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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.

Side impact accounts for a significant source of societal harm, injury and death. To address this issue, Europe and US have introduced legislation to be met for the new vehicle certification. In an effort to meet these regulations and the market demand for safety, Automotive manufacturers have significantly improved vehicle side structure integrity and introduced side impact airbags are for added protection. Today, passenger vans, light truck and sport-utility type vehicles are all popular consumer choices in the US. These vehicles differ significantly from passenger cars in many respects and as such need special design considerations for side airbags. Here, MADYMO-3D model of a generic passenger van / Sport-Utility type vehicle is created and correlated to FMVSS-214 side impact crash test. This model is used to evaluate both door and seat mounted side airbag designs in different orientations at standard test impact condition and at a higher speed.

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.

Many companies around the world have adopted the lean thinking as their strategy to operate, in a global market where changes happen all the time. One foundation for the success of lean manufacturing appliance is the continuous improvement approach which has been considered even on company statements, or it can be also considered as part of the genetic code of any enterprise. However, if in one side the continuous improvement thinking, set people mind to look for opportunities of improvement all the time, on other hand these improvements are incremental and they do not have significant impact on company performance on both short-term and medium-term and sometimes, the activities performed by the employees are not sustainable due to the lack of structure to manage and follow up these activities.

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.

Seat belts are the primary occupant-protection devices for vehicle crashes. Field statistics show that proper usage of seat belts substantially contributes to decreases in the fatality rate and injury level. To collect first-hand information regarding seat belt comfort and usability, a questionnaire survey was conducted. The most significant problems were found as belt trapping in the door, awkward negotiating with clothes, belt twisting, belt locking up, and difficulty to locate the buckle. The survey results indicated that drivers who are over 40 years old have more complaints than younger drivers. When the driver's age increases to 55 and above, belt pulling force and inappropriate and loose fitting of the belt on the body become major issues. Female drivers have more complaints than male drivers. Short statured drivers need both hands to pull and guide the retracting of the belt.

In this study, US and UK accident data were analyzed to identify parameters that may influence rollover propensity to analyze driver injury rate. The US data was obtained from the weighted National Automotive Sampling System (NASS-CDS), calendar years 1992 to 1996. The UK pre-roll data was obtained from the national STATS 19 database for 1996, while the injury information was collected from the Co-operative Crash Injury Study (CCIS) database. In the US and UK databases, rollovers accounted for about 10% of all crashes with known crash directions. In the US and UK databases, most rollovers occurred when the vehicle was either going straight ahead or turning. The propensity for a rollover was more than 3 times higher when going around a bend than a non-rollover. In the UK, 74% of rollovers occurred on clear days with no high winds and 14% on rainy days with no high winds. In the US, 83% of rollovers took place in non-adverse weather conditions and 10% with rain.

In this study, U.S. accident data was analyzed to determine interior contacts and injuries for front-seated occupants in rollovers. The injury distribution for belted and unbelted, non-ejected drivers and right front passengers (RFP) was assessed for single-event accidents where the leading side of the vehicle rollover was either on the driver or passenger door. Drivers in a roll-left and RFP in roll-right rollovers were defined as near-side occupants, while drivers in roll-right and RFP in roll-left rollovers were defined as far-side occupants. Serious injuries (AIS 3+) were most common to the head and thorax for both the near and far-side occupants. However, serious spinal injuries were more frequent for the far-side occupants, where the source was most often coded as roof, windshield and interior.

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.

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.

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.

Today automotive system suppliers develop more-or-less independent systems, such as brake, power steering and suspension systems. In the future, car manufacturers like Volvo will build up vehicle control systems combining their own algorithms with algorithms provided by automotive system suppliers. Standardization of interfaces to actuators, sensors and functions is an important enabler for this vision and will have major consequences for functionality, prices and lead times, and thus affects both vehicle manufacturers and automotive suppliers. The investigation of the level of appropriate interfaces, as part of the European BRAKE project, is described here. Potential problems and consequences are discussed from both a technical and a business perspective. This paper provides a background on BRAKE and on the functional decomposition upon which the interface definitions are based. Finally, the interface definitions for brake system functionality are given.

The purpose of this paper is to evaluate through simulations the effects of active chassis systems on vehicle propensity to rollover caused by aggressive handling maneuvers. A 16 degree-of-freedom computer model of a full vehicle is used for this purpose. It includes models of active chassis systems and the associated control algorithms, and allows for simulation of vehicle dynamic behavior under large roll angles. The controllable chassis systems considered in this investigation are active rear steer, brake based vehicle stability enhancement system and active anti-roll bar. The maneuvers used in simulation are the double lane change and the fishhook maneuvers with increasing steering amplitudes. The vehicle represents a midsize SUV with a marginal static stability factor of 1.09 and aggressive tires. The results of simulations demonstrate that the uncontrolled vehicle rolls over in both maneuvers when the steering angle is sufficiently large.

The focus of this study is to validate the predictive capability of a recently developed physiology based thermal comfort modeling tool in a realistic thermal environment of a vehicle passenger compartment. Human subject test data for thermal sensation and comfort was obtained in a climatic wind tunnel for a cross-over vehicle in a relatively warm thermal environment including solar load. A CFD/thermal model that simulates the vehicle operating conditions in the tunnel, is used to provide the necessary inputs required by the stand-alone thermal comfort tool. Comparison of the local and the overall thermal sensation and comfort levels between the human subject test and the tool's predictions shows a reasonably good agreement. The next step is to use this modeling technique in designing and developing energy-efficient HVAC systems without compromising thermal comfort of the vehicle occupants.

This paper investigates a method for improving vehicle stability by incorporating feedback from a yaw rate sensor into an electric power steering system. Presently, vehicle stability enhancement techniques are an extension of antilock braking systems in aiding the driver during vehicle maneuvers. One of the contributors to loss of vehicle control is the reduction in tactile feedback from the steering handwheel when driving on wet or icy pavement. This paper presents research indicating that the use yaw rate feedback improves vehicle stability by increasing the amount of tactile feedback when driving under adverse road conditions.

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.

It is well known that hydrocarbon reduction during a cold start is a major issue in achieving ultra low emissions standards. This paper describes one of the possible approaches for reducing the cold-start hydrocarbon emissions by using a fast “light-off” planar oxygen sensor. The goal of this study was to verify the operation characteristics of Delphi's fast “light-off” planar oxygen sensor's (INTELLEK OSP) operating characteristics and the closed-loop performance for achieving improved hydrocarbon control for stringent emission standards. Tests were conducted in open-loop and closed-loop mode under steady and transient conditions using a 1996 model year 2.4-liter DOHC in-line 4-cylinder engine with a close-coupled catalytic converter. Overall performance of the OSP showed relatively quick reaction time to reach the operating temperature.

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.

Vehicle interior harmony has drawn increasing attention from customers in recent years. Kansei Engineering is an effective approach to quantify the relationship between design parameters and customer perceptions of the product. This article is a continuation of our previous study on commercial truck interior harmony. Herein, we investigated the customer perception of the visual aspects of commercial truck door interior design using classification methods. This article describes how these visual impressions are related to design elements using quantification theory, a commonly used method in Kansei Engineering. The results reveal that trim material, shape, color, window shape, and map pocket are design elements that strongly affect the perception of elegance and preferences of truck drivers. The results also showed a significant difference between the perception of the truck drivers and design engineers.

Automotive occupant safety continues to evolve. At present this area has gathered a strong consumer interest which the vehicle manufacturers are tapping into with the introduction of many new safety technologies. Initially, individual passive devices and features such as seatbelts, knee- bolsters, structural crush zones, airbags etc., were developed for to help save lives and minimize injuries in accidents. Over the years, preventive measures such as improving visibility, headlights, windshield wipers, tire traction etc., were deployed to help reduce the probability of getting into an accident. With tremendous new research and improvements in electronics, we are at the stage of helping to actively avoid accidents in certain situations as well as providing increased protection to vehicle occupants and pedestrians.