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The Electro Gyro-Cator allows a driver to monitor his progress, plot and follow courses to a destination, select alternate routes, and drive more safely on unfamiliar roads or at night. Employing a sealed helium gas-rate gyro, the Electro Gyro-Cator offers visual display (CRT display) of a car's present location, direction and route, with overlay maps for fast, simple route selection and monitoring. The primary elements of the unit include trip and direction sensors, a 16-Bit central processing unit, a CRT display screen and a collection of transparent overlay maps fitted to the screen.

An essential feature of the Audi Quattro permanent four-wheel drive system is in the inter-axle differential located on the hollow output shaft in the gearbox: the drive is taken from this differential forward to the front differential through the inside of the hollow shaft, and rearward to a propellor shaft driving the rear differential. The major advantages in everyday driving include improved traction and a reduced tendency toward throttle induced changes of attitude. The greater traction allows not only better progress in difficult road conditions; it also gives better acceleration in difficult traffic situations, such as when joining a busy main road. The more easily predictable handling response to throttle changes means that Quattro vehicles have better tracking stability. Altogether, the active safety and "roadability" are considerably improved.

The testing system developed will decrease the time and the costs involved in evaluating cylinder head valve bridge designs. The test uses actual data generated from engine testing to recreate the valve bridge cracks that occur during dynamometer and vehicle testing. This paper focuses on the system description, the test development, design modifications, and the test results obtained. Testing shows that this method correctly separates valve bridge designs by test cycle life using statistical methods. It is a cost effective and timely alternative to dynamometer testing.

This work deals with the CAE simulation of the behaviour of a belt employed in a CVT transmission of a large displacement scooter engine. Both FEM and MBS simulations were performed, in order to estimate the dynamic loads acting on the component and the stress state the belt is subject to. The MBS simulations were backed up by simple FEM tests performed in order to estimate the elastic properties of elementary portions of the belt. The MBS system comprised the belt and the two pulleys. As a result, the force components the pulleys exert on the belt were calculated. FEM non-linear analyses were performed in order to estimate the stress state the belt experiences. The belt's both manufacturing and working conditions were simulated.

Two Cummins B5.9L engines were fueled with 100% biodiesel in excess of 48 months by the Agricultural Engineering Department at the University of Missouri-Columbia. The engines used to power Dodge pickups. The engine lubricating oil was sampled at 1000 mile intervals for analysis. Statistical analysis of the engine lubricating oil indicated that the wear metal levels in the lubricating oil were normal. A reduction in power was noted when the engines were tested using a chassis dynamometer. The 1991 pickup has been driven 110,451 km and the 1992 pickup has been driven approximately 177,022 km. The pickups averaged 6.9 km/L. Engine fuel efficiency and material compatibility issues are addressed in the paper.

An efficient design of the gearbox is crucial for the expected performance of the vehicle both in terms of life and NVH. This involves design and analysis of gears, shafts, bearings, gear layout and speed ratios. Conventionally gears, shafts and bearings are designed and analysed independently. When the design of these parts change, their effect on related parts is estimated separately, leading to loss of time. Alternately, an integrated approach through simulation is adopted for the new two wheeler's gearbox by modeling on Romax designer software, consisting of shafts, bearings and gears. For the target load cycle, gear and bearing lives, shaft deflections and stresses are estimated. While the targets for stresses, deflections and lives are set logically and with experience, these are also compared with those of reference vehicle by creating and analysing reference gearbox model.

This paper summarizes the techniques and guidelines which were used to reduce the driver perceived noise level of a 145-210 HP series of agricultural tractors. Graphs of case study test results and comments on subjective noise quality are provided to guide the acoustic novice through the complexities of the vehicle sound environment in a methodical problem solving format.

Transfer path analysis is a powerful tool to support the vehicle NVH development. On the one hand it is a fast method to gain an overview of the complex interplay in the vehicle noise generation process. On the other hand it can be used to identify critical noise paths and vehicle components responsible for specific noise phenomena. FEV has developed several tools, which are adapted to the considered noise phenomena: Powertrain induced interior noise and vibration is analyzed by VINS (Vehicle Interior Noise Simulation), which allows the deduction of improvement measures fast enough for application in the accelerated vehicle development process. Further on vehicle/powertrain combinations not realized in hardware can be evaluated by virtual installation of the powertrain in the vehicle, which is especially interesting in the context of engine downsizing from four to three or six to four cylinders.

In a running engine, various impacts are excitation sources for structural vibrations and engine noises. Engine noises are classified, depending on their excitation sources, into the combustion noise, the combustion induced mechanical noise and the mechanical noise. It is difficult to measure such noises separately because some impacts occur closely in time and space. In this paper, a transient noise generation model of an engine was proposed considering vibration and its damping of engine structure. The present model was verified through the single explosion excitation experiment for a stationary engine. Using the noise generation model, the combustion noise was separated from the total noise radiating from a running four-stroke gasoline engine for motorcycles. It was found that the combustion noise had larger power at lower frequencies than higher frequencies. However, its contribution to the total engine noise was relatively small.

THIS paper deals with the road-test portion of the extensive efforts made during 1937 by the Cooperative Fuel Research Committee to get as precise a correlation as possible between the laboratory knock ratings of automobile fuels and their corresponding ratings in cars on the road. It is anticipated that the comprehensive results of car tests reported here, taken together with the results of the laboratory rating program reported in the companion paper, will serve as the basis of the continuing studies aimed at developing the best possible correlation between road and laboratory knock ratings. Work similar to that reported here has been conducted concurrently in England by the Institution of Petroleum Technologists, using British cars and fuels. An exchange of information between the British and American groups working on this problem is being made.

The cooperative road tests carried out during 1941 have added considerable information and experience to that already existing on the subject of road detonation testing. Extensive data were obtained on the fuel requirements of the 1940 and 1941 models of the three most popular cars. Corresponding data were obtained on the knocking characteristics of current gasolines representing the bulk of the sales volume in various parts of the United States. On account of large variations in octane-number requirement among different cars of the same make - due to differences in ignition timing, combustion-chamber deposit, and other causes - and on account of variations in commercial gasolines, it has been necessary to use statistical methods of analysis in the appraisal of fuel and engine relationships. These methods of analysis have been applied in a number of ways, and have proved very useful.

The size of the 1978 automotive service market is the total dollars spent on car and truck repair and maintenance in 1978. The 1978 personal-use automotive service market is the retail dollars spent in 1978 on repair and maintenance for cars and trucks used primarily for personal transportation. Service market estimates in this report do not include body repair parts and body repairs. Bureau of Economic Analysis data indicate a personal-use service market, excluding do-it-yourself (DIY) service, of $36 billion. A similar estimate made by General Motors Research Laboratories, based on a large national survey of actual consumer expenditures, is $ 37 billion. The personal-use automotive service market, excluding DIY, is roughly 3/4's the size of the total automotive service market, based on data from the Motor and Equipment Manufacturers Association and Frost & Sullivan, Inc.

A gasoline Road Octane study was conducted by the Coordinating Research Council (CRC) to evaluate the effects of heavy aromatics (C9 and heavier) and ethanol content on Road Octane performance independent of Research Octane Number (RON) and Motor Octane Number (MON). Maximum-throttle and part-throttle Road ON’s were found to be well predicted by equations containing only RON and MON terms. Heavier aromatics were found to have a small adverse effect on both maximum-throttle and part-throttle Road ON independent of its direct effects on RON and MON. The all-car data did not show a significant ethanol-content effect, but eight of the thirty-seven cars did show significant effects for ethanol content.

A student team from Minnesota State University, Mankato's Automotive Engineering Technology program entered the Clean Snowmobile Challenge 2000. A 1998 Polaris Indy Trail was converted to indirect fuel injection running on a computer controlled closed loop fuel system. Also chassis, exhaust, and hood design modifications were made. The snowmobile was designed to compete in eight events. These events included acceleration, emissions, hill climb, cold start, noise, fuel economy/range, handling/driveability, and static display. The snowmobile modifications involved every aspect of the snowmobile with special emphasis on emissions and noise. Laboratory testing led to the final design. This paper details the modifications and test results.

Without engine noise, the cabin of an electric vehicle is quiet, but on the other hand, it becomes easy to perceive refrigerant-induced noise in the automotive air-conditioning (A/C) system. When determining the A/C system at the design stage, it is crucial to verify whether refrigerant-induced noise occurs in the system or not before the real A/C systems are made. If refrigerant-induced noise almost never occurs during the design stage, it is difficult to evaluate by vehicle testing at the development stage. This paper presents a 1D modeling methodology for the assessment of refrigerant-induced noise such as self-excitation noise generated by pressure pulsation through the thermal expansion valve (TXV). The GT-SUITE commercial code was used to develop a refrigerant cycle model consisting of a compressor, condenser, evaporator, TXV and the connecting pipe network.

Two vehicle level test methods were developed that illustrate the relationship between 1st order noise in a cabin, and driveline imbalance contributors. At the launch of a new 2005 4WD sport utility vehicle program, a significant boom noise complaint was observed on many vehicles between 55-70 mph. The full time, electronic actively controlled, torque biasing transfercase was intensely reviewed as a potential source of excessive torque induced imbalance. Testing of the transfercase was performed on imbalance measurement stands, dynamometers, and in the vehicle. The result was the identification of two issues. First was that two internal to the transfercase parts were found to have excessive runout. Second was that there was a lack of vehicle correlation to transfercase imbalance. An extensive effort involving over 50 vehicles of the same model was pursued to find the source of the problem.

The demands for comfort and a cleaner environment have been increasing for the past years for motorcycle as well as car manufacturers. With the need to decrease the time-to-market, there is a clear drive to apply CAE-based methods in order to evaluate new designs and to propose design changes that solve any identified problems. More specifically, the demands on the comfort of the rider are not only related to ride & handling and vibration levels(1), but also to the noise levels generated by the motorcycle. This paper presents the virtual modeling of one-cylinder engine of a motorcycle that identifies the mechanism behind the generation of an annoying noise. Furthermore, different possible design changes were evaluated in order to solve the problem. A combined experimental and numerical approach was followed to achieve this. Experiments were used to identify important parameters that determine the engine behavior and thus are critical for the modeling of such an engine.

This paper documents a joint development process between General Motors and Dow Automotive to improve primary body structure frequencies on the GM family of midsize vans by utilizing cavity-filling structural foam. Optimum foam locations, foam quantity, and foam density within the body structure were determined by employing both math-based modeling and vehicle hardware testing techniques. Finite element analysis (FEA) simulations of the Body-In-White (BIW) and “trimmed body” were used to predict the global body structure modes and associated resonant frequencies with and without structural foam. The objective of the FEA activity was to quantify frequency improvements to the primary body structure modes of matchboxing, bending, and torsion when using structural foam. Comprehensive hardware testing on the vehicle was also executed to validate the frequency improvements observed in the FEA results.

General Motor's Corvette product engineering was given the challenge to find mass reduction opportunities on the painted body panels of the C6 Z06 through the utilization of carbon fiber reinforced composites (CFRC). The successful implementation of a carbon fiber hood on the 2004 C5 Commemorative Edition Z06 Corvette was the springboard for Corvette Team's appetite for a more extensive application of CFRC on the C6 Z06 model. Fenders were identified as the best application for the technology given their location on the front of the vehicle and the amount of mass saved. The C6 Z06 CFRC fenders provide 6kg reduction of vehicle mass as compared to the smaller RRIM fenders used on the Coupe and Convertible models.