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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).

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.

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.

Vehicle dynamics is a discipline of mechanical engineering that benefited of significant improvements thanks to the progress of computational engineering. Vehicle dynamics engineers are using CAE for the development of a vehicle with MBS and FEA. The concurrent use of these two technologies is a standard in the automotive industry. However the current simulation process is not fully efficient because local geometrical and material nonlinearities are not accurately modeled in classical MBS software. This paper introduces a methodology for vehicle dynamics simulation integrating MBS capabilities in one single nonlinear FEA environment enabling an accurate modeling of nonlinearity in vehicles.

MONOGAL is a coated steel developped to improve the corrosion resistance of exposed automotive body applications. Its process os based on the brittleness of the η zinc coating in a range of temperatures below the melting point of the zinc. MONOGAL is produced on a hot dip galvanizing line; at the exit of the pot the free zinc is brushed off the light side of the differentially coated sheet. Side 1 of MONOGAL presents a very thin and continuous layer of iron-zinc diffusion alloy with no free zinc. Side 2 is a standard G90 or G60 zinc coating. The iron-zinc alloy layer has excellent anti-galling properties which improve the formability of MONOGAL over two side hot dip galvanized steel with the same r value. MONOGAL also shows good weldability, paintability and corrosion resistance.

In recent years there has been increasing interest in quantifying the emissions from aircraft in order to generate inventories of emissions for climate models, technology and scenario studies, and inventories of emissions for airline fleets typically presented in environmental reports. The preferred method for calculating aircraft engine emissions of NOx, HC, and CO is the proprietary “P3T3” method. This method relies on proprietary airplane and engine performance models along with proprietary engine emissions characterizations. In response and in order to provide a transparent method for calculating aircraft engine emissions non proprietary fuel flow based methods 1,2,3 have been developed. This paper presents derivation, updates, and clarifications of the fuel flow method methodology known as “Fuel Flow Method 2”.

“DELRIN” is a new thermoplastic which offers high strength, excellent thermal stability, good fatigue life, low creep, and excellent solvent resistance. This paper describes the physical and chemical properties of the material, and the range of possible uses. The material is easily fabricated into complex shapes by standard injection-molding techniques. Also, it can be easily joined to itself or to other materials. The authors think that the material offers advantages over metals in its good fric-tional properties, abrasion resistance, and corrosion resistance.

The present paper describes the system design for the Clear Vision auto defog system and the improvements made to the Integrated Dew Point and Glass Temperature (IDGT) sensor. The Clear Vision auto defog system has been implemented on a 2000 Cadillac DeVille. Preliminary validation tests demonstrate satisfactory performance.

The objective of the development of the aerodynamic drag predictive tool CDaero was for use as a module for the Automobile Design Support System (AutoDSS). CDaero is an empirically based drag coefficient predictive tool based initially on the MIRA (Motor Industry Research Association) algorithm. The development philosophy was to be able to predict the aerodynamic drag coefficient of an automobile with knowledge of the features of the surface geometry control curves. These are the curves that control the 3-dimensional geometry as seen in the profile, plan and front and rear views. CDaero has been developed in a computing environment using the equation solver TKSolver™. Fifty-one input feature values are first determined from the automobile geometry and then entered into the program. CDaero models the drag coefficient with thirteen different components covering the basic body, as well as additional components such as the wheels, mud flaps, etc.

This paper discusses the use of electromechanical devices as the kinematic portions of a microprocessor based gas turbine control system. Specific applications are: 1. An electric motor driven, positive displacement pump, which provides metered high pressure fuel to the distribution manifold. Fuel metering to be provided by varying the motor angular velocity. 2. An electric motor driven lube oil pump. 3. Electromechnical actuators for motion and control of compressor and power turbine variable geometry. 4. A starter/generator integral with the gas generator. Topics covered include: Comparison to conventional hydro-mechanical systems. Response characteristics of the fuel pump and actuator systems. Brushless D.C. motor characteristics. Power electronics requirements for brushless D.C. motors. Control electronics interface with brushless D.C. motor systems. Reliability and maintainability issues. Diagnostic/prognostic enhancements.

Buick engineers are well pleased with their '69 Chassis. Benefits of a unique front suspension camber curve are documented. The effects of various suspension parameters on ride and handling are explained. These were varied independently of one another in the course of evaluating over 30 suspension configurations.

3-D Flow separations such as those that occur on the rear end of a vehicle have an impact on wall pressure distribution, hence on aerodynamic forces. The identification of these phenomena can be made through the analysis of skin friction patterns, which consist of the “footprints” of flow separations. These can be determined from qualitative and quantitative data obtained from near-wall PIV measurements. The wake flow of different configurations of a simplified 1/4 scale car model are analyzed. The influence of the slant angle and the Reynolds number on 3-D separated flow patterns and their induced pressure distribution is addressed, based on near-wall PIV, standard PIV and wall pressure measurements. This enables to understand how a topological change (the size or shape of a separation pattern) modifies the associated pressure distribution (therefore the drag coefficient). Finally, insights into instantaneous topology identification are presented.

Propulsion system control algorithms covering the functional needs of xEV propulsion (‘x’ donates P0-P4 configurations) systems are presented in this paper. The scope and foundation are based on generic well-established HEV controller architectures. However, unlike conventional HEV (series, parallel and power split) powertrains, the next generation of integrated electric propulsion configurations will utilize a single micro controller that supports multiple control functions ranging from the electric machines, inverters, actuators, clutch solenoids, coolant pumps, etc. This presents a unique challenge to architect control algorithms within the AUTOSAR framework while satisfying the complex timing requirements of motor/generator-inverter (MGi) control and increased interface definitions between software components to realize functional integration between the higher level propulsion system and its sub-systems.

THE usefulness of planetary gear trains and the engineering techniques necessary for optimum design are discussed in this paper. A simple method for calculating planetary gear ratios is described which can be used to determine quickly the potential usefulness of any planetary configurations. The author lists criteria which help to evaluate the potential of a planetary gear train schematic from the standpoints of gear noise and structural viewpoint. Detailed design of individual members include spacing of the pinions, mounting considerations, thrust direction, lubrication, and stress evaluation.

THIS PAPER reviews VTOL problems, indicating probable ways toward optimization of whole lifting and propelling system. Also discussed are the power and thrust requirements for optimum cruise and vertical take-offs and landings for propeller-driven and jet-propelled aircraft. Three speed ranges offer the most promise for VTOL aircraft, if thrust requirements for cruise and take-off are to match. The ranges are centered around Mach numbers of 0.65, 0.8, and 2.0+. There is a possibility of overcoming the high thrust needed for hovering by use of bypass augmentation, special hovering jets, or favorable ground effects, the author reports.

THE optimum mode of control for an aircraft engine is dependent on both the configuration of the engine and its application. Each engine application requires several detail modes of control, one for each definable regime of operation of the engine. Discussions of control requirements can be simplified by classifying these regimes by objectives: physical limiting, thrust, and transient control. The turbojet engine is the basis for the discussion in this paper. Acceptable modes of control can often be selected by inspection of the engine and its application. Selection of an “optimum” control mode requires investigation of the operation of the engine and weapons system at every stage of its use. The selection of a “mode” of control requires a compromise between performance and other design factors. The need for simplicity and accuracy must be balanced against the stability requirements. The availability and flexibility of control components may limit the modes of control considered.

STRUCTURAL MATERIALS for Mach 3 jet transports pose difficult problems for the design engineer. Reasons for this problem are the incomplete information available on the many possible metals and the diversity of critical properties that are added by supersonic requirements. The material properties discussed in this paper include tensile strength, resistance to crack propagation, ease of fabrication, weldability, and thermal expansion. Cost factors are also considered. The structural configuration of the wing and fuselage is an example of the complexity of the material selection problem. The wing may be rigidity-critical, and the fuselage strength-critical; each requires diferent material properties to solve the problem.*

NEW WELDING processes are dropping costs while providing improvements in weld quality. This paper describes some of the more promising new developments in pressure and fusion welding and brazing. Included in the discussion are ultrasonic, high frequency resistance, foil seam, magnetic force, percussion, friction, and thermopressure welding and diffusion bonding. The description of adhesive bonding includes the development of glass or ceramic materials as structural adhesives.*

eBrake® (1, 2) - a new “brake-by-wire” technology, was developed at the German Aerospace Centre, DLR e.V.. It is based on an electric powered controlled friction brake with high self-reinforcement capability. To avoid jamming the brake a special control technology was developed. Thus, by intelligently controlling a brake wedge, the kinetic energy of a vehicle is transformed into braking power. Furthermore an advanced design was found to deal with a broad variation of the friction coefficient. The physical effects involved lead to a significant reduction of energy consumption of the brake actuator compared to “conventional” brake-by-wire systems.

THIS PAPER presents the development of the DC-8 suppressor and thrust brake unit from initial test work through the final design. The selection of the production unit was based on a wide background of test work using both model and full-scale facilities. On the basis of this work, the configuration selected for production consisted of a fixed, corrugated, suppressing nozzle with a retractable ejector. A target-type thrust brake, mounted in the ejector, was chosen for the thrust brake production unit. Approximately 12-db suppression and 44% reverse thrust are provided by the unit. The ejector is hydraulically operated and the thrust brake air actuated. Both actuation systems obtain power from the aircraft systems which provides for operation during engine-out conditions. Alternate methods of actuation are provided in case of a primary system failure.