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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).

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.

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.

There is a definite trend toward the increasing use of “Glass Encapsulation Technology” in the automotive industry. In this technology a glass object such as a window is placed within a mould and an elastomer is injected around the window giving a tight sealing system. A wide variety of materials are currently used as the sealing materials in either static or semi-static encapsulated glazing systems, including a wide range of “elastomers”. New thermoplastic elastomer compounds are being developed that are characterized by their consistent properties; including high melt-fluidity, very good surface appearance, sealing properties, and resistance to weathering. Compound performance is highly dependent on formulation variables as well as the chemistries of the base materials. KRATON® SEBS polymers1 are block copolymers of styrene and ethylene/butylene.

(Paint) film as an alternative to spray applied paint has received growing attention in recent years. The potential for economic and environmental advantage and quality enhancement with this technology has been reported in several technical papers (Ref. 1, 3 and 4). The actual practice of film finishing, however, has received only limited notice. Film finishes have been applied to aluminum, stainless steel, PVC, and ABS. Starting in 1982, part applications include: wheel covers, door edge guards, window surrounds, roof drip moldings, lower windshield moldings, rocker panels, body side moldings, B pillars, and A pillars. Industry awareness and acceptance of film finishing as a viable alternative to spray applied paint is increasing. The two technologies are similar in many ways, yet distinctly different in other ways. They share a common goal: To yield a durable finish, economically and with superior visual impact. This paper reviews the unique aspects of film finishing.

In this paper, we present a design and control methodology of an innovated structure of switching synchronous motor. This control strategy is based on the pulse width modulation technique imposing currents sum of a continuous value and a value having a shape varying in phase opposition with respect to the variation of the inductances. This control technology can greatly reduce vibration of the entire system due to the strong fluctuation of the torque developed by the engine, generally characterizing switching synchronous motors. A systemic design and modelling program is developed. This program is validated following the implementation and the simulation of the control model in the simulation environment Matlab-Simulink. Simulation results are with good scientific level and encourage subsequently the industrialization of the global system.

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.

This paper introduces research work on 1-D model of Roots type supercharger with helical gears using 1-D simulation tool. Today, passenger car engine design follows approach of downsizing and the reduction of number of engine cylinders. Superchargers alone or their combination with turbochargers can fulfill low-end demands on engine torque for such engines. Moreover, low temperature combustion of lean mixture at low engine loads becomes popular (HCCI, PCCI) requiring high boost pressure of EGR/fresh air mixture at low exhaust gas temperature, which poses too high demands on turbocharger efficiency. The main objective of this paper is to describe Roots charger features and to amend Roots charger design.

The Twin Otter was designed as a utility bushplane for operation in the Canadian north. While it has fulfilled that role, it has also been widely adopted for use in urban commuter services which do not demand its STOL and rough field capabilities. Now, after 10 years, these commuter services are widening in scope to the point where these virtues, hitherto unused, are becoming significant. The Twin Otter, by its continued presence over this decade, has helped mould the STOL services promised for the next.

The increased use of recycled resins can create a dilemma for automotive designers. On the one hand, there is a growing initiative to increase recycled materials content on vehicles, globally. On the other hand, traditional methods of recycling polymeric materials -both thermoplastics and thermosets - can lead to degradation of engineering, mechanical, processing, and / or aesthetic properties of the resin. In an era where quality rules, this situation forces designers to accept a much lower percentage of recyclate than they might otherwise wish to use or risk unacceptable property loss in molded parts - something no automaker can “afford ” for long. Hence, a valuable feedstream of materials (polymers) often ends up destined for a landfill once many consumer products are broken down and more easily reusable or recyclable materials are salvaged. As a case in point, each passenger car built globally contains an average of 15 - 20 kg of nylon polymers.

Aerospace structures manufacturers find themselves frequently engaged in large-scale 3D metrology operations, conducting precision measurements over a volume expressed in meters or tens of meters. Such measurements are often done by metrologists or other measurement experts and may be done in a somewhat ad-hoc fashion, i.e., executed in the most appropriate method according to the lights of the individual conducting the measurement. This approach is certainly flexible but there are arguments for invoking a more rigorous process. Production processes, in particular, demand an automated process for all such “routine” measurements. Automated metrology offers a number of advantages including enabling data configuration management, de-skilling of operation, real time input data error checking, enforcement of standards, consistent process execution and automated data archiving. It also reduces training, setup time, data manipulation and analysis time and improves reporting.

Carbon fiber-reinforced plastic (CFRP) is one of the most commonly used materials in the aerospace industry today. CFRP in pre-impregnated form is an anisotropic material whose properties can be controlled to a high level by the designer. Sometimes, these properties make the material hard to predict with regards to how the geometry affects manufacturing aspects. This paper describes eleven design rules originating from different guidelines that describe geometrical design choices and deals with manufacturability problems that are connected to them, why they are connected and how they can be minimized or avoided. Examples of design choices dealt with in the rules include double curvature shapes, assembly of uncured CFRP components and access for non-destructive testing (NDT). To verify the technical content and ensure practicability, the rules were developed by, inter alia, studying literature and performing case studies at SAAB Aerostructures.

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.

The demand for improved fuel economy in both cars and trucks has emphasized the need for lighter weight components. The application of high strength steel to wheels, both rim and disc, represents a significant opportunity for the automotive industry. This paper discusses the Ranger HSLA wheel program that achieved a 9.7 lbs. per vehicle weight savings relative to a plain carbon steel wheel of the same design. It describes the Ranger wheel specifications, the material selection, the metallurgical considerations of applying HSLA to wheels, and HSLA arc and flash butt welding. The Ranger wheel design and the development of the manufacturing process is discussed, including design modifications to accommodate the lighter gage. The results demonstrate that wheels can be successfully manufactured from low sulfur 60XK HSLA steel in a conventional high volume process (stamped disc and rolled rim) to meet all wheel performance requirements and achieve a significant weight reduction.

The Ford Ranger will be a domestically built, small pickup truck engineered to many design objectives typical of a fullsize pickup, yet with four cylinder engine fuel efficiency. Ranger is a full-function on-and-off road pickup truck with a uniquely smooth ride and a capacity to carry up to a 725.7 kg. (1600 lb.) payload. The truck features a three passenger body-on-frame cab and a double wall pickup box with provision for 1.2m × 2.4m (4 ft. × 8 ft.) sheets of construction material. Featured in this comprehensive paper are the engineering highlights and innovations contributing to the accomplishment of these Small Truck objectives.

This paper presents a summary of body structural analysis applied to the 1989 Suzuki Sidekick/Geo Tracker at various stages of development and design. The structure analysis techniques were applied previously to rigidity, vibration, strength, crashworthiness and optimization. The studies confirm that the CAE technique for body structure analysis is more beneficial if it is utilized in the earlier structure development stages particularly for vibration and crashworthiness. Through the extensive use of the structural analysis technique in conjunction with the experiment, the design concept of the Sidekick/Tracker body has been optimized to a most extent.

The Clean Air Act Amendments of 1990 have brought about wholesale changes in the mandated requirements for the EPA and states to bring clean air to the country. Of particular interest to the light and heavy duty truck and bus industry are the requirements for VOC reductions in Title I, the hazardous pollutant reductions requirements in Title III, and the new permitting scheme required under Title V of the Act. The inter-relationship of lower VOC coatings, hazardous pollutant reduction, and permitting requirements will be presented. Since the Act does not fully mesh these requirements, the pathways that coating suppliers and coating application facilities can use to come into compliance will be explored. Specific VOC content of conforming coatings will be presented, how they will impact application processes, and how hazardous air pollutant reductions can be achieved is explored.

Motor thermal management of electric vehicles (EVs) is becoming more significant due to its close relations to vehicle aerodynamic performance and power consumption, while computer aided engineering (CAE) plays an important role in its development. A 1D-3D coupled model is established to characterize transient thermal performance of the motor in an electric vehicle on a high performance computer (HPC) platform. The 1D motor thermal management model is integrated with the 1D powertrain model, and a 3D thermal model is established for the motor, while online data exchange is realized between the 1D and 3D models. The 1D model gives boundaries such as inlet coolant temperature, mass flowrate and motor heat generation to the 3D model, while the 3D model gives back boundaries such as heat transfer to coolant simultaneously. Transient simulations are performed for the 140kph(20°C) driving cycle, and the model is calibrated with experimental data.

Thermal management in electric vehicles (EVs) has attracted more attention due to its increasing significance, and computer aided engineering (CAE) plays an important role in its development. A 1D-3D online coupling approach is proposed to completely characterize transient thermal performance of an electric vehicle on a high performance computer (HPC) platform. The 1D thermal management model, consisting of air conditioning, motor cooling and battery cooling systems, is integrated with the 1D control strategy model and powertrain model consisting of motor, battery, driver and vehicle models. The 3D model is established for the air flow around the full vehicle and through its underhood. The 3D model gives boundaries such as heat exchanger air flowrates and heat flows on some component surfaces to the 1D model, while 1D gives back boundaries such as heat exchanger heat loads, component surface temperatures and fan speed simultaneously.

A theoretical model is presented for predicting springback of wide sheet metal subjected to 2D-stretch-bending operation. The material is assumed to be normal anisotropic with n-th power hardening law, σ = Fεn. Two types of stretch-bending experiment, bending with simultaneous stretching and stretch-bending followed by consecutive re-stretching, is conducted using AK sheet steel and sheet aluminum alloy A5182-O. The measured values of springback are in good agreement with analytical ones for a wide range of bending radii, stretching forces, and loading conditions. Furthermore, a calculation method for predicting springback configurations of 2D sheet metal parts with arbitrary cross-sections which include both stretch-bending and stretch-bending-unbending deformation is proposed.