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Steer-by-wire and other “by-wire” systems (as defined in the paper) offer many passive and active safety advantages. To help ensure these advantages are achieved, a comprehensive system-safety process should be followed. In this paper, we review standard elements of system safety processes that are widely applied in several industries and describe the main elements of our proposed analysis process for by-wire systems. The process steps include: (i) creating a program plan to act as a blueprint for the process, (ii) performing a variety of hazard analysis and risk assessment tasks as specified in the program plan, (iii) designing and verifying a set of hazard controls that help mitigate risk, and (iv) summarizing the findings. Vehicle manufacturers and suppliers need to work together to create and follow such a process. A distinguishing feature of the process is the explicit linking of hazard controls to the hazards they cover, permitting coverage-based risk assessment.

This paper first reports on the benchmarking of a gasoline- fueled vehicle currently for sale in California that is certified to ULEV standards. Emissions data from this vehicle indicate the improvements necessary over current technology to meet SULEV tailpipe standards. Tests with this vehicle also show emissions levels with current technology under off-cycle conditions representative of real-world use. We then present Delphi's strategy of on-board partial oxidation (POx) reforming with gasoline-fueled, spark-ignition engines. On-board reforming provides a source of hydrogen fuel. Tests were run with bottled gas simulating the output of a POx reformer. Results show that an advanced Engine Management System with a small on-board reformer can provide very low tailpipe emissions both under cold start and warmed-up conditions using relatively small amounts of POx gas. The data cover both normal US Federal Test Procedure (FTP) conditions as well as more extreme, off-cycle operation.

TPO is getting wider acceptance for automotive applications. An exterior application like a fascia is a very good example. Interiors are still a challenge due to many reasons including overall system cost. For interior applications, “all-olefin” means it mainly consists of three materials: TPO skin, cross-linked olefinic-based foam and PP substrate. The driving force for TPO in Europe is mainly recyclability while in the USA, it is long-term durability. This paper describes the key limitations of the current TPO systems which are: poor grain retention of TPO skin, shrinkage in-consistency of the skin, high cost of priming (or other treatments) and painting of the skin, lower process window of the semi-crystalline TPO material during thermoforming or In-mold lamination / Low pressure molding, high cost of the foam, low tear strength of the foam for deep draw ratio etc.

The solid oxide fuel cell (SOFC) system has emerged as an important technology for automotive and stationary applications. Modeling and simulation of the SOFC system have been utilized as an integral tool in an accelerated joint SOFC system development program. Development of unique modeling approaches and their results are discussed and compared with experimental performance. One dimensional system level analysis using Aspen with an embedded stack electrochemical model was performed resulting in effective sub-system partitioning and requirements definition. Further, a three-dimensional integrated electrochemical / thermal / computational fluid dynamics analysis of steady-state operation was employed. The combination of one-dimensional and three-dimensional environments led to effective performance projection at all levels in the system, resulting in optimization of overall system performance early in the design cycle.

With new legislation and federal regulation for vehicle emission levels, automotive and truck manufacturers have been prompted to focus on emission control technologies that limit the level of exhaust pollutants. One of the primary pollutants, especially from diesel engines, is oxides of nitrogen (NOx). One possible solution to this pollution challenge is to design a more efficient internal combustion engine, which would require better engine operating parameter controls. However, there are limitations associated with such tight engine management. This need has led researchers and engineers to focus on the development of exhaust aftertreatment devices that will reduce NOx emissions with current diesel engines. An optimum aftertreatment device must be unaffected by exhaust-gas impurity poisoning such as sulfur products, and must have minimal impact on vehicle operations and fuel economy.

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.

The automotive industry is moving to a higher voltage for the electrical system. This change will occur because the total electrical power required by the vehicles will increase to a level where the current requirements at 14 volts will be impractical. Some of the new loads will change the duty cycle of the battery. The most notable change is the proposed start/stop mode of vehicle operation where the engine is stopped and restarted frequently to avoid prolonged operation at idle. An additional feature would be to use an electric motor to assist in acceleration and/or to actually launch the vehicle. This paper addresses the changes in battery requirements brought on by these new features. A means of analysis for choosing the appropriate battery technology is presented. We also propose a life test to establish a benchmark for current battery technology when it is used in a new duty cycle.

A high pressure outwardly opening fuel injector has been developed to produce sprays that meet the stringent requirements of gasoline direct injection (DI) combustion systems. Predictions of spray characteristics have been made using KIVA-3 in conjunction with Star-CD injector flow modeling. After some modeling iterations, the nozzle design has been optimized for the required flow, injector performance, and spray characteristics. The hardware test results of flow and spray have confirmed the numerical modeling accuracy and the spray quality. The spray's average Sauter mean diameter (SMD) is less than 15 microns at 30 mm distance from the nozzle. The DV90, defined as the drop diameter such that 90% of the total liquid volume is in drops of smaller diameter, is less than 40 microns. The maximum penetration is about 70 mm into air at atmospheric pressure. An initial spray slug is not created due to the absence of a sac volume.

A method of canceling unknown angular rate effects in impact immunity measurement for angular rate sensors is presented. A pair of the same type of testing sensors is arranged such that the sensing axes of the sensor pair are 180° out of phase. While an angular rate produces anti-phase component in the sensor outputs, a linear acceleration produces in-phase response from the sensors due to similar mechanical symmetry. This phase difference is used to cancel the angular rate component even though the actual angular rate may still be unknown. This cancellation can be derived from the sensor output transfer function and is supported with our experimental data.

This paper describes the technique of in-cylinder ionization sensing in a common rail diesel engine. The technology detects in real time, the start of combustion for both pilot and main combustion enabling the fuel control strategy to change from open to closed loop, thus, maintaining the desired start of combustion for all speeds and loads. Additionally, the ionization sensing enables the ECM to truly correct for changes in ignition delays caused by as an example a change in fuel cetane number or in air, fuel and engine temperature. The conclusions are that ionization sensing improves the ability to control a diesel engine and is a feasible technology for production vehicles.

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.

The interdependence of consumer features, new electronic and electrical architectures and hybrid propulsion systems are examined. There are two major forces driving future vehicle electronic and electrical systems, one is consumer demand for comfort and safety, and two is the demand for reduced fuel consumption and emissions. These forces are linked by the use of electronics to control vehicle energy generation and usage while providing managed solutions to these demands. Automobile consumer features are discussed and the case is made that these features will require more electric power to be installed on the vehicle. The presence of this increased electric power will then enable the hybrid vehicle functions that will benefit fuel economy and emissions performance.

Today, electrical/electronic systems like ABS/power brakes and electric power steering are all designed to enhance, not replace a mechanical function. If an electrical or electronic fault occurs, the function reverts to the base mechanical capability. Future E/E systems, such as steer-by-wire and brake-by- wire replace mechanical linkages with electrical or optical signals as in computer networks. While these systems offer many potential safety benefits, they will require different strategies for dependability, and as with any vehicle system, they will further require that dependability be an integral part of the overall E/E system design. This paper illustrates how by-wire systems drive different dependability requirements and discusses some key technologies that are emerging to meet these requirements.

Compromises inherent with fixed valve lift and event timing have prompted engine designers to consider Variable Valve Actuation (VVA) systems for many decades. In recent years, some relatively basic forms of VVA have been introduced into production engines. Greater performance and driveability expectations of customers, more stringent emission regulations set by government legislators, and the mutual desire for higher fuel economy are increasingly at odds. As a solution, many OEM companies are seriously considering large-scale application of higher function VVA mechanisms in their next generation vehicles. This paper describes the continuing development progress of a mechanical VVA system. Design features and operation of the mechanism are explained. Test results are presented in two sections: motored cylinder head test data focuses on VVA system friction, control system performance, valve lift and component stress.

Recent advances in dependable embedded system technology, as well as continuing demand for improved handling and passive and active safety improvements, have led vehicle manufacturers and suppliers to actively pursue development programs in computer-controlled, by-wire subsystems. These subsystems include steer-by-wire and brake-by-wire, and are composed of mechanically de-coupled sets of actuators and controllers connected through multiplexed, in-vehicle computer networks; there is no mechanical link to the driver. This paper addresses fundamental benefits and issues of steer-by-wire, especially those related to automated vehicle control and steering feel quality as perceived by the driver.

Delphi is developing a new combustion technology called Gasoline Direct-injection Compression Ignition (GDCI), which has shown promise for substantially improving fuel economy. This new technology is able to reuse some of the controls common to traditional spark ignition (SI) engines; however, it also requires several new sensors and actuators, some of which are not common to traditional SI engines. Since this is new technology development, the required hardware set has continued to evolve over the course of the project. In order to support this development work, a highly capable and flexible electronic control system is necessary. Integrating all of the necessary functions into a single controller, or two, would require significant up-front controller hardware development, and would limit the adaptability of the electronic controls to the evolving requirements for GDCI.

It is estimated that in the United States, nearly one quarter of all fatal automobile accidents involve a vehicle rollover. [1] In order to reduce fatalities and serious injuries, it is desirable to develop a sensing system that can detect an imminent rollover condition with sufficient time to activate occupant safety protection devices. The goals of a Rollover Sensing Module (RSM) are; 1 To accurately estimate vehicle roll and pitch angles 2 To reliably predict in a timely manner an imminent rollover 3 To eliminate false activation of safety devices 4 To function properly during airborne conditions 5 To be as autonomous as possible, not requiring information from other vehicle subsystems.

Electric power steering (EPS) is an advanced steering system that uses an electric motor to provide steering assist. Being a new technology it lacks the extensive operational history of conventional steering systems. Also conventional systems cannot be used to command an output independent of the driver input. In contrast EPS, by means of an electric motor, could be used to do so. As a result EPS systems may have additional failure modes, which need to be studied. In this paper we will consider the requirements for successful EPS operation. The steps required to develop diagnostics based on the requirements are also discussed. The results of this paper have been implemented in various EPS-based programs.

In recent years, the desire for improved vehicle performance, reliability and safety have increased the electrical content and its complexity in vehicles. Advanced automotive systems integrate sensors, controllers, actuators and communication networks. To maintain safety and reliability, a comprehensive system of diagnostics and physical and analytic redundancy are used. In some cases, diagnostic strategies based on analytical redundancy can provide detection, as well as fault-tolerance, and may provide benefits in cost, packaging, flexibility and reusability. This paper discusses a range of diagnostic methods and their applicability to advanced automotive systems such as X-by-Wire. It will also show the reduction to practice of an advanced analytical technique for an automotive application.

The purpose of this paper is to investigate occupant injuries which may be sustained during a single-event crash with known roll mechanism. The data was obtained from the weighted National Automotive Sampling System/ Crashworthiness Data System (NASS-CDS) for calendar years 1992 to 1996. The effect of number of rollover turns, roll direction, ejection and belt usage on driver injury responses was analyzed in single-event trip-overs. Trip-overs were chosen for the analysis because they account for over 50% of rollover crashes. The number of rollovers was divided in 3 categories: ¼ to ½ turn, ¾ to 1 turn and above 1 turn. Roll direction was either roll-left or a rollright along the longitudinal axis of the vehicle. Roll-left represents a roll with the driver side leading, while a roll right is with the right front passenger side leading. In the database used in this study, there were three times more belted drivers than unbelted.