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Handicapped people can be taught to drive. This paper stresses the “family car” concept. If possible, the car should be adapted with special controls for the handicapped that do not preclude the car being driven by the able-bodied family members. Considerable attention is given to existing optional equipment that will assist the handicapped in performing the driving task. The ultimate goal for the handicapped is complete independence: enter the car, perform the driving task, and exit the car unassisted.

From time to time, over many years, MIRA (the Motor Industry Research Association) has carried out surveys of the handling behaviours of various classes of road vehicles. The most recent investigation has concerned modern European intercity buses, or coaches as they are termed in Britain. The work was sponsored by the British Government together with five vehicle manufacturers who each supplied one bus. The main aim of the work was to ascertain the handling characteristics of a sample of modern buses in terms of both absolute behaviour and relative behaviour compared to other classes of road vehicles. However, the manufacturers sponsoring the work were also very interested to discover any correlation between various features of layout of the vehicles and the handling characteristics.

The purpose of this paper is to discuss handling in the context of those operational variables and vehicle chassis considerations which are most significant in affecting the handling properties of light trucks. In discussing handling for normal driving the Cornering Compliance Concept is used to combine the most significant parameters in a simple lumped parameter model. Limit handling performance and the mechanics of rollover are discussed in the paper. It is observed that exposure to limit handling maneuvers is unlikely to occur in normal driving. The significance of vehicle handling properties to highway safety is an unknown at this time.

Due to the challenges in quantifying hand loads in manufacturing environments it is often assumed that the load is evenly distributed between the hands, even when handling parts with non-uniform mass distribution. This study estimated hand loads for six female subjects, when handling a custom part in 8 different configurations (2 weights, 4 CofM locations). The calculated hand loads varied from 20 to 50% of the weight being handled. The magnitude of asymmetrical hand loading depended on both the part orientation and the location of the CoM. Based on this study the knowledge of part weight, CofM location and hand positioning will allow the users of digital human models to perform more realistic and reliable task analysis assessments as the force distributions will be more representative of the actual loading rather than simply assuming the load is evenly distributed between the hands.

In the United Kingdom the impact of recently joining the Common Market has been considerable. The requirement to follow Common Market Directives has produced a situation where the new harmonized laws will eventually supersede the old. The new directives which will take some years to become fully effective are aimed at eliminating the barriers affecting the operation of commercial vehicles which have divided Europe in the past and the inauguration and implementation of a common transport policy. Widely different regulations are viewed as very serious barriers in trade in Europe and, indeed, on a worldwide scale they are becoming very serious barriers to international trade. The difference between the rule-making procedure in Europe and the United States is explained, and the interesting and important differences between the European Type Approval system as compared with the American self-certification procedure are discussed in some detail.

During the mid-1970s, the US embarked on a modest but highly focused effort to demonstrate an aircraft possessing a very low radar signature and sufficient performance to have operational utility. Known as Have Blue, the project was highly successful and led to the F-117 A. This paper discusses issues associated with reducing radar signature to very low levels (levels that are “tactically meaningful,” e.g., capable of defeating realistic threat systems). Radar phenomena and the concept of radar cross section (RCS) are briefly summarized and RCS reduction techniques as they were applied to Have Blue are described. RCS reduction considerations and techniques pioneered by Have Blue have become an integral component of the combat aircraft design process over the past two decades.

Carbon dioxide (CO2), a natural product of human metabolism, accumulates quickly in sealed environments when humans are present, and can induce headaches, among other symptoms. Major resources are expended to control CO2 levels to concentrations that are tolerable to the crews of spacecraft and submersible craft. It is not practical to control CO2 levels to those found in the ambient environment on earth. As NASA looks ahead to long-duration missions conducted far from earth, difficult issues arise related to the management and effects of human exposure to CO2. One is the problem of “pockets” of CO2 in the habitat caused by excess generation of the gas in one location without a mechanism to purge the area with fresh air. This results in the crew rebreathing CO2 from their exhaled breath, exposing them to a much higher concentration of CO2 than whole-module measurements would suggest. Another issue is the potential increased sensitivity to CO2 in microgravity.

The disturbingly high estimate of single vehicle automobile accidents felt to be drowsiness-related has suggested the need for physiologic or behavioral alertness indicators. This experiment is one phase in the systematic evaluation of the reliability of heart rate variability (HRV) as such an indicator. Nine subjects became spontaneously drowsy in a passive laboratory situation, while heart rate (HR), EEG, and other physiologic measurements were recorded for 1 h. Beat-to-beat heart activity in 40 s of waking record was compared with heart activity in 40 s of adjacent drowsy record, using electrographic definitions of waking and drowsy (transitional) states. Of three descriptors of heart activity, HRV only as measured by the mean square of HR, showed an inverse, but marginally significant and unreliable relationship to drowsiness onset. Neither HR nor HRV measured by mean square of successive differences of HR showed any relationship to drowsiness onset at all.

To exercise management control, there must be a realistic program for the guidance of human nature, for communication and reaction to change affect different individuals in different ways. Communications must be molded to meet the program's needs. Reaction to change, supported by communications, will affect both individual and group judgment. The success in resolving the problem of organizational control rests solely with the men who are directly responsible for the program. This paper discusses organizational techniques, methods of program development, and the psychological aspects of management control.

This paper will describe a patent-pending approach of using a vapor compression system to also provide a forced two-phase indirect heat transfer loop. This system can be configured with water boiler peak cooling thermal control hardware to avoid the high ambient temperatures associated with supersonic low altitude flight. Due to the very short duration of this high ambient condition, water boiler transient cooling techniques have potential. The water boiler can also be used for ground based cooling when flight-line ground cooling carts are unavailable. The use of a PID controller to accurately control the cold plate temperatures when used with a solenoid activated by-pass circuit will be described.

The heat transfer coefficient of the car's body is one of the parameters controlling the heat balance inside the passenger compartment under steady state and transient conditions. Applying the analogy to the heat exchanger, the heat transfer coefficient of a car can be measured with no regard to the inhomogeneity of the heat transferring surface. A formula connecting the heat transfer coefficient with driving speed and ventilation air flow is derived from experiments, which holds for the three classes of cars considered.

A method of augmenting natural convection, low-Reynolds-number single-phase forced convection and boiling heat transfer by using nanotube coated heat transfer surfaces is described, as well as a unique method of growing these nanotube surfaces from the heat transfer metal alloy, thereby achieving excellent adhesion. This paper discuses side-by-side experiments where nanotube coated and uncoated surfaces are compared. Data on the positive effects of nanotube coating the axial grooves of copper-water heat pipes is also included. Applications for this technology include improved natural convection heat sinks, enhanced boiling surfaces and improved heat pipes. The nanotube coating is also demonstrated to be a low-cost coating and has been successfully grown on several alloys.

A heated windshield product has been developed which closely matches ideal criteria for this product. The many elements of the system are balanced to realize clearing performance, low reflection, high transmission, a good visual impression, and manufacturability at low cost. The core of the development is a coat-flat-and-bend approach in the thin film technology. The approach to this development, attributes of the process, and properties of the final product are described.

The various factors which should be considered if optimum engine life and performance are to be achieved are discussed in this paper. These factors include ratings or work capacity of the engine, the particular application of the engine, adjusting power output to suit the application, use of torque converters in conjunction with the engine, torsional vibrations, and flywheel size. Examples are presented for each factor, as are mathematical computations and graphic data.

SwRI has developed a new technology concept involving the use of high EGR rates coupled with a high-energy ignition system in a gasoline engine to improve fuel economy and emissions. Based on a single-cylinder study [1], this study extends the concept of a high compression ratio gasoline engine with EGR rates > 30% and a high-energy ignition system to a multi-cylinder engine. A 2000 MY Isuzu Duramax 6.6 L 8-cylinder engine was converted to run on gasoline with a diesel pilot ignition system. The engine was run at two compression ratios, 17.5:1 and 12.5:1 and with two different EGR systems - a low-pressure loop and a high pressure loop. A high cetane number (CN) diesel fuel (CN=76) was used as the ignition source and two different octane number (ON) gasolines were investigated - a pump grade 91 ON ((R+M)/2) and a 103 ON ((R+M)/2) racing fuel.

A technology path has been identified for development of a high efficiency, durable, gasoline engine, targeted at achieving performance and emissions levels necessary to meet heavy-duty, on-road standards of the foreseeable future. Initial experimental and numerical results for the proposed technology concept are presented. This work summarizes internal research efforts conducted at Southwest Research Institute. An alternative combustion system has been numerically and experimentally examined. The engine utilizes gasoline as the fuel, with a combination of enabling technologies to provide high efficiency operation at ultra-low emissions levels. The concept is based upon very highly-dilute combustion of gasoline at high compression ratio and boost levels. Results from the experimental program have demonstrated engine-out NOx emissions of 0.06 g/hp/hr, at single-cylinder brake thermal efficiencies (BTE) above thirty-four percent.

To prevent trunk lid slam noise, reactive openings are used in the trunk cavities of passenger vehicles. In sedans, the trunk cavity and the cabin cavity are coupled acoustically through the discontinuities on the parcel shelf and/or the rear seat. In such a case, these openings behave as necks of a Helmholtz resonator, which in turn change the acoustic response of the system. In this study, the Helmholtz resonator effect of the trunk cavity is discussed analytically through a simplified cavity model. A case study, where the acoustic response of a sedan is analyzed through a computational model considering the resonator effect is also given. Sound pressure levels show that instant pressure drops and damping effects observed in the acoustic response can be explained with the resonator effect. Results obtained from the computational model of the sedan are verified with the track test measurements.

The Hercules Engines 3.7 Series II diesel engine family consists of multiple model four cylinder, in-line configuration, direct injection, liquid cooled, turbocharged, turbocharged/air-to-air inter-cooled, and naturally aspirated versions of 4.00″ (101.6 mm) bore and 4.50″ (114.3 mm) stroke resulting in a displacement of 3.7 liters (226 in3). The engines were developed to meet 50 state heavy duty emission requirements through 1990 for on-highway applications in Class 2b/3 vehicles (8,500-14,500 lbs/3856-6577 Kg GVW) with ratings up to 125 BHP (93.2 KW) @ 2800 RPM. Other application areas include industrial power units, off highway mobile equipment, military and marine. This paper presents the technical objectives for the 3.7 Series II, descriptions of significant components/systems, design technical approaches, and development efforts undertaken to meet the performance/durability objectives, and the products application capabilities.