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Continued development of Reinforced Reaction Injection Molding (RRIM) polyurea polymers for toughness, blister resistance and large-part processing as exterior vertical body panels has launched ELPO-compatible exterior outers into automotive assembly-line operations. This allows automotive OEM design to take advantage of the unique molding shapes for side outers and fenders while reducing weight, assembly (DFA) and time/operations costs (DFM). Polyurea RRIM body panels have been successful in meeting the demanding auto industry requirement for lightweight, damage-resistant exterior outer panels as an economical alternative to steel. Design freedom advantages, low prototype cost and tooling savings through predictive modelling have allowed the commercial use of RRIM body panels. This high-temperature-resistant polyurea RRIM composite allows on-line painting, including passing through the steel corrosion protection primer (E-coat) cure environments.

A new RRIM system produces a polyurea polymer that is capable of going through a traditional assembly process including E-coat bakes of up to 200C. In order to achieve the necessary performance characteristics, the high temperature resistant polyurea RIM polymer requires post-cure temperatures between 180C and 200C. Existing ovens are designed to post-cure materials below 160C. Also, existing ovens may not be large enough to handle pickup truck rear fenders. The existing ovens need to be refurbished or new ones built to meet the new market demand. To reduce the cost of the post-cure process, infrared (IR) radiation was tested to determine its utility for post-curing RIM parts. It was demonstrated that a infrared radiation can be used to pre-heat the RIM part in 1/10th the time of a convection oven in the laboratory. The benefit of using infrared radiation is improved dimensional stability and impact properties with acceptable flexural modulus.

This paper documents the design methodology, part performance, and economic considerations for a generic hardware module applied to a front passenger-car door. Engineering thermoplastics (ETPs), widely used in automotive applications for their excellent mechanical performance, design flexibility, and parts integration, can also help advance the development of modular door-hardware systems. Implementation of these hardware carriers is being driven by pressures to increase manufacturing efficiencies, reduce mass, lower part-count numbers, decrease warranty issues, and cut overall systems costs. In this case, a joint team from GE Plastics, Magna-Atoma International/Dortec, and Excel Automotive Systems assessed the opportunity for using a thermoplastic door hardware module in a current mid-size production vehicle. Finite-element analysis showed that the thermoplastic module under study withstood the inertial load of the door being slammed shut at low, room, and elevated temperatures.

With the total amount of air pollution caused by vehicle emissions on the increase, the problem has now became a global concern, and various regulatory measures have been put into effect in each region of the world. This is especially true in California, U.S.A, where countermeasures have been adopted early. There, the ULEV (Ultra Low Emission Vehicle) standard, which was ones deemed impossible for gasoline engines to meet, is now in effect. In response to these developments, Honda announced the ULEV system for a 2.2 liter gasoline engine with a closed-coupled catalytic converter (CC) and an under-floor catalytic converter (UF) at the beginning of 1995, and reported on the system's emission characteristics. 1) A new ULEV system has been developed based on the previous system but using only UF, aiming for marketable improvements in product characteristics such as higher output. The new system features the ultra low heat capacity and high heat insulating (ULOC) exhaust manifold.

The first generation of interstitial-free or ultra-low carbon (ULC) sheet steels has good drawability but very low yield strength. The second generation of ULC steels contains high phosphorus and/or allow a partial stabilization of carbon. However, traditional alloy design does not always result in the desired properties. This paper reviews new understanding of the precipitation and mechanical behaviors of ULC steels.

Automotive design engineers consistently are presented with challenges in the decorating, labeling, marking, and/or coding of automotive components made from thermoplastic and thermoset polymer materials. Exterior components, such as fascias; interior components, like plastic console buttons and radio panels; and underhood components, such as covers for fuse busses and fluid reservoirs, can present production and performance challenges because of the difficulties associated with making decorative or informational marks on them that maintain durability during the expected life of a vehicle. Many of these parts are small, yet represent a disproportionate design and production cost, incurred through the development and implementation of procedures used for marking them. The automotive industry has used improved techniques, such as laser marking technology, in its attempts to inscribe more permanent and comprehensive markings on critical parts.

This paper discusses the contribution of instrument panel systems in a European side-impact event. Systems studied include a conventional steel cross-car beam system and a glass-mat thermoplastic (GMT) composite system, evaluated in a body-in-white structure. A thermoplastic composite instrument panel system offers mass, cost, and recycling benefits, but its performance vs. a conventional steel cross-car beam system merited an engineering investigation. The comparison methodology used included a nonlinear dynamic side impact study with a moving, deformable barrier developed according to European Economic Community (EEC) standards. A finite-element model used in this study simulated the body-in-white structure, barrier structure and instrument panel systems. The resulting data include velocity, displacement and energy absorption levels of various components of the respective instrument panel systems.

This report presents the results of the driver's field of view and the performance of six crossview and two sideview mirror systems on a conventional long-nosed school bus. It also contains an evaluation of the image quality of the crossview mirrors in terms of the angular length and width of their reflected images. The measurements of the field of view and the evaluation of image quality were done at two driver eye locations, one representative of the cyclopian view of a 95th percentile adult male and the other one representative of the cyclopian view of a 5th percentile adult female. Measurements were taken considering that there were no head movements. For the purposes of the study, the term “blind spot” was defined as meaning any area that could not be seen directly by the driver. The performance of the mirrors was judged in terms of their capacity to provide a complete and clear view of the blind spots.

A correlation between engine dynamometer- and vehicle-aged catalysts has been established for novel lean-burn applications. A lean-burn, 1.8-L Ford Mondeo with a close-coupled three-way catalyst and an underfloor lean-NOx trap was used for this study. Vehicle aging of the emissions control system was done using a prescribed driving schedule. Engine dynamometer aging was done using a four-event aging cycle modified for lean-burn applications. The two aging methods were compared using maximum NOx conversion efficiencies measured during a two-mode dynamometer evaluation cycle. It was found that 75 h of four-event dynamometer aging is equivalent to 80,500 km of prescribed vehicle driving.

Copper ion-exchanged X-zeolite with urea infusion was tested for nitrogen oxide (NOx)conversion efficiency in this study. Temperature datapoints were obtained to arrive at peak activation temperatures. Variation of the air/fuel ratio showed the widening of the λ-window(the range of air-fuel ratios over which the NOx conversion efficiency is considerable); a maximum of 62% NOx conversion efficiency was obtained in the lean-burn range. Effects of space velocity variations were also observed. In order to minimise the deactivation of zeolite caused by water, ammonium carbonate and ammonium sulphate were deposited on the copper ion-exchanged X-zeolite and the corresponding NOx conversion efficiencies measured. Ammonia slip (leakage of unreacted ammonia), a prospective pollution hazard, was observed to be more in case of urea infusion than ammonium salt deposition at higher temperatures.

The emissions performance of catalytic converters under different conditions of flow distribution was investigated. Computational Fluid Dynamics methods were utilised to model the maldistribution effects of different inlet cones. The effects of maldistribution on ageing, light-off and conversion were investigated using steady state tests on an engine bench. Emission testing was also conducted on a vehicle throughout ECE and EUDC test cycles. Maldistribution was found to have a significant effect on the efficiency of the catalyst during the early stages of the ECE cycle for both fresh and aged catalysts. The effects were less significant over later stages of the ECE cycle and throughout the EUDC except NOx where maldistribution did have an effect on the conversion at higher flow rates during the later stages of the test.

Variability in dummy response causes problems when developing a vehicle structure or a restraint system for side impact crashworthiness. A study has been carried out with the objective of quantifying the response variation experienced by the EuroSID, BioSID and USSID dummies, due to dummy positioning and the door velocity time history. MADYMO 3D was used to generate a door trim profile from a 4-door saloon vehicle, and the dummy data was imported from the MADYMO dummy database. A velocity profile from the intruding door was taken from a European ECE 95 side impact crash test, and the three dummy models were then correlated to side impact (M-SIS)(1) sled test results. Design of Experiment techniques were used to develop a three dimensional positioning matrix, which enabled information to be obtained efficiently, but with a minimum number of simulations.

The Double Objective variant of the Milner mirror represents the latest evolution of a family of designs developed from the original 1989 Milner prismatic exterior rear view mirror configuration. Papers reviewing this design evolution are referenced. In Double Objective form, the Milner mirror concept has attained a maturity of packaging and function that further enhances its appeal as an OEM system to both the auto makers and their suppliers. The paper briefly reviews other Milner mirror family members before describing the particular constructional and functional features of the Double Objective system in greater detail.

Automotive rearview mirrors have numerous attributes that render them desirable hosts for a variety of added features beyond their principal function of providing a rearview field of vision. One attribute is location. The driver frequently looks at rearview mirrors as part of the normal driving task, and thus they are ideal locations for information display such as of directional information from a compass sensor and/or of temperature information from an exterior temperature sensor. Icons and indicia displaying status of, for example, passenger airbag enable/disable, are readily viewable by the driver when displayed at an interior rearview mirror or exterior sideview mirror. Rearview mirrors are desirable locations for automatic wiper activation rain sensors, automatic headlamp activation controllers, remote keyless entry receivers, garage door opener/home access transmitters, and antennae such as for global positioning satellite (GPS) systems.

The outside rear view mirrors on motor vehicles are located outside a vehicle's solid body, normally attached to the side doors. Owing to their contour and positions, they present certain drawbacks which may cause dangers on the road, especially under unfavorable conditions when both the side door glasses and the surface of the outside mirrors are contaminated. An advanced optic rear view mirror unit has been designed and developed, with the aim to eliminate all the drawbacks of said outside rear view mirrors and hence to enhance the traffic safety. It shows that the said mirror unit eliminates the aerodynamic drags and sight blocks caused by the protrusion of conventional outside mirror bodies, places the rear vision inside a vehicle at a more logical physical position related to the driver, and provides an always clear view to the rear area regardless the outside weather conditions.

The airbag systems in the first generation had been developed and are equipped in real automobiles. This paper is aimed at describing a new airbag scheme that might be categorized in the 1.5 generation. The airbag system always needs some delay time between the triggering and complete expanding. The existence of the delay time is the main cause of difficulty for accurate airbag triggering. The predictive airbag expanding algorithm that compensates the delay time was proposed and the validity was examined in the first generation development. Development of the 1.5 generation airbag systems with the higher performance are our next problem. Airbag equipped in automobiles must receive driver's body at the optimal timing when collision by which the effect of airbag is extremely improved. The more accurate predictive airbag system is required.

Based on the theory of multibody system dynamics, some characteristics of the Mcpherson independent suspension (Audi 100 front suspension) are analyzed. The planar and spatial models consisting of multiple closed-loop systems with rigid and deformable bodies are included in the study. In the planar analysis, Lagrange method is used to develop dynamic equations. In the spatial analysis, a special and practical method to transform system stiffness to the wheel center is used to simplify the calculation process and obtain the satisfactory results more easily. As an example, a result of turning behavior is given to show that the method introduced is effective to investigate some effect of the parameters of the suspension on car performance. Specialized test techniques are implemented to obtain the mechanical property of the components which is necessary in the analysis.

NHTSA conducted seventy-six side impact FMVSS No. 214 compliance tests from 1994 through 1997. The compliance tests are nearly right angle side impacts with low longitudinal components of change of velocity (Δv). Frontal air bag deployments were found to have occurred for 34% of the driver bags and 32% of the front passenger bags in these compliance-tested passenger cars. In 1997, NHTSA began testing passenger cars 'in side impact in the New Car Assessment Program (NCAP). The NCAP crash tests are conducted at a higher speed than the compliance tests. The cars in the NCAP side impact tests also had low longitudinal components of Δv. Approximately 40% of the twenty-six passenger cars tested in the 1997 Side Impact NCAP had their frontal air bags deploy. Real world crash data were examined to determine if frontal air bags are deploying in right angle side impacts on the roads of the US.

This paper addresses issues associated with the measurement and analysis of crank angle based cylinder pressure to obtain accurate knock data. Issues examined include knock model features, the effect of sample size, the impact of sampling frequency, optimum knock windowing and the influence of transducer in-cylinder location and mounting arrangement. The study has demonstrated that a very large sample size is required to obtain good repeatability and at least 1000 engine cycles is recommended for knock intensity determination. A knock window of TDC to TDC+40 degrees has been shown to be appropriate whilst a 0.2 degree crank angle resolution is considered to be adequate for the knock algorithm employed. This work has also confirmed that transducers should have high natural frequency, be flush mounted to avoid cavity resonance and that knock signals can be significantly influenced by transducer location.

The purpose of this study was to demonstrate a method to improve the handling performances of a vehicle through the sensitivity and quasi-static analysis validated by the K&C test. The design changes were needed to reduce the understeer tendency of the vehicle. The sensitivities of the hard points for the target suspension parameters, were calculated using SDAP (Suspension Design Analysis Program). The hard points were changed based on these sensitivity values. In order to foresee the handling performances of the changed vehicle, the suspension parameters were calculated using ADAMS/ vehicle. Finally the handling performances of the new designed vehicle were simulated through the full vehicle analysis using ADAMS, compared with those of the original one.