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The effect of variation in fuel composition on exhaust emissions from a single-cylinder engine has been studied with eleven different fuels. Exhaust emissions, at fixed engine speed and load, were measured over a range of air-fuel ratio (A/F) settings. At identical A/F values, CO, HC, and NO emissions varied significantly from fuel to fuel. At the same equivalence ratio (ϕ), CO emissions were identical for all fuels. However, at fixed ϕ values, both NO and HC decreased with increasing fuel hydrogen-to-carbon ratio.

Among the most pressing needs in the development of rational approaches for vehicle handling quality evaluation is a method for relating the driver's actions with the car's performance capability. This paper describes a concept which provides a graphic and objective measurement of this relationship, including the effect of road surface conditions on overall system behavior. Based on a continuous plot of the vector acceleration of the vehicle in the horizontal plane, the resultant figure, which is called a g-g diagram, is shown to be useful for characterizing the vehicles's envelope of performance, the variation of this envelope with tire-road surface conditions, the accessibility of various operating points to the driver in performing a task, performance margins utilized by the driver in normal operation, and for several other applications.

This paper describes an investigation that was undertaken to evaluate the lateral forces and moments produced on a vehicle with large, flat lateral faces when it is passing or being passed by a large vehicle in an adjacent traffic lane. The forces and moments were determined from tests that were conducted in the University of Tennessee subsonic wind tunnel. They were, then, input to a computerized vehicle model to find the resulting dynamic response of the vehicle. These forces and moments were sufficiently strong to produce a significant lateral deviation from the desired path of the vehicle. Resulting from this investigation, several recommendations were made to improve highway safety.

Direct impact to the larynx is usually prevented in accidents by the protective nature of the chin. In some situations, the occupant motions leave the larynx unprotected and susceptible to impact by the steering wheel rim or instrument panel. As one of the unpaired vital organs of the body, there is no easy way to provide an alternative for its functions when the larynx is lost or damaged. Information available on the tolerance of the unembalmed human larynx to force is quite limited. This paper describes a multidisciplinary study to determine the response of unembalmed human larynges to blunt mechanical loading and to interpret the response with respect to clinical data. Fresh intact larynges were obtained at autopsy and tested at either static or dynamic loading conditions utilizing special test fixtures in materials-testing machines. Load and deformation data were obtained up to levels sufficient to produce significant fractures in both the thyroid and cricoid cartilages.

A study of all aspects of noise generated by small indirect injection diesel engines has been made, primarily aimed at the reduction of idling noise. This is a major problem in the application of diesel engines to taxis and light commercial vehicles when compared with the gasoline engine. The inherent advantage shown by the indirect injection system, in terms of smoke, noise, and gaseous emissions, is resulting in an extension of its application into larger commercial vehicles. Combustion is shown to be the major noise source under both idling and high-load, high-speed conditions, and means of reducing this by control of fuel injection are described, together with the reduction of the other noise sources contributing to the annoyance aspect of idling noise.

The fundamental effect that cycle difference of a reciprocating internal combustion engine has on noise and performance, together with noise and vibration characteristics of 2- and 4-cycle diesel engines, is described. Some of the conclusions drawn from extensive noise and vibration measurements include: 1. Variation in engine surface vibration and noise radiated is linearly related to a force input applied to the structure. 2. A method of predicting combustion noise levels of current automotive diesel engines. 3. A combination of engine performance calculations with relations for predicting overall engine noise in initial design stages.

Ford Motor Company entered into a contract with the U.S. Department of Transportation in July of 1971, to develop, build and deliver one ESV prototype within a period of 18 months. We fulfilled this obligation, through the efforts of many people and organizations within Ford Motor Company, with the delivery of one fully-styled and functional ESV prototype to the DOT on December 19, 1972. At this time, the Ford ESV is undergoing testing at the Dynamic Science Test Facilities in Phoenix, Arizona. These tests will culminate with a 50 mph barrier crash scheduled for May of this year. Our presentation today will include a brief review of the final design configuration of the Ford ESV, followed by a report of the results of significant crash tests and performance tests in the "crash avoidance" category.

This paper reviews preliminary specifications and goals for a 3,000 pound class U.S. experimental safety vehicle. The ESV program has planned to address four weight classes of experimental safety vehicles to span the vehicle mix represented on U.S. highways. The 4,000 pound family sedan was logically to be followed by a 3,000 pound weight class. The 3,000 pound ESV will be used to assess the effectiveness, practicality and achievability of safety design concepts to be mass- produced in the vehicles of the 1980's. In selecting this vehicle, major consideration was given to vehicle mix, energy, resources and pollution problems

General Motors completed development and testing of its Experimental Safety Vehicle prototypes in May 1972. Two ESV prototypes and two ESV's rebuilt after testing were delivered to the National Highway Traffic Safety Administration for its independent test and evaluation. The GM-ESV designers produced a vehicle close to contract specifications for accident avoidance and occupant crash protection. The vehicle, however, was seriously overweight. The purpose of this report is to comment on the results of the first ESV program, to add comments to the recently published 3,000 pound intermediate ESV and to suggest areas for additional research in highway safety

This paper describes the results of development and evaluation of the Toyota ESV prototypes. Baking, steering, handling, and visibility are outlined. Crash injury reduction, structural crashworthiness and occupant protection requirements are included. The Toyota ESV is equipped with a newly developed, high performance service brake system composed of dual-circuit, four wheel discs, anti- skid systems and hydraulic booster.

Laws controlling noise and the role of various local, state and federal agencies must be balanced against their respective interests, limitations of technology and environmental goals. Past attempts to control noise sustain the need for a balanced approach. The interest of obtaining realistic, uniform standards which are enforced by realistic, uniform procedures will advance the cause of noise control. Inconsistent standards and enforcement procedures will only impede effective noise control.

Socio-aesthetic forces are among the most influential determinants of urban form in present day society. These forces derive from a brief period of history still dominated by the Romantic, Picturesque, point of view. Regional and urban planners, victims of this aesthetic approach, currently provide fixed solutions and unmanoeuvrable transportation networks. An evolving society requires a network system that can respond to its development. The multivariate system of network reserves, justified in this paper, claims a capability of maximum response to change, with maximum adaptability to existing urban forms. It calls, however, for an espousal of monotonic socio-aesthetic principles opposed to those at present endemic in society.

Environmental quality indices gain favor as means to express mathematically the status of the environment. One stress indicator points to pesticides as the top current cause of pollution stress. Using DDT as the example pesticide, the unanticipated phenomena encountered with DDT usage such as non-target kill, genetic resistance, biological magnification and other side effects are described. Transportation is heavily involved not only with the use of pesticides but with the problems of air pollution and the use of heavy metals. Cautions are presented based on the DDT experience, particularly regarding the often too narrow base of a science to support broadly applied technology.

Concern over noise emissions has increased significantly. This paper relates the noise emission problem to other pollution efforts and defines alternative abatement strategies. Major technical and economic parameters are discussed based on the present state-of-the-art. A balanced approach to noise abatement is suggested.

Pollutants are emitted into the atmosphere by both industrial and natural processes. Natural processes also remove these pollutants from the atmosphere, but when total emissions exceed the capacity of natural sinks, the quality of the air decreases. Air pollution can cause severe damage to plants, animals, and microorganisms. Air pollution can also cause subtle damage to the biosphere, as manifested by growth retardation, acceleration of aging processes, alterations in reproductive potential and genetic constitution, and alterations in host-parasite relations. However, air pollutants may serve some beneficial roles, such as satisfying some nutrient requirements of plants. Field studies, however, indicate that the environment, in general, is adversely affected by atmospheric pollution. Unfortunately, only speculations on ecologic ramifications of air pollution are possible with the present level of knowledge.

Trucks are the major source of noise on our streets and highways, affecting the sleep and sanity of millions of city and suburban residents. Truck noise sources are many, but mainly are engine and tires. Since the automotive and trucking industries have not volunteered to quiet truck noises, the Federal government will have to legally require they do so.

From various sources of information it is clear that truck noise is a definite public nuisance. Early noise control efforts were very productive in that many heavy duty trucks did not have mufflers, and the addition of this device made clear improvements. Further improvement requires treatment of many sources significant to the overall level. It is felt that today's “tight but attainable” 88 dBA for heavy trucks can reduce to 86 dBA by 1975 and 8k dBA by 1978 with a lot of hard work. There is promise for meaningful noise regulation in the “real world” as indicated by “calibratability” of non-standard sites.

Construction noise accompanying the rehabilitation of old and the development of new transportation modes is extremely destructive to the quality of life, and the environment. With few exceptions, industry has failed to internalize the cost of unmuffled equipment and procedures, and the cost of this intense noise exposure is an “external cost” borne by both the worker and the exposed public. Engine equipment manufacturers, contractors, and project sponsors resist design for quiet. Engineers have an ethical imperative to protect the noise receiver. Citizen demand for quieter construction is growing and a few manufacturers are voluntarily marketing quieter compressors and paving breakers. Government, on all levels, is beginning to raise the question of unlimited noise emissions. The Walsh Healey noise exposure limits are now applicable to construction operations.