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Technical Paper

"Nickel electroformed" tools development through stereolithography (SLA) for sheet metal forming~An evaluation study

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).
Technical Paper

"Quattro"-Drive for Every Day Driving

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.
Technical Paper

"Quick" tools development through stereolithography (SLA) for sheet metal forming~An evaluation study

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.
Technical Paper

<PP/SEBS> Compounds: Sealing an Easier Future for Automotive Designers and Specifiers

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.
Technical Paper

(Ce, Zr)O2 Solid Solutions for Three-Way Catalysts

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.
Technical Paper

(Paint) Film Finishing in Practice

(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.
Technical Paper

(Test Developed For) Classifying Valve Bridge Cracking Solutions in Cylinder Heads

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.
Journal Article

0W-16 Fuel Economy Gasoline Engine Oil Compatible with Low Speed Pre-Ignition Performance

It has been long established fact that fuel economy is a key driving force of low viscosity gasoline engine oil research and development considered by the original equipment manufacturers (OEMs) and lubricant companies. The development of low viscosity gasoline engine oils should not only focus on fuel economy improvement, but also on the low speed pre-ignition (LSPI) prevention property. In previous LSPI prevention literatures, the necessity of applying Ca/Mg-based detergents system in the engine oil formulations was proposed. In this paper, we adopted a specific Group III base oil containing Ca-salicylate detergent, borated dispersant, Mo-DTC in the formulation and investigated the various effects of Mg-salicylate and Mg-sulfonate on the performance of engine oil. It was found that Mg-sulfonate showed a significant detrimental impact on silicone rubber compatibility while the influence from Mg-salicylate remains acceptable.
Technical Paper


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.
Journal Article

1-D Simulation Study of Divided Exhaust Period for a Highly Downsized Turbocharged SI Engine - Scavenge Valve Optimization

Fuel efficiency and torque performance are two major challenges for highly downsized turbocharged engines. However, the inherent characteristics of the turbocharged SI engine such as negative PMEP, knock sensitivity and poor transient performance significantly limit its maximum potential. Conventional ways of improving the problems above normally concentrate solely on the engine side or turbocharger side leaving the exhaust manifold in between ignored. This paper investigates this neglected area by highlighting a novel means of gas exchange process. Divided Exhaust Period (DEP) is an alternative way of accomplishing the gas exchange process in turbocharged engines. The DEP concept engine features two exhaust valves but with separated function. The blow-down valve acts like a traditional turbocharged exhaust valve to evacuate the first portion of the exhaust gas to the turbine.
Journal Article

1-g Suit Port Concept Evaluator 2008 Test Results

The Lunar Electric Rover (LER), which was formerly called the Small Pressurized Rover (SPR), is currently being carried as an integral part of the lunar surface architectures that are under consideration in the Constellation Program. One element of the LER is the suit port, which is the means by which crew members perform Extravehicular Activities (EVAs). Two suit port deliverables were produced in fiscal year 2008: a 1-g suit port concept evaluator for functional integrated testing with the LER 1-g concept vehicle and a functional and pressurizable Engineering Unit (EU). This paper focuses on the 1-g suit port concept evaluator test results from the Desert Research and Technology Studies (D-RATS) October 2008 testing at Black Point Lava Flow (BPLF), Arizona. The 1-g suit port concept evaluator was integrated with the 1-g LER cabin and chassis concepts.
Technical Paper

10 Years of STOL - The Twin Otter's First Decade

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.
Technical Paper

100 HP / 200 Nm Diesel Motorcycle with 6 Speed Automated Manual Transmission

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.
Technical Paper

100% Post-Consumer Recycled Nylon 6: Repolymerized Resin Provides Full Mechanical, Physical, & Aesthetic Properties

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.
Technical Paper

100,000 HP Gas Turbine Load Test Facility

The problem of testing large gas turbines at full load in the factory has been solved with the construction of a load test facility utilizing a gas turbine compressor as the load absorption device. Design philosophy and features are reviewed, and a summary, of operating experience to date is presented.
Technical Paper

100-kWe Lunar/Mars Surface Power Utilizing the SP-100 Reactor with Dynamic Conversion

An integration study was performed coupling an SP-100 reactor with either a Brayton or Stirling power conversion subsystem. A power level of 100 kWe was selected for the study. The power system was to be compatible with both the lunar and Mars surface environment and require no site preparation. In addition, the reactor was to have integral shielding and be completely self-contained, including its own auxiliary power for start-up. Initial reliability studies were performed to determine power conversion redundancy and engine module size. Previous studies were used to select the power conversion optimum operating conditions (ratio of hot-side temperature to cold-side temperature). Results of the study indicated that either the Brayton or Stirling power conversion subsystems could be integrated with the SP-100 reactor for either a lunar or Mars surface power application.
Technical Paper

1000 kW Sodium-Sulfur Battery Pilot Plant: Its Operation Experience at Tatsumi Test Facility

Since 1978, the Agency of Industrial Science and Technology (AIST) of MITI has promoted research and development of “Large-Scale Energy Conservation Technology” popularly known as the “Moonlight Project”. As the first step, “system technology tests” using improved lead acid batteries started at Kansai Electric's Tatsumi Electric Energy Storage System Test Plant on October 1, 1986. The results showed that this system can work not only as a load-leveling apparatus but also as a high-quality power source which can support the utility power system with its load frequency control and voltage regulation capabilities. As the second step of these R&D activities, a 1MW/8MWh sodium-sulfur battery pilot plant was constructed at the same Tatsumi site. On July 11, 1991, 1000 kW× 8H facility, the largest of its type in the world, was completed and started operation. This paper describes the construction experience and operation results of the pilot plant.
Technical Paper

10PC20 Swash Plate Type Variable Displacement Compressor for Automotive Air Conditioners

Up to now, various compressor models for automotive air conditioners have been manufactured to answer the needs of car manufacturers for fuel economy and quietness. The 10PC20 compressor, developed for automotive air conditioners, is the world's first swash plate type compressor having a continuously variable displacement mechanism. The 10PC20 is aimed at realizing a large displacement compressor with a continuously variable displacement mechanism, which has not been achieved until today. To achieve this goal, the 10PC20 design is based on the swash plate type compressor, consisting of double-headed pistons, which is adaptable to a large displacement and has excellent rotating balance and durability. The 10PC20 changes its displacement continuously by changing the inclination of the swash plate (swash plate angle) continuously. (See photo. 1 and 2) The 10PC20 adopts two variable displacement principles.
Journal Article

11 Reasons to Use Automated Metrology

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.
Technical Paper

11 Rules of Design for Manufacturing when Producing Pre-Impregnated Carbon Fiber-Reinforced Plastic Components - an Application at SAAB Aerostructures

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.