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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.

The lateral runout of disc brake corner components can lead to the generation of brake system pulsation. Emphasis on reducing component flatness and lateral runout tolerances are a typical response to address this phenomenon. This paper presents the results of an analytical study that examined the effect that the attachment of the wheel to the brake corner assembly could have on the lateral distortion of the rotor. An analysis procedure was developed to utilize the finite element method and simulate the mechanics of the assembly process. Calculated rotor distortions were compared to laboratory measurements. A statistical approach was utilized, in conjunction with the finite element method, to study a number of wheel and brake corner parameters and identify the characteristics of a robust design.

It is well known that the design of the seal groove assembly in the brake caliper greatly influences the braking performance. The rubber seal performs the dual function of sealing the piston bore and retracting the caliper piston after a brake apply. However, the seal function is affected by the configuration of the seal groove, as well as the friction at the piston/seal and groove/seal interfaces. The material properties of the rubber seal are also important design parameters. Issues such as fluid displacement, piston retraction, piston sliding force, and brake drag are some of the critical brake performance parameters that must be considered in every caliper seal-groove design. Presently, the brake caliper seal groove design is still based on empirical rules established mainly from past experience and its performance is achieved through prototype testing.

In the catalytic converter, the thermal conductivity of the insulation material (intumescent mat) placed between the ceramic catalyst and the metal shell is strongly dependent on the temperature, resulting in the solving of non-linear heat conduction equations. In this paper, the analytic solution for the steady heat flow in a cylinder with temperature dependent conductivity is given. Using this analytic solution for the mat and including convection and radiation at the converter skin, an analytical expression for calculating converter skin temperature is obtained. This expression can be easily incorporated in a Fortran code to calculate the temperatures.

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 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.

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.

A double dielectric barrier discharge reactor driven by an alternating voltage is a relatively simple approach to promote oxidation of NO to NO2 for subsequent reduction in a catalyst bed. The chemical performance of such a non-thermal plasma reactor is determined by its current and electric field behavior in the gap, and by the fraction of the current carried by electrons, because the key reactants which initiate the NO oxidation and accompanying chemical changes are produced there, mostly by electron impact. We have tried to determine by models and experiments the bounds on performance of double dielectric barrier reactors and guidelines for optimization. Models reported here predict chemical results from time-resolved applied voltage and series sense capacitor data.

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.

This paper documents the advantages of brake corner system modeling and simulation over traditional component analysis techniques. A better understanding of the mechanical dynamics of the disc-braking event has been gained through brake corner system modeling and simulation. Single component analyses do not consider the load transfer between components during the braking event. Brake corner system analysis clearly quantifies the internal load path and load transfer sequence between components due to clearances or tolerance variations in the brake assembly. By modeling the complete brake corner assembly, the interaction between components due to the contact friction loads and variational boundary conditions can be determined. The end result permits optimal design of brake corner systems having less deflection, lower stress, optimum material mass, and reduced lead-time for new designs.

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”.

Legal requirements and responsibility for the environment require improved recyclability of car components. This can be achieved by a reduction in the variety of materials used, which can be separated after use. This is being demonstrated for wiring harnesses using a new hook and loop based fastening system. Easier assembly and disassembly, elimination of fixation holes in the car body, and improved serviceability can lead to considerable cost reductions. Field experience on test cars will be available at a later date.

An algorithm for estimation of vehicle yaw rate and side slip angle using steering wheel angle, wheel speed, and lateral acceleration sensors is proposed. It is intended for application in vehicle stability enhancement systems, which use controlled brakes or steering. The algorithm first generates two initial estimates of yaw rate from wheel speeds and from lateral acceleration. A new estimate is subsequently calculated as a weighted average of the two initial ones, with the weights proportional to confidence levels in each estimate. This preliminary estimate is fed into a closed loop nonlinear observer, which generates the final estimate of yaw rate along with estimates of lateral velocity and side slip angle. Parameters of the observer depend on the estimated surface coefficient of adhesion, thus providing adaptation to changes in road surface coefficient of adhesion.

With ever more stringent CO2 emissions mandates, many automobile manufacturers are seeking the fuel economy benefits of diesel and lean-burn gasoline engines. At the same time the emissions standards that diesel and gasoline engines will have to meet in the next decade continue to reduce. Proposed solutions for meeting the stringent emissions standards all appear to have limitations, such as propensities to poisoning from sulfur, narrow operating temperature windows, and requirements for controls that give rapid rich excursions. Non-thermal plasma-catalyst systems have shown good performance in bench testing while being largely unaffected by these same issues. A two-stage system with a unique non-thermal plasma reactor combined with a zeolite-based catalyst has been constructed and shown to work over a wide temperature range.

Automotive wiring assembly design and manufacturing has evolved from a locally based business to a global business. It is common today to engineer the design of a wiring assembly in one region of the world, to manufacture it in a second region, and to assemble it into the vehicle in a third region. This creates a need for global collaboration, training and communications. Design for Manufacturability (DFM) is a tool that can aid in this, in developing common processes globally, and reducing the cost and design complexity of the product in the early design stages. To develop a global DFM process, an organization must develop and implement a strategy. This paper will review the approach that an automotive wiring assembly supplier adopted. It will enumerate the benefits of developing a global Design for Manufacturability process, selecting a champion, and using a twelve-step plan to integrate DFM into each region.

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.

The problem being investigated involves a noise-quality issue on a power steering application, when a sudden change of steering wheel angle generates an unwanted steering system noise or “Squawk.” This phenomenon is mostly observed during parking maneuvers, especially at lock positions and when the hydraulic fluid reaches a critical temperature on the specific application. The objective of the work to solve this noise-quality issue was to first identify the cause and then eliminate the Squawk noise. There were several constraints: No change could be made in the properties or type of hydraulic fluid used due to specification requirements; Steering wheel valve torsion bar characteristic (torque vs. angle) needed to be maintained within specification for ride and handling purposes; and, In addition to the mentioned constraints, a high capability of noise elimination generated by the production tolerances and dispersion has been considered.

Performance of two types of NOx adsorber catalysts, one based on Ba and the other based on Ba with alkali metals, was compared fresh and after thermal aging. Incorporation of sodium(Na), potassium(K) and cesium(Cs) into NOx adsorber washcoat containing barium significantly increases the NOx conversions in the temperature range of 350-600°C over that of the alkali metal free NOx adsorber catalysts. NOx performance benefit and HC performance penalty were observed on both engine dynamometer and vehicle tests for the “Ba+alkali metals” NOx adsorber catalysts. “Ba+alkali metals” NOx adsorber catalysts also demonstrate superior sulfur resistance with better NOx performance after repeated sulfur poisonings and desulfations over the “Ba based” NOx adsorber catalysts.

In this paper we discuss in detail an algorithm that addresses cylinder-to-cylinder imbalance issues. Maintaining even equivalence-ratio (ϕ) control across all the cylinders of an engine is confounded by imbalances which include fuel-injector flow variations, fresh-air intake maldistribution and uneven distribution of Exhaust Gas Re-circulation (EGR). Moreover, in markets that are growing increasingly cost conscious, with ever tightening emissions regulations, correcting for such mismatches must not only be done, but done at little or no additional cost. To address this challenge, we developed an Individual Cylinder Fuel Control (ICFC) algorithm that estimates each cylinder's individual ϕ and then compensates to correct for any imbalance using only existing production hardware. Prior work in this area exists1,2, yet all disclosed production-intent work was performed using wide-range oxygen sensors, representing cost increases.

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.