Search Results

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.

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.

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.

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.

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.

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.

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.

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.

The EUROMIR-95 flight was selected as model for the HUBES experiment: a similar duration (135 days), a similar crew (3 men), similar schedule organisation (8 hours work, 8 hours sleep, 8 hours off-duties), similar workload for the crew and the mission control (performance of scientific experiments), similar setup for communication and data processing, and similar layout of the MIR station, as the simulation was performed in the MIR simulator located at the Institute for BioMedical Problems (IBMP) in Moscow. The Scientific Programme of HUBES had been elaborated by integration of 31 experiments from more than 80 research proposals from Principal Investigators from Europe, USA and Russia, in domains of Physiology, Psychology, Operations and Technology.

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.

The experience accumulated with a prototype 1000 HP diesel electric tractor since 1969 is described. The new 1500 HP V220 diesel electric tractors are described along with some of the initial operation of these two units. Experience with the initial 1000 HP unit and the two 1500 HP tractors confirm the necessity of additional testing and experimentation to refine the design to get greater productivity with reduced operator fatigue. The unpredictability of the load and operating surface are major problems that present a real challenge to the engineer.

Direct fuel injection is becoming mandatory in two-stroke S.I. engines, since it prevents one of the major problems of these engines, that is fuel loss from the exhaust port. Another important problem is combustion irregularity at light loads, due to excessive presence of residual gas in the charge, and can be solved by charge stratification. High-pressure liquid fuel injection is able to control the mixing process inside the cylinder for getting either stratified charge at partial loads or quasi-stoichiometric conditions, as it is required at full load. This paper shows the development of this solution for a small engine for moped and light scooter, using numeric and experimental tools. In order to obtain the best charge characteristics at every load and engine speed, different combustion chambers have been conceived and studied, examining the effects of combustion chamber geometry, together with injector position and injection timing

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.

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.

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.