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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.

The scope of this ARP, "Startle Effect" and Crew Performance, includes pilots of turbine powered transport category aircraft and may also pertain to general aviation, the military, and/or other sectors of aircraft operations. It is focused on flight crews certified by the United States, however, may also pertain to crews certified by other countries. The scope describes all phases of training (initial, recurrent, upgrade, remedial, and operational) in both domestic and international flight operations, with the intent of assisting flight crews in responding to "startle effect".

This SAE Standard specifies a message set, and its data frames and data elements specifically for use by applications intended to utilize the 5.9 GHz Dedicated Short Range Communications for Wireless Access in Vehicular Environments (DSRC/WAVE, referenced in this document simply as “DSRC”), communications systems. Although the scope of this Standard is focused on DSRC, this message set, and its data frames and data elements have been designed, to the extent possible, to also be of potential use for applications that may be deployed in conjunction with other wireless communications technologies. This Standard therefore specifies the definitive message structure and provides sufficient background information to allow readers to properly interpret the message definitions from the point of view of an application developer implementing the messages according to the DSRC Standards.

A 10 KWe dual-mode space power system concept has been identified which is based on INEL's Small Externally-fueled Heat Pipe Thermionic Reactor (SEHPTR) concept. This power system will enhance user capabilities by providing reliable electric power and by providing two propulsion systems; electric power for an arc-jet electric propulsion system and direct thrust by heating hydrogen propellant inside the reactor. The low thrust electric thrusters allow efficient station keeping and long-term maneuvering. The direct thrust capability can provide tens of pounds of thrust at a specific impulse of around 730 seconds for maneuvers that must be performed more rapidly. The direct thrust allows the nuclear power system to move a payload from Low Earth Orbit (LEO) to Geosynchronous Earth Orbit (GEO) in less than one month using approximately half the propellant of a cryogenic chemical stage.

Panic braking can cause an “in-position” unbelted occupant to become “out-of-position.” Although the braking event dynamics and initial positioning of the occupant affect the final position at time of impact (if any), general trends are assumed. FMVSS208 now includes “out-of-position” (OOP) performance for Anthropomorphic Test Devices (ATDs) sizes twelve month to six year-old. Airbag suppression technologies currently address that range of OOP occupants. The objective of this study is to develop an approach to defining OOP test positions for the recently released 10 year old ATD and to assist restraint engineers in developing strategies to help reduce the risk of inflation induced injury to the larger out-of-position child. A series of panic brake tests was conducted with the 10 year-old Hybrid III to study panic braking kinematics. Antilock braking (ABS) generated the desired constant deceleration from high initial speeds (40 to 60mph) in three types of vehicles.

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.

This SAE Aerospace Information Report (AIR) describes procedures for use in the field to determine if 115/200 Volt, 400 Hz aircraft external electrical power connectors are excessively worn, which may result in the inability of the external power plug to be retained, intermittent electrical performance and arcing.

A vehicle model is an important factor in the development of vehicle control systems. Various vehicle models having different complexities, assumptions, and limitations have been developed and applied to many different vehicle control systems. A 14 DOF vehicle model that includes a roll center as well as non-linear effects due to vehicle roll and pitch angles and unsprung mass inertias, is developed. From this model, the limitations and validity of lower order models which employ different assumptions for simplification of dynamic equations are investigated by analyzing their effect on vehicle roll response through simulation. The possible limitation of the 14 DOF model compared to an actual vehicle is also discussed.

An air cushion restraint system has been available to the public on certain model passenger cars since January 1974. In response to this opportunity to obtain field experience, the National Highway Traffic Safety Administration has established a nationwide reporting network and investigative capability for accidents involving air-bag equipped cars. The reporting criteria for accidents require that the car be towed as a result of the accident, or that a front-seat occupant was injured, or that bag deployment occurred. The principal objective is to obtain the injury-reducing effectiveness of this restraint system in the total accident environment. This environment encompasses “towaway” accidents resulting in bag deployment and non-deployment. Definitive results are expected at the conclusion of the study. This paper summarizes the experience during the first year of the program, during which time the rate of accident occurrence was far less than originally expected.

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 Cardinal is a Super Short Takeoff and Landing (SSTOL) aircraft, which is designed to fulfill the desire for center-city to center-city travel by utilizing river “barges” for short takeoffs and landings to avoid construction of new runways or heliports. In addition, the Cardinal will fulfill the needs of the U.S. Navy for a Carrier On-board Delivery (COD) aircraft to replace the C-2 Greyhound. Design requirements for the Cardinal included a takeoff ground roll of 300 ft, a landing ground roll of 400 ft, cruise at 350 knots with a range of up to 1500 nm with reserves, payload of 24 passengers and baggage for a commercial version or a military version with a 10,000 lb payload, capable of carrying two GE F110 engines for the F-14D, and a spot factor requirement of 60 feet by 29 feet.

Error in suspension asymmetry or tire parameters may lead to vehicle drifting laterally from its intended straight-line path, which is called vehicle pull. Driver then needs to apply constant steering correction to maintain the vehicle in straight line which will lead to high driver fatigue and deteriorate driving experience. Manufacturing a perfectly symmetric suspension system is impractical, however an insight into the manufacturing tolerances of suspension system at the early design stage can be extremely useful. Also tire force and moment parameters at straight line operation and its maximum allowable variations will help in defining the tire parameter specifications and tolerances. The objective of this study was to develop a 1D model of suspension and tire system which can predict the torque experienced in steering and drift of the vehicle from straight line due to the tire force and moment and asymmetric suspension geometry.

Handling performance of a vehicle is a key characteristic determining the response of vehicle under different operating scenarios. An insight into these vehicle-handling characteristics at early stage can be extremely useful in the design and development process. Tire characterization and tuning is important and mandatory to scrutinize each functional and individual parameter of tire. Tire force and moment data is having a significant effect in vehicle handling. Segregation of tire parameter, which is contributing vehicle-handling performance, helps to identify and perform optimization for improvisation. The main objective of this study is development and integration optimized 1D tire model into multibody dynamics model of the vehicle to observe various vehicle compliances towards its handling performance target.

Two vehicle level test methods were developed that illustrate the relationship between 1st order noise in a cabin, and driveline imbalance contributors. At the launch of a new 2005 4WD sport utility vehicle program, a significant boom noise complaint was observed on many vehicles between 55-70 mph. The full time, electronic actively controlled, torque biasing transfercase was intensely reviewed as a potential source of excessive torque induced imbalance. Testing of the transfercase was performed on imbalance measurement stands, dynamometers, and in the vehicle. The result was the identification of two issues. First was that two internal to the transfercase parts were found to have excessive runout. Second was that there was a lack of vehicle correlation to transfercase imbalance. An extensive effort involving over 50 vehicles of the same model was pursued to find the source of the problem.

Recently, society has demanded better performance from motorcycle regarding comfort, fuel economy, exhaust emission, and safety, in addition to traditional performance indicators. In the development of power trains, therefore, compact and lightweight hardware with improved transmission efficiency has been introduced, along with system technologies that optimize the engine revolution speed range and reduction ratio to suit driving conditions. This approach focuses on improving overall efficiency and addressing the issues of easier drivability and greater active safety. Electronic Controlled Continuously Variable Transmission (ECCVT) with high transmission efficiency is characterized by a Dry Hybrid Belt, in addition to an electronic controlled DC motor-driven shift mechanism, and an Electronic Controlled wet multi-plates Clutch (ECC).

Although in-cylinder optical diagnostics have provided significant understanding of conventional diesel combustion, most alternative combustion strategies have not yet been explored to the same extent. In an effort to build the knowledge base for alternative low-temperature combustion strategies, this paper presents a comparison of three alternative low-temperature combustion strategies to two high-temperature conventional diesel combustion conditions. The baseline conditions, representative of conventional high-temperature diesel combustion, have either a short or a long ignition delay. The other three conditions are representative of some alternative combustion strategies, employing significant charge-gas dilution along with either early or late fuel injection, or a combination of both (double-injection).

This document describes the 2-D computer-aided design (CAD) template for the HPM-1 H-point machine or HPD available from SAE. The elements of the HPD include the curve shapes, datum points and lines, and calibration references. The intended purpose for this information is to provide a master CAD reference for design and benchmarking. The content and format of the data files that are available are also described.

This document describes the 2-D computer-aided design (CAD) template for the HPM-1 H-point machine or HPD available from SAE. The elements of the HPD include the curve shapes, datum points and lines, and calibration references. The intended purpose for this information is to provide a master CAD reference for design and benchmarking. The content and format of the data files that are available are also described.

Cross-sectional distributions of the liquid phase temperatures in fuel sprays were measured using a laser-induced fluorescence technique. The liquid fuel (n-hexadecane or squalane) was doped with pyrene(C16H10). The fluorescence intensity ratios of the pyrene monomer and excimer emissions has temperature dependence, and were used to determine the liquid phase temperatures in the fuel sprays. The measurements were performed on two kinds of sprays. One was performed on pre-heated fuel sprays injected into surrounding gas at atmospheric conditions. The other was performed on fuel sprays exposed to hot gas flow. The spray was excited by laser radiation at 266nm, and the resulting fluorescence was imaged by an intensified CCD camera. The cross-sectional distribution of the liquid phase temperature was estimated from the fluorescence image by the temperature dependence of the intensity ratio.