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Synthesis of a new type of FEPM (tetrafluoroethylene-propylene alternating copolymer), its curing behavior and physical properties were studied. Recently, the concern of heat, motor oil and chemical resistance of the elastomer material has been growing and the performance of FEPM, which has excellent chemical and oil resistance against organic and inorganic acids and bases, especially amines even at elevated temperatures, has drawn considerable attention. However, there were some requirements for FEPM to improve its physical properties. In order to resolve the problem, some studies have been made, but the results of the studies were insufficient. Especially, its compression set is over 30%. In this work, modification of FEPM copolymer was studied to improve the cure stability and physical property as well as mold release, and a new type of FEPM was developed. This new FEPM has a specific cure site which can be introduced quantitatively into the tetrafluoroethylene-propylene backbone.

The reduction of particulate emissions from diesel engines is one of the most challenging problems associated with the exhaust air pollution control. Particulate emissions can be controlled by the adjustments of the combustion parameters of a diesel engine but these measures result in increased emissions of oxides of Nitrogen.Diesel particulate Filters (DPF) hold out the prospects of substantially reducing regulated particulate emissions but the question of the reliable regeneration of filters still remains a difficult hurdle. Many of the solutions proposed to date suffer from high engineering complexity, cost, thermal cracking, increased backpressure which in turn deteriorates diesel engine combustion performance. This paper presents an improved computer aided analytical approach for controlling Diesel soot particulate emission by Cyclone separator. Reduction of soot particles in the exhaust in turn reduces the Diesel Particulate Matter formation.

The scatter of bolt clamping force tightened by the conventional torque control method very often causes loosening and fatigue failure of bolted joints. Different values of frictional coefficients between mating screw surfaces and between mating bearing surfaces cause the scatter of clamping force in each tightening. In this study, a new tightening method to reduce the scatter of clamping force of bolted joints has been developed. In the new method, the frictional coefficients at screw and at bearing surface of bolt head can be separately detected during a tightening process by simultaneously application of tightening torque and compressive force to a bolt. The tightening experiments have been successfully conducted to demonstrate the efficiency and usefulness of the proposed method. Furthermore the optimum configuration of bolt head to improve the accuracy of the proposed method has been investigated.

Road loads tire models are used in the automotive industry in full vehicle simulations to compute the loading from the road into the chassis encountered in proving ground durability events. Such events typically include Belgian Block events, bump events, potholes and others. Correctly capturing tire enveloping forces in such events has historically been challenging - several different approaches exist each with its own limitations. In this paper a model is presented which captures the first order tire dynamics (frequencies lower than 80 Hz) and associated enveloping loading without the need of an effective road profile. The theory behind this tire model is briefly introduced. Importantly, a comprehensive study of the validation of the tire model is given which shows correlation for full vehicle dynamic proving ground events. A Virtual Tire Lab (VTL) pre-processing tool is also presented which is used to compute tire model input parameters from a validated non-linear FEA tire model.

Since road roughness is an important source of vehicle vibration, a system model for NVH analysis requires a tire model which accurately predicts spindle response to road input. Most tire models currently used in the auto industry do not meet this requirement, because they are based on static stiffness of the tire and do not produce realistic response to input at the patch. This paper investigates a new modal tire model with patch input capability as a component within a vehicle system model. Comparisons are also presented between the behavior of the new tire model and a conventional spring model. To validate the performance of the tire model for NVH analysis, simulated vehicle responses to bump input are compared to chassis roll test results. Good correlation between the model prediction and the chassis roll measurements is observed.

The behaviour of the tyre plays an important role in controlling the horizontal motion of the vehicle. In vehicle dynamics studies, a good representation of tyre behaviour is therefore a necessity. A series of tyre measurements have been carried out on the road in stationary conditions. The data obtained have been represented by mathematical expressions on the basis of a formula. The coefficients in the formula represent some of the typifying quantities of the tyre and the formula is capable of describing all characteristics of side force, brake force and self aligning torque with great accuracy. The behaviour of the tyre during combined cornering and braking has successfully been described by a model which makes use of the obtained mathematical expressions and some tyre-modelling theory. The side force characteristic governs the behaviour in lateral direction and the brake force characteristic in longitudinal direction.

The development of a puncture sealant which effectively seals tread punctures 3/16 inch diameter and less is described; included are discussions of the material compositions and properties, the mechanism of sealing, and field testing of the product.

To overcome future stringent regulations on pollutant emissions and to decrease CO2 emissions and fuel consumption, hybrid vehicles seem to be one of the near future most promising technologies. This type of car uses complex energy management and control strategy. Simulation can be very useful for the development of such a control system. This paper highlights a new library developed under the AMESim software that enables the simulation of complex interactive systems in vehicles. In addition, the possibility to combine with other AMESim modules, allows the users to add more complexity to any of the sub-components of the vehicle. As an illustration of this new tool capability, we propose in this paper a simulation example of the Prius, the most known hybrid vehicle which was the first commercial vehicle in 1997 and selected as the 2004 Car of the Year in Europe.

Electrochemical techniques such as repassivation potential measurements and electrochemical impedance spectroscopy (EIS) have become important tools in corrosion and corrosion inhibitor research. However, these techniques reflect the response of the total surface area of the exposed sample and cannot distinguish between types of localized corrosion e.g. pitting or crevice corrosion. Current density mapping (CDM) is a technique that uses a fine stainless steel needle, vibrating at a set frequency and scans over the surface of a sample in a plane micrometers above the sample surface. By mapping the current distribution over a surface, sites of localized corrosion can be characterized and the effect of a corrosion inhibitor monitored.

Rack and Pinion steering systems are increasingly common in automobiles due to their superior performance characteristics. Because of differing vehicle parameters, even very similar vehicles must have different steering systems. Small changes in linkage dimensions, to accommodate space constraints, can result in significant changes in steering performance. Thus, each proposed design must be thoroughly analyzed and evaluated. A new, analytical engineering tool has been developed to help design engineers find optimum 2-D steering mechanisms quickly. It provides designers with the capability to input vehicle parameters, run a simple solver, and converge to an optimized steering system in seconds. Designers can also search through different possibilities quickly and find the best solutions for the constraints that are present.

There are three criteria for an ideal ship-marine machinery noise analysis tool: It is applicable over a wide frequency range, it has modeling fidelity, and it is economical and can be used for design iterations. Vibratory energy from the machinery sources to the ocean follows 3-dimensional paths. Energy is attenuated by isolations, structural discontinuities, damping treatment, before radiated to the water. Traditionally, Finite Element Method (FEM), Boundary Element Analysis (BEM), and Statistical Energy Analysis (SEA) are used for noise analysis. FEM models can be constructed to follow complex machine geometry well. However, its applicable frequency range is limited by the practical mesh size. On the other hand, SEA can be used in the middle to high frequency ranges where the system modal density is adequate. The basic building blocks of a SEA model consist of plates, shells, and beams.

Laser Doppler Vibrometry (LDV) is an established tool in automotive engineering for non-contact vibration measurements. The LDV method is not just limited to measurements on single test points but can also be used for full field scanning of entire structures, such as vehicles, braking systems, etc. Such Scanning LDVs (SLDVs) have found many applications in the automotive industry. However, for full body modal analysis, the use of SLDVs has traditionally been restricted due to the fact that only the Out-of-Plane (OOP) component of the velocity vector could previously be measured, whereas tri-axial accelerometers provide OOP and In-Plane (IP) data simultaneously. This limitation has been overcome with full 3-dimensional scanning LDVs, since 2002. A 3-D SLDV consists of three independent SLDV measurement heads, each measuring the vibration of a scan point from a different direction. The working principle and mathematics behind are discussed later in this paper.

The exterior and interior noise level of passenger cars has been reduced in the past to a large extent by legislation and on the demand of the car purchasers. One important marketing aspect today is the possibility to enjoy driving, which is determined by the noise quality and not the noise level inside passenger cars. However the interior noise quality of today's passenger cars does not always satisfy the people affected. In the development process of a vehicle, the noise quality is determined on a subjective basis by test drivers. A great deal of experience and time is required for the subjective assessment and for the further definition of strategies and their application to meet sound engineering targets for noise quality. This paper reports on the result of a R&D program to develop a software based Noise Quality Map with which the interior noise quality of passenger cars can be determined on an objective basis by measurement in real-time.

Significant progress could not have been made in the Sound Quality area without the invention and development of engineering tools. For the sound engineer, the binaural recording head is a primary example of one of those tools. The use of the binaural recording head was crucial to the development of the sound characterization process and has become an essential tool in the Sound Quality areas in Ford Motor Company. A similar tool, The Ford Vehicle Vibration Simulator, has been developed for the vibration engineer. The vehicle vibration simulator (VVS) is unique, consisting of vibration of the vehicle seat (6 degrees of freedom), steering wheel (4 DOF), vehicle floorpan section (1 DOF), and the brake or accelerator pedal (1 DOF). Many vibration test systems have been developed to study human response to vibration, especially for military and space applications. To our knowledge, this is the first multi-axis, fully integrated vibration test system to be used for automotive applications.

Nowadays, given the shrinking budgets and deadlines of the aerospace and automotive industries, the importance and need of the requirements engineering is becoming more and more evident. This means that progressively more users face a difficult task on the different environments of project development: 1) to write better requirements; and 2) to do it faster than ever. It would be nice if they had some tools to help them and abbreviate such a difficult task. This work summarizes the development of a new tool that does exactly that. Its wizard guides the user through the steps necessary to create good requirements when writting a requirements document, depending on the kind of requirements document desired. For example: there are significant differences between user requirements and system requirements documents. The wizard script is composed by a serie of questions related to the parts of the scheme to build a complete and effective requirement.

The generalization of exhaust aftertreatment systems along with the growing awareness about climate change is leading to an increasing importance of the efficiency over other criteria during the design of reciprocating engines. Using experimental and theoretical tools to perform detailed global energy balance (GEB) of the engine is a key issue for assessing the potential of different strategies to reduce consumption. With the objective of improving the analysis of GEB, this paper describes a tool that allows calculating the detailed internal repartition of the fuel energy in DI Diesel engines. Starting from the instantaneous in-cylinder pressure, the tool is able to describe the different energy paths thanks to specific submodels for all the relevant subsystems.

Transmission error is the main cause of gear noise in automobile transmissions, and recently can be estimated by numerical analysis [1]. First, in this report, we establish the accurate numerical analysis of transmission error by using FE analysis and Hertz's contact analysis of gear tooth stiffness. Secondly, on the basis of the established numerical analysis, we develop a new tooth flank form to reduce transmission error. The new tooth flank form aims to ensure the coincidence of meshing stiffness at all meshing positions. Finally, a validation test using an experimental prototype is performed, and we confirm that the estimated effect by the new tooth flank form has been obtained.

This paper proposes a new braking torque distribution strategy for electric vehicles equipped with a hybrid hydraulic braking and regenerative braking system. The braking torque distribution strategy is proposed based on the required braking torque and the regenerative braking system’s status. To get the required braking torque, a new strategy is designed based on the road conditions and driver's braking intentions. Through the estimated road surface, a robust wheel slip controller is designed to calculate the overall maximum braking torque required for the anti-lock braking system (ABS) under this road condition. Driver's braking intentions are classified as the emergency braking and the normal braking. In the case of emergency braking, the required braking torque is to be equal to the overall maximum braking torque. In the case of normal braking, the command braking torque is proportional to the pedal stroke.

The new elastohydrodynamic (EHD) code developed by FEV Motorentechnik GmbH, Aachen, is designed to improve the predictability of journal bearing designs and thereby increase the reliability of safety factors in the development of highly loaded internal combustion engines. Using this tool design targets can be achieved with higher confidence levels. The developed code may be linked to commercial multibody system (MBS) codes such as ADAMS® while simultaneously representing the important characteristics occurring in transiently loaded journal bearings including elastic deformation, cavitation, and non-constant speed. Static deviations from ideal journal and bearing shell shapes caused by manufacturing and assembly processes can be considered and are substantially important in the evaluation of journal bearings. Presented is an economic bearing model approach which includes elastic bearing deformations.