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The success of stratified combustion is strongly determined by the injection and ignition system used. A large temporal and spatial variation of the main parameters - mixture composition and charge motion - in the vicinity of the spark location are driving the demands for significantly improved ignition systems. Besides the requirements for conventional homogeneous combustion systems higher ignition energy and breakdown voltage capability is needed. The spark location or spark plug gap itself has to be open and well accessible for the mixture to allow a successful flame kernel formation and growth into the stratified mixture regime, while being insensitive to potential interaction with liquid fuel droplets or even fuel film. For this purpose several different ignition concepts are currently being developed. The present article will give an ignition system overview for stratified combustion within Delphi Powertrain Systems.

The complexity of automotive software and the needs for shorter development time and software portability require the development of new approaches and standards for software architectures. The AUTOSAR project is one of the most comprehensive and promising solutions for defining a methodology supporting a function-driven development process. Furthermore, it manifests itself as a standard for expressing compatible software interfaces at the Application Layer. This paper discusses the implementation of AUTOSAR requirements for the component structure, as well as interfaces to the Application Layer in a model-based development environment. The paper outlines the major AUTOSAR requirements for software components, provides examples of their implementation in a Simulink/Stateflow model, and describes the modelbased implementation of an operating system for running AUTOSAR software executables (“runnables”).

The Gasoline Engine Management Systems for passenger cars have the OBD-II (On Board Diagnostic) for United States of America market, the EOBD (European On Board Diagnostic) for Europe and OBD-BR1 and OBD-BR2 for Brazil. This paper presents the differences between these four On Board Diagnostic Systems.

The use of advanced electron microscopy techniques to characterize both the bulk and near-atomic level microstructural evolution of catalyst materials during different dynamometer/vehicle aging cycles is an integral part of understanding catalyst deactivation. The study described here was undertaken to evaluate thermally-induced microstructural changes which caused the progressive loss of catalyst performance in a three-way automotive catalyst. Several different catalyst processing variables, for example changing the washcoat ceria content, were also evaluated as a function of aging cycle and thermal history. A number of thermally-induced microstructural changes were identified using high resolution electron microscopy techniques that contributed to the deactivation of the catalyst, including sintering of all washcoat constituents, γ-alumina transforming to α-, β-, and δ-alumina, precious metal redistribution, and constituent encapsulation.

Intense competition in the automotive industry requires continuous reduction in innovation cycle time, even as corporations are downsizing and system complexity is increasing. Subsequently, the application of recently introduced Rapid Algorithm Development (RAD) tools has facilitated significant advances in the development of embedded control systems. The RAD steps include system modeling, control algorithm design, simulation analysis, automated calibration design, and vehicle implementation through automatic code generation. The application of RAD tools and the associated benefits are described, specifically in the context of Engine Management Systems (EMS). Such benefits include significant reductions in development cycle time, open architecture, automated calibration, and information reuse.

Short timing and complexes strategies are mandatory in a competitive market as automotive industry. Therefore quality problems identification during and after the coding phase, may be the difference between the business success and undesired conflicts with customer, solving problems that were not previously identified. Consequently the usage of technique Mahalanobis Taguchi System (MTS) to analyze coding metrics, create an environment to improve the final product quality and mitigate potential problems later identified.

The utilization of Laser welding process has increased during last years in several areas of industry, due to many benefits that can be achieved with this technology, such as: flexibility, productivity and quality. Thus, the optimization of Laser welding processes has been considered as a “green field” to be explored by Laser manufacturers, automation companies and process/project engineers. Nowadays there are few researches that provide a roadmap for Laser welding processes improvement that approaches both the aspects and characteristics applied to evaluate the Laser weld application performance. Therefore, this paper has per its main purpose through an exploratory study to provide parameters toward continuous improvement of Laser welding process considering both types of Lasers: Laser spot weld and Laser seam weld of stainless steel joints, thus this work may be considered as theoretical and practical reference to be applied by people involved with Laser welding applications.

One of the most evident trends in automotive sector is miniaturization. It is related to considerable benefits due to the potential of mass reduction, cost reduction and efficiency improvement. It involves many different automobile components and most of them are facing challenges to achieve the targets defined by car makers and final consumers. Specifically for wiring harness, it seems to be many manufacturing and process challenges to be surpassed in order to fully perceive the benefits expected with miniaturization, internally and externally. So this article aims to present an overview of literature as well as reporting of experts on this issue mentioning some of the challenges that global automotive wiring harness manufacturers are facing. Subjects as assembly automation, terminal connection and small gauge cables are discussed in the article and also a general overview of how those problems are being addressed in order to meet customer requirements.

This paper presents a brake pressure estimation algorithm for Delphi Traction Control Systems (TCS). A control oriented lumped parameter model of a brake control system is developed using Matlab/Simulink. The model is derived based on a typical brake system and is generic to other types of brake control hardware systems. For application purposes, the model is simplified to capture the dominant dynamic brake pressure response. Vehicle experimental data collected under various scenarios are used to validate the algorithm. Simulation results show that the algorithm gives accurate pressure estimation. In addition, the calibration procedure is greatly simplified

There are an increasing number of applications for resonant micromachines. Accelerometers, angular rate sensors, voltage controlled oscillators, pressure and chemical sensors have been demonstrated using this technology. Several of these devices are employed in vehicles. Vibrating devices have been made from silicon, quartz, GaAs, nickel and aluminum. Resonant microsystems are in constant motion and so present new challenges in the area of reliability for vehicular applications. The impact of temperature extremes, cyclic fatigue, stiction, thermal and mechanical shock on resonant device performance is covered.

This paper presents a theoretical and experimental study of a cylinder deactivation valvetrain system for the integration into an Engine Management System (EMS). A control-oriented lumped parameter model of the deactivation valvetrain system is developed and implemented using Matlab/Simulink, and validated by experimental data. Through simulation and experimental data analysis, the effect of operating conditions on the dynamic response is captured and characterized, over a wide range of operating conditions. The algorithm provides a basis for the calibration of the deactivation hardware. The generic characterization of the dynamic response can simplify the calibration parameters for the implementation in engine management systems.

Hazard analysis plays an important role in the development of safety-critical systems. Hazard analysis techniques have been used in the development of conventional automotive systems. However, as future automotive systems become more sophisticated in functionality, design, and applied technology, the need for a more comprehensive hazard analysis approach has arisen. In this paper, we describe a comprehensive hazard analysis approach for system safety programs. This comprehensive approach involves applying a number of hazard analysis techniques and then integrating their results. This comprehensive approach attempts to overcome the narrower scope of individual techniques while obtaining the benefits of all of them.

This paper describes an environment for the development of production Engine Management Systems (EMS). This includes a formal framework and modeling methodology. The environment is based on using Simulink/Stateflow for developing a control system executable specification and a plant model. This allows for simulations of the system to be performed at the engineer's desk, which is identical performance with production software. We provide the details for incorporating production legacy code into the Simulink/Stateflow control system. The system includes a multi-rate, and event driven operating system. This system is developed to facilitate new algorithm development and automated software testing. Based on Simulink/Stateflow this specification will be suitable for use with commercial automatic code generation tools.

In recent years, the increasing interest and requirements for improved engine diagnostics and control has led to the implementation of several different sensing and signal processing technologies. In order to optimize the performance and emission of an engine, detailed and specified knowledge of the combustion process inside the engine cylinder is required. In that sense, the torque generated by each combustion event in an IC engine is one of the most important variables related to the combustion process and engine performance. This paper introduces torque estimation techniques in the real-time basis for engine control applications using the measurement of crankshaft speed variation. The torque estimation scheme presented in this paper consists of two entirely different approaches, “Stochastic Analysis” and “Frequency Analysis”.

Lithium-based battery technology offers performance advantages over traditional battery technologies at the cost of increased monitoring and controls overhead. Multiple-cell Lead-Acid battery packs can be equalized by a controlled overcharge, eliminating the need to periodically adjust individual cells to match the rest of the pack. Lithium-based based batteries cannot be equalized by an overcharge, so alternative methods are required. This paper discusses several cell-balancing methodologies. Active cell balancing methods remove charge from one or more high cells and deliver the charge to one or more low cells. Dissipative techniques find the high cells in the pack, and remove excess energy through a resistive element until their charges match the low cells. This paper presents the theory of charge balancing techniques and the advantages and disadvantages of the presented methods.

The increasing features and complexity of today's automotive architectures are becoming increasingly difficult to manage. Each new innovation typically requires additional mechanical actuators and associated electrical controllers. The sheer number of black boxes and wiring are being limited not by features or cost but by the inability to physically assemble them into a vehicle. A new architecture is required which will support the ability to add new features but also enable the Vehicle Assembly Plants to easily assemble and test each subsystem. One such architecture is a distributed multiplex arrangement that reduces the number of wires while enabling flexibility and expandability. Previous versions have had to deal with issues such as noise immunity at high switching currents. The LIN Bus with its low cost and rail-to-rail capability may be the key enabling technology to make the multiplexed architecture a reality.

Hybrid electric vehicles have the potential to reduce air pollution and improve fuel economy without sacrificing the present conveniences of long range and available infrastructure that conventional vehicles offer. Hybrid vehicles are generally classified as series or parallel hybrids. A series hybrid vehicle is essentially an electric vehicle with an on-board source of power for charging the batteries. In a parallel hybrid vehicle, the engine and the electric motor can be used to drive the vehicle simultaneously. There are various possible configurations of parallel hybrid vehicles depending on the role of the electric motor/generator and the engine. In this paper, a comparative study of the drivetrains of five different hybrid vehicles is presented. The underlying design architectures are examined, with analysis as to the tradeoffs and advantages represented in these architectures.

This paper describes the development and implementation of an Engine Drag Control algorithm to improve vehicle stability performance. Engine drag can occur on low and high coefficient surfaces when the driver suddenly releases the throttle. If the engine drag force becomes larger than the frictional force between the tire and the road, the tires will break loose from the surface and slip. This could induce vehicle instability especially with rear drive vehicles on low-coefficient surfaces. The EDC algorithm has been developed to provide accurate control of the wheels. EDC will help reduce the yaw rate of the vehicle and thus achieve greater vehicle stability. The paper also presents methods used to test the robustness of such a system. The purpose of the testing was to ensure that there would be no false activations of EDC under normal driving conditions and also to ensure that, when the system is active, it is mostly transparent to the driver.

This work examines the development and implementation of a pulsing brake control system as part of a Forward Collision Warning (FCW) System for an Adaptive Cruise Control (ACC) prototype vehicle. The brake pulse is a likely candidate to be employed with visual and auditory cues in the event of an imminent collision alert level when the driver is not in ACC mode.

As compared to home audio, the automobile has a different spatial and spectral distribution of sound. This can cause stereo images to blur or shift due to conflicting localization cues. The impact of interaural time and level differences is discussed, along with frequency-selective pinna and head cues. Review of the literature shows that our poorest localization is for mid frequencies (∼2kHz). Yet in an automobile, low frequencies are severely relocated with a minimum effect on fidelity. It is suggested this is because middle frequencies dominate the perception and localization of sound. Therefore, some high frequency information might also be relocated.