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An instrument has been developed for obtaining fuel antiknock ratings in cars by the Modified Borderline, the Modified Uniontown, or the E-15 Octane Number Requirement Technique. It gives ratings that are more precise than those obtained conventionally, and the raters need not be so highly skilled. When combined with an automated driver, data logger, and fueling system, it permits up to 64 fuels to be road rated in triplicate at both full and part throttle by a single operator in an 8 h shift. Reproducibility is about 0.7 octane for full throttle and 0.9 for part throttle, compared with about 1 and 1.5 octane, respectively, for conventional ratings.

The United States total transportation energy consumption represents 25% of our domestic consumption and 55% of our petroleum consumption, and it is expected to continue in these proportions in the foreseeable future. We currently have a petroleum import requirement that is projected to increase by the mid-1980s to 50% of the total petroleum consumption, comparable to the projected total transportation energy consumption at that time. The paper discusses the current structure of our transportation services and energy consumption, with particular emphasis on the public transit modes: bus, taxi, rapid transit, trolley, and commuter rail. Data are drawn from various sources and integrated to form an overall view of urban transit impact on energy consumption. Several option examples for conserving public and private transit energy are identified and evaluated for comparison purposes. Comments are included regarding other impacts concerning the optional examples selected.

Viscosities at high and low shear rates were measured both before and after mechanical shear for the 12 ARO multigrade engine oils of the ASTM D 2, R & D VII-B Mechanical Shear Stability Program. The oils were divided into two groups by ?Nsp, the difference between low shear rate specific viscosity at 98.9 and 37.8°C (210 and 100°F). The positive ΔNsp group suffered the greater average low shear rate permanent viscosity loss. Permanent viscosity loss at high shear rateswhere most machine operation occurs-was significantly less than at low shear rates for both groups. In several cases, the low shear rate permanent viscosity loss was nearly equal to the new oil temporary viscosity loss. Several of these oils became nearly Newtonian after mechanical shear. Long-term storage produced measurable viscosity recovery in some sheared oils. These observations are consistent with the hypothesis that polymer entanglements exist in conventional multigrade oils.

A generalized approach is taken looking at automobile emissions and energy problems from the vantagepoint of a state government regulatory agency. The auto industry's vast capability for technology, mass production, quality control, and marketing ability culminates at the dealership. Thereafter, the vehicle is often viewed by the user much differently. Initially, this paper attempts to overlay many of the different disciplines that formulate the final product. By examining a wide range of environmental ills, in part created by the automobile, and by analyzing how the automotive industry has adapted to past crises, the impending emission and energy questions are explored by using various economic, regulatory, and engine design trend indicators. Prospectives for analyzing these problems are demonstrated.

Test series were run on subjects in a motor vehicle simulator and in actual motor vehicles. The test objective was to study the correlations among the subjective evaluation of vehicle handling qualities, test measurements, and various characteristics. Although the data presented in this paper should be considered only a first step, the comparison of simulator results with road test results yielded good data correlation. It was found in both cases that the vehicle response rate (for example, yaw angle velocity) on a sudden steering angle step input exerts much greater influence on the judgment and the performance of the test subject than does, for instance, vehicle damping.

An open-loop limit-maneuver test methodology was refined from an earlier study which hypothesized a relationship between vehicle performance and highway safety. Refinements in methodology were attained in the areas of test apparatus, test procedure, data processing, and performance interpretation. Open-loop response measurements were conducted on a representative sample of 12 contemporary passenger vehicles. Numeric characterizations of performance are presented, indicating the range and distribution of response properties exhibited by the vehicle sample.

This paper describes a 14 degrees-of-freedom mathematical model that was developed to analyze and predict the handling dynamics of a 4-wheel vehicle. The system of nonlinear equations was programmed and numerically solved on the digital computer where the inputs are Ackerman steer angle to front and/or rear wheels and driving or braking torques on any or all wheels. The equations of motion for the sprung and unsprung masses were derived using Lagrange's equation. Constraints were included in the equations, which forced the sprung mass to roll about an inclined center roll axis. The analysis also included nonlinear tire characteristics as well as suspension geometry and compliance parameters, such as roll steer, roll camber, auxiliary roll stiffness, and lateral force deflection steer. The results of computer simulations for J-turn maneuvers are compared with experimentally measured data for two different speeds and steering inputs.

To lower emissions from a multicylinder engine, the air-fuel ratio must be optimized in all cylinders. If uniform fuel distribution is achieved, then the cylinder-to-cylinder air distribution is of particular interest. A probe system has been developed to measure mass flow rates to individual cylinders during operation of a complete engine. Fast response measurements of pressure, temperature, and flow velocity are made in the intake port near the valve during the intake portion of the cycle. High-speed collection of the large volume of data was accomplished through on-line use of an IBM 1800 computer. A V8 455 CID (7457 cm3) engine with stock intake and single exhaust system was used in the initial application of the mass flow probe. Measurements of 30-40 individual cycles were combined to calculate the mean volumetric efficiency for each cylinder.

The metallurgical possibilities for increasing the strength of cold-rolled sheet are briefly reviewed. Solid solution hardening, precipitation hardening, grain refinement, and dislocation substructure can be used to varying extents to strengthen partially or fully recrystallized sheets. Yield strengths ranging 45-100 ksi (310-690 MPa) and higher appear to be technically feasible, and steels with yield strengths up to 65 ksi (450 MPa) are close to commercial production. The average plastic strain ratios of the high-strength cold-rolled steels are somewhat higher (1.0-1.35) than for similar hot-rolled steels but still relatively poor when compared to low-strength aluminum killed deep drawing sheet.

The dent resistance of cold-rolled low-carbon steel sheets is shown to be proportional to the product of the yield strength and the square of the thickness. However, the yield-strength value used in this relation must be the yield strength appropriate to the strain rate of the particular indentation process. The use of a yield-strength value obtained in a slow-speed tension test, for example, can lead to an erroneous estimate of the dent resistance of a sheet for an indentation process in which the strain rate is many orders of magnitude higher, as is usually true in commercial denting situations.

Secondary air scheduling and average delivery rate have a great influence on the performance (carbon monoxide and hydrocarbon cleanup) of rich thermal manifold reactors. A continuously modulated secondary air system was devised to provide a tailpipe air-fuel ratio that did not change significantly with engine speed or load when a “flat” carburetion calibration was incorporated. This system involved throttling the inlet of the air pump(s) so that the air pump and engine intake pressures were equal. The continuous air modulation system was compared with an unmodulated system and a step-modulated system. The secondary air systems were investigated with both GMR “small volume” cast iron thermal reactors and Du Pont V thermal reactors on modified 350 CID V-8 engines in 1969 Chevrolet passenger vehicles. It was found that thermal reactor performance improved with each increase in control of the secondary air schedule.

An exhaust emissions laboratory has been established where soak-and-test investigations can be performed in an integrated, climate-controlled setting, in accordance with the 1975 Federal Test Procedure. Catalytic converter designs, catalyst materials, and other emissions-related engine and vehicle components are tested in this laboratory. The paper discusses the new facility's capacity for making converter modal efficiency measurements, and it provides details on the real-time data processing, as well as on the improved controls of test variability. The laboratory layout is described and illustrated, and information is furnished on data acquisition and reduction, facility calibration, and experience with a servo driver and with materials evaluation vehicles. Both an analog computer and a minicomputer are used in the laboratory, and the printout copy reproduced here includes a real-time modal data sheet, a test summary, and a data repeatability analysis.

This paper is concerned with the forecasting of the tire industry, as seen by a supplier, with special emphasis on the possible future of steel as a reinforcement material and on some of the forces which may affect steel usage in the next decade. In making its forecasts of future reinforcement needs, Monsanto placed primary emphasis on projecting market shares by tire construction type: bias, bias belted, or radial, and on the reinforcement material of choice in each market segment. Current trends and forces shaping the future of the tire industry are analyzed, and graphs are presented of automotive production and a variety of tire projections from 1972-1982.

An electronic servo controller, combined with an electric chassis dynamometer and a synchronized mini-computer generated command signal, provides consistent and smooth driving of development vehicles on EPA emission runs. The electronic controller provides the necessary signals to actuate the throttle servo to power the engine, and to generate braking torque on the chassis rolls of the electric dynamometer. The servo gain and compensation circuits allow accurate and stable operation over a wide range of engine loads, transmission gear ratios, and car speeds. A single gain-compensation network is sufficient for vehicles used in AC's catalytic converter development program. Safety shutdown circuits and ease of installation are provided in the design.

A comprehensive EPA emission test analysis program has been developed to determine the nature and relative significance of test variability and to provide consistent evaluation of the performance of catalytic converters. This includes real-time recordings of emission concentrations and mass rates, catalytic converter efficiencies, and air-fuel ratio. Mass accumulations are printed out during the test at the end of each test mode. Test results and analysis of repeatability are summarized on-site immediately following the test. Simplified relationships between gas concentrations and engines variables have been developed.

A three-point program is described which provides overall control of vehicle emission testing and assurance of acceptable product design. 1. Experimental design techniques are used in the test development activities to control test parameters and to insure sufficient test repeatability for test evaluation. 2. Test histories, established and automatically maintained on computer files, are continuously monitored to assure test control and to provide insights into the effects of various test parameters. 3. The objectives of each specific test request are analyzed and experimental designs utilized to develop test plans and procedures. Illustrative examples in each area are included.

Piezoresistive phenomena found in silicon semiconductors and the possibility it has of integrating various electronic functions (all in one family of technology) are a viable method of meeting the future requirements of the automotive industry. After a brief discussion of the evolution of semiconductor sensors and the “state of art” design, the author proceeds to propose some suitable circuits for integration of electronic functions such as comparator, amplifier, A to D converter, etc. Although the discussion centers on pressure transducer design, the facts in the example can easily be transferred to temperature, flow, and acceleration measurements.

Hydraulic power braking systems for use in passenger cars and light trucks are attracting considerable automotive design attention. This is due to their compactness, smaller space requirements, and better operating “feel,” as well as their more direct control over the braking function, which has extremely short application and release times. Moreover, they are readily adaptable to the energy source and controls of an antilock system, and they contribute to (or even form the basis of) a central power-supply system that would provide servo assistance to other vehicle systems. This paper describes and explains ways of creating these brake systems and gives design calculations of brake layouts based on standard values and comparative judgment criteria.

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.

Unlike lithium chloride, chemical, and other surface-type elements, the Brady Array exhibits bulk effects conforming to the Poole-Frenkel law concerning bulk phenomena. Other types of sensors require agglomeration of water or moisture prior to measurement; in the array, measurements are accomplished at a discrete molecular level, resulting in extremely rapid response and recovery times (better than 150 ms). Stressed bonds within the structure initiate rapid recovery by purging the sensor when it is moved from higher to lower values of relative humidity. The sensing element is contained within a TO-5 type transistor housing, measuring only 10 mil in diameter and 100 mil in length. The array has been operated over temperature extremes ranging - 200 to +800°F without damage or loss of calibration. The technique employed in the array also lends itself to sensing of other gases, when constructed using techniques proprietary to Thunder Scientific Corp.