Dissertations / Theses on the topic 'Automotive Front End Structure'

Nowadays, occupant safety becomes one of the most important research area and the automotive industry increased their efforts for enhancing the safety of the vehicles. The aim of this research is to investigate the effect of vehicle dynamics control systems (VDCS) on both the collision of the vehicle body and the kinematics behaviour of the vehicle's occupant. In this work, a novel vehicle dynamics/crash mathematical model is proposed and developed to co-simulate the crash event with the VDCS. This model is achieved using the novel approach of integrating front-end structure and vehicle dynamics mathematical models. The proposed mathematical model integrates both anti-lock braking systems (ASS) and active suspension control (ASC) systems alongside with crash structure modelling. This model is developed by generating its equations of motion and solving them numerically, this approach is used due to its quick and accurate analysis. In addition, a new multi-body occupant mathematical model is developed to capture the occupant kinematics before and during the collision. Validations of the proposed mathematical models are achieved to ensure their accuracy by comparing the simulated results with other real crash test data and former models results. The validation analysis of the vehicle and occupant models shows that the comparison results are well matched and the models are valid and can be used for different crash scenarios. The numerical simulation results are divided into two parts for vehicle and occupant models, respectively. Related to the vehicle model, it is shown that the mathematical model is flexible and useful for optimization studies. The results show that the deformation of the front-end structure is reduced, the vehicle body pitching and yawing angles are notably reduced, and the vehicle pitching acceleration is greatly reduced. Related to the occupant model, it is shown that the VDCS does have a significant effect on the rotations of the occupant's chest and head owing to its effect on the vehicle pitching. In addition, the occupant's deceleration is also slightly decreased and the occupant safety is improved.

Thesis (S.M.)--Massachusetts Institute of Technology, System Design and Management Program, 2008.
Includes bibliographical references (leaves 116-118).
The partitioning of a system can and will dictate the creative space for a designer or engineer. This thesis will analyze how using a new automotive architecture known as a Front End Module (FEM) can affect a limited specific subset of stakeholders. Through the use of interviews of subject matter experts, literature research and the use of System Design Management tools, an in depth analysis will be done on the FEM and how it affects the craftsmanship, damageability and assembly attributes. It will be shown how the craftsmanship attribute can be improved through the strategic use of FEM's to allow for a feed-forward system where build data are incorporated into upcoming FEM builds. Even with this advantage, the FEM architecture will not negatively impact the damageability attribute or assembly attribute if the proper design cues and strategies are followed. The FEM will also be intensely analyzed using the tools from the MIT SDM program where it will be evaluated as an architecture itself through the specific and targeted intent and beneficiary breakdown. The analysis will also include an Object/Process Mapping analysis where it will be proposed that the true customer of the automotive front end is not the individual that purchased the vehicle but rather the visual society as a whole. Finally, a managerial approach will be taken for the analysis of the inherent and inevitable supplier relationship that is required with using this FEM architecture. Interviews were conducted with two suppliers of OEM's and their common road blocks will be analyzed such as lack of holistic thinking or failure to understand the role of the system integrator. Proposed next steps will be laid out to address these barriers in order to open the communication channels between the supply base and the Original Equipment Manufacturers.
by Vincent R. Mahé.
S.M.

System dynamics modelling has been used for around 40 years to address complex, systemic, dynamic problems, those often described as wicked. But, system dynamics modelling is not an exact science and arguments about the most suitable techniques to use in which circumstances, continues. The nature of these wicked problems is investigated through a series of case studies where poor situational awareness among stakeholders was identified. This was found to be an underlying cause for management failure, suggesting need for better ways of recognising and managing wicked problem situations. Human cognition is considered both as a limitation and enabler to decision-making in wicked problem environments. Naturalistic and deliberate decision-making are reviewed. The thesis identifies the need for integration of qualitative and quantitative techniques. Case study results and a review of the literature led to identification of a set of principles of method to be applied in an integrated framework, the aim being to develop an improved way of addressing wicked problems. These principles were applied to a series of cases in an action research setting. However, organisational and political barriers were encountered. This limited the exploitation and investigation of cases to varying degrees. In response to a need identified in the literature review and the case studies, a tool is designed to facilitate analysis of multi-factorial, non-linear causality. This unique tool and its use to assist in problem conceptualisation, and as an aid to testing alternate strategies, are demonstrated. Further investigation is needed in relation to the veracity of combining causal influences using this tool and system dynamics, broadly. System dynamics modelling was found to have utility needed to support analysis of wicked problems. However, failure in a particular modelling project occurred when it was found necessary to rely on human judgement in estimating values to be input into the models. This was found to be problematic and unacceptably risky for sponsors of the modelling effort. Finally, this work has also identified that further study is required into: the use of human judgement in decision-making and the validity of system dynamics models that rely on the quantification of human judgement.

碩士
國立臺北科技大學
車輛工程系所
105
High boost DC/DC voltage conversion is always required in a power electronic interface for certain battery-powered electrical devices. However, a conventional boost converter operates with a large duty cycle for such high voltage gain, which results in increased power consumptions and low reliability problems. To solve this issue, a new battery-powered integrated boost converter for automotive audio amplifier is presented. The proposed converter uses an interleaved structure consisting of two phases. In the first phase, a conventional boost converter is employed, and in the second phase, the inverted version of this circuit is used. With this technique, a higher boost voltage gain can be achieved compared with conventional two-phase interleaved boost converters. A derivation of the operating principles of the proposed converter, analyzes of its topology, and the closed-loop control design are performed in this study. Furthermore, simulations and experiments are also performed using a battery input voltage of 12V for a 120W circuit. A reasonable duty cycle is selected to achieve an output voltage of 60V. Finally, the proposed converter is applied with the automotive audio amplifier to verify its feasibility. The measured maximum conversion efficiency of the converter is 98.7%, and the efficiency at full load is 89.1%.

碩士
國立清華大學
資訊工程學系
104
The Rectangle Tree Grammar (RTG) algorithm is a method for generic RNA secondary structure prediction. Though the flexibility brought by this algorithm is tremendous, a visualized, user-friendly, and easy-to-use interface is still in need. For this purpose, we have built a web-based interface, WebRTG, which simplies the input and visualizes the output of the RTG algorithm. In this thesis, we shall describe the functionality of the RTG algorithm, as well as the implementation details of the WebRTG interface.

碩士
國立交通大學
電信工程研究所
103
This thesis consists of three parts. All the proposed circuit were implemented in TSMC 0.18μm mixed-signal/RF CMOS 1P6M technology. Part I present a three-stage wideband LNA design in k-band. This LNA design use two-stage common-source and one-stage cascode structure. The simulation result shows the noise and power of the proposed circuit is low while the gain is high. The measurement result, however, is not as good as the simulation result owing to the oscillation occurring on certain frequency. According to the 3-dB bandwidth is 23 – 26 GHz and the peak gain is 8 dB at 21 GHz. The input return loss and output return loss are below -10 dB. The noise figure is 5.5 – 6.8 over the frequency band. The P1dB is -7dBm and IIP3 is -1.15 dBm at 24GHz. Total power dissipation is 23.4mW. The measured FOM of the proposed LNA is 0.227. Part II proposed a high gain down-conversion mixer with capacitance cross-coupled technique. The first stage of the proposed design is a differential LNA with cross-coupled design; the switching stage uses the current bleeding technique; these ensure high gain and low power dissipation. Due to the imperfect post-simulation, the measurement oscillates at the IF frequency. The simulated gain of the mixer reaches 19.53 dB and the 3-dB BW is 9GHz; the double-side band minimum noise figure is 7.5 dB; the P1dB is -13.7 dBm and the IIP3 is -9dBm at 24GHz. The power dissipation excludes the output buffer is 4.79mW. Part III presents a 24GHz high gain low power receiver front-end. In this chapter a new LNA and balun is implemented and the mixer is reused in last chapter. The conversion gain is 31dB and the noise figure is 5.45 dB; IIP3 is -11 dBm and the P1dB is -25 dBm at 24GHz. The LO-IF leakage is less than -50 dB; the LO-RF leakage is less than -50dB; the RF-IF leakage is less than -35dB. Total power consumption excluded output buffer is 24.59 mW.

碩士
國立中山大學
通訊工程研究所
99
This thesis is composed of two parts: a high-speed transceiver front-end design with fault detection for FlexRay-based automative communication systems, and a temperature detector. In the first topic, a high-speed transceiver design with a fault detection circuit compliant with FlexRay standards V2.1 is proposed and realized on silicon. According to FlexRay physical layer standards, a LVDS-like transmitter is utilized to drive the twisted pair to generate a pair of differential signals. By contrast, a three-comparator-based receiver will recover the signals and then detect the mode of the bus. A failure detector is added at the transmitter to detect the operating current magnitude to avoid any over-current hazard. Meanwhile, a short-circuit detector is added at the receiver to detect short-circuit faults to vdd or gnd. The second topic discloses a temperature detector circuit, particularly dedicated for the reliability of any in-car system by sensing the temperature and the process at the same time. A discharging circuit composed of four PMOS transistors discharges until the output voltage is stable. It is composed of several reference voltages and comparators to determine the range of temperature and process. Eventually, by identifying the process corner and the temperature range, the reliability and safty of the car electrics will be ensured.

碩士
長庚大學
電子工程學研究所
97
This thesis proposes a new structure of microwave coupler by placing a floating plate over the parallel-coupled lines to enhance the coupling between lines, and then we realize a coupler with a stepped impedance configuration to shorten its physical length. By using the stepped impedance coupler muliti-sectional broadband coupler is implemented. And the realization of a stepped impedance balun in coplanar waveguide. A three sectional broadband coupler is constructed by stepped impedance to shorten the physical length o the coupler. Because the main difficulty of realizing the broadband coupler is that it needs at least one section of the coupler to have quite high coupling factor, therefore, we use the coupler consisting of floating plates to overcome such a problem. A prototype operating over 1~5GHz is designed and fabricated. The measured amplitude balance is less then ±1dB; the phase difference is less than 90°±10°, the fractional bandwidth is about 113%. Then a new type of balun is implemented by connecting the two stepped impedance coplanar wave guide coupler. The new type of balun consists of two coupler and one transmission line. The required electrical length and coupling coefficient of the coupled line and the electrical length and impedance of transmission line to construct a balun with short physical length is studied. The higher impedance of the transmission line in the designed passband and the stronger coupling coefficient of the coupled lines can furthermore miniaturize the size of tightly coupled lines. The measurement results of output ports amplitude balance is less then ±1dB; phase difference is 180°±5°, the fractional bandwidth is 26.5%.

碩士
華梵工學院
電子研究所
85
Abstract Step impedance coupled line band-pass filter is analyzed both theoretically and experimentally in this thesis. We use Odd/Even mode excitation method in the t- wo port network theory to find out the transfer function of our filter. Then, we use the method of amplitude approximation to derive the transfer function from our specification. After we get the two transfer functions from our filter stru- cture and specification, we can use the pole and zero synthesis method to obtain the ideal structure of our filter. Then, we put these structure into an EM soft ware to fine-tune the filter's size. The experiment is discussed in detail and is carefully calibrated by the TRL (Through-Reflection-Line) calibration method. We first employ microstrip line to implement our filter. We then use the LTCC (Low temperature co-fired ceramic) process to realize a multilayer ceramic filter. Good agreement between theory and experiment is obtained. Besides, we have successfully derived the equivalent circuit of our filter. We also have proved the validity of this equivalent circuit by the design example . Keyword：Step impedance coupled line band-pass filter, Odd/Even mode excitation method, amplitude approximation, Low temperature co-fired ceramic, multilayer ceramic filter.

Esta tese estuda o projecto e o comportamento de filtros em tempo contínuo de muito-alta-frequência. A motivação deste trabalho foi a investigação de soluções de filtragem para canais de leitura em sistemas de gravação e reprodução de dados em suporte magnético, com custos e consumo (tamanho total inferior a 1 mm2 e consumo inferior a 1mW/polo), inferiores aos circuitos existentes. Nesse sentido, tal como foi feito neste trabalho, o rápido desenvolvimento das tecnologias de microelectrónica suscitou esforços muito significativos a nível mundial com o objectivo de se investigarem novas técnicas de realização de filtros em circuito integrado monolítico, especialmente em tecnologia CMOS (Complementary Metal Oxide Semiconductor). Apresenta-se um estudo comparativo a diversos níveis hierárquicos do projecto, que conduziu à realização e caracterização de soluções com as características desejadas. Num primeiro nível, este estudo aborda a questão conceptual da gravação e transmissão de sinal bem como a escolha de bons modelos matemáticos para o tratamento da informação e a minimização de erro inerente às aproximações na conformidade aos princípios físicos dos dispositivos caracterizados. O trabalho principal da tese é focado nos níveis hierárquicos da arquitectura do canal de leitura e da realização em circuito integrado do seu bloco principal – o bloco de filtragem. Ao nível da arquitectura do canal de leitura, apresenta-se um estudo alargado sobre as metodologias existentes de adaptação de sinal e recuperação de dados em suporte magnético. Este desígnio aparece no âmbito da proposta de uma solução de baixo custo, baixo consumo, baixa tensão de alimentação e baixa complexidade, alicerçada em tecnologia digital CMOS, para a realização de um sistema DFE (Decision Feedback Equalization) com base na igualização de sinal utilizando filtros integrados analógicos em tempo contínuo. Ao nível do projecto de realização do bloco de filtragem e das técnicas de implementação de filtros e dos seus blocos constituintes em circuito integrado, concluiu-se que a técnica baseada em circuitos de transcondutância e condensadores, também conhecida como filtros gm-C (ou transcondutância-C), é a mais adequada para a realização de filtros adaptativos em muito-alta-frequência. Definiram-se neste nível hierárquico mais baixo, dois subníveis de aprofundamento do estudo no âmbito desta tese, nomeadamente: a pesquisa e análise de estruturas ideais no projecto de filtros recorrendo a representações no espaço de estados; e, o estudo de técnicas de realização em tecnologia digital CMOS de circuitos de transcondutância para a implementação de filtros integrados analógicos em tempo contínuo. Na sequência deste estudo, apresentam-se e comparam-se duas estruturas de filtros no espaço de estados, correspondentes a duas soluções alternativas para a realização de um igualador adaptativo realizado por um filtro contínuo passa-tudo de terceira ordem, para utilização num canal de leitura de dados em suporte magnético. Como parte constituinte destes filtros, apresenta-se uma técnica de realização de circuitos de transcondutância, e de realização de condensadores lineares usando matrizes de transístores MOSFET para processamento de sinal em muito-alta-frequência realizada em circuito integrado usando tecnologia digital CMOS submicrométrica. Apresentam-se métodos de adaptação automática capazes de compensar os erros face aos valores nominais dos componentes, devidos às tolerâncias inerentes ao processo de fabrico, para os quais apresentamos os resultados de simulação e de medição experimental obtidos. Na sequência deste estudo, resultou igualmente a apresentação de um circuito passível de constituir uma solução para o controlo de posicionamento da cabeça de leitura em sistemas de gravação/reprodução de dados em suporte magnético. O bloco proposto é um filtro adaptativo de primeira ordem, com base nos mesmos circuitos de transcondutância e técnicas de igualação propostos e utilizados na implementação do filtro adaptativo de igualação do canal de leitura. Este bloco de filtragem foi projectado e incluído num circuito integrado (Jaguar) de controlo de posicionamento da cabeça de leitura realizado para a empresa ATMEL em Colorado Springs, e incluído num produto comercial em parceria com uma empresa escocesa utilizado em discos rígidos amovíveis.
This thesis studies the design and behavior of continuous-time very-high-frequency filters. The motivation of this work was the search for filtering solutions for the readchannel in recording and reproduction of data on magnetic media systems, with costs and consumption (total size less than 1 mm2 and consumption under 1mW/pole), lower than the available circuits. Accordingly, as was done in this work, the rapid development of microelectronics technology raised very significant efforts worldwide in order to investigate new techniques for implementing such filters in monolithic integrated circuit, especially in CMOS technology (Complementary Metal Oxide Semiconductor). We present a comparative study on different hierarchical levels of the project, which led to the realization and characterization of solutions with the desired characteristics. In the first level, this study addresses the conceptual question of recording and transmission of signal and the choice of good mathematical models for the processing of information and minimization of error inherent in the approaches and in accordance with the principles of the characterized physical devices. The main work of this thesis is focused on the hierarchical levels of the architecture of the read channel and the integrated circuit implementation of its main block - the filtering block. At the architecture level of the read channel this work presents a comprehensive study on existing methodologies of adaptation and signal recovery of data on magnetic media. This project appears in the sequence of the proposed solution for a lowcost, low consumption, low voltage, low complexity, using CMOS digital technology for the performance of a DFE (Decision Feedback Equalization) based on the equalization of the signal using integrated analog filters in continuous time. At the project level of implementation of the filtering block and techniques for implementing filters and its building components, it was concluded that the technique based on transconductance circuits and capacitors, also known as gm-C filters is the most appropriate for the implementation of very-high-frequency adaptive filters. We defined in this lower level, two sub-levels of depth study for this thesis, namely: research and analysis of optimal structures for the design of state-space filters, and the study of techniques for the design of transconductance cells in digital CMOS circuits for the implementation of continuous time integrated analog filters. Following this study, we present and compare two filtering structures operating in the space of states, corresponding to two alternatives for achieving a realization of an adaptive equalizer by the use of a continuous-time third order allpass filter, as part of a read-channel for magnetic media devices. As a constituent part of these filters, we present a technique for the realization of transconductance circuits and for the implementation of linear capacitors using arrays of MOSFET transistors for signal processing in very-high-frequency integrated circuits using sub-micrometric CMOS technology. We present methods capable of automatic adjustment and compensation for deviation errors in respect to the nominal values of the components inherent to the tolerances of the fabrication process, for which we present the simulation and experimental measurement results obtained. Also as a result of this study, is the presentation of a circuit that provides a solution for the control of the head positioning on recording/playback systems of data on magnetic media. The proposed block is an adaptive first-order filter, based on the same transconductance circuits and equalization techniques proposed and used in the implementation of the adaptive filter for the equalization of the read channel. This filter was designed and included in an integrated circuit (Jaguar) used to control the positioning of the read-head done for ATMEL company in Colorado Springs, and part of a commercial product used in removable hard drives fabricated in partnership with a Scottish company.

碩士
國立交通大學
電信工程系所
97
This paper proposes two designs of antennas. One is the research of the on-chip antenna, the other one is the topic of the high front-to-back ratio quasi-Yagi antenna. For the first topic, a 24 / 60GHz dual-band millimeter-wave on-chip antenna is presented here. We design the feeding network by using the coplanar waveguide (CPW) structure. For the dual-band design, there are two major current paths to radiate. To avoid the harmonic frequency band of the low frequency-band, we add two strips to couple the harmonic frequency of the low frequency-band. Besides, the two strips let the higher frequency-band performance better. Then, the second topic, a novel structure for end-fire antenna, is introduced here. By the reduce the ground plane, adding short-circuited with ground stubs and choosing the appropriate position and the size of the connecting metal squares where the antenna body and the short-circuited stubs are connected, we can obtain the end-fire radiation pattern. And the front-to-back ratio of this design will increase as well as the operating frequency is increasing. And the third topic, a high front-to-back ratio quasi-Yagi antenna is demonstrated here. The antenna consists of three parts which are the reflector, or ground of the antenna, the driver, and the directors. It has three directors of this quasi Yagi antenna to improve the antenna gain and the front-to-back ratio. Here, it is worth to be noticeable that the positions of the dipole arms are not at the symmetric location. The one extended from the ground plane is a few farther to the ground plane than the one extended from the signal path for improving the performance. At last, we will show the enhance type of the high gain and high front-to-back ratio quasi-Yagi antenna.