In-car communication systems (ICCS) are becoming more frequently used by drivers. ICCS are used in order to minimise the driving distraction due to using a mobile phone while driving. Several usability studies of ICCS utilising speech user interfaces (SUIs) have identified usability issues that can affect the workload, performance, satisfaction and user experience of the driver. This is due to current speech technologies which can be a source of errors that may frustrate the driver and negatively affect the user experience. The aim of this research was to design a new multimodal interface that will manage the interaction between an ICCS and the driver. Unlike the current ICCS, it should make more voice input available, so as to support tasks (e.g. sending text messages; browsing the phone book, etc), which still require a cognitive workload from the driver. An adaptive multimodal interface was proposed in order to address current ICCS issues. The multimodal interface used both speech and manual input; however only the speech channel is used as output. This was done in order to minimise the visual distraction that graphical user interfaces or haptics devices can cause with current ICCS. The adaptive interface was designed to minimise the cognitive distraction of the driver. The adaptive interface ensures that whenever the distraction level of the driver is high, any information communication is postponed. After the design and the implementation of the first version of the prototype interface, called MIMI, a usability evaluation was conducted in order to identify any possible usability issues. Although voice dialling was found to be problematic, the results were encouraging in terms of performance, workload and user satisfaction. The suggestions received from the participants to improve the system usability were incorporated in the next implementation of MIMI. The adaptive module was then implemented to reduce driver distraction based on the driver‟s current context. The proposed architecture showed encouraging results in terms of usability and safety. The adaptive behaviour of MIMI significantly contributed to the reduction of cognitive distraction, because drivers received less information during difficult driving situations.

prepared by Ling Hok Sun, Lawrence. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1998. / Abstract also in Chinese. / Chapter 1. --- Abstract --- p.2 / Chapter 2. --- Introduction --- p.3 / Chapter 3. --- Circuit Description --- p.8 / Chapter 4. --- Technology' --- p.10 / Chapter 5. --- Design --- p.13 / Chapter 5.1 --- TOP LEVEL --- p.13 / Chapter 5.2 --- Logic --- p.14 / Chapter 5.3 --- Tuner --- p.19 / Chapter 5.4 --- Gate Drive and Power Switch --- p.26 / Chapter 5.5 --- Full-Circuit Simulation --- p.43 / Chapter 6. --- Layout --- p.53 / Chapter 7. --- Characterization --- p.55 / Chapter 8. --- Conclusion --- p.65 / Chapter 9. --- Reference --- p.66 / Chapter 10. --- Appendix --- p.67

M.Tech. (Mechanical Engineering) / This dissertation focuses on understanding the relation between aerodynamic drag and aerodynamic lift in modern passenger cars and explores what effect these forces have on a vehicle. Modern cars are capable of exceptionally high speed and are subjected to large destabilizing lift forces at these speeds. To counteract the effects of positive lift, various aerodynamic devices and body design details are included in the typical car design. These devices often increase the vehicles aerodynamic drag, reducing energy efficiency as speed increases. The problem that this project aims to address is that at typical commuting speeds where lift forces are low these counter lift devices are not required, however because these devices are fixed the losses associated with their increased drag is still incurred. The devices can however not be excluded from the design as they are required on occasions that the vehicle is driven at abnormally high speed and lift forces become large. The losses associated with the increased drag of such devices are incurred over the vehicles full range of speeds even though the devices are only required at higher speed. The objective of this project is to develop an aerodynamic system that allows the vehicle to continuously and autonomously adjust its drag vs. lift properties to an optimal compromise that suits the vehicles instantaneous aerodynamic requirements. The system offers improvements in both handling and breaking performance as well as increased energy efficiency. The feasibility and effectiveness of the developed system is compared against the performance of a standard test vehicle and against the same test vehicle equipped with various traditional fixed aerodynamic devices. The methods used to develop, analyse and compare the various test models include both practical testing of a physical vehicle and computer based simulation using a digitized model of the same vehicle. Practical testing was conducted at Gerotek test facilities in Pretoria, South Africa and includes measuring the flow rate through the engine cooling system to determine the drag contribution of the cooling system to total vehicle drag. Coast-down testing is used to characterise the test vehicles rolling resistance and skid-pan or circuit tests are used to characterise the vehicles handling properties. Acceleration and breaking tests are also performed. Data from these tests are recorded through various on-board data logging units with pitot tube, GPS and accelerometer devices as inputs. A 3D model of the test vehicle is compiled using photogrammetry software to capture the profile and dimensions of the test vehicle into digital form. A 3D CAD model is developed from the vehicle scan and is used for CFD simulations to solve for the vehicles aerodynamic properties and to assist in the design and incorporation of the various adjustable aerodynamic devices required for the project. The data accumulated through computer simulation and practical testing is combined to form a statistical computer model of the standard vehicle. Research is conducted on existing aerodynamic devices common to passenger cars and suitable devices are adapted to three additional computer models: One with an adaptive aerodynamic system and two with fixed aerodynamic configurations of different intensities. The performance and energy efficiency of the four models are analytically simulated and the results are compared directly. The study shows that in terms of sporting performance around a theoretical road circuit, the adaptive model outperforms both the standard vehicle and fixed configuration models by a small degree, +-2.3%. The standard vehicle is found to have a lift coefficient CL=0.43 with a drag coefficient of Cd=0.31. The dynamic model is able to realize combinations of low drag or low lift between the limits of Cd=0.3, CL=0.34 and Cd=0.32, CL=0.03. The variable aerodynamic properties allow for a 5.5% increase in maximum cornering speed and a 20% improvement in acceleration time from standstill to terminal speed. The percentage improved lap time would be greater if the effects of breaking from the higher terminal speed achieved by the dynamic model were ignored for the simulation...

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The purpose of this project was to develop two-semester unit plans for the auto electronics course in the automotive technology program at Fontana High School.

This study aims to experimentally investigate the spray cooling characteristics for active two-phase cooling of automotive power electronics. Tests are conducted on a small-scale, closed loop spray cooling system featuring a pressure atomized spray nozzle. Two types of refrigerants, HFC-134a (R-134a) and HFO-1234yf, are selected as the working fluids. The test section (heater), made out of oxygen-free copper, has a 1-cm2 plain, smooth surface prepared following a consistent procedure, and would serve as a baseline case. Matching size thick film resistors, attached onto the copper heaters, generate heat and simulate high heat flux power electronics devices. The tests are conducted by controlling the heat flux in increasing steps, and recording the corresponding steady-state temperatures to obtain cooling curves. The working fluid is kept at room temperature level (22oC). Performance comparisons are made based on heat transfer coefficient (HTC) and critical heat flux (CHF) values. Effects of spray characteristics and liquid flow rates on the cooling performance are investigated with the selected coolants. Three types of commercially available nozzles that generate full-cone sprays with fine droplets are utilized in the tests. Effect of liquid flow rate is evaluated varying flow rates at 2, 3, 4 ml/s. The experimental results obtained from this study provide a framework for spray cooling performance with the current and next-generation refrigerants aimed for advanced thermal management of automotive power electronics.

Over the past decade, the satellite industry has witnessed the birth and evolution of the CubeSat standard, not only as a technology demonstrator tool but also as a human capacity development platform in universities. The use of commercial off the shelf (COTS) hardware components makes the CubeSat a cost effective and ideal solution to gain access to space in terms of budget and integration time for experimental science payloads. Satellite operations are autonomous and are essentially based on the interaction of interconnected electronic subsystems exchanging data according to the mission requirements and objectives. The onboard computer (OBC) subsystem is developed around a microcontroller and plays an essential role in this exchange process as it performs all the computing tasks and organises the collection of onboard housekeeping and payload data before downlink during an overpass above the ground station. The thesis here presented describes the process involved in the development, design and implementation of a prototype OBC for a CubeSat. An investigation covering previously developed CubeSat OBCs is conducted with emphasis on the characteristics and features of the microcontroller to be used in the design and implementation phases. A set of hardware requirements are defined and according to the current evolution on the microcontroller market, preference is given to the 32-bit core architecture over both its 8-bit and 16-bit counterparts. Following a well defined selection process, Atmel’s AT91SAM3U4E microcontroller which implements a 32-bit Cortex-M3 core is chosen and an OBC architecture is developed around it. Further, the proposed architecture is implemented as a prototype on a printed circuit board (PCB), presenting a set of peripherals necessary for the operation of the OBC. Finally, a series of tests successfully conducted on some of the peripherals are used to evaluate the proposed architecture.

Os veículos automotivos pesados possuem funcionalidades particulares e aplicação em ambiente agressivo. Para garantir melhores desempenho, segurança e confiabilidade aos equipamentos eletrônicos embarcados, é necessário o aperfeiçoamento dos métodos e processos de desenvolvimento de software embarcado automotivo. Considerando a metodologia de desenvolvimento baseada em modelos (MBD) como um método em ascensão na indústria automotiva, este trabalho pesquisa contribuições nas atividades de engenharia de requisitos, otimização e validação do software, de forma a comprovar a eficácia do método e ferramentas utilizadas na busca pela qualidade final do produto (veículo comercial pesado). A base do trabalho refere-se à aplicação dos conceitos de integração de requisitos à simulação (MIL - Model in the Loop), comparação da otimização do software gerado automaticamente entre ferramentas comuns (IDE’s) e as baseadas em modelo, validação e cobertura do software gerado e uma forma alternativa de aumento da cobertura do código testado. / The automotive heavy-duty vehicles have particular functionalities and aggressive environment application. To ensure better performance, safety and reliability to electronic embedded equipment, it is necessary to invest in methods and process improvements in automotive software development. Considering Model Based Design (MBD) as an ascending development method in automotive industry, this work looks towards contributions in requirements engineering, software optimization and validation, in order to prove the method and tools efficiency in the final product quality (heavy-duty vehicle). This work refers to the appliance of requirement engineering integration to the simulation (MIL - Model in the Loop), comparison between optimization in usual programming tools (IDE’s) and Model Based Design tools, validation and software code coverage, and an alternative way of increasing code coverage of a tested code.

Os sistemas embarcados automotivos são caracterizados por sistemas computacionais que suportam funcionalidades na forma de softwares embarcados para proporcionar aos usuários maior conforto, segurança e desempenho. Entretanto, existe uma grande quantidade de funções integradas que elevam o nível de complexidade de forma que se deve utilizar métodos e ferramentas de projetos adequados para garantir os requisitos funcionais e não funcionais do sistema. Todo o projeto de software embarcado automotivo deve iniciar com a definição de requisitos funcionais e de acordo com a dinâmica do subsistema que uma ECU (Electronic Control Unit) irá controlar e/ou gerenciar, deve-se ainda definir os requisitos temporais. Uma função automotiva pode ter requisitos temporais do tipo, período de ativação, atraso fim-a-fim, deadline entre outras que por sua vez estão estritamente relacionadas com as características da arquitetura de hardware utilizada. Em um sistema automotivo, tem-se uma arquitetura de computação embarcada distribuída em que existem tarefas e mensagens que trocam sinais entre si e podem ter requisitos temporais que devam ser atendidos. A análise temporal para verificação e validação dos requisitos temporais pode ser realizada ao nível de arquitetura distribuída, tarefas e instruções sendo que a utilização adequada de métodos e ferramentas é uma condição necessária para sua verificação. Desta forma, apresenta-se uma descrição do estado da arte de análise temporal em sistemas embarcados automotivos, suas propriedades e a utilização das ferramentas da Gliwa para avaliar se os requisitos temporais são atendidos. Um exemplo ilustrativo foi implementado com o propósito de apresentar como os métodos, processos e ferramentas devem ser aplicados para verificar se os requisitos temporais definidos previamente no início do projeto foram atendidos e para que em um sistema já existente possam suportar funções adicionais com requisitos temporais a serem garantidos. É importante verificar que as ferramentas de análise temporal, tem o propósito ainda de verificar se os recursos computacionais estão sendo utilizados de acordo com o especificado no início do projeto. / Automotive embedded systems are characterized by computer systems that support embedded software functionalities to provide users with greater comfort, security and performance. However, there are a number of integrated functions that raise the level of complexity so that appropriate design methods and tools must be used to guarantee the functional and non-functional requirements of the system. All automotive embedded software design must begin with the definition of functional requirements and according to the dynamics of the subsystem that an ECU (Electronic Control Unit) will control and/or manage, it is necessary to define the time requirements. An automotive function may have time requirements of type, activation period, end-to-end delay and deadline among others which in turn are strictly related to the characteristics of the hardware architecture used. In an automotive system there is a distributed embedded computing architecture in which there are tasks and messages that exchange signals between them and may have timing requirements that must be met. The timing analysis for verification and validation of timing constrains can be carried out at the level of distributed architecture, tasks and instructions, and the proper use of methods and tools is a necessary condition for their verification. In this way, a description of the state of the art of timing analysis in automotive embedded systems, their properties and the use of the tools of Gliwa to evaluate if the timing constrains are met. An illustrative example has been implemented with the purpose of presenting how the methods, processes and tools should be applied to verify that the time requirements defined at the beginning of the project are met and that in an existing system can support additional functions with requirements to be guaranteed. It is important to note that timing analysis tools are still intended to verify that computational resources are being used as specified at the beginning of the project.

Os veículos automotivos possuem diversas funcionalidades em que, para ser melhoradas ou inovadas, é mandatório que se garanta melhor desempenho, segurança e confiabilidade. Para isto, é necessário criar, ou aperfeiçoar os já existentes, métodos e processos de desenvolvimento de software embarcado automotivo. As metodologias de desenvolvimento tradicionais não atendem aos requisitos e complexidade destes sistemas. Desta forma, a metodologia de desenvolvimento de software baseado em modelos (MBD – Model-Based Design) pode contribuir grandemente, por tornar possível a otimização com recursos de análise e testes. Por estes motivos, este trabalho busca demonstrar como se pode aplicar esta metodologia desenvolvimento baseado em modelos para as funções de software automotivo, considerando as etapas deste processo como MIL (Model-Inthe- Loop), SIL (Software-In-the Loop), PIL (Processor-In-the Loop) e RCP (Rapid Control Prototyping) e comprovar a sua eficácia. Considera-se ainda que foram utilizadas ferramentas compatíveis e essenciais para o processo de desenvolvimento, tais como para definição dos requisitos, elaboração da planta física, projeto controlador, verificação e testes. / The vehicles has many functions wherein, to be improve or innovated, is essential that the warranty of a better performance, safety and reliability. For this, is necessary to create, or improve the already existing, developing methods and processes of automotive embedded software. However, the traditional development methodologies do not meet the requirements and complexity of these systems. Therefore the methodology of model-based design (MBD) may contribute greatly, by making possible the optimization using analysis resources and tests. For these reasons, this work seeks to demonstrate how you can apply this development methodology based on models for automotive software functions, considering the steps in this process as MIL (Model-In-the-Loop), SIL (Software-In-the Loop), PIL (Processor-In-the Loop) and RCP (Rapid Control Prototyping) and prove its effectiveness. It is further considered that were used compatible and essential tools for the development process, such as for requirements definition, development of physical plant, controller design, verification and testing.