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This paper investigates the yaw dynamic behaviour of a seven axle tractor semitrailer combination vehicle developed by VRDE (Vehicle Research & Development). The semitrailer has four steerable axles which follow command steering law i.e. all axles of semitrailer are steered in a particular relation with articulation of tractor. A 4 dof (degree of freedom) linear yaw plane model was developed for this combination vehicle. Yaw response characteristics such as lateral acceleration, yaw rate and articulation angle for step and sine steer is obtained from this model. Effects of speed on the above parameters are also studied to the same steering inputs. Lateral tyre forces due to semitrailer steering at various speeds are estimated to understand its distribution on each axle. Steady state yaw rate and articulation angle gain are obtained to predict the understeer / oversteer behaviour of combination vehicle.

MBB and Rockwell, under DARPA/NAVAIR and GMOD contract, are currently designing an experimental aircraft which will be dedicated to demonstrate “enhanced fighter maneuverability” (EFM) and supermaneuverability in particular. The aircraft is designed to break one of the last barriers left in aviation, the stall barrier. It will be able to perform tactical maneuvers up to 70° angle of attack and thus achieve very small radii of turn. Such highly instantaneous 3-dimensional maneuvers are of significant tactical value in future air combat with all aspect weapons. Key to the penetration into this unexplored flight regime is thrust vectoring in pitch and yaw. This feature is also used to enhance agility in critical flight conditions and to enhance the decoupling of fuselage aiming and flight path control as required for head-on gun firing.

Residual stress and hardness in steel due to thermal, mechanical, and fatigue deformations are determined by an X-ray diffraction method. The sharp temperature rise associated with electrical discharge machining causes austenitizing, rehardening, and tempering, and results in high tensile residual stress. Shot-peening quality is evaluated from residual stress and hardness induced by the peening. Rolling contact fatigue of carburized and hardened bearings causes a transformation of austenite to martensite, and thereby generates more residual compression, and also causes permanent fatigue softening. Less softening is observed in inner races of consutrode and cross-forged steels than in air-melted steel, and the former steels exhibit greater fatigue life at early and mean failure levels.

Agile aircraft (X-29, X-31, F-18 High Alpha Research Vehicle, & F-16 Multi-Axis Thrust Vector) test pilots, while flying at high angles of attack, experience difficulty predicting their flight path trajectory. To compensate for the loss of this critical element of situational awareness, the X-31 International Test Organization (ITO) installed and evaluated a helmet mounted display (HMD) system into an X-31 aircraft and simulator. Also investigated for incorporation within the HMD system and flight evaluation was another candidate technology for improving situational awareness - three dimensional (3D) audio. This was the first flight test evaluating the coupling of visual and audio cueing for aircrew aiding. The focus of the endeavor, which implemented two visual and audio formats, was to examine the extent visual and audio orientation cueing enhanced situational awareness and improved pilot performance during tactical flying.

This SAE Aerospace Standard (AS) covers 6-point and 12-point flare nut crowfoot, flare nut wrenches, double end flare nut wrenches, combination box end and flare nut wrenches, combination open end and flare nut wrenches, and ratcheting flare nut wrenches that are designed with the following requirements: (a) non-distorting usage; (b) possessing the strength, clearances, and internal wrenching design to be used on hydraulic tube fittings that conform to the requirements of SAE J514 and ISO 8434-2; and (c) transmitting torque to tube fittings without bearing on the apex of fitting wrenching points. Inclusion of dimensional data in this document is not intended to imply that all of the products described herein are stock production sizes. Consumers are requested to consult with manufacturers concerning lists of stock production sizes.

This standard covers the design, performance, and test requirements for high strength, thin wall, commercial sockets, universal sockets, and box wrenches used for the attachment and detachment of metric spline drive, high strength, and high temperature aircraft fasteners. Inclusion of dimensional data in this standard is not intended to imply that all of the products described herein are stock production sizes. Consumers are requested to consult with manufacturers concerning lists of stock production sizes. This standard is based on, but not limited to, the following external spline wrenching system:

This SAE Aerospace Standard (AS) covers high strength thin wall (commercial) sockets, universal sockets, box wrenches and torque adaptors which possess the strength, clearances, and internal wrenching design so configured that, when mated with 12-point fasteners conforming to the requirement of AS870, they shall transmit torque to the fastener without bearing on the outer 5% of the fastener's wrenching points. Inclusion of dimensional data in this document is not intended to imply that all of the products described herein are stock production sizes. Consumers are requested to consult with manufacturers concerning lists of stock production sizes. The dimensional limits of box and combination wrench lengths have been established to provide configuration control for tool storage applications.

This SAE Metric Aerospace Standard (MA) provides dimensional, performance, testing and other requirements for high strength, thin wall, double head box and combination wrenches which possess an internal wrenching design so configured that, when mated with hexagon (6 point) fasteners, they shall transmit torque to the fastener without bearing on the apex of the fastener’s wrenching points. This standard provides additional requirements beyond ANSI B107.9 appropriate for aerospace use. Inclusion of dimensional data in this document is not intended to imply all of the products described therein are stock production sizes. Consumers are requested to consult with manufacturers concerning lists of stock production sizes.

The Convair/Navy XFY-1 VTOL fighter was ahead of its time. In the early 1950s it became the first airplane to take off vertically, hover, transition to high speed level flight, transition back to hover, and land vertically. Pilot “Skeets” Coleman made a number of successful flights at Moffett Field South of San Francisco, at Brown Field near the California/Mexican border, and at San Diego's Lindbergh Field. This “first of a kind” aircraft soon adopted the name “POGO”. The POGO with its stall proof delta wing had near perfect aerodynamic characteristics in hover, transition and level flight. There were no “black boxes” needed for stability augmentation. The POGO was one of the very first aircraft to use hydraulic power flight controls - a system used today on all modern fighter and transport aircraft.

Externally applied unbalanced forces and their corresponding impulses are generally excluded from consideration in regards to the evaluation of the collision phase events for a system comprised of two motor vehicles undergoing collinear impact. This exclusion is generally warranted secondary to the fact that the collision force and its corresponding impulse are dominant during the collision phase. Conceptually, two exclusions exist to this approach. The first is the situation in which significant physical restraints are present to the displacement of one or both collision partners and are of sufficient magnitude as to require inclusion. Generally, this represents the exceptional case and includes, but is not limited to, situations in which one vehicle is snagged, in a non-eccentric manner, by a rigid narrow-width object such as a pole or other similar restraint, prior to the occurrence of the subsequent vehicle-to-vehicle collision under evaluation.

Over the past years many have been predicting various dramatic changes in the vehicle including automatic route guidance, the office in the vehicle, and the auto PC. There are a number of factors which need to come together before significant momentum can develop toward realizing any of these predictions. This paper enumerates these factors and explores the current state and possible evolution of each. While each of these factors could stall progress, the linchpin is likely to be wireless communication. The current state of wireless and its capabilities going forward are examined in depth.

Optimizing the wiper system performance motivates the design engineer to create a product as robust as possible against the occurrence of wipe defects related to vibratory phenomena between the rubber blade and the windshield. In some configurations, these vibrations generate visual or audible annoyance for the driver. These instabilities phenomena only appear under specific operating and environmental conditions characterized by windshield moisture and cleanness, contact pressure of the rubber blade on the glass, attack angle of the wiper blade on the windshield, component stiffness, windshield curvature etc. In the process of eliminating all potential instabilities, modeling the wiper system structures can contribute to understand its working dynamics. Therefore, a new computation tool is developed and validated by experimentation on a specific test bench.

Acoustic comfort inside the vehicle is required whenever a wiper system is in function: front wiper motor noise is of great influence on the global comfort and its perception inside the car is 100% due to transmission of vibrations through wiper system fixation points on the vehicle. As any active source, both car manufacturer and system supplier need to be involved, at early stages of project development, in order to master the vibroacoustic integration of the system into the vehicle. This paper presents an experimental methodology dedicated to the front wiper system that offers the possibility to estimate the acoustic comfort inside the vehicle during project deployment phase, when modifications can still be proposed. Based on the XP-R-19701 standard, the procedure allows to measure, on a bench, the dynamic forces transmitted via the fixation points and details how to transpose them to the vehicle, taking into account the different specificities of the wiper system.

In this paper are presented some results about the dynamic of the wiper systems, vibratory phenomena and some influences of the friction, the weight and the clearances.