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The National Highway Traffic Safety Administration (NHTSA) has developed a lumped mass computer model which simulates the interaction of a struck car door and an adjacent two dimensional seated dummy in side impacts. This model was used to investigate the effect of various vehicle design parameters on occupant responses and to define various methods to improve vehicle safety performance. This paper discusses the effectiveness of door padding and side structural stiffness to minimize potential for occupant thoracic injuries in 90° side impacts. Occupant response data were obtained with the aid of the computer model for a Moving Deformable Barrier striking a car at lateral velocities of 25, 30 and 35 mph. To determine the optimal padding and structure needed to minimize potential occupant injury, the Thoracic Trauma Index (TTI) was mapped in terms of different levels of struck car side stiffness and padding characteristics.

A demonstration program to design, implement and evaluate an in-vehicle navigation and route guidance system with dynamically updated travel time information is being undertaken on a suburban arterial road system in Northeast Illinois. In July, 1991, the Illinois Department of Transportation, Federal Highway Administration, Motorola, Inc., and Illinois Universities Transportation Research Consortium agreed to proceed with the design and test phase of the demonstration program. This phase will design the route guidance system demonstration, implement the software design for the Traffic Information Center and conduct a system test. Detailed plans for monitoring and assessing the system's performance will also be prepared. These designs will guide the studies to be performed during the implementation phase of the demonstration program expected to commence in 1993.

The INTEGRATION simulation model is being enhanced and applied at Queen's University, on behalf of General Motors Research Labs, as a tool to perform a dynamic traffic simulation study of the TravTek route guidance experiment in Orlando, Florida. While there were several different ways in which the INTEGRATION model itself was adapted, to be able to model the dynamic and route guidance features of the TravTek system, this paper focusses specifically on describing the associated dynamic modelling routines which needed to be modified and/or developed in order to generate the dynamic inputs to the INTEGRATION model.

Induction noise, which radiates from the open end of the engine air induction system, can be of significant importance in reducing vehicle interior noise and tuning the interior sound to meet customer expectations. This makes understanding the source noise critical to the development of the air induction system and the vehicle interior sound quality. Given the ever-decreasing development times, it is highly desirable to use computer-aided engineering (CAE) tools to accelerate this process. Many tools are available to simulate induction noise or, more generally, duct acoustics. The tools vary in degrees of complexity and inherent assumptions. Three-dimensional tools will account for the most general of geometries. However, it is also possible to model the duct acoustics with quasi-three-dimensional or one-dimensional tools, which may be faster as well.

To improve urban air pollution, stringent emissions regulations for heavy-duty diesel engines have been proposed and will become effective in Japan, the EU, and the United States in a few years. To comply with such future regulations, it is critical to investigate the effects of intake and injection parameters and fuel properties on engine performance, efficiency and emissions characteristics, associated with the use of aftertreatment systems. An experimental study was carried out to identify such effects. In addition, the KIVA-3 code was used to gain insight into cylinder events. The results showed improvements in NOx-Smoke and BSFC trade-offs at high-pressure injection in conjunction with EGR and supercharging.

With the increasing use of complex electronics in automobiles, diagnosis of failures (including calibration shift) of components has become a major issue. This paper presents a method which has the capability of diagnosing failures of any component at any level of failure for automotive electronic systems. The method presented here is based upon mathematical models for the system under diagnosis. These models are run onboard the vehicle in a digital computer and implemented with such highly efficient algorithms that real time diagnosis is possible onboard the vehicle. Although the details of the method are specific for failures in each major class of component (e.g. sensor, actuator, controller), this paper demonstrates that any failure which can be represented in the model can be diagnosed uniquely and distinguished from other failures.

This research was carried out by INRETS (France) using the Daimler-Benz driving simulator (RFA), in order to analyse the behaviour of 49 drivers, when faced with an unexpected emergency situation at a junction. This experiment enables us to collect driver reaction times, and to validate our previous work dealing with the choice of an emergency manoeuvre. Most drivers resorted to braking. Only 1 out of 5 drivers succeeded in avoiding the collision, whereas an appropriate and correctly performed manoeuvre, in particular a wider use of lateral swerving, would have allowed a higher success rate. The advantage of ABS, the influence of the obstacle movement with regard to the outcome of the emergency situation, and the poor benefit obtained by reducing reaction times are also discussed. Therefrom the main objective of driving aid devices should be to prevent the driver from being faced with such a situation.

Effusion cooled combustor designs for gas turbine engines offer improvements over traditional cooling approaches. The effusion technique, also known as transpiration, or multi-hole, employs minute cooling passages through the wall to be cooled. Effusion cooling provides increased cooling effectiveness, enabling higher performance. Additionally, effusion cooling offers manufacturing benefits, due to its simplicity of design, which result in decreased cost. The design also provides many challenges due to the enormous number of cooling holes required in an effusion cooled component. Candidates for hole drilling, laser and electron beam drilling, are compared with respect to methodology, equipment, hole characteristics, and economics.

A system has existed since the early 1960's to provide U.S. industry access to NASA's reservoir of technology. This paper describes the process used by the NASA sponsored Aerospace Research Applications Center (ARAC) to implement technology transfer. Five years worth of surveys conducted for clients from the automotive industry are reviewed. Both ARAC and client assessments are analyzed to determine the effectiveness of the process. Client surveys are divided into nine categories, the most frequent being technology assessment. Utilization of NASA's (1) RECON database, (2) technology and (3) counselors is identified. The highest client-rated projects are reviewed. Specific cases are discussed; they illustrate that technology transfer goes beyond simple literature searches.

A cyclic two-step process is described which forms the basis for a simple and highly efficient air purification technology. Low molecular weight organic vapors are removed from contaminated airstreams by passage through an optimized sequence of sorbent media layers. The contaminant loaded sorbents are subsequently regenerated by thermal desorption into a low volume inert gas environment. A mixture of airborne organic contaminants consisting of acetone, 2-butanone, ethyl acetate, Freon-113 and methyl chloroform has been quantitatively removed from breathing quality air using this technique. The airborne concentrations of all contaminants have been reduced from initial Spacecraft Maximum Allowable Concentration (SMAC) levels to below the analytical limits of detection. No change in sorption efficiency was observed through multiple cycles of contaminant loading and sorbent regeneration via thermal desorption.

The medium duty commercial vehicle “ISUZU FORWARD” powered by the newly designed 6HE1 six cylinder engine was placed on Japanese market in April 1990. At the same time the engine family of the four cylinder version 4HF1 engine mounted in the light duty commercial vehicle “ISUZU ELF” was introduced in Japanese market in August 1990. These H-series engines are successors to the B-series engines, which have been used worldwide for vehicles, industrial machinery and boats. The basic structure of OHC and ladder frame of these engines made it possible to improve the design of the inlet and exhaust ports and valves, and improve the stiffness of the cylinder block and the cylinder head. In turn this provides higher performance, durability and reliability. This paper describes the special features and construction of these new H-series engines, together with newly adopted technology.

Styrene Maleic Anhydride (SMA), typically glass reinforced, is widely used in automotive for interior trim and instrument panels. However presently available materials are not able to fill all of the increasing demands for both toughness and temperature resistance that are being required by automotive OEM's due to higher quality requirements, passive restraint legislation, and increased global competition. This paper will review a new family of SMA's that, due to differences in the manufacturing process and formulation, are available with a wider window of available temperature resistance and toughness properties. The properties of these materials will be reviewed along with comparisons to other materials such as existing SMA's, polycarbonates, modified poly phenylene oxides/ethers, ABS and other commonly used plastics for interior trim applications. Interior applications, along with their requirements, where these materials have found use will also be reviewed.

Since 1966 the federal government, through the National Highway Traffic Safety Administration, has promulgated regulations governing the crash safety of motor vehicles, with particular attention to passenger cars. However, during the next four years, most of the regulations will also apply to light trucks and vans. There are now 53 Federal Motor Vehicle Safety Standards (FMVSS). These standards primarily regulate the safety of new vehicles. For many disabled persons, especially those confined to wheelchairs, vehicles must be extensively modified to allow them to drive, or to ride as passengers. The objective of this paper is to examine the safety level intended to be afforded to able bodied persons by the crashworthiness FMVSS and to make observations on the special requirements of modified vehicles to afford the same level of safety to disabled persons. We will emphasize the safety needs of those who use vans since vans are the vehicles most extensively modified.

Forty-five drivers of late model cars equipped with advanced driver-information systems (trip computers, phones, etc.) participated in 4 focus groups, 2 in Los Angeles and 2 near New York City. The purpose of the groups was to determine driver attitudes toward existing, high-technology, driver-information systems and what drivers might want in future cars. Drivers wanted systems that would give them (1) advance information about vehicle malfunctions (such as a warning about low oil, not just a failure light) and (2) navigation information. Drivers complained about current systems that divert their attention from driving, especially entertainment systems (“the buttons are too small”) and cellular phones (drivers weaving in traffic). There were reports of accidents and near accidents associated with use of in-vehicle systems and maps.

It is unavoidable that a DI diesel engine exhausts a blue and white smoke at starting, especially in the cold atmosphere. In the experiments presented here, a small DI diesel engine started under the conditions of coolant and suction air whose minimum temperatures were 255 K and 268 K, respectively. The flame was photographed by high-speed photography, the temperature of flame and the soot concentration were measured by two-color method, and CO2 concentration was detected by luminous method. The engine cannot be started over several cycles when the coolant temperature is 255 K and suction air temperature is 268 K. As the temperature of coolant and suction air are decreasing, the maxima of the cylinder pressure, the flame temperature, the soot concentration and CO2 concentration are decreasing. Luminous small dots or small lumps of flame become scattered in the piston cavity.

This paper presents the discussion of the optimal shape for the wire cross section of helical springs. Since the stress at the inner side of a coil is higher than that at the outer side in a helical spring with a round cross section, the mass may be saved through stress equalization by the improvement of the cross sectional shape. Shape optimization is performed by the modification of the cross sectional shape so as to minimize the mass of the helical spring under constraints such as spring rate, coil diameter, applied load and maximum design stress. In the present analysis, stress distributions are calculated by the finite element analysis based on a stress function. In consequence, the optimized shapes are found to be almost oval and the mass is reduced by about 10% for the springs of small spring index.

In the transmission and powertrain divisions of the automotive industry, audible noise transmitted by gear meshing is one of the highest quality characteristics for customer satisfaction. This paper involves an overview of an approach of reducing gear noise in manual transmissions and powertrain components. A traditional method of full factorial experimentation is usually the norm in gear noise development. This method is very expensive, time-consuming, and yields marginal results. The method of Dr. Taguchi's Design of Experiments was implemented on the speed gear pairs of a manual transmission. Different combinations of gear geometry characteristics were tested using design of experiments. Optimum manufacturing tolerances are then set using the results of the experiment. The significance of this type of experimentation is that it results in a substantial reduction in gear noise, as well as reduction in pre-production gear development time and manufacturing costs.

Visual and driving behavior of novice and experienced drivers is investigated when they negotiate the vehicle between standing or moving obstructions (pedestrian and vehicle) on both sides. As the driving tasks became difficult, they sampled the right obstruction at a higher rate than the left one regardless of the position of pedestrian or vehicle. However, the novice drivers whose skill acquisition speed was slow tended to increase their fixation rate for the vehicle's direction of travel. With respect to driving behavior, vehicle speed at the meeting point for the novice drivers was faster than that for the experienced drivers. The novice drivers drove on the right obstruction side systematically irrespective of the driving tasks.

A test program was undertaken to demonstrate that a realistic gasoline could reduce both hydrocarbon mass and reactivity of vehicle exhaust emissions and simultaneously reduce toxics, carbon monoxide, and nitrogen oxide emissions. In order to evaluate the effect of RVP and aromatics, four highly reformulated gasolines were blended from existing refinery streams with RVP at a nominal 8 and 7 psi and aromatics at a nominal20 and 10 vol%. The emissions performance of these fuels were measured in a fleet of ten 1990 California vehicles. When compared to industry average gasoline, each of the four gasoline test blends demonstrated substantial emission reductions in criteria pollutants and toxics. Estimates of the cost and emission benefit of these gasolines were used to evaluate the cost-effectiveness of these formulations for California.

High-rate-reactively-sputtered (HRRS) hard coatings have been deposited on steel rollers. The effects of substrate hardness and coating hardness on the tribological behavior of titanium nitride (TiN) coated steel rollers have been investigated with a roller-on-roller tribo-tester. The properties of both the substrate and the coating were found to be very important in determining the wear performance of the rollers. From experimental results it was noted that the relatively hard TiN coatings enhanced the scuffing-failure-load by ten times when deposited onto relatively hard substrates (Rc 62), but did not improve the performance of soft substrates (Rc 45). For a relatively soft substrate (Rc 45), the benefit of using the relatively soft TiN coating rather than the hard TiN coating has been demonstrated.