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Test Method for Catalytic Carbon Brake Disk Oxidation

The scope of the test method is to provide stakeholders including fluid manufacturers, brake manufacturers, aircraft constructors, aircraft operators and airworthiness authorities with a relative assessment of the effect of deicing chemicals on carbon oxidation. This test is designed to assess the relative effects of runway deicing chemicals by measuring mass change of contaminated and bare carbon samples tested under the same conditions.

Missionized Wear Testing

Publicize Aircraft Recommended Practice for Missionized Wear Testing on Wright Patterson’s Landing Gear Test Facility’s 168i dynamometer.

Landing Gear Based Weight and Balance Systems

This document outlines historical systems which have used the landing gear as a sensor or installation point for full aircraft weight and balance systems. A number of systems have been developed, installed, certified, and placed in service but few systems remain in regular use. The document will capture the history of these systems, reasons (where known) for their withdrawal from service, and lessons learned.

Wheels - Radial Impact Test Procedure - Road Vehicles

The SAE recommended practice provides a uniform laboratory test procedure for evaluating radial(road hazard) impact collision resistance of all wheels intended for use on passenger vehicles and light trucks.
Technical Paper

New Materials and Experiences for the Industrialization of Pu Structural Rim Technology

Processes involving use of reactive polymers received recently considerable attention also for producing components suitable for automotive structural applications. In particular polyurethane structural RIM technology seems to be the route of choice in terms of productivity, reliability and physico- mechanical performances in order to fit the automotive industry needs in the production of parts requiring superior load bearing properties. In this frame the development of long pot life snap-cure resins, fast and effective reinforcement preforming techniques as well as the development of computerized provisional processing methodologies are of paramount importance in view of industrialization of the technology. In this paper a description of the work carried out by Enichem Montedipe and Montedison is given. In particular a new family of PU systems, based on special isocyanate variants, is reported.
Technical Paper

Critical Compression Loads on Aluminum Honeycomb Panels

The purely theoretical evaluation of critical compression loads seems complex and not very reliable in the case of honeycomb panels, on account of the numerous parameters in play and their complex interrelationships. This report provides the designer with a fast tool for preliminary calculations, consisting of a finite-element mathematical model with elastic-linear code (which can be processed using a PC), which makes it possible to obtain information very closely resembling the real situation.
Technical Paper

A Driving Simulator Using Microprocessors

An inexpensive driving simulation system with sufficient fidelity has been developed. The system produces motion cues of four degrees of freedom, visual and auditory cues, and control feel on the steering wheel. This paper describes the features of this newly developed system and gives examples that demonstrate its effectiveness. The motion cues provided in this system are yaw, heave, and lateral and fore/aft accelerations. The lateral and fore/aft accelerations are simulated by tilting the simulator compartment. A computer-processed road image is given through a CRT monitor. The restoring torque of the steering wheel is produced by an electrical servosystem via a coil spring. Cruising sound is given in order to improve speed perception. Since the system uses digital computers, the vehicle characteristics are altered easily by merely rewriting the software. This enables us to simulate special vehicle dynamics such as front & rear wheel steering.
Technical Paper

A Study on the Performance of Guideway Bus Steering Control System

In this paper a computer simulation study on the effects of steering parameters on lateral dynamics of the guideway bus to contribute to a development practice of designing optimum steering control system are dealt with. A stability limit of vehicle lateral motion is analyzed and an emphasis is laid on the effects of moment of inertia of a conventional steering wheel and lateral elasticity of the guide rail which have proven to reduce the critical vehicle speed. It is pointed out conclusively that a normal bus equipped with additional simple guidance equipments can be guided smoothly on a simple guideway at adequately high vehicle speed.
Technical Paper

Integration of Reliability, Maintainability and Quality Parameters in Design

Synthesizing different customer and functional requirements into an acceptable design configuration within a given space constraints is a challenging task for design engineers. The principles for designing efficiency, noise levels, maneuverability, safety, durability, etc. into the product are well understood. However, designing for reliability, maintainability and quality turns out to be a long-drawn laborious process due to unavailability of simplified design procedures. The author in this paper develops the understanding of reliability, maintainability and quality design principles and methods for products, with specific reference to vehicle designs.
Technical Paper

Silicone Thermal Interface Materials for Under-Hood Electronics

Heat dissipation is one of the key issues facing automotive engineers, as performance, reliability and longevity of electronic devices have all been shown to be directly affected by temperature. The current thermal challenges are unprecedented, as smaller engine compartments and higher component density raise under-hood temperatures, while electronic devices with greater functionality and power also generate more heat than previous designs. The unique properties of silicone thermal interface materials can help achieve higher levels of physical and electrical performance in automotive electronics -- facilitating heat dissipation in a variety of forms, including adhesives, gels, encapsulants, gap fillers, fabricated pads and phase change materials.
Technical Paper

Improvement of Dynamic Characteristics of Electromechanical Commutating Devices

Modern production is intensified by the extensive application of computing art to structure design. This paper deals with the results of numerical simulation of electromechanical commutating devices. Speed of operation, vibrostability, reliability and durability are basic characteristics, which can be satisfied by studying mathematical models of mechanical and magnetic systems. During the impact interaction of elastic links several modes of vibrations are excited. By developing certain conditions, the amplitudes of the higher modes can be increased by changing the intensity of energy dissipation and responsiveness of the mechanical system. Such parameters as the position and configuration of the contact elements, ratio of their natural frequencies and others should guarantee the smallest amplitudes of rebounds with a possibility to minimize transient processes occurring in the building ofthe operation.
Technical Paper

Fuel Quality Control by Mid Infrared Spectroscopy

Gasolines and diesel fuels of wide source were analyzed with the aim to predict the quality through the mid infrared spectroscopy and the algorithms PCA-PCR and PLS. The results revealed that octane number, cetane number, MTBE, benzene, aromatics and specific gravity could be predicted with good reliability. The other relevant fuel physical-chemical characteristics were beyond the precision of the standard test methods.
Technical Paper

Mathematical Models of Fastened Structural Connections

The development of efficient and reliable methods for the design and analysis of fastened structural connections is among the most important problems in aerospace applications because fastened structural connections are common sites of failure initiation. Numerical simulation of fastened structural connections is difficult because there are complicated interactions between the fasteners and the structural components being joined and one of the most important attributes of a fastened connection, the clearance, is a stochastic variable. This paper presents a mathematical model for frictionless shear connections and its implementation within the framework of the p-version of the finite element method.
Technical Paper

Analysis of Vehicle Response Data Measured During Severe Maneuvers

During the past few years, the National Highway Traffic Safety Administration's (NHTSA) Vehicle Research and Test Center has generated a plethora of reliable vehicle test data during their efforts to study vehicle rollover propensity. This paper provides further analyses of a small selection of some of the data. The analyses provided here derive in part from the previous work, trying to answer some of the questions spawned by earlier analyses. The purpose of this paper is to introduce several new concepts to the study of vehicle roll stability and provide case studies using the results available from the NHTSA testing. Results from several severe maneuvers are studied in detail to gain understanding of vehicle response in these cases.
Technical Paper

Fundamental Physics Behind New Suspension Concept for Automobiles

The Transverse Leaf suspension with Superior Roll Axis is a new suspension concept for automobiles. It enables the load transfer during a turn to be more evenly redistributed between the two wheels on the same axle thus optimizing its tires lateral force capabilities. The TLSRA concept is made up of a single transverse leaf spring linking the middle of the sprung mass to the outer end of 2 transverse suspension arms per axle. Those transverse arms are mounted close to the middle of the sprung mass with their attachment points located above the mass centroïd. Each wheel assembly is mounted directly onto the free end of its respective suspension arm. Because body roll is now counteracting vertical load transfer during transient and permanent operating conditions, this suspension enables designers to keep spring stiffness low without compromising road handling.
Technical Paper

An Automatic Vehicle Controller for Stability and Handling Tests

An automatic vehicle controller (AVC) which was specified, designed, fabricated, installed and used on a variety of vehicles, including automobiles, light trucks, and sport utility vehicles is described. The AVC controls the vehicle's steering, and input waveforms of virtually any type or complexity can be specified from computer files containing steering wheel angle commands as functions of time. Also, algorithms which use motion sensor feedback in the steering control logic can be programmed. Throttle and brake controls can also be provided.
Technical Paper

Elimination of Roll, Squat, and Dive Through Biased Suspension Response

Conventionally sprung vehicles are subject to rolling and pitching of the sprung load as the vehicle corners and accelerates, respectively. Designs which incorporate active elements seek to control these movements, frequently resulting in compromised performance or reduced fuel economy. This paper considers the possible replacement of conventional springs, shocks, and anti-sway bars with specified fluid spring components. The fluid spring components offer biased response to dynamic load variations in the following manner: provide support of the sprung load equal to the magnitude of the load at each moment, and either compressing readily to absorb upward forces originating in the wheel assembly which exceed the magnitude of the load at that moment, or extending rapidly to provide support equal to the magnitude of the load at that moment, in the event the wheel assembly tracks through a hole.
Technical Paper

Dynamics Simulation Research on Rigid-Elastic Coupling System of Car Suspension

In modern car, to reduce car deadweight, lightweight technology is widely used; and to improve comfortable and handling performance, many rubber bushings installed between car body and suspension. These parts have difference characteristics during car running at high speed comparing these at static state. Accounting the suspension performance has a decisive influence on a car, the flexible parts should be taken into account in the suspension/steering system simulation model. As a deviant phenomenon, the steering wheel shimmy affects the suspension's dynamic characteristics greatly. To analysis this abnormal running state, the front wheel bounce tracks were figured out by using different front suspension model. The flexible parts installed in suspension are idealized respectively as rigid poles, flexible beams or forces, hence, the rigid suspension analytical model and the rigid-elastic suspension model analytical were built respectively.
Technical Paper

NEWPED - A Stealth Auxiliary Engine in a Bicycle with Very Low Noise, Low Pollutant Emission and Good Fuel Economy

The development history of a 30cc 2-stroke engine power unit in the covered rear wheel for retrofit into standard bicycle chassis. The rear wheel acts as cooling fan for the air cooled long stroke engine with catalyst exhaust system, autochoke carburetor, autolube oil pump, electric start and inertia start, single speed automatic transmission and 7 speed hub final drive. The space in the rear wheel contains intake air filter, exhaust system, fuel tank, oil tank and engine with drive train, the complete engine being only 94mm wide. The complete covered power unit is nearly undetectable as the rear wheel covers resemble road racing bicycles. There is very low stationary and pass-by noise (64 db[A]), no exhaust gas opacity or smell, very low vibration level and very good fuel economy up to 133 km/l.
Technical Paper

Applying Design of Experiments, Accelerated Testing and Weibull Analysis Methods to Improve ABS ECU Reliability

This paper presents, in a case study format, a methodology for combining the methods of Design of Experiments, Accelerated Testing, and Weibull Analysis to improve the reliability of an ABS Electronics Control Unit (ECU). While much literature focuses on each method individually, sometimes it's necessary combine all of these methods to achieve product improvement. The paper walks through the steps of using an multi-environment over-stress accelerated test routine, with DOE methods to evaluate key factors, and then applying Weibull and Weibayes methods to validate the new proposal and estimate expect life improvement.