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Technical Paper

175°C-Capable Thermoplastic Elastomers for Automotive Air Management and Sealing Applications

2007-11-28
2007-01-2576
Flexibility, oil resistance, and the need for heat resistance to 150°C-plus temperatures have traditionally limited automotive design engineers to two options - thermoset rubber or heat-shielding conventional thermoplastic elastomers (TPE). Both of these options present limitations in part design, the ability to consolidate the number of components in a part of assembly, and on total cost. This paper presents a class of high-performance, flexible thermoplastic elastomers based on dynamically vulcanized polyacrylate (ACM) elastomer dispersed in a continuous matrix of polyamide (PA) thermoplastic. These materials are capable of sustained heat resistance to 150°C and short-term heat resistance to 175°C, without requiring heat shielding. Recent advancements in blow molding and functional testing of the PA//ACM TPEs for automotive air management (ducts) and underhood sealing applications will be shown.
Technical Paper

4 Stroke Gasoline Engine Performance Optimization Using Statistical Techniques

2001-12-01
2001-01-1800
The engine designer has to find novel methods to optimize the engine efficiency faster as the engine development cycle is getting shortened due to the continuous growing market demands. Engine optimization involves fine tuning of the various engine parameters and conducting a large number of tests on actual engine test bed. In this paper, modern techniques that have been used to optimize a small 4stroke air-cooled engine performance have been described. The engine has been modelled using one-dimensional thermodynamic engine modelling software (AVL-BOOST). Design of experiments (DoE) tools have been used to optimize the engine variables. The input parameters form an orthogonal array of L27 matrix and the out put characteristics of the engine (responses) have been predicted by using BOOST software. This design matrix has been used to study and optimize thirteen factors in three levels (313).
Technical Paper

A 3-D Joint Model for Automotive Structures

1992-06-01
921088
A simple, design-oriented model of joints in vehicles structures is developed. This model accounts for the flexibility, the offsets of rotation centers of joint branches from geometric center, and the coupling between rotations of a joint branch in different planes. A family of joint models with different levels of complexity is also defined. A probabilistic system identification is used to estimate the joint model parameters by using the measured displacements. Statistical tools which identify important parameters are also presented. The identification methodology is applied to the estimation of parameters of a B-pillar to rocker joint.
Technical Paper

A 360×226 Pixel CMOS Imager Chip Optimized for Automotive Vision Applications

2001-03-05
2001-01-0317
Multiple automotive systems are now being developed which require an imager or vision chip to provide information regarding vehicle surroundings, vehicle performance, and vehicle passenger compartment status. Applications include lane departure, lane tracking, collision avoidance, as well as occupant position, impaired driver, and occupant identification. These applications share many requirements, including robust design, tolerance for the automotive environment, built in self-test, wide dynamic range, and low cost. In addition, each application has unique requirements for resolution, sensitivity, imager aspect ratio, and output format. In many cases, output will go directly to vehicle systems for processing, without ever being displayed to the driver. Commercial imager chips do not address this wide spectrum of requirements. A CMOS imager chip has been designed to address these unique automotive requirements.
Technical Paper

A CFD Multidimensional Approach to Hydraulic Components Design

2007-10-30
2007-01-4196
This paper presents a multidimensional approach to the hydraulic components design by means of an open-source fluid dynamics code. A preliminary study of a basic geometry was carried out by simulating the efflux of an incompressible fluid through circular pipes. Both laminar and turbulent conditions were analyzed and the influence of the grid resolution and modeling settings were investigated. A qualitative description of the internal flow-field distribution, and a quantitative comparison of pressure and velocity profiles along the pipe axis were used to asses the multidimensional open-source code capabilities. Moreover the results were compared with the experimental measurements available in literature and with the theoretical trends which can be found in well-known literature fundamentals (Hagen-Poiseuille theory and Nikuradse interpolation). Further comparison was performed by using a commercial CFD code.
Technical Paper

A Case for RFID in Indian Automotive Industry

2005-10-23
2005-26-301
Radio Frequency Identification (RFID) technology holds great potential for reshaping business strategies. The use of RFID to capitalize on data flow in supply chain could be one of the most significant developments. This paper presents the case for RFID implementation in automotive supply chain. It also gives brief description about RFID technology and its deployment in Ashok Leyland. Steps involved in implementing this technology are also briefed in this paper.
Technical Paper

A Case for Standardization

1974-02-01
741143
This paper outlines several specifications for heavy-duty truck wiring, especially wire and harness assemblies, and low-tension electrical wire. Emphasized are avoidance of substandard wiring and components, identification of circuits, grounding techniques, and construction. It is noted that improved specifications will result in reduced maintenance costs.
Technical Paper

A Comparison of Near-Field Acoustical Holography Methods Applied to Noise Source Identification

2019-06-05
2019-01-1533
Near-Field Acoustical Holography (NAH) is an inverse process in which sound pressure measurements made in the near-field of an unknown sound source are used to reconstruct the sound field so that source distributions can be clearly identified. NAH was originally based on performing spatial transforms of arrays of measured pressures and then processing the data in the wavenumber domain, a procedure that entailed the use of very large microphone arrays to avoid spatial truncation effects. Over the last twenty years, a number of different NAH methods have been proposed that can reduce or avoid spatial truncation issues: for example, Statistically Optimized Near-Field Acoustical Holography (SONAH), various Equivalent Source Methods (ESM), etc.
Technical Paper

A Comparison of Seven Different Noise Identification Techniques

2003-05-05
2003-01-1690
Today's NVH engineers have at their fingertips a myriad of different noise source identification techniques available with which to locate noises. Unfortunately, with so many different techniques available, it is not always clear which technique is the best for a specific application. Should one use Sound Intensity? Or is Acoustic Holography a better tool? But if there are noises above 5kHz, which technique works then? And what is Beamforming? Would that work? With so many choices, it is required to know before the test which technique is the best choice. This paper will give an overview of 7 popular techniques to help the practicing NVH engineer decide which technique is the best for a specific application. A practical explanation along with a real life example will be given to help make clear where and how a technique can be used.
Technical Paper

A Complete Engine Diagnostic System for Military Application

1989-02-01
890397
The possibility of fast identification of defective components and the reduction of repair time of vehicles is a common requirement for military applications. In the development of a new power-pack for a tank application IVECO has included a complete diagnostic system that provides the following performances: at first level (i.e. on the field) the system provides indications on simple repair operations or the indication of a seriuos power-pack fault, such to require power-pack replacement. This level is fully supported on the tank itself and requires no external support. at second level (i.e. In a field workshop) the system identifies the defective sub-components, replaceable in such workshop, or indicates the need of a higher level workshop. This level requires an off-board, portable diagnostic unit.
Technical Paper

A Composite Linear and Nonlinear Approach to Full-Vehicle Simulator Control

2005-04-11
2005-01-0937
This paper presents an approach to full-vehicle simulator control which accounts for nonlinearities in a vehicle/simulator system. The control scheme presented is based on the estimation of the system inverse dynamics. A composite linear/nonlinear approach to inverse system identification (SYS-ID) is presented. The linear portion of the SYS-ID uses time-domain methods to estimate the impulse response of the inverse system in a least squares sense. These results are then extended by using the regularized approach to least squares estimation. The nonlinear part uses the support vector machine to approximate the nonlinear deviations from the linear model. Two approaches to using this composite model are presented. Examples of the linear SYS-ID techniques are shown for a 2×2 system.
Technical Paper

A Contract-Based Installation Methodology for Safety-Related Automotive Systems

2013-04-08
2013-01-0192
Today's automobiles contain a lot of electrical and electronic (E/E) systems with safety-related functionality. In a design-process compliant to the industrial standard ISO 26262 unknown dependencies between events and elements are risks that potentially violate safety requirements or safety goals. Therefore, the identification and analysis of dependent failures is important. Physical environment influences like temperature are one class of factors which can lead to coupling effects and cause dependent failures. In this paper we show a novel contract-based approach to deal with geometric installations of elements in an automobile. It avoids violations of safety requirements by identification and prevention of dependent failures resulting from coupling effects between elements. The influences of an element on environment factors and the failure effects of such environment factors on elements are explicitly specified as physical conditions.
Technical Paper

A Control and Fault Diagnosis Method for Pressure Sensor Based Brake Control System

2005-04-11
2005-01-1576
This paper proposes a control and fault diagnosis method for a pressure sensor based brake control system. The proposed wheel brake pressure control method consists of feedforward and feedback controller, respectively. The main purpose of the feedforward controller is to set the operating point of the feedback control, and the purpose of feedback controller is to improve the control response and the steady state error characteristic. Also, the proposed fault diagnosis method consists of three processes: a fault detection process, a fault isolation process and a fault identification process. In the fault detection process, a fault is detected by the difference between the estimated signal and the measured signal. Then, in the fault isolation process, the location of the fault is determined. Finally, in the identification process, the size and effect of the fault are evaluated.
Technical Paper

A Cooperative Airline Program to Evaluate Engine Parts Aging Effects on a Current Turbofan Engine Model

1970-02-01
700329
The contribution that aged hardware makes to performance deterioration is of interest to operators of JT3D turbofan powered aircraft since a significant percentage of these engines have exceeded 20,000 hr of operation. Recent studies involving numerous engine disassemblies, rebuild, and test cell runs reveal the most significant effects of aged hardware are the loss in high and/or low compressor stall margin; and, that a large number of parts must be replaced to realize a significant improvement in fuel consumption, with the exception of the reduction that can be obtained by controlling turbine seal clearances.
Journal Article

A Copula-Based Approach for Model Bias Characterization

2014-04-01
2014-01-0735
Available methodologies for model bias identification are mainly regression-based approaches, such as Gaussian process, Bayesian inference-based models and so on. Accuracy and efficiency of these methodologies may degrade for characterizing the model bias when more system inputs are considered in the prediction model due to the curse of dimensionality for regression-based approaches. This paper proposes a copula-based approach for model bias identification without suffering the curse of dimensionality. The main idea is to build general statistical relationships between the model bias and the model prediction including all system inputs using copulas so that possible model bias distributions can be effectively identified at any new design configurations of the system. Two engineering case studies whose dimensionalities range from medium to high will be employed to demonstrate the effectiveness of the copula-based approach.
Technical Paper

A Database for Crash Avoidance Research

1987-02-23
870345
A database derived from information obtained in state police accident reports has been developed to support problem identification and counter-measure development in crash avoidance research. This database is sufficient in size to permit analyses of the relationship between specific vehicle design characteristics and crash involvement. Preliminary analyses of this database suggest that is is comparable with the nation's crash experience.
Technical Paper

A Detailed Synchronous Machine Model

2002-10-29
2002-01-3205
A synchronous machine model is set forth that simultaneously incorporates magnetizing path saturation, leakage saturation, and transfer function representations of the rotor circuits. A parameter identification procedure consisting of voltage step tests as well as standstill frequency response tests is described. The model's predictions are validated using the Naval Combat Survivability Generation and Propulsion test bed.
Technical Paper

A Diagnostic Technique for the identification of Misfiring Cylinder(s)

1987-02-01
870546
This paper introduces a diagnostic technique for the detection of misfiring cylinders in internal combustion engines. The technique requires the analysis of the instantaneous angular velocity of an engine flywheel. The results show that the mean cyclic acceleration, maximum variation in angular velocity, and the cyclic period of acceleration can be used as a measure for the mean net torque and the mean net expansion pressure torque produced by each cylinder. The proposed technique has proven to be effective in identifying a faulty cylinder using efficient and simple computations.
Technical Paper

A Discussion on Fault Detection, Isolation, Identification and Reconfiguration in Networked Control Systems of Aerospace Vehicles

2011-10-04
2011-36-0088
In this work, the problem of fault detection, isolation, and reconfiguration (FDIR) for Networked-Control Systems (NCS) of aerospace vehicles is discussed. The concept of fault-tolerance is introduced from a generic structure, and a review on quantitative and qualitative methods (state estimation, parameter estimation, parity space, statistic testing, neural networks, etc.) for FDIR is then performed. Afterwards, the use of networks as loop-closing elements is introduced, followed by a discussion on advantages (flexibility, energy demand, etc.) and challenges (networks effects on performance, closed-loop fault-effects on safety, etc.) represented thereby. Finally, examples of applications on aerospace vehicles illustrate the importance of the discussion herein exposed.
Technical Paper

A Flexible Approach to Environmental Compliance Through the Aircraft Maintenance and Repair Manuals

1998-11-09
983121
In the aircraft industry's continual effort to select materials that meet the varied environmental regulations, Boeing has taken on the challenge of addressing the regulations and at the same time providing the airlines with functional alternatives. A mission was undertaken to provide the airlines with a flexible means to comply with their individual local environmental regulations, especially as they relate to solvent applications. This has been accomplished through the use of the aircraft maintenance and repair manuals, allowing each individual airline to link each specific solvent cleaning process to a “solvent series identification” that represents a solvent of their choosing from a list.
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