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The aim of this work is to apply an innovative adaptive ℒ1 techniques to control flutter phenomena affecting highly flexible wings and to evaluate the efficiency of this control algorithm and architecture by performing the following tasks: i) adaptation and analysis of an existing simplified nonlinear plunging/pitching 2D aeroelastic model accounting for structural nonlinearities and a quasi-steady aerodynamics capable of describing flutter and post-flutter limit cycle oscillations, ii) implement the ℒ1 adaptive control on the developed aeroelastic system to perform initial control testing and evaluate the sensitivity to system parameters, and iii) perform model validation and calibration by comparing the performance of the proposed control strategy with an adaptive back-stepping algorithm. The effectiveness and robustness of the ℒ1 adaptive control in flutter and post-flutter suppression is demonstrated.

A NEW TEST is described for studying the oxidation stability of automatic transmission fluids (ATF). The test shows an excellent correlation with transmission oxidation tests and points out the importance of time as a variable in such studies. Carefully controlled automobile dynamometer tests have been used to study the shear stability of ATF's. Data are presented showing a comparison of driving conditions, transmissions, and V.I. improvers on shear stability. Results are related to the 50-hr Hydra-Matic durability test. The poor reproducibility of rubber swell measurements on commercial transmission seals is due largely to differences in the rubber compounds. A great improvement in the reproducibility may be made by taking into account the specific gravity of the rubber sample.*

Both “Zytel” nylon resin and “Teflon” tetrafluoro-ethylene resin are being used extensively as bearing materials. Most of these applications have been developed independently and no attempt has been made to collect performance data in order to put future design on a firm basis. Typical data on dry or partially lubricated bearings have been collected from a variety of sources. Work in our laboratories on lubricated bearings made of “Zytel” are reported for the first time. In addition, physical properties of these materials are described. With these properties and the bearing work done to date, it is believed that the selection of the material and the design of bearings can be done with greater accuracy.

Many accidents occur today when distant objects or roadway impediments are not quickly detected. To help avoid these accidents, longer-range safety systems are needed with real-time detection capability and without requiring a line-of-sight (LOS) view by the driver or sensor. Early detection at intersections is required for obstacle location around blind corners and dynamic awareness of approaching vehicles on intersecting roadways. Many of today's vehicular safety systems require short LOS distances to be effective. Such systems include forward collision warning, adaptive cruise control, and lane keeping assistance. To operate over longer LOS distances and in Non-LOS (NLOS) conditions, cooperative wireless communications systems are being considered. This paper describes field results for LOS and NLOS radio links for one candidate wireless system: 5.9GHz Dedicated Short Range Communications (DSRC).

A Web-based version of the aircraft design program ACSYNT has been created. “Web-ACSYNT” provides the user with a familiar user interface and is accessible from multiple platforms. Analyses are based upon a set of baseline aircraft models which can be modified through a carefully selected set of parameters related to weight, aerodynamics, propulsion, economics, and mission. The software is intended to become one of the models that comprise the Aviation System Analysis Capability (ASAC) currently being developed by NASA under the Advanced Subsonic Technology (AST) program.

This paper demonstrates the possibilities of using Automotive waste plastic material from “end of life” vehicles (ELVs), in the Footwear Industry to manufacture shoe components. The study establishes the sustainability of the flow of ELVs, from the European Car Parc and identifies and estimates the quantity of plastic materials potentially available for recycling from ELVs. Four potential materials, Acrylonitrile/butadiene/styrene (ABS), Polypropylene (PP), Polypropylene/ethylene/propylene/diene (PP/EPDM) and Polyamide (PA), were identified and three materials (PP, PP/EPDM and ABS) were reprocessed from ELV components and evaluated by the Footwear Industry. As a result, ABS was recommended as an economically, suitable replacement for HIPS, the current material used for manufacturing shoe heel components.

For the past four years the San Francisco Fire Department has owned and operated an American La France Triple Combination Engine Company powered with a Boeing Model 502 gas turbine engine. This engine company, in first line fire service, has illustrated the practicability of the gas turbine in vehicular applications. The purpose of this paper is to outline the experience gained by the use of a gas turbine engine in such an installation.

Many newer commercial vehicles have an event data recorder (EDR) that can record pre-event and post-event speeds. The EDR is incorporated into the engines electronic control module (ECM). In this study, the accuracy of the ECM-reported speed was tested during acceleration, gear shifting and braking at speeds between 16 and 88 km/h (10 to 55mph). The ECM-reported speed was compared to the speed measured by a calibrated optical 5th wheel. The results showed that the accuracy of the ECM-reported speed matched closely during acceleration, cycled to periods of under-reporting the speed during hard braking due to the ABS brake function, briefly under-reporting the speed after letting off the throttle for braking or gear shift and briefly over-reporting the speed near the end of a gear shift phase. This study also looked at calibration factors of the ECM and their effect on the ECM-reported speed.

An unique bonding mechanism was studied after several instances, where the linings stuck to the brake drums on transit buses, were reported. Evidences suggested that the linings were “glued” to the brake drums surface after wear debris (dust) was turned into “adhesive paste” through complicated thermal and chemical changes. Factors such as the friction materials, environment and service conditions, which could activate and deactivate the lining bonding, were observed and discussed. The prevention measures are proposed.

Proper lubrication of moving parts is a critical factor in internal combustion engine performance and longevity. Determination of ideal lubricant change intervals is a prerequisite to ensuring maximum engine efficiency and useful life. When oil change intervals are pushed too far, increased engine wear and even engine damage can result. On the other hand, premature oil changes are inconvenient, add to vehicle maintenance cost, and result in wasted natural resources. In order to determine the appropriate oil change interval, we have developed an oil condition sensor that measures the electrical properties of engine oil, and correlates these electrical properties to the physical and chemical properties of oil. This paper provides a brief background discussion of the oil degradation process, followed by a description of the sensor operational principles and the correlation of the sensor output with physical and chemical engine oil properties.

As part of an overall effort to support the National Highway Traffic Safety Administration's (NHTSA) national program to increase seat belt usage, General Motors instituted an employe seat belt use incentive program at the General Motors Technical Center in Warren, Michigan. This program was responsible for raising seat belt use at the Tech Center from 36% to 70% during its 5 1/2 month duration. The program was patterned, in part, after research work done by professor E. Scott Geller of the Virginia Polytechnic Institute and State University under a grant from the General Motors Research Laboratories and a program conducted by Berg Electronics (a DuPont subsidiary). The intent of the program was to provide sufficient positive incentive to employes to buckle up for an extended period of time, thereby establishing a seat belt use habit that will continue after the incentives are no longer offered.

The onboard “SODART” telescope silicon detector cooling system of the “Spectrum-X-Gamma” observatory, which is designed for the space objects X-ray radiation study, is described. The scale-down model of the passive cooling system description and thermal vacuum test results of this model are given. In the real cooling system the minimal detector temperature at 300 mW heat release is expected about 107 K.

There are many different vibration sources in a car. Engine, gears, road roughness, impacts against the wheels cause vibration and sound that can decrease the parts and the car durability as well as affect drivability, safety and passengers and community comfort. In 4×4 cars, some extra vibration sources are the parts responsible for transmitting the torque and power to the rear wheels. Each of them has their own vibration modes, excited mostly by its imbalance or by the second order engine vibration. The engine vibration is a very well known phenomena and the rear driveshaft is designed not to have any vibration mode in the range of frequencies that the engine works or its second order. The imbalance of a driveshaft is also a design requirement. That means, the acceptable imbalance of the driveshaft is limited to a maximum value.

This paper presents, chemistry, test data and processing procedures on a non toxic and environmentally friendly chrome-free conversion coating alternative with the same level of adhesion and secondary corrosion resistance as that found in chrome containing conversion coating systems. Test data from military and independent sources will be presented on secondary coating adhesion, electrical conductivity, filiform and neutral salt-spray corrosion resistance as compared to chromate based systems .on magnesium, aluminum and zinc and their respective alloys. The European “RoSH” initiative will not allow for the presence of any hexavalent chromium on imported electrical components as of July first of 2006. Trivalent chromium based systems generate hexavalent chromium due to the oxidation of the trivalent chromium and as such will not be allowed.

The “Rigidization-on-Command”™ (ROC™) resin development has focused on the development of resin systems that use UV light cure for rigidization. Polymeric sensitizers have been incorporated into the resin formulations to promote cure using Pen-Ray lamps and UV light-emitting diodes (LED's). Formulations containing the polymeric sensitizers were examined by FTIR and DSC. Complete cure was observed after 15 min. exposure with the Pen-Ray lamps. Performance of the Pen-Ray lamps and UV LEDs was thoroughly characterized. Thermal models were developed to optimize the performance of the of the MLI insulation thermal oven used for orbital cure of the boom. Results show that -12°C is the lowest temperature required for cure of the ROC™ resin systems.

This paper presents a fatigue criterion based on stress invariants for the frequency-based analysis of multiaxial random stresses. The criterion, named “Projection-by-Projection” (PbP) spectral method, is a frequency-based reformulation of its time-domain definition. In the time domain PbP method, a random stress path is first projected along the axes of a principal reference frame in the deviatoric space, thus defining a set of uniaxial random stress projections. In the frequency-domain approach, the damage of stress projections is estimated from the stress PSD matrix. Fatigue damage of the multiaxial stress is next calculated by summing up the fatigue damage of every stress projection. The criterion is calibrated on fatigue strength properties for axial and torsion loading. The calculated damage is shown to also depend on the relative ratio of hydrostatic to deviatoric stress components.

A large number of testing procedures have been developed to ensure vehicle safety in common and extreme driving situations. However, these conventional testing procedures are insufficient for testing autonomous vehicles. They have to handle unexpected scenarios with the same or less risk a human driver would take. Currently, safety related systems are not adequately tested, e.g. in collision avoidance scenarios with pedestrians. Examples are the change of pedestrian behaviour caused by interaction, environmental influences and personal aspects, which cannot be tested in real environments. It is proposed to use augmented reality techniques. This method can be seen as a new (Augmented) Pedestrian in the Loop testing procedure.