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The wheel speed and the slip are important signals for many modern automotive control systems. The performance of these systems strongly depends on the quality of the evaluated wheel speed and the slip. However, during car motion, especially during acceleration or braking, deflections of the flexibly mounted wheel suspension and of the tire disturb the measurement or rather the determination of these signals. In this paper an approach to increase the quality of the evaluated wheel-speed signal and the slip signal by considering these influences is introduced. The method considers the longitudinal motion of the wheel center, the tangential motion or rather the oscillations of the belt, the changing of the dynamic tire radius and the disturbances due to the angular motion of the wheel-speed sensor. To obtain the required kinematic values for the compensation, a mathematical model of the wheel suspension and of the tire is developed.

Should the U.S. Seek Alternatives to Alternative Fuels? This paper looks at the progress that alternative fuels have made in reducing the dependence on foreign oil, and also looks at other programs such as the Partnership for New Generation of Vehicles (PNGV) to see which is practical.

A hydrodynamic analysis is presented for the behavior of individual tire tread element on the smooth pavement covered with thin fluid film. For the conditions of a rigid element and time-dependent loading, a computationally-efficient method is proposed. Application of product method leads to transforming a transient integro-differential system of equations to a steady-state single differential equation to describe viscous hydroplaning. Results from the study show that this approach provides a fast and accurate methodology for modeling viscous hydroplaning.

The accuracy of the CRASHEX version of CRASH, which uses a Newtonian rather than a Cartesian treatment of impact, is compared with that of a substantially “original” version of CRASH, both evaluated with respect to EDSMAC computer simulations of the RICSAC series of staged, partially braked collisions; and with similar data for EDCRASH, as published but recomputed. Special problems inherent in treatment of impact with a stopped vehicle, quasi-head-on impact, failure to separate after initial impact, and spin truncated by side slap are discussed. Appropriate use of the statistical confidence interval in single-event reconstruction is also discussed, as are anomalies in previously published standard deviations for EDCRASH applied to the RICSAC data. The study shows that the Cartesian simplification incurs dominantly large errors, a finding not generally recognized. For complete and accurate reconstruction, Newtonian treatment, as now provided in CRASHEX, is requisite.

Responsiveness is one of the main characteristics of a brake booster. The design of a tandem booster, with its two boosting chambers, has a negative influence on high responsiveness. This report, using the CFD method for the air flow analysis, shows the way we found the most suitable air passage within the space of the given design of the current production tandem booster.

In the article, an overview of current starter motor technology and recent developments is given. One of the main targets is to reduce the starting system weight in order to minimize the gasoline consumption of the vehicle. A new generation of lightweight intermediate-gear permanent magnet starters together with an innovative electronic switch allows an electronically controlled starting process. The electronic systems controls the starting process resulting in improved reliability, reduction of starting noise, and thermal protection of the starter motor. The article concludes with an overview on the perspective of future developments in starting systems.

The cigarette lighter has served as the de facto standard connection for after-market devices for many years. It is prone to vibrational disconnects and is difficult to style into the vehicle. A new connection, designed under the auspices of the United States Council for Automotive Research (USCAR), has been endorsed by the after-market as a more reliable and more robust method of connection.

Due to the variety of consumer demands and government regulations, the number of systems and parts to meet automotive needs is growing remarkably. In order to design in limited vehicle space, the requirements for these components are becoming increasingly difficult to meet. Cruise control systems are not an exception. These systems require small packaging as well as mounting locations at any place without compromising vehicle speed controllability. We focused these points to develop a cruise control system which is compact, light weight, low cost, high performance and can be used for all types of passenger vehicles, compact car to light truck. By researching resin materials of the highest durability and ease of processing, and utilizing them where applicable, we succeeded in developing a cruise control unit which reduces the number of parts remarkably.

Today's laws require that specific diagnostic information be made available on all vehicles manufactured on or after 1994 and sold in the United States. This information is typically available to a portable test device (Scan Tool) that is by necessity, external to the vehicle under test. Since this tool is not a part of the vehicle, it's very nature indicates that it should be portable and battery operated. Usually it is connected to the test vehicle's required female J1962 connector. The interface must conform to the standard pin assignments as designated by the appropriate SAE document.

The infrared technology for ACC sensors has reached a high standard up til now, but there are still problems with the detection of some vehicles. The most important factors for low detection ranges are bad weather conditions and the state of the vehicle. In order to guarantee a reliable function of the sensor it's important to know about the reflection properties of the vehicles. In this diploma work the influence of different factors on the reflection properties of vehicles was investigated. The parameters, which were taken into regard, are the colour of vehicles, the geometry of the vehicle rear, the viewing angle and the contamination of vehicles. The measurements were made with a modified LEICA ODIN 3 sensor with a very small aperture of the laser beam. This modified sensor was mounted in two axes rotatable, that the rear of the cars could be scanned, to measure the reflected radiation in every point of the rear.

Technology and economics have limited the degree to which old automobiles are recycled. For environmental reasons, European governments have adopted policies that will increase that rate of recycling. However, contrasting the economic, political, and environmental situations in North America and Europe reveals that an automobile recycling policy for the U.S. would be superfluous, costly, and not significantly beneficial at this time.

The importance of friction between tire and road for the dynamic behavior of road vehicles has been emphasized in many publications. Continuously updated knowledge of the friction potential and the friction demand can help to improve maneuverability and thereby safety of vehicles under slippery road conditions. An on line estimation method, based on combination of side force and self aligning torque, generated by the tire, is theoretically founded on a simple brush type tire model. The system is implemented in the front wheel suspension of a passenger car. To cope with the highly non-linear behavior of the wheel suspension and the actual tire, various static neural networks have been applied in the estimation procedure. Experiments have been carried out both in simulation using a full vehicle multi-body model and with an actual vehicle. Conclusions are drawn regarding the estimation principle, the application of neural networks and the implementation in a test vehicle.

Solutions are being sought for the problem of overcrowding on the Nation's highway systems. Intelligent Transportation Systems (ITS) is being considered as a solution to this problem. Research and development of ITS started in the 1990's and is now reaching the deployment stage. The Federal government has been heavily involved in researching these technologies but is now considering its involvement in the deployment of ITS.

A rearward-facing infant restraint (RFIR) planned for use in the front seat of a vehicle equipped with a passenger-side airbag has been prototyped and subjected to crash tests under FMVSS 213 test conditions-- including a deploying passenger airbag and a CRABI 6-months old dummy. This RFIR design is discussed in detail, including energy management assumptions, design objectives, and the preliminary development testing. The RFIR prototype's design development test data are compared to a set of evaluation criteria. The results indicate the potential value of this rearward-facing infant restraint for controlling the motion, forces, and accelerations an infant could be exposed to during airbag/infant restraint interaction.

The purpose of this project was to develop and validate a computer-based version of the Belt Fit Test Device with a view towards exploring the potential of this technology to improve belt fitment for the general occupant population. The electronic BTD was initially developed and validated against two seats using the Transport Canada seat simulator. Preliminary validation indicated good correspondence between computed and measured BTD co-ordinates. The electronic BTD was then validated in ten vehicles. In total, 40 BTD scores were computed using the electronic BTD and compared with actual BTD values. In 30 of the 40 comparisons, the discrepancy between measured and computed values was less than one centimetre. In terms of test performance using the pass/fail criteria developed for the BTD, 37 of the 40 comparisons were in agreement. However, a number of refinements have been identified which could further improve the seat belt algorithm and the overall usefulness of the model.

We have developed a new Carbon/Carbon composite (C/C) manufacturing process called the “Carbon Powder Sintering Method [1] (C.P.S.M.)”. This study was conducted to evaluate the friction characteristics of C/C manufactured by the C.P.S.M. as compared with C/C manufactured by conventional methods using a dynamometer. In general, C/C shows a high friction coefficient at a high temperature, but shows a low friction coefficient at room temperature. There is a transition temperature point between both friction coefficients. As a result of this study, it was found that the transition temperature of the C.P.S.M. C/C is lower than for any other conventional C/C.

From a study of a large quantity of frictional data on elastomeric rotary lip seals of different designs operating under various test conditions, it has been possible to identify and quantify underlying similarities. Assuming the frictional coefficient comprises a Newtonian lubrication component and a dry or boundary friction one, the analysis allows these to be individually estimated. It has been found that these individual components have a good correlation to certain test parameters.

This paper discusses design parameters for automotive seats intended to simultaneously meet three design objectives: comfort, safety, and health. (“Health” refers to long-term spinal support and vibration attenuation.) For comfort, various ergonomic and human factors considerations are discussed ranging from seat dimensions and adjustments to cushioning and occupant perceptions of comfort. For safety, the principal consideration is the effectiveness of the seat in providing spinal support during accidents-particularly in rear-end collisions. An additional safety consideration is the ability of the seat to keep an occupant “in position” during an accident. Finally, for health concerns, the focus is upon maintenance of spinal stability, seat ergonomics, and road induced vibration attenuation. The paper presents design parameters satisfying these design objectives.

This paper reports test results of a compact, high pollutant conversion efficiency, catalytic muffler developed for utility engines (<19kW/25hp). Tests were conducted in-house, and at an independent laboratory under EPA supervision and funding, using a four-stroke engine generator set. The specific HC, CO and NOx emissions were reduced by 98%, 97%, and 19%, respectively. This level of reduction is thought to be sufficient for reducing such emissions from utility engines to the level of future standards such as 1999 CARB. A total of 200 hours of performance and limited durability testing were accumulated on the catalytic muffler. The prototype demonstrated successful operation by entraining fresh air and mixing with exhaust gas, converting pollutants, maintaining acceptable skin and exhaust gas temperatures, and muffling noise.

Packaging requirements to meet current and future exhaust legislations force automakers to use the given space either in the engine compartment or in underbody position as efficiently as possible. This requirement leads to substrate contours with wide ranges of different radii to fill the space with the recommended catalytic volume. Especially converters with race-track shaped substrates suffer from mechanical durability problems. They occure primarily in the region of the extreme wide radius due to erosion of the thermal expanding support mat. This is commonly known as mat erosion. A new approach to improve the durability of the substrate support system is a PatchWorkDesign support mat, which combines the advantages of an alternative fibre mat with those of the intumescent mat.