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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.

About ten years ago the major noise and vibration sources in a vehicle were the engine and the aero dynamic noise sources. During these last years the noise and vibration levels induced in the vehicle by these two sources have decreased in very high proportions. The consequence of that is that former secondary noise sources like the air-conditioning system have now become major noise and vibration sources. One of the most important noise and vibration sources in the air-conditioning unit is the blower. This component is composed of an electric motor, a fan wheel and a motor support in which the electric motor is fixed. This work only deals with the vibrations generated which are due either to the wheel unbalance or due to electric motor vibrations. The unbalance can generate vibration discomfort on the steering wheel and the electric motor vibrations are very often solid borne noises generated especially for low speeds of operation.

To be an assistance for the driver and make his journeys more comfortable are the aims of the first “ACC” (Adaptive Cruise Control). It is the first step of a new area for the automotive future. ODIN is the name of the ACC-sensor made by ADC GmbH Switzerland, which based on infrared light (IR). There are full of parameters to describe the situation in front of a vehicle. Developing an ACC-sensor, needs to define this parameters exactly. What are the requirements? This will be discussed in the first section of the lecture. The near IR is out from research and already a cheap and reliable technology. Due to the close relation between the visible light the IR technology is predestinated for an forward looking sensor. The differences between other technologies will be illustrated. ODIN has been quite a success for many ACC application at the automotive industry. ADC still improve their knowledge and wants to present how we come up to the requirements of ACC.

Compression rings for heavy duty diesel engines are traditionally made of ductile cast iron material. These rings, in general, have conservative standard dimensions limited by the strength of their base material. More recently, however, the market for heavy duty diesel engines demanded products able to cope with high levels of power density and, at the same time, lower levels of oil consumption, friction, and emissions. This paper discusses the advantages of some radical changes made on the design of compression rings in order to take advantage of steel as the base material. The superior mechanical properties of steel allow the use of rings with smaller cross sections which minimizes the friction losses caused by the combustion gas pressure pushing the ring against the liner. It also allows the use of compression rings with a free gap significantly larger than usual.

Diesel engines are used in heavy duty applications because of their high efficiency and reliability. However, their high diesel particulates and NOx emissions remain major concerns. An eight cylinder direct injection diesel engine was connected to a partial flow particulate sampling mini-dilution tunnel. Six different grades of diesel fuels were studied for their regular emissions as well as smoke and particulate emissions. Each fuel was tested at three engine speeds and full load. This paper presents the results of these tests which includes analysis of the effects of load, cetane number, 90% distillation temperature, and density for steady state conditions. A correlation was developed for converting smoke numbers in Hartridge Smoke Units (HSU) to the specific particulate emissions by evaluating results of all fuels tests. Another correlation was also developed for diesel particulates and NOx emissions trade-off.

The comparison of a light weight crankcase to the production cast iron crankcase of the new Mercedes Benz 2.9-liter direct injection (DI) five-cylinder turbo diesel engine with intercooler is described. The light weight crankcase is cast from the aluminum alloy A 356 while other engine components like oil pan, timing case cover and brackets are manufactured from a magnesium alloy. This paper describes the engine design with the simultaneous calculation, the mechanical development and the acoustic measurements. In this study an engine weight reduction of about 30 kg with comparable noise emission compared to the production engine with cast iron crankcase is realized.

Due to their inherent high efficiency and the ease of starting once the engine is hot, turbocharged direct injection (TDI) diesel engines have emerged as one of the contending powerplants for PNGV hybrid vehicles. The interest in applying diesel engines in hybrid vehicles has prompted the modeling of direct injection diesel engine fuel consumption. The empirical equation developed in this study, which models engine friction and indicated efficiency as functions of engine operating speed and load, shows excellent agreement with test data gathered from public sources. The engine speed dependence of the friction and indicated efficiency are determined by fitting available data. Several assumed load dependences are considered. (If public data were available on engine cylinder pressure by crank angle as a function of engine speed and load, the load dependence could be determined empirically.)

A complete finite element model of the BioSID side impact dummy was created using the finite element code RADIOSS. The objective of this work was to develop an accurate and stable dummy model, which can capture the dummy behavior due to a localized impact or in a full-scale side impact finite element model with reasonable CPU time. This warranted the development of a detailed dummy model which reflects the BioSID geometrically and has material characteristics similar to the physical dummy. This paper describes the stages of the model development and discusses the issues which influence the accuracy of the dummy model predictions. It also shows comparisons of the dummy model responses and kinematics with a series of sled test data and calibration tests specified in the BioSID User's Manual.

The combustion of diesel fuels injected into a bomb at 25 bar and 520°C has been modelled and studied experimentally using laser diagnostics. A CFD model of diesel spray injection was combined with a database of results from a detailed chemical kinetic model. All fuels showed the presence of small aromatics throughout combustion (i.e. the fuel aromatics were not completely broken down). The model gave good agreement on spray penetrations and soot volume fractions around the edges of the spray. Far from the spray, the model over-predicted the amount of soot due to the absence of an OH oxidation mechanism in the CFD code. This demonstrates the need to progress to the use of a reduced chemistry scheme.

Conformability Analysis is a structured technique which seeks to identify potential problems in the manufacture and assembly of the parts and expresses the outcome as a cost of quality for the design. The analysis provides process capability estimates based on key features of parts. Considerations of the severity of possible failure of each part enables this process risk to be mapped onto a cost model to assess the expected cost of failure. Given the very high proportion of product cost determined very early in a project, and the typically significant quality costs incurred, such an approach to design evaluation is important in the product introduction process. Applications illustrate how the method is used to evaluate, compare or generate designs and show how awareness of process capability is raised in the team and in discussions with suppliers.

This paper provides an exposition of the basic and some refined inertial critical speed estimation formulas. A literature review of existing inertial formulas for estimating critical cornering speed were identified for the ultimate purpose of developing a useful, compact, and more accurate speed estimation formula. Background information is presented covering the general definitions and utility of critical speed formulas. First, as a point of reference, the basic critical speed formulas are derived. Included is a list of the key assumptions on which the basic formulas are based. It is shown that the basic formulas are founded on the fundamental principles of physics and engineering mechanics; namely, Newton's Second Law and centrifugal force.

This paper covers briefly the theory of tire-road friction, coefficient of friction measurement techniques, and the vagaries of tire-road friction as they relate to critical speed estimation. A literature review of tire-road friction studies was conducted to identify the primary factors effecting the tire-road coefficient of friction. Background information is presented covering general definitions and the connection between the basic critical speed formulas and the coefficient of friction. The primary components of tire-road friction, adhesion and hysteresis, are discussed along with minor effects such as tearing, wear, waves, and roll formation. Common coefficient of friction field measuring techniques are described, including the skid-to-stop test and drag sled. Influential factors such as tire characteristics, tire inflation pressure, road conditions, and dynamic factors are reviewed.