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Currently, advancements in Rapid Prototyping (RP) technologies have led to considerable amount of research activities and has been playing a major role in the area of tooling development for which Rapid Tooling (RT) term was coined. While rapid prototyping techniques are employed to make prototype tools, the basic idea of the rapid tooling is to produce prototype and zero series parts by using prototype tools so the parts truly represent the future production. This paper will present an evaluation of a RP and RT technique in developing tools (punch and dies) for sheet metal forming, which had been manufactured and tested. Both punch and die have been manufactured by combining Stereolithography (SL), RP technique, with nickel electroforming process. The stereolithography technique that had been utilized in developing models for the tools had been built with modeling pattern called Accurate Clear Epoxy Solid (ACES).

Currently, advancements in Rapid Prototyping (RP) technologies have led to considerable amount of research activities and has been playing a major role in the area of tooling development for which Rapid Tooling (RT) term was coined. Rapid prototyping techniques are employed to make prototype tools. While, the basic idea of the rapid tooling is to produce prototype and zero series parts by using prototype tools so the parts truly represent the future production. This paper will present an evaluation of a RP & RT technique in developing tools (punch and dies) for sheet metal forming, which had been manufactured and tested. Both punch and die have been manufactured directly from Stereolithography (SL). The stereolithography technique that had been utilized in developing models for the tools had been built with modeling pattern called QuickCast infiltrated with Aluminum-Filled Epoxy, designated as Quick Tool.

It has been recently shown that (Ce, Zr)O2 mixed oxides provide improved catalytic performances compared to pure CeO2. Cerium oxide is the active Oxygen Storage Capacity (OSC) component in three way catalysts. However, higher performances, including OSC enhancement, can be achieved with thermally stable solid solutions of Ce and Zr oxides. In the present paper, we describe the structure and the advantages of Ce rich (Ce, Zr)O2 solid solutions and the improved catalytic properties of these materials when used in association with platinum. Various analytical techniques were used including thermo-reduction methods, OSC measurements, surface area measurements, XRD, HRTEM, XPS, and XANES/EXAFS.

Sensitivity analysis is a usual method to evaluate how “sensitive” is a product performance to changes in its design variables. This type of analysis identifies the critical variables related to product performance and other aspects that may have less demanding manufacturing controls. This paper presents a case study in the automotive market, applying the 1-D dynamic modeling as an auxiliary tool to the sensitivity analysis. The objective of this procedure is to reduce physical prototypes tests. This evaluation, if taken during preliminary design of the system, could give competitive advantages, with a reduction in product development cycle time and cost.

Two types of One-Way Clutch (OWC) are commonly used in automotive applications – the roller and the sprag types. Some manufacturers claim the advantages of a different type of OWC having a mechanical diode OWC. The aim of this research is to study the mechanical diode system in order to point out reasons that explain why this configuration is not a spread out system in automotive applications that require lockup functionality. To achieve this objective the research work focuses on the development of 1-D models to simulate system behavior and evaluate product performance against design variables. Improvements to the system are suggested based on the simulation results.

It is well known that backpressure is one of the important parameters to be minimised during the exhaust system development. Unfortunately, during the first phases of an engineering process of a new engine, engine prototypes are not available yet. Due to this the exhaust system backpressure is generally evaluated using simulation software, and/or measuring the backpressure by a flow rig test at room temperature. Goal of this paper is to compare exhaust backpressure results obtained respectively: i) at the room temperature flow rig; ii) at the engine dyno bench; iii) by simulation with one of the most common 1D fluidodynamics simulation tool (Gt-Power). A correlation of the three different techniques is presented.

Diesel engines, especially CR (Common Rail) DI (Direct Injection) TCI (Turbo Charged Inter-cooled), share a wide acceptance in the passenger car market due to the enormous torque and flexibility at low engine speed. A pre - condition for the use of a diesel engine in a motorcycle is that the disadvantages like combustion noise and visible smoke are reduced or eliminated. Moreover the fuel economy and performance characteristics of a diesel engine are dedicated to be used in a touring or large displacement motorcycle. The AVL engine concept is the first high performance diesel engine to be specially designed for motorcycles in terms of packaging and styling. To compensate for the limited engine speed range a gearbox with a wide ratio spread is required. This leads to a manual transmission with at least 6 gears or an automatic transmission. For the AVL concept an AMT (Automated Manual Transmission) was selected.

Late developments in tires and in lightweight, high horsepower engines and transmissions have enabled the earthmoving and mining industry equipment manufacturers to design and produce several types of preproduction 100-ton capacity trucks. A straight-forward approach to the design of a 110-ton end dump truck on two axles with a hydro-mechanical drive was followed by KW-Dart Truck Co. to produce a low cost per ton-mile vehicle.

Inverters are solid state devices which change DC to 120VAC electricity. They are sufficiently rugged and reliable to make them practical for use on utility vehicles for operating thumpers, tools, lights and induction motor loads. The SCR type rather than the transistor type inverter is generally required for inductive and reactive loads. Static inverters operate from battery input. They provide power without running an engine, but are limited by battery capacity so work best in intermittent load applications. Dynamic inverters operate from alternator input and will handle continuous loads to 7200 watts with truck engine running.

This paper shows some aspects of the automotive voltage energy system level shift from 14 to 42 Volts. New features and prospective emissions/fuel economy requirements are creating electrical power needs in future automobiles, which today's conventional system cannot adequately supply at 14 Vdc (nominal, with a 12 Volt battery). It will be necessary to provide electric motors, DC/DC converters, inverters, battery management, and other electronic controls to meet higher voltage requirements. Suppliers must now include 42 Volt components and systems within their product range and make these new components as light, small, and cost efficient as possible. This paper is a compilation of several published works aiming to offer a synthesis to introduce this subject to the Brazilian Automotive Market.

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.

Because of the size and weight of the various components going into the machine, new approaches were used to solve the practical limitations of manufacturing facilities, shipping clearances, and erection procedures. Although the general appearance of the machine is similar to previous units, there are a number of new design features incorporated in the unit. This paper will be limited to the major design considerations as follows: adaption to stripping two seams of coal simultaneously; dipper with two doors; computerized hydraulic steering maintaining Ackerman correction; double end drive crawlers and belt tensioning; and electrical innovations.

This paper describes the concept, design, and options of a new power shift transmission family for industrial equipment in the 50-100 hp range. The converter, clutch, and gearing arrangements provide the basis for various transmission configurations with both a drop and straight through output. The designs allow multiple usage of components within a transmission and between different sizes of transmissions. The various gearing, bearing, and clutch designs are based on proved experience factors, and as such will provide a new reliable family of transmissions.

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.

A first attempt to study civil aircraft operations comprehensively, prior to having the airplane, occurred before the initial operation of U.S. subsonic jets. One airline carried out a manual-simulated “paper jet” operation lasting fifteen months. Today, computerized simulation of machines, methods, and operations has become commonplace, and replaces the slide rule and tedious day-by-day inputs of aircraft operational criteria. Computerized simulations are also applied to every aspect of the SST design and operations. These are important, but the results being should be used with caution and judgement.

A review of the Pure Oil Performance Trials conducted at Daytona International Speedway are presented. Background information pertaining to conducting of tests, design of the equipment, and instrumentation required for the various events are discussed. The performance trials have evolved into three basic tests -- Economy, Acceleration, and Braking. The objective of the Performance Trials is to provide data that motorists can utilize in evaluating new cars and selecting new models.

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.