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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.
61

Implementação de plataforma de simulação hardware-in-the-loop ABS para aplicações didáticas. / Implementation of ABS hardware-in-the-loop simulation platform for didactic applications.

Aguinaldo Batista dos Santos Junior 18 April 2017 (has links)
A utilização de plataformas HIL (Hardware-in-the-loop) tem aumentado dentro do processo de desenvolvimento de ECU\'s em indústrias do ramo automotivo. A principal justificativa para tal aumento é a utilização da metodologia de desenvolvimento baseada em modelo, a qual integra a técnica HIL como um de seus principais pilares, possibilitando redução no tempo e custos de desenvolvimento de uma ECU. Quando aplicada a validação de sistemas de controle de freios, a simulação HIL possui vital importância, pois permite a prévia visualização de efeitos diretamente relacionados à dinâmica veicular, os quais somente podiam ser analisados através da realização de testes em pistas. No entanto, os benefícios da simulação HIL não se restringem somente as aplicações industriais. A possibilidade de análise dos efeitos produzidos por um módulo eletrônico de controle através de simulações cria um campo para a utilização da técnica HIL como uma ferramenta efetiva no ensino de sistemas eletrônicos veiculares. Neste trabalho demonstra-se a implementação de uma plataforma HIL ABS para aplicações didáticas. Esta plataforma é implementada incluindo o uso de um circuito elétrico para emulação de cargas e aquisição de sinais, de uma interface com entradas e saídas reconfiguráveis, de uma ECU ABS e de um computador de simulação, o qual executa os softwares de manipulação de dados e de simulação de dinâmica veicular. Os resultados obtidos através de simulações realizadas com a plataforma desenvolvida são comparados com resultados de testes reais, validando desta forma o modelo proposto. / The HIL (Hardware-in-the-loop) platforms utilization has increased within the development process of ECUs in the automotive industry. The main reason for this increase is the usage of the model based development methodology, which integrates the HIL technique as one of its main pillars, allowing a reduction in the time and costs of developing an ECU. When applied to the validation of brake control systems, HIL simulation has a vital importance, since it allows a prior visualization of effects directly related to the vehicle dynamics, which could only be analyzed by performing track tests. However, the benefits of HIL simulation are not only restricted to the industrial applications. The possibility of analyzing the effects produced by an electronic control module through simulations creates a field for the use of the HIL technique as an effective tool for teaching vehicular electronic systems. This work demonstrates the implementation of an ABS HIL platform for didactic applications. This platform is implemented including the usage of an electrical circuit for loads emulation and signals acquisition, an interface with reconfigurable inputs and outputs, an ABS ECU and a simulation computer, which runs the data manipulation and vehicle dynamic simulation softwares. The results obtained through the performed simulations with the developed platform are compared with actual test results, validating therefore the proposed model.
62

Emulación de un aerogenerador conectado a la red a través de un sistema experimental Back-to-Back mediante la técnica "Hardware In The Loop"

Muñoz Jadán, Alexis Yanira January 2016 (has links)
Magíster en Ciencias de la Ingeniería, Mención Eléctrica / En la actualidad, el estudio de generación de electricidad por medio del recurso eólico es de gran importancia, por presentarse como solución para disminuir la contaminación ambiental al reemplazar los sistemas eléctricos a base de generación convencional por energía limpia. También, por constituir una vía de desarrollo para la sociedad al comunicarlo con la tecnología del mundo moderno. Sin embargo, debido a las dificultades que existen para realizar investigaciones de energía eólica con generadores reales, es necesario implementar prototipos que sean capaces de emular, aerogeneradores que serán utilizados en el trabajo de laboratorio. En este trabajo, mediante la técnica Hardware in the Loop , se logra en base a datos reales, emular el comportamiento de una turbina eólica en la plataforma de desarrollo Matlab/Simulink a través del sistema embebido que constituye el conversor de potencia en configuración Back-To-Back contenido en la unidad Triphase PM5F60R. Considerando perfiles de viento de distinta variabilidad con distintos valores medios y con un nivel de detalle adecuado de ingeniería, se estudia el desempeño de los sistemas de control correspondientes al aerogenerador, como: Pitch control y el algoritmo MPPT. En los cuáles se efectúan cambios en algunos parámetros importantes que caracterizan a las turbinas eólicas tales como: inercia, radio del aspa, curva aerodinámica, entre otros. Por otro lado, por medio de estrategias de control de corriente, basadas en múltiples controladores resonantes y amortiguamiento activo se logra compensar las resonancias causadas por los filtros LCL, inyectar corrientes con baja distorsión armónica y entregar potencia activa y reactiva variable a la red. Es así que, en este trabajo se identifican principalmente los siguientes aportes: Debido a que los aerogeneradores varían según su capacidad y modelo; mediante la técnica Hardware In The Loop ; se logra la emulación del aerogenerador y evita el uso de un aerogenerador real, otorgando flexibilidad en el diseño del mismo y su control. Así también, las estrategias de control de corriente por medio de controladores resonantes y metodología Active Damping, permite inyección de corriente a la red con baja distorsión armónica. Finalmente, la plataforma experimental implementada logra presentar un escenario cercano a la realidad de un sistema de generación eólica con conexión a la red por medio de un interface de electrónica de potencia. Su importancia radica debido a la validación de los resultados experimentales, en la habilidad para testear cada uno de los componentes que conforman el sistema implementado y realizar futuras investigaciones a cada uno de ellos de manera rigurosa. Así como también, es objeto de integración a otros sistemas, como por ejemplo, al de una micro-red en operación modo isla y modo red por medio de Droop Control.
63

Modelling of Auxiliary Devices for a Hardware-in-the-Loop Application / Modellering av hjälpaggregat för en hardware-in-the-loop-applikation

Olsén, Johan January 2005 (has links)
<p>The engine torque is an important control signal. This signal is disturbed by the devices mounted on the belt. To better be able to estimate the torque signal, this work aims to model the auxiliary devices'influence on the crankshaft torque. Physical models have been developed for the air conditioning compressor, the alternator and the power steering pump. If these models are to be used in control unit function development and testing, they have to be fast enough to run on a hardware-in-the-loop simulator in real time. The models have been simplified to meet these demands. </p><p>The compressor model has a good physical basis, but the validity of the control mechanism is uncertain. The alternator model has been tested against a real electronic control unit in a hardware-in-the-loop simulator, and tests show good results. Validation against measurements is however necessary to confirm the results. The power steering pump model also has a good physical basis, but it is argued that a simple model relating the macro input-output power could be more valuable for control unit function development.</p>
64

Model-Based Validation of Fuel Cell Hybrid Vehicle Control Systems

Wilhelm, Erik 31 July 2007 (has links)
Hydrogen fuel cell technology has emerged as an efficient and clean alternative to internal combustion engines for powering vehicles, and hydrogen powertrains will aid in addressing key environmental issues such as urban air quality and global warming. This work demonstrates the effectiveness of a „hardware-in-loop‟ (HIL) simulation system for validating the safety and effectiveness of control algorithms for a hydrogen fuel cell hybrid passenger vehicle. A significant amount of the work completed in conjunction with the thesis topic was the design and construction of the fuel cell vehicle for competition. Producing a „rolling test bench‟ that generates data to be used to create HIL simulation models required nearly two years of work before an acceptable level of reliability was reached to produce usable data. Some detail will be given in this thesis regarding the infrastructure modifications required to safely build a hydrogen fuel cell vehicle, as well as the design challenges faced in the integration of a fuel cell power module, two electric drive motors, a nickel metal hydride battery, and required power electronics into a small sport utility vehicle originally designed for an internal combustion powertrain. The virtual control validation performed involved designing dynamic models of the systems of interest and performing real-time simulation to ensure that the appropriate controller response is observed. For this thesis, emphasis was placed on several key vehicle control topics. Communication robustness was evaluated to ensure that the complicated vehicle communication network could effectively handle traffic from the six powertrain sub-controllers. Safety algorithms were tested for appropriate response to fault conditions. Control systems were developed and tuned offline reducing the amount of time required for in-vehicle development and testing. Software-in-the-loop simulation was used to check initial code integrity and to validate the hardware-in-the-loop vehicle models. The methodology presented in this work was found to be sufficient for a thorough safety and rationality evaluation of control strategies for hybrid fuel cell vehicles.
65

Modelling of Auxiliary Devices for a Hardware-in-the-Loop Application / Modellering av hjälpaggregat för en hardware-in-the-loop-applikation

Olsén, Johan January 2005 (has links)
The engine torque is an important control signal. This signal is disturbed by the devices mounted on the belt. To better be able to estimate the torque signal, this work aims to model the auxiliary devices'influence on the crankshaft torque. Physical models have been developed for the air conditioning compressor, the alternator and the power steering pump. If these models are to be used in control unit function development and testing, they have to be fast enough to run on a hardware-in-the-loop simulator in real time. The models have been simplified to meet these demands. The compressor model has a good physical basis, but the validity of the control mechanism is uncertain. The alternator model has been tested against a real electronic control unit in a hardware-in-the-loop simulator, and tests show good results. Validation against measurements is however necessary to confirm the results. The power steering pump model also has a good physical basis, but it is argued that a simple model relating the macro input-output power could be more valuable for control unit function development.
66

Model-Based Validation of Fuel Cell Hybrid Vehicle Control Systems

Wilhelm, Erik 31 July 2007 (has links)
Hydrogen fuel cell technology has emerged as an efficient and clean alternative to internal combustion engines for powering vehicles, and hydrogen powertrains will aid in addressing key environmental issues such as urban air quality and global warming. This work demonstrates the effectiveness of a „hardware-in-loop‟ (HIL) simulation system for validating the safety and effectiveness of control algorithms for a hydrogen fuel cell hybrid passenger vehicle. A significant amount of the work completed in conjunction with the thesis topic was the design and construction of the fuel cell vehicle for competition. Producing a „rolling test bench‟ that generates data to be used to create HIL simulation models required nearly two years of work before an acceptable level of reliability was reached to produce usable data. Some detail will be given in this thesis regarding the infrastructure modifications required to safely build a hydrogen fuel cell vehicle, as well as the design challenges faced in the integration of a fuel cell power module, two electric drive motors, a nickel metal hydride battery, and required power electronics into a small sport utility vehicle originally designed for an internal combustion powertrain. The virtual control validation performed involved designing dynamic models of the systems of interest and performing real-time simulation to ensure that the appropriate controller response is observed. For this thesis, emphasis was placed on several key vehicle control topics. Communication robustness was evaluated to ensure that the complicated vehicle communication network could effectively handle traffic from the six powertrain sub-controllers. Safety algorithms were tested for appropriate response to fault conditions. Control systems were developed and tuned offline reducing the amount of time required for in-vehicle development and testing. Software-in-the-loop simulation was used to check initial code integrity and to validate the hardware-in-the-loop vehicle models. The methodology presented in this work was found to be sufficient for a thorough safety and rationality evaluation of control strategies for hybrid fuel cell vehicles.
67

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.
68

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.
69

A Framework for the Development of Scalable Heterogeneous Robot Teams with Dynamically Distributed Processing

Martin, Adrian 08 August 2013 (has links)
As the applications of mobile robotics evolve it has become increasingly less practical for researchers to design custom hardware and control systems for each problem. This research presents a new approach to control system design that looks beyond end-of-lifecycle performance and considers control system structure, flexibility, and extensibility. Toward these ends the Control ad libitum philosophy is proposed, stating that to make significant progress in the real-world application of mobile robot teams the control system must be structured such that teams can be formed in real-time from diverse components. The Control ad libitum philosophy was applied to the design of the HAA (Host, Avatar, Agent) architecture: a modular hierarchical framework built with provably correct distributed algorithms. A control system for exploration and mapping, search and deploy, and foraging was developed to evaluate the architecture in three sets of hardware-in-the-loop experiments. First, the basic functionality of the HAA architecture was studied, specifically the ability to: a) dynamically form the control system, b) dynamically form the robot team, c) dynamically form the processing network, and d) handle heterogeneous teams. Secondly, the real-time performance of the distributed algorithms was tested, and proved effective for the moderate sized systems tested. Furthermore, the distributed Just-in-time Cooperative Simultaneous Localization and Mapping (JC-SLAM) algorithm demonstrated accuracy equal to or better than traditional approaches in resource starved scenarios, while reducing exploration time significantly. The JC-SLAM strategies are also suitable for integration into many existing particle filter SLAM approaches, complementing their unique optimizations. Thirdly, the control system was subjected to concurrent software and hardware failures in a series of increasingly complex experiments. Even with unrealistically high rates of failure the control system was able to successfully complete its tasks. The HAA implementation designed following the Control ad libitum philosophy proved to be capable of dynamic team formation and extremely robust against both hardware and software failure; and, due to the modularity of the system there is significant potential for reuse of assets and future extensibility. One future goal is to make the source code publically available and establish a forum for the development and exchange of new agents.
70

A Framework for the Development of Scalable Heterogeneous Robot Teams with Dynamically Distributed Processing

Martin, Adrian 08 August 2013 (has links)
As the applications of mobile robotics evolve it has become increasingly less practical for researchers to design custom hardware and control systems for each problem. This research presents a new approach to control system design that looks beyond end-of-lifecycle performance and considers control system structure, flexibility, and extensibility. Toward these ends the Control ad libitum philosophy is proposed, stating that to make significant progress in the real-world application of mobile robot teams the control system must be structured such that teams can be formed in real-time from diverse components. The Control ad libitum philosophy was applied to the design of the HAA (Host, Avatar, Agent) architecture: a modular hierarchical framework built with provably correct distributed algorithms. A control system for exploration and mapping, search and deploy, and foraging was developed to evaluate the architecture in three sets of hardware-in-the-loop experiments. First, the basic functionality of the HAA architecture was studied, specifically the ability to: a) dynamically form the control system, b) dynamically form the robot team, c) dynamically form the processing network, and d) handle heterogeneous teams. Secondly, the real-time performance of the distributed algorithms was tested, and proved effective for the moderate sized systems tested. Furthermore, the distributed Just-in-time Cooperative Simultaneous Localization and Mapping (JC-SLAM) algorithm demonstrated accuracy equal to or better than traditional approaches in resource starved scenarios, while reducing exploration time significantly. The JC-SLAM strategies are also suitable for integration into many existing particle filter SLAM approaches, complementing their unique optimizations. Thirdly, the control system was subjected to concurrent software and hardware failures in a series of increasingly complex experiments. Even with unrealistically high rates of failure the control system was able to successfully complete its tasks. The HAA implementation designed following the Control ad libitum philosophy proved to be capable of dynamic team formation and extremely robust against both hardware and software failure; and, due to the modularity of the system there is significant potential for reuse of assets and future extensibility. One future goal is to make the source code publically available and establish a forum for the development and exchange of new agents.

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