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The development of several automotive engines has been examined from a historical perspective, and important common technology and business-related factors affecting the successful development and introduction of a new technology into the marketplace have been identified. This paper is primarily targeted toward research planners and managers rather than design engineers and technology specialists. It, thus, focuses more on strategic aspects of research planning and ways of achieving successful market introduction than on in-depth analyses of cost/performance parameters. Eight specific engines are selected to cover a wide range of sizes, operating cycles, and successes/failures in the marketplace. Both currently available engines and those not yet commercialized have been included.

This paper provides an overview of Colorado's efforts to reduce particulate emissions from light- and heavy-duty vehicles. As a result of the passage of Senate Bill 193, Colorado has enacted several programs to control diesel emissions. These programs include a roadside opacity enforcement program, a pilot light-duty inspection program, and a public education program. Colorado is in the process of setting up Emissions Technical Centers for purposes of supporting the diesel opacity enforcement program. Currently, they are developing light- and heavy-duty test procedures. Colorado is planning numerous diesel related activities in the future. They will be investigating the relation between opacity and mass emissions, in order to better define correlation between the two indicators. CDH also will be performing much more research into test cycles and will be investigating a light- and heavy-duty I/M program. Considerable amounts of data will be available by next fall.

THE PAPER presents the findings of a combined experimental and theoretical investigation of jet mixing phenomena in quiescent or swirling flow fields, using the hydraulic analogue technique to simulate the Diesel injection process, with particular emphasis on the development of wall jets. The photographic records clearly indicate the propagation and mixing associated with the advancing jet and provide a basis for quantitative analysis of trajectories and entrainment rates. The mathematical models, while based on simplified solutions, nevertheless model the observed processes with satisfactory accuracy.

Ethanol-gasoilne blends have been investigated as a spark-ignition engine fuel. The work was carried out on a Ricardo E6 variable compression engine in which all the significant operating parameters can be varied and accurately measured including onset of knock. Various blends were used (10 to 70% ethanol by volume) and the effects of mixture strength, ignition timing and speed on the highest useful compression ratio were accurately defined. Borderline road test data were evaluated using information on reference fuels and the required performance of the automatic spark advance mechanism was deduced. The results revealed that higher concentration of ethanol in the blend greatly enhances knock resistance. A blend of 50% gasoline and 50% ethanol produced the highest output in both the rich and lean mixture regions. The performance of the automatic spark advance mechanism was found to vary considerably with various blends and mixture strengths.

This standard is applicable to off-road work machines - base machine and its equipment included in categories 1.1, 1.2, 2, 4, and 5 of SAE J1116.

This standard is applicable to off-road work machines, base machine and its equipment, included in categories 1.1, 1.2, 2, 3, and 5 of J1116.

The term "Mobile forestry machines" is intended to include those off-road machines which are designed especially for, or adapted to be used in, the planting, site preparation, harvesting, processing, and transporting of trees. The diversity of machines and systems falling within this scope prohibits detailed specifications, and therefore recommendations are of a general nature.

This standard applies to dumper bodies as defined in SAE J1016 and dumper trailers as defined in SAE J734. It is similar to ISO/DIS 6483.

This document describes the terms or names of the parts, characteristics, and parameters of automotive pull type clutches used in trucks, and of vehicle apparatus or components related to the pull type clutch.

All materials classified as nylons share certain basic characteristics. However, even within the seemingly limited realm of glass fiber reinforced nylons, many levels and combinations of physical, thermal, and environmental resistance properties are available. These properties result from such factors as the following: 1 Type of nylon (6, 6/6, 6/10, 6/12, etc.) 2 Percentage (by weight) of glass fibers 3 Diameter and length of glass fibers 4 Wetting agent used to promote adhesion between resin and fibers (if present) 5 Heat stabilizer (if present) 6 Impact modifier (if present) 7 Pigmentation (if present) In order to select a material with appropriate characteristics, the prospective manufacturer and end user should investigate the proposed application thoroughly, and maintain open communication with the various material suppliers.

Injuries to motorcyclists lead to permanent disability more often than injuries to car occupants (10 percent versus 6 percent). The use of helmets has decreased the risk of head injuries. Other injuries leading to permanent disability are currently concentrated on the extremities (about 70 percent). Almost all are due to fractures located in joints where knees, elbows, shoulders, and ankles are the modest common spots. In a study based on 200 motorcycle accidents, it was shown the existing protective clothing had no effect on the incidence of fractures to knees, elbows, and shoulders. Based on that knowledge, a new motorcycle suit was constructed. The main goal was to find a shock-absorbing material to protect knees, elbows, and shoulders in an accident. Confor Foam, a medium-density urethane foam, was tested and found to possess relevant characteristics.

Pedestrian accidents are a serious problem in many countries, and some form of vehicle design recommendations to improve pedestrian protection are urgently required. Research has shown that in an accident the severity of injury is influenced mainly by impact speed, shape of the car, stiffness of the car components struck by the pedestrian, and the stature and strength of the pedestrian (young or old, frail or strong). A measure of the importance of these variables has now been demonstrated, but limitations, in the performance of dummies and gaps in existing knowledge, particularly a human tolerance, have also been identified. These limitations reduce the precision with which car design requirements for pedestrian safety may be specified. Obtaining further information and proving a test dummy to overcome these limitations may be a lengthy process.

A major cause of serious injury in motorcycle accidents is the rider's leg being trapped between the motorcycle and a car. This paper gives results from a number of full-scale impact tests of motorcycles with and without leg-protecting fairings. Motorcycles were crashed into a flat, rigid barrier inclined at 30° to their direction of travel. Three basic configurations were studied: motorcycles with no leg protection, with hard leg protection that absorbed negligible amounts of energy, and with soft leg protectors that absorbed 5 to 10 percent of the kinetic energy on impact. The use of a leg-protecting fairing substantially reduced damage to a dummy rider's legs in crash tests, and a protector that absorbs some energy seems preferable to one that does not. These results were achieved without increasing the risk of other types of injury

Higher complexity of accident events makes it more difficult to analyze the efficiency of protection measures for pedestrians than for vehicle occupants. Considering the quality of transformation of the results found (dummy quality) as well as their statistical reliability (reproducibility), it is necessary to find a methodically clear solution. The special problem of pedestrian accident simulation will be explained by examples showing the complexity of accident events, by valuation of protection measures, and by the reproducibility and transmissibility of results. Advantages and disadvantages of experimental methods (integrated or component tests) to valuate the vehicle exterior will be shown, using our own test results, as well as results taken from literature. Following this, a procedure is derived. Finally, car design characteristics are described that improve the protection of exterior road users.

The omnibus occupies an important position in the traffic scene in the Federal Republic of Germany; this paper furnishes statistical data on this fact. In the light of the national statistics, it is deduced that the risk of being killed or seriously injured as the occupant of a bus is Sow. This study covers 97 bus accidents with a collision in which occupants were injured: for the bus occupants, the risk of injury is given dependent on the accident opponent and kind of collision. For bus/car accidents, the risk to the car occupants, i.e., the passengers in the opposing vehicle, is also described. Moreover, this paper contains 142 accidents with injuries to the bus occupants without the bus being involved in a collision. These injuries resulted from the driving maneuvers of emergency braking, starting, and driving in a bend.

Automatic belts in Toyota Cressidas have increased belt usage by front-seat occupants of these cars to more than 95 percent. This paper compares the fatal accident experience of these cars with that of the fairly similar Datsun (Nissan) 810/Maxima automobiles (which are equipped with manual belts used by about 20 percent of their occupants). It shows the result of the increased belt usage is a decrease in fatalities among Toyota front-seat occupants. In fatal accidents where no front-seat occupants of the Toyotas or Datsuns are killed, the Toyotas have a higher involvement rate than the Datsuns. Also, on average, the fatally injured front-seat occupants of the Toyotas are 7 years older than those in the Datsuns.

The number of people killed in road traffic accidents in Japan had increased from year to year until 1970 and the number of deaths and injuries recorded in the same year were 16,800 and 980,000, respectively, or a total of nearly 1 million casualties, resulting in the introduction of the phrase "traffic war." Under these circumstances, insuring traffic safety became a top priority social issue, and, as part of a national attempt to cope with this problem, the Fundamental Law Related to Traffic Safety Measures was enacted in 1970. Based on this law, the national and regional governments pursued comprehensive and powerful traffic safety policies and measures in various areas, including the improvement and provision of traffic safety facilities. As a result, the number of deaths and injuries from traffic accidents in 1979 was reduced to approximately 8,500 and 600,000, respectively, the former representing a decrease by nearly half that recorded in 1970.

Thoracic injury to the near side occupant in a side collision is normally caused from contact with the struck vehicle's crushed side structure engaged by the striking vehicle's front end. Extensive research has already been done to investigate the effect that strengthening and padding struck vehicle side structure has on occupant safety. This study investigated the effect that altering the striking vehicle front end characteristics has on occupant safety in a side impact. The National Highway Traffic Safety Administration's (NHTSA) moving deformable barrier (MDB) was used to conduct 12 crash tests. Three different types of honeycomb barrier faces were used, each representing a front end characteristic change. These were a reduction in stiffness, a lowering and tapering of the hood profile, and a lowering of the bumper. The alterations were believed to represent achievable production vehicle changes.

The National Highway Traffic Safety Administration (NHTSA) has tested 12 current production cars in a series of controlled side impacts. As measured by the impact responses of NHTSA side impact dummies, the cars were found to vary dramatically in their capability to provide occupant protection. For the median-aged side-struck occupant, the potential for serious thoracic injury was found to range from a low of 9 percent for the 4-door AMC Concord to a high of 97 percent for the 2-door Nissan Sentra. This paper investigates these differences in safety performance and reports those vehicle design parameters that are key to thoracic side impact protection. From the available data, the study concludes that the design parameter most crucial to occupant protection in side impacts is the Door Effective Padding Thickness (DEPTH).