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The efforts of the ISO “Test Variability Task Force” have been aimed at improving the understanding and at reducing brake dynamometer test variability during performance testing. In addition, dynamometer test results have been compared and correlated to vehicle testing. Even though there is already a vast amount of anecdotal evidence confirming the fact that different procedures generate different friction coefficients on the same brake corner, the availability of supporting data to the industry has been elusive up to this point. To overcome this issue, this paper focuses on assessing friction levels, friction coefficient sensitivity, and repeatability under ECE, GB, ISO, JASO, and SAE laboratory friction evaluation tests.

Typical design challenges for Unmanned Aerial Vehicles (UAVs) require low aerodynamic drag and structural weight. Both of these requirements imply that these aircraft are considerably more flexible than conventional aircraft and their stability analyses are more complex since they require models unifying rigid body and elastic dynamics. This paper aims to built such a model for a generic UAV. The model is then used to address stability in terms of divergence and flutter.

A brief overview of the history and scope of the SAE Oil Labeling Assessment Program is presented. Then, the results of analyses on 893 samples of engine oil purchased in the retail market over the first three years of the program, are discussed. All samples were labeled with the API SF or SG Service Category, separately, or in combination with an API “C” category designation. Additionally, 43 engine oil samples found to be questionably labeled, were repurchased and analyzed; these results are included.

The continued availability of leaded specialty aviation gasolines remains as an item of crucial importance in the near-term future of general aviation; however, the development of new piston engines capable of operation with other transportation fuels available in large pools is considered an indispensable element in the long-range survival of the industry. This paper offers a road map that while allowing the continued utilization of the current fleet of piston aircraft, sets the stage for a transition to new piston powerplants and associated aircraft, compatible with widely available transportation fuels such as motor gasoline based aviation fuels for the lower and some medium performance aircraft, and aviation turbine fuels for the balance of medium and high performance airplanes.

Modern approaches to durability assurance in ground vehicle design are reviewed in the context of recent developments in computer-based analytical and experimental tools for use by designers and development engineers. Examples, using an automotive wheel assembly, are presented to illustrate the application of fatigue analysis in product development. Major challenges associated with the linking of various design tools into integrated networks appropriately configured for industrial problem solving are discussed along with an assessment of the potential benefits to be gained from such integration.

A review of many years of published work has shown that hydrogen embrittlement can occur under rolling contact conditions. Breakdown of lubrication and contamination with water have been cited as the probable sources of atomic hydrogen. In this paper, a unique fracture morphology is identified and the mechanism of the fracture progression from initiation to final catastrophic failure is proposed. Development of beneficial residual compressive stress near the contacting surfaces is one approach used to avoid this type of failure. Several alternative methods capable of developing a more desirable stress distribution will be discussed.

The Auto/Steel Partnership Corrosion Project Team has completed a perforation corrosion test program consisting of on-vehicle field exposures and various accelerated tests. Steel sheet products with eight combinations of metallic and organic coatings were tested, utilizing a simple crevice coupon design. On-vehicle exposures were conducted in St. John's and Detroit for up to seven years to establish a real-world performance standard. Identical test specimens were exposed to the various accelerated tests, and the results were compared to the real-world standard. This report documents the results of these tests, and compares the accelerated test results (including SAE J2334, GM9540P, Ford APGE, CCT-I, ASTM B117, South Florida Modified Volvo, and Kure Beach (25-meter) exposures) to the on-vehicle tests. The results are compared in terms of five criteria: extent of corrosion, rank order of material performance, degree of correlation, acceleration factor, and control of test environment.

The results of analyses on 300 samples of engine oil purchased in the retail market in 1990 are discussed. All samples were labeled with the API SF or SG Service Category, separately, or in combination with an API C category designation. Also, 17 oils previously found to be questionably labeled, from the 1989 set, were repurchased and analyzed. These results are included.

An outer loop guidance architecture was designed to control autonomous aerial refueling mission from the trail aircraft side. The design utilized bank, yaw rate, velocity and climb rate commands implemented using a previously developed adaptive trajectory concept. The concept was based on position error feedback that was used to control trail aircraft overshoot and tracking about the lead aircraft refueling point. To demonstrate this application, an open loop linear trail aircraft model at a given flight condition was selected. Inner loop control laws were designed using Linear Quadratic Regulator feedback controller and Balanced Deviation theory. The outer loop guidance architecture was then added to implement the application. The performance of the system was then evaluated for a selected position error, and disturbance.

The introduction of MultiAir technology [8] has had a strong impact on engine performance, fuel consumption, emissions and control. This technology, intended at first for gasoline engines and applied only on intake valves, is aiming at the reduction of engine breathing losses and, as a consequence, reduction of pollutant emissions and fuel consumption, together with an improvement of maximum intake efficiency. Further positive effects of MultiAir technology have been a significant improvement of Low End Torque, engine driveability (“fun-to-drive” index) and other operating conditions (e.g. idle control). Current development of MultiAir technology is focusing on a better management of hot EGR (Exhaust Gas Recirculation), still acting only on the intake side, although with specifically designed valve lift profiles. This application of MultiAir technology is pushing gasoline engines towards new levels of performance improvements.

A hybrid electric vehicle simulation tool (IBZ-Simulator) has been developed at the Fuel Cell Institute of the University of Applied Sciences Esslingen to study the fuel economy potential of a Fuel Cell hybrid urban bus. In this paper, the fundamental architecture of the FC urban buses was described, as well as the control strategy to manage the power flow between the different elements of the drive train. A comparison of the hybrid with the conventional type and ICE-hybrid type is performed, and important factors relating to the vehicle efficiency (accessory loads, vehicle mass, Fuel Cell system ramping rate and battery capacity) were assessed. The using of supercapacitor (or ultracapacitors) as peak power buffer has been investigated.

The timing of lubricating oil changes for passenger vehicles are based on set time or mileage intervals specified by their manufacturers. A few vehicle manufacturers use more sophisticated methods such as logging the engine speed and temperature and calculating the oil change intervals from this data. Neither technique tells the vehicle user anything about the true state of the oil. A novel form of viscosity sensor based on a vibrating piezoceramic element has been developed. Based on the output from such a device, a more accurate determination of the oil change interval can be made and abnormal conditions (such as the leakage of fuels into the lubricating oil) can be detected. This paper gives a brief description of the device itself and shows results from prototype samples.

A new form of SAE Transactions has been developed which allows for considerable flexibility in format, content, and distribution. A key volume includes abstracts of all SAE papers and a comprehensive depth index. Optional additions include printed and bound sets of all Transactions papers in full, subscriptions for all SAE papers, subscriptions for all SAE Transactions papers, and microfiche versions of each of these. No longer limited by physical size, all worthy papers can now be included in Transactions together with discussion, thereby enlarging the scope of Transactions approximately seven times.

This study applies the methodology developed for two earlier evaluations of diesel particulate controls to urban buses. Since these vehicles are used almost exclusively in urban areas where population is most dense, the analysis indicates the net benefits of control are very high.

The purpose of this paper is to survey the adverse environmental impacts resulting from motor vehicles, to review technologies developed to address these problems, and to summarize the current status of pollution control programs around the world.

Rapidly industrializing developing countries are now starting to note similar air pollution problems to those of the industrialized world. This paper surveys the adverse environmental impacts resulting from motor vehicles, reviews technologies developed to address these problems, and summarizes the current status of pollution controls around the world. Special focus is on the design of strategies to address the emerging problems of developing countries.

This paper deals with a conceptual aircraft cargo loader “that can do everything” commonly referred to as The Super Loader. The Super Loader is intended for use at air terminals to transport loads such as palletized cargo, containers, wheeled vehicles, shelters, and airdrop platforms from the storage docks to the military and civil aircraft, and vice versa. The loader may be described as a self-propelled, air transportable (in a C-141, C-17, C-5) 60,000 lb lifting capacity, adjustable height vehicle that will load/off load all transport aircraft from a C-130 whose cargo deck is only 3 feet, 3 inches high to a B-747 whose main deck upper limit is about 18 feet high. The Super Loader must also service the lower lobes of wide-bodies and main decks of narrow-bodied aircraft like the DC-8 and B-707. In brief, this loader will be required to interface with both civil and military cargo systems, present and future.

Of the many research approaches investigated over the years to measure the lubrication properties of aviation turbine fuels, the Ball-on-Cylinder Lubricity Evaluator (BOCLE) has emerged as the most significant test. BOCLE was originally a lubricant research device modified for low viscosity jet fuel when the Air Force encountered fuel control problems in 1965 with JP-4. It proved to be capable of detecting the presence of additives such as corrosion inhibitors which improve boundary lubrication properties and also the absence of natural lubricity agents in highly refined jet fuel. The Coordinating Research Council carried out several programs to investigate test variables such as cylinder type, humidity control and load. A semi-automated version using Falex test rings has now been commercialized and is being used to test fuels from aircraft experiencing abnormal pump wear and fuel control hang-up.

The original design-performance evaluation method of tracks and tracklaying vehicles, proposed by this writer during the WW II, was further developed and enhanced with new experience gained by many researchers. The method is based on the approximation of track action by a number of appropriate wheel actions. It is mathematically simple, and practically unique encompassing detailed track and road wheel geometry, wheel spacing, loads and load distribution together with regular soil strength parameters. It conforms methodologically with evaluation of pneumatic tires and rigid wheels, previously published in a series of SAE papers. The said papers and the present one form a concise engineering outline of Terramechanics for off-road locomotion.

The aerodynamics of the STOL aircraft can experience significant changes in proximity to the ground. A review of the existing data base and methodologies has been made and the results of that review are presented in this paper. The existing data show that in ground proximity the STOL aircraft will generally experience a reduction in the lift component regardless of the lifting configuration. Those configurations with integrated power and lift systems will have an additional effect of ground induced aerodynamic changes. This paper will discuss the existing data base and the deficiencies of that data base.