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A review of the CRC road rating programs conducted between 1952 and 1971 indicates that: 1. Equations based on RON and MON are satisfactory for predicting the road octane numbers of gasolines. 2. MON has become more important and RON less important in prediction equations. 3. Variables such as percent aromatics, Pb concentration, and DON are not broadly significant and improve RON/MON equation predictions only in restricted applications. 4. Car appreciation of low-sensitivity fuels has increased, while appreciation of high-sensitivity fuels has decreased. 5. Road octane response to increase in laboratory octane quality has decreased. 6. Variability of Road octane testing and predictions have remained substantially constant over the past 20 years. 7. Because of variability considerations, measurements of road versus laboratory octane relationships and estimates of car satisfaction are subject to significant errors.

During 1970-1971, 15 organizations participated in a Coordinating Research Council program to compare the influence of unleaded and leaded gasolines on octane requirement increase (ORI). A total of 147 1971 model cars (47 pairs and 53 individual cars) were operated for 8000-20,000 miles using driving schedules prescribed by each participant One car of each pair was run on an unleaded fuel of 91-95 Research octane number (RON) and the other on a leaded fuel of similar quality. For paired cars, the average ORI was 5.8 RON for unleaded and 3.8 RON for leaded fuel cars. The ORI difference of 2.0 RON for paired cars was slightly less than the average ORI difference of 2.5 RON for all 75 unleaded and 48 leaded cars. In a supplemental program, results in 20 cars showed an average ORI difference of only 0.3 RON between unleaded and low-lead fuel cars.

The paper discusses current efforts to increase the compatibility of methods of aiming and inspecting presently used two-beam headlamp systems. The three aiming methods now employed are named, and the requirements and disadvantages of each are presented. Charts indicate the accuracy of each method, and the probability of acceptance of a unit that is aimed mechanically and inspected by another method is determined. Recent work in the field is summarized, and future goals and considerations are noted.

Present vehicle suspensions result in considerable changes in vehicle attitudes with varying loads. These changes can greatly affect headlamp performance. This paper examines the need for accurate headlamp aim and considers the performance requirements of automatic aim-correcting devices and the performance of a specific arrangement now being fitted experimentally to a number of British cars.

A type of V-belt drive which shifts ratios in accordance with input speed and output torque has been successfully employed as the transmission for vehicles ranging from snowmobiles to compact automobiles. Increasing popularity of this kind of transmission has created the need for more reliable criteria to be used in its design. This paper presents a derivation of design equations for a symmetrical V-belt drive in which centrifugal control is governed by an expanding garter spring and torque control results from a helical cam. Experimental results are included which support the validity of these equations.

The separate effects of important variables in vehicle and transmission design are evaluated as they relate to performance, and are given in terms of vehicle speed and wheel torque. The significance of the variables is shown in steady-state gradeability and acceleration performance curves, with speed versus wheel torque plotted on logarithmic scales. The effects of vehicle variables as deduced from this analysis may be used as a basis for predicting performance of various vehicle and transmission designs.

This paper describes the methods taken to effect a step change in passenger car bumper design in order to meet Federal Standard 215, set forth by the Department of Transportation. The basic goal is to achieve a lightweight, low-cost bumper that is compatible with styling and durable enough to suffer little or no damage during impact at 5 mph (8 km/h). Three major areas-bumper design, materials, and fabrication-are treated separately and also as they interrelate. Boxlike sections, utilizing the face bar as an integral stressed member and judiciously employing beads and gussets, give best strength and stiffness Materials should be of highest yield strength compatible with formability, and welded or bonded fabrication, approaching one-piece box construction, results in optimum structural properties.

A new concept in pneumatic energy absorbing bumper systems for motor vehicles has been developed, the dynamic testing of which demonstrates considerable promise in dissipating large blocks of energy in an accident situation. Having a flexible front section molded from a castable elastomer, the pressurized system is equipped with relief valves that open at a predetermined pressure during collision, thus dissipating energy.

Painted and color-pigmented elastomerics, specifically painted microcellular urethane and ethylene propylene terpolymer (EPDM), and painted and color pigmented vinyls are being employed extensively as highly flexible bumper stone deflectors on 1973 passenger vehicles built in the United States. The urethane parts are fabricated by a cast process; the EPDM is extruded, compression and injection molded; and the vinyls are extruded or injection molded. The urethanes and some vinyl are painted by conventional paint processes, whereas the EPDM is treated by a specific surface activation prior to painting. A wide range of colors, including metallics, are used to match the painted body to provide color continuity. On some vehicles, black, argents, and grey colors are employed where the stone deflector is not as highly visible or where a pleasing color contrast is desired.

This program attempted to consolidate data from several sources in an effort to isolate the contribution of wheel travel to overall vehicle mobility. Some definitive data are presented and described. The data indicate that wheel travel of 6-8 in will be capable of addressing 25% of the obstacles encountered, 14 in will address 55%, and 17 in will address 65%. It appears that 30-35 in of wheel travel, which would provide capability for addressing some 75% of encountered obstacles, is a maximum attainable level. This is subject to cost-effectiveness and vehicle configuration constraints. The overriding conclusion is that wheel travel is an intertwined, indivisible vehicle characteristic that must be accompanied by other properly matched vehicle attributes, such as wheel base, spring rate, and damping rate, to attain its full potential. Test data from the M113, PI M113, and MICV were used in support of this evaluation and analysis.

The Federal government requires that all 1973 passenger cars be capable of withstanding a 5 mph front bumper and a 2.5 mph rear bumper fixed-barrier impact without damage to safety related components (lighting, latching, fuel, exhaust, cooling, propulsion, steering and braking systems). Two basic ways in which the impact energy can be handled are: (1) a thick flexible, external covering or large, flexible bumper guards attached to a rigid bumper-bar which is rigidly attached to the chassis by suitable supports; (2) a rigid reinforced bumper-bar attached to the chassis by means of compliant or compressible impact absorbing devices. While this general approach is used on most 1973 cars, the details of operation of the various systems are markedly different. Whereas, some of the systems utilize fluid-flow through an orifice to absorb energy, Ford Motor Company devices utilize shear deformation of rectangular rubber blocks.

The purpose of this paper is to present information about females and their relationships with machines and to report female reactions to the machine component in the relationship. Since human factors engineering has focused largely on the male operator in the man-machine system, information concerned with female-machine relationships is derived mainly from studies of males. Several studies of females at work and a recent survey examine the role of the contemporary female as a machine user and record her reactions to this role.

The measurement of drivers' performance at the limit of capability is difficult due to methodological problems, moment to moment variability of drivers, differences between drivers, and their interactions with the characteristics of the vehicle, road, and environment. Aspects of longitudinal and lateral vehicle control are discussed by reference to results of braking and steering tests, with emphasis on the variations between the performance of drivers. The effectiveness of drivers in vehicle braking is shown to be a function of the brake system deceleration/pedal force gain. Overall braking performance could also be improved by increasing the abilities of drivers who are poor in this task, by training in brake modulation on dry and wet pavements. The best drivers are as effective as an antilocking brake system, except on the equivalent of ice covered pavement. In steering control drivers increase their response frequency bandwidth as task difficulty increases.

A laboratory test reactor has been used to determine the rates of oxidation of carbon monoxide (CO), hydrocarbons (HCs) as a class, and hydrogen (H2). The feed was supplied from the exhaust of a single-cylinder engine, with additions of H2 and CO in some runs. The test reactor was designed to be well mixed, and this was verified experimentally for mixing on macroscopic and microscopic scales. Wall effects were found to be unimportant. Kinetic data from 157 runs were correlated with global reaction rate expressions containing Arrhenius temperature dependence and power law concentration dependence. CO oxidation was found to be approximately 1/4 order in CO with an activation energy of 28,200 cal/g-mole. HC oxidation was found to be approximately 1/4 order in HC and 1/2 order in each of O2, CO, and NO with an activation energy of 29,800 cal/g-mole. H2 oxidation rates were not well correlated, but a zero-order rate with an activation energy of 52,000 cal/g-mole is reasonable.

Warmup of the Du Pont model V reactor during unchoked engine operation with air injection has been characterized by a nonreactive period, followed by a transition to an ignited condition. The early period is quenched by heat loss. The transition is gradual for hydrocarbons, but more abrupt for carbon monoxide. Model building for the warmup period is directed to the objective of developing a rapid computer simulation to predict light-off times and temperature histories for various reactor designs and operating conditions. Reactor gas temperature and chemical conversions are calculated as solutions for an ideal backmix reactor. Heat balances maintain a record of all reactor metal temperatures for the given configuration. Heat transfer by radiation, convection, and conduction is considered. The presence of a hot spot in the reactor has a strong effect on time to light-off. In addition to lowering the time, such an ignition source shows a great sensitivity to combustible concentration.

Data obtained from six vehicles equipped with current and advanced emission control systems are used to define fuel-exhaust compositional relationships for hydrocarbons and aldehydes, with special emphasis on photochemically reactive exhaust species. The vehicle emission control system is shown to strongly influence hydrocarbon mass emission level and hydrocarbon composition. However, the distribution of individual species within the two reactive hydrocarbon classes, olefins and aromatics, is shown to be only slightly affected by vehicle system. The exhaust olefin data from the current systems are used to define the relationship between exhaust olefin composition and branched character of the fuel paraffin fraction. Branched fuel paraffins are shown to favor propylene and C4 olefin production while straight chain paraffins are shown to favor ethylene production.

The simulation model presented in this report is capable of analytically predicting the dynamic responses of the unibody passenger car during a rear-end barrier impact. A 5 degree-of-freedom system consisting of a rigid barrier mass, four vehicle masses, and seven nonlinear resistances represents the vehicle impacting the barrier, or vice versa. Five equations of motion are derived and ten initial conditions are specified for the model to define an initial-value problem. Due to the complexities of force-deformation characteristics of the resistances, the solution is derived by a numerical method. A computer program in PL/I for the IBM 360/65 is developed to perform the solution. Output data are available in both numeric and graphic forms. The simulation results are in good agreement with the results of the actual barrier test. Examples of application are given to demonstrate the usefulness of the simulation model in investigating various problems of practical interest.

Personal rapid transit (PRT) multimode and scheduled service characteristics of automated people movers are presented. A description of the operating and design features of the single-sided linear induction motor (LIM) and the HOVAIR air-cushion technology is included, along with important characteristics of the vehicle, the guideways, and the switches. The particular advantages of off-line docking stations, such as saving space in stations and improved passenger flow through the use of random access docks, are discussed. The command and control philosophy, some performance data, and rough budgetary price information are also given.

This study describes the effect of spark plug location on NO and HC emissions from a single-cylinder engine with a specially modified combustion chamber. The effects of changes in combustion duration caused either by spark location, dual spark plugs, or charge dilution on NO and HC emissions were also examined. Experiments were run at constant speed, constant load, and mbt spark timing. Nitric oxide emissions were the same with the spark plug located either near the intake or exhaust valve, but were higher with the spark plug midway between the valves or with dual ignition. Hydrocarbon emissions were lowest with the spark plug nearest the exhaust valve and increased with the distance of the spark plug from the exhaust valve. With charge dilution the decrease in NO emission was isolated into a pure dilution effect and a combustion duration effect. The combustion duration effect was minimal at rich mixtures and increased with air-fuel ratio.

A tentative summary has been made of the possible impact of the use of air cushion in the field of passenger ground transportation aboard a guided vehicle, derived from more than fifteen years of research and development including over 1,000 hours of full-scale tests. Basic technical features of air cushion and especially of plenum chambers are recalled with their consequences on guideway and vehicle design, guideway-vehicle interaction and passenger comfort. After giving proper consideration to the speed range in which convenient modes of propulsion can be associated with air cushion suspension to develop a technically feasible system, economical data are proposed. They show clearly the wide areas where air cushion vehicles of the described technology can be used.