracies with respect to the boost pressure, turbocharger speed, mass air flow, and fuel consumption in the steady state tests are above 95%, and the level of confidence for the engine back pressure is approximately 90%. The difference of turbocharger speed between the steady turbocharger model and the pulsation model is also identified. In engine transient tests, the boost pressure and engine torque have shown fast response characteristics similar to that of the baseline engine. While general transient trends were achieved, some issues were identified with the high speed control of the CAHU interacting with the dSPACE real time turbocharger model. It is proposed that future improvement can be achieved via applying new control algorithms to improve the accuracy and tracking the CAHU control without increasing the system instabilities.
4

Modellering och simulering av hydraulik för användning i hardware-in-the-loop / Modeling and simulation of hydraulics for use in hardware-in-the-loop

Israelsson, Erik January 2012 (has links)
Modeling and simulation is growing ever more important in the development of new products. This thesis describes the use of Hopsan for hydraulic modeling and its use in conjunction with Simulink with the intent of using the model in a hardware-in-the-loop setup. A sensor layer has been created in Simulink to emulate all the internal sensors in a modern forklift. The details of using legacy C-code instead of a hardware MCU for a fully simulated environment, software-in-the-loop has been outlined. There are two major routes one can follow implementing software-in-the-loop, exporting the C-functions to CAPL via a export layer or creating an s-function in Simulink. Of the two the export layer method is the most promising since it is easier handling different execution times in CAPL than in Simulink.
5

Modeling and Simulation of a Hybrid Electric Vessel

Jaster, Tiffany 03 January 2014 (has links)
A proposed hybrid electric marine vehicle was modeled in MATLAB Simulink and SimPowerSystems. Models for each of the individual propulsion components were developed and incorporated into a complete hybrid electric propulsion model. A vessel resistance model was created to support vessel performance and energy requirement evaluation. The model incorporates data based on the ship principal parameters and hull form. A rule-based supervisory controller for the proposed vessel was constructed. It is an amalgamation of control strategies of three vehicle architectures: electric vehicle, fuel cell electric vehicle, and hybrid electric vehicle (HEV). The complete model of the hybrid electric propulsion, control, and resistance subsystems was simulated on a dSPACE hardware-in-the-loop platform. For each simulation, the energy storage system (ESS) state of charge, station keeping/cruising mode, HEV assist, Beaufort number, current speed, true wind angle, and hotel load were specified. From the simulations, it was demonstrated that using a 30% ESS assisted HEV mode results in reduced emissions and fuel consumption as compared to a conventional vessel powertrain mode, supporting the case for plug-in hybrid electric vessels. A larger capacity ESS has the potential to reduce emissions and fuel consumption further, depending on ship usage. The basic rule-based supervisory controller proved functional for facilitating adequate power flows; however, further development is needed to improve efficiency and the mode selection process. / Graduate / 0548
6

Implementation of a Hardware-in-the-Loop System Using Scale Model Hardware for Hybrid Electric Vehicle Development

Janczak, John 27 July 2007 (has links)
Hardware-in-a-loop (HIL) testing and simulation for components and control strategies can reduce both time and cost of development. HIL testing focuses on one component or control system rather than the entire vehicle. The rest of the system is simulated by computer systems which use real time data acquisition systems to read outputs and respond like the systems in the actual vehicle would respond. The hardware for the system is on a scaled-down level to save both time and money during testing. The system designed to simulate the REVLSE Equinox split parallel hybrid consists of five direct current (DC) permanent magnet motors. These motors are used in the system to test the controller software of the vehicle. Two of the motors act as power plants simulating the spark ignited Ethanol engine and the rear traction motor. These two motors are controlled by DC variable speed controllers. The other motors are used as generators to simulate the load from the belted alternator starter (BAS) and the road load on each axle. The motors on each axle are joined together mechanically using a belt and pulley system. The front and rear axle of the system are not connected to simulate the actual vehicle where the power plants are gear-reduced before they make contact with the road and therefore do not actually spin at the same speeds. The computer software and hardware used to run the HIL hybrid system is National Instruments LabView and CompactRIO. LabView provides an easy interface through which programs for the RIO can be written. The RIO gives the user the ability to measure the power into and out of different components in the system to measure the efficiency of the system. The ability to measure system efficiencies using different powertrain inputs and loading schemes is what makes the HIL system a valuable tool in control modeling for the Equinox. LabView and the RIO allow the user to optimize the control strategy with the two power plant inputs and the BAS to make sure the high voltage system stays charged and improve the overall efficiency of the vehicle without the actual vehicle. The HIL system allows other work to be done of the vehicle during the control development. During a constant axle speed test at 730 RPM with constant generator resistance, the front engine efficiency was 33.8%, the BAS efficiency was 53.0%, the rear load generator efficiency was 51.2% and the overall efficiency of the front axle was 24.0%. These results show that the system can simulate the powertrain of a hybrid vehicle and help create and validate a control scheme. / Master of Science
7

Modeling and Hardware-in-the-loop Simulations of Contactor Dynamics : Mechanics, Electromagnetics and Software / Modellering och hardware-in-the-loopsimulering av kontaktordynamik : Mekanik, elektromagnetism och mjukvara

Tjerngren, Jon January 2014 (has links)
This master thesis’s subject is to model an ABB contactor’s dynamics and to develop a hardware-in-the-loop simulation environment. The hardware-in-the-loop method utilizes computer models that are simulated in a real-time simulator. The real-time simulator is connected to hardware components. A contactor is an electrically controlled mechanical switching device and it is used in circuits where large currents can occur. In this thesis, the contactor is divided into three separate subsystems and models are developed for each of them. The three subsystems correspond to the contactor’s mechanics, electromagnetics and electronic components. Computer models are implemented in MATLAB and Simulink to realize the subsystems. The hardware part, of the hardware-in-the-loop simulations, consists of electronic parts that are not modeled. To connect the hardware part to a real-time simulator, from dSPACE, a hardware interface was constructed. This report focuses on the modeling of the mechanics and the electromagnetics as well as the software implementations. The thesis work was carried out in collaboration with another student. The focuses of his report are the modeling of the electronics and the construction of the hardware interface. Validation of the hardware-in-the-loop simulations is done by using measurements collected from a real contactor. The conclusion is that the simulations of the contactor’s behavior correspond well with a real contactor.
8

FPGA-Based Hardware-In-the-Loop Co-Simulator Platform for SystemModeler

Acevedo, Miguel January 2016 (has links)
This thesis proposes and implements a flexible platform to perform Hardware-In-the-Loop (HIL) co-simulation using a Field-Programmable-Gate-Array (FPGA). The HIL simulations are performed with SystemModeler working as a software simulator and the FPGA as the co-simulator platform for the digital hardware design. The work presented in this thesis consists of the creation of: A communication library in the host computer, a system in the FPGA that allows implementation of different digital designs with varying architectures, and an interface between the host computer and the FPGA to transmit the data. The efficiency of the proposed system is studied with the implementation of two common digital hardware designs, a PID controller and a filter. The results of the HIL simulations of those two hardware designs are used to verify the platform and measure the timing and area performance of the proposed HIL platform.
9

Contribution à l’estimation et au diagnostic robuste des piles à combustibles basse température / Contribution to robust state estimation and diagnostic of low temperature fuel cell systems

Olteanu, Severus 06 November 2015 (has links)
La thèse contribue à la conception des observateurs et au diagnostic pour les piles à combustible de type ’membrane échangeuse de protons’ en utilisant la théorie Takagi-Sugeno. Il y a trois objectifs de recherche dans cette thèse. La première est axée sur la modélisation, l’estimation et le diagnostic. Le modèle dynamique non linéaire de la pile est proposé, en considérant les composants auxiliaires. En termes d’estimation de paramètre, une approche non linéaire est développée pour concevoir des observateurs basés sur le modèle non linéaire de Takagi-Sugeno afin de parvenir à une estimation plus robuste. Les observateurs peuvent remplacer les capteurs de débit massique dont l’instrumentation est chère et difficile d’implémenter pour la mesure du débit massique. En utilisant de tels observateurs pour développer des algorithmes pour le diagnostic, la durée de vie de l’empilement de piles à combustible peut être prolongée. Une méthode simple de diagnostic basée sur un observateur PI pour l’estimation d’état et de défaut du capteur a été étudiée. Le deuxième objectif sur des algorithmes non linéaires embarqués, agit sur le potentiel de l’utilisation de systèmes embarqués de petite échelle pour des tâches complexes, réduisant ainsi le coût et la taille physique du système. Plus précisément, l’utilisation de l’approche de Takagi-Sugeno dans les applications embarquées a été développée. Différentes solutions pour les observateurs embarqués ont été fournies. Le dernier objectif concerne les tests de ces algorithmes embarqués pour des piles à combustible dans une architecture HIL, avec le logiciel professionnel AMESim et Matlab dans un environnement d’exploitation Windows. Une pile à combustible réelle a été utilisée afin de prouve l’efficacité de notre approche. / The thesis contributes to the observer and diagnosis design for Polymer Electrolyte Membrane Fuel Cells using Takagi-Sugeno theory. There are three research objectives in this thesis. First is focused on modeling, estimation and diagnostics. The dynamic nonlinear model of PEMFCs is proposed, which considers the auxiliary components. In terms of parameter estimation for PEMFCs, a nonlinear approach is developed to design observers based on the nonlinear Takagi-Sugeno model in order to achieve a more robust estimation. The observers can replace the mass flow sensors which results in getting rid of expensive and cumbersome to install instrumentation for measurement of mass flow rates. By using such observers to develop algorithms for diagnosis, the fuel cell stack’s life can be prolonged. A simple method of diagnostic based on PI observer for state and sensor fault detection has been investigated. The second topic on embedding nonlinear algorithms, acts upon the potential of using small scaled embedded systems for complex tasks, thus reducing cost and physical size of the automatic system. More precisely the use of the Takagi-Sugeno approach in embedded applications is investigated. Different solutions for embedded observers have been provided. The last topic was the testing of these embedded solutions for fuel cell system in a Hardware In the Loop architecture, based on the professional software AMESim and Matlab for a Windows operating system. A real Fuel Cell has been used in order to prove the effectiveness of our approach.
10

Cylinder-by-Cylinder Torque Model of an SI-Engine for Real-Time Applications / Cylinderindividuell Momentmodell för Realtidstillämpningar

Hashemzadeh Nayeri, Mohit January 2005 (has links)
<p>In recent years Hardware-in-the-Loop HiL, has gained more and more</p><p>popularity within the vehicle industry. This is a more cost effective research alternative, as opposed to the tests done the traditional way, since in HiL testing the idea is to test the hardware of interest, such as an electronic control unit, in a simulated (or partially simulated) environment which closely resembles the real-world environment.</p><p>This thesis is ordered by Daimler Chrysler AG and the objective of this thesis is the developing of a cylinder-by-cylinder model for the purpose of emulation of misfire in a four-stroke SI-engine. This purpose does not demand a precise modelling of the cylinder pressure but rather an adequate modelling of position and amplitude of the torque produced by each cylinder. The model should be preferebly computaionally tractable so it can be run on-line. Therefore, simplifications are made such as assuming the rule of a homogenous mixture, pressure and temperature inside the cylinder at all steps, so the pressure model can be analytical and able to cope with the real-time demand of the HiL. The model is implemented in Simulink and simulated with different sample rates and an improvement is to be seen as the sample rate is decreased.</p>

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