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As the evidence of the contribution of intoxicated drivers to vehicular fatalities continues to mount, interest has grown in the development of novel counter-measures. One approach now being considered involves the use of a device installed in the automobile which automatically determines if the driver is intoxicated and prevents the driver from operating the vehicle when intoxication is determined. In this paper such devices are discussed with particular consideration given to the method of determining intoxication, the point in time when the determination is made and their applications. The paper also discusses the Transportation Systems Center's research program directed to dealing with this problem.

This paper is an expansion of a previously presented paper “Ignition Interlocks for Intoxicated Drivers,” with additional data analysis which exposed the basic problems resulting from the operation of automobiles by intoxicated drivers in the United States. Several approaches to the development of ignition interlock systems are discussed. The Phystester,* an ignition interlock developed by General Motors and based on a predriving performance test of short duration, is discussed. Plans for evaluation of its effectiveness are presented, and available data from experiments involving both sober and intoxicated subjects are included. Integration of the Phystester in the operation of the vehicle and additional functional uses of the device are also discussed. Results of the Michigan Breath Testing Program, 1970-1971, are provided as an Appendix.

One of the effects of the existing and proposed European legislation limiting vehicle noise has been to generate a requirement for quieter engines. A simple analysis of the vibration of the external surfaces of several in-line engine structures has shown how the noise from the engine surfaces can be reduced, provided that all the thin-section areas of the external surface are treated. Noise-reduction techniques have been evolved for all the commonly used surface structures for diesel engines, and these are described in this paper. Four in-line diesel engines have been treated by these techniques, and noise reductions of 5-8 dBA have been obtained. In all cases, the same manufacturing plant was used to machine the modified crankcase/cylinder block casting; the valve gear cover and sump were modified versions of those already fitted to the engine.

An evaluation of gaseous fuels was made to determine their capability in reducing emissions from automobiles. The four-part program included tests of propane (LPG) and natural gas in a dynamometer engine (phase one) and in a car parameter study (phase two). Power and spark requirements were compared with those of gasoline on the dynamometer engines. Emissions, economy, performance, and drivability were evaluated on the cars; and air-fuel ratio, spark advance, and exhaust gas recirculation served as variable parameters. The third phase of the program determined the low-emission capability of an LPG car with proposed emission hardware. The economy, performance, and drivability at these low levels were obtained. The final phase tested a dual-fuel car to evaluate the feasibility of using LPG to start and warm up the car, followed by an automatic switch to gasoline. The emissions, drivability, and the LPG fuel consumption were recorded.

A program was conducted to determine the effect of temperature and humidity on exhaust emissions from automotive engines. The objective was to determine if the effects were of sufficient magnitude to require the application of correction factors to measured exhaust emissions to standard humidity and temperature values. Both American and foreign-made vehicles were tested at 20 combinations of ambient temperature and humidity. The effect of temperature and humidity was found to be both unpredictable and of little significance for hydrocarbon and carbon monoxide emissions. No correction factors were developed for these exhaust gas constituents. The effect of temperature was found to be of little significance for oxides of nitrogen. However, humidity effects were found to be significant and predictable for oxides of nitrogen.

Published test results have established that the recirculation of a portion of an engine's exhaust gas is an effective means of reducing oxides of nitrogen in the exhaust. Many methods of flow control have been tried; some require extensive revisions to the carburetion system. A retrofit system in which recirculation and spark advance are selectively controlled by vehicle speed and vacuum level has been tested on various cars to give 30-70% reductions in NOx as well as significant reductions in HC and CO. Revisions to the existing power train are minimal, while changes in driveability and fuel economy are hardly noticeable.

Reactions of sulfur, present in small amounts in gasoline, with catalyst and catalyst support materials are discussed. GMR studies have shown that sulfur accumulates in catalysts and support materials at temperatures of 600-1300 F under both oxidizing and reducing conditions. Partial sulfur release has been observed at 1200-1600 F. Concurrent with sulfur accumulation, there is a marked reduction in the carbon monoxide (CO) reactivity of noble metal, promoted and base metal catalysts. Lesser highly variable effects on hydrocarbon (HC) reactivity were noted. Studies of nitrogen oxide (NOx) reducing, noble metal catalysts also showed an adverse effect of sulfur accumulation on the NOx reactivity. These results indicate that steps must be taken to reduce or eliminate sulfur poisoning of automotive emission control systems. Approaches for achieving this objective are discussed.

This paper shows that the rise in engine temperatures of automobiles has created a need for elastomers which can resist the deleterious effects of the higher heat. In addition to the high temperature requirement, a material with high tear and high modulus was also needed, as it is anticipated that there will be an increased use of silicone rubber fabricated parts. It is also pointed out that silicones have continued to improve their physical properties so that they are now being used in many automotive applications, and will be the answer to many design problems confronting the industry today. It is further predicted that there will be a need of silicone rubber adhesive/sealants to replace preformed gaskets and as bonding agents for trim and automotive ornaments.

The high-temperature properties of silicone rubber are compared to those of six organic rubbers. New data on properties at temperature, as distinct from standard heat aging data, are presented to guide the designer and materials engineer. The properties of fluorosilicone rubber are also discussed. Current automotive applications of both silicone rubber and fluorosilicone rubber are described.

This paper describes the implementation of Title 2 of the Clean Air Act, with special emphasis on the emission standards and test procedures which will apply to 1975 and 1976 light-duty vehicles. Discussed are the new test procedure to measure an average car's emissions, and the EPA's tests and analysis-particularly the baseline study of emissions from 1971 cars-which became the basis for setting the new standards. The complex control systems being designed to meet the 1975 standards are expected to require more maintenance attention than the control systems currently in use. The EPA expects to allow more maintenance on durability vehicles than is allowed by the currently-applicable regulations, but will condition its approval of more maintenance on its reasonableness; reasonableness is discussed.

The CO2 tracer technique is a method of measuring automotive exhaust mass emissions during arbitrary modes of operation of a car on the 1972 federal emission test driving schedule. This technique allows modal mass measurements of low-emission cars based on undiluted exhaust gas concentrations. The CO2 concentration at the tailpipe is compared with the CO2 in the diluted stream to obtain exhaust flow. This flow, multiplied by tailpipe concentrations of hydrocarbon, carbon monoxide, and nitric oxide, and integrated over the driving mode, gives modal mass emissions. Problems associated with the lag between the time at which a transient maneuver takes place in the engine and the time at which measurements are recorded are also discussed.

The problems encountered in mounting fire pumps, fire truck bodies, and related equipment on chassis are discussed. The problem area is defined and recommendations are offered for each of the following areas of the chassis: frame, electrical systems, fuel systems, brake systems, transmission and PTO systems, exhaust systems, drivelines, and lights. More technical cooperation between body builders and chassis manufacturers is suggested.

The formed-in-place gasket concept consists of using a paste-type liquid silicone RTV (room temperature vulcanizing rubber) applied to the flange area of the components to be sealed and having the flanges squeeze out and form the liquid gasket on assembly. This system offers several advantages over the conventional precut or preformed gaskets. This system can replace all the static gaskets on a drive train (except head and manifold) and perform as well or better than the gaskets it replaces. Material cost can be reduced as can handling costs when the RTV is automatically applied.

Miniaturization of terminals, connectors, springs, and other contacts in automotive electric systems has imposed rigorous demands upon the principal materials used in their manufacture-copper alloys. This paper surveys the more important copper alloys and presents available data, including that from current research, which bear upon the problem of material selection. Various coppers, copper alloys, and groups of copper alloys are described, and a brief description of mechanical and electrical properties, corrosion performance, surface characteristics, and economics is presented. Comparative data for the various representative copper alloy groups are also presented. Such data includes comparison of mechanical strength-ultimate tensile, offset yield, and fatigue strengths, modulus of elasticity; corrosion resistance-general, stress, and crevice corrosion, dezincification; and surface characteristics-contact resistance, solderability, plating performance.

Adjustment and inspection of headlamp aim may be accomplished by four methods: visual, optical, photoelectric, and mechanical. Visual aim is the simplest but the least accurate. Lateral accuracy is restricted by the ability of the driver to align the vehicle perpendicular to the aiming board and the difficulty of determining the edge of the high-intensity zone of the low-beam lamps. The precision of visual aim is considerably less than the tolerances prescribed in the SAE J599b, Lighting Inspection Code. An optical aimer projects a reduced image of the headlamp beam on a screen. Difficulty in visually determining the edge of the high-intensity zone of the low-beam lamps and inability to accurately align the aimer to the vehicle results in inaccurate measurement of headlamp aim. Two photoelectric aim systems are available.

Automatic transmission clutch failures and rapid oxidation of the transmission fluid have sometimes been attributed to high temperatures in the clutch pack. For the purpose of estimating these temperatures, an analysis was made of the clutch system, and a solution was developed from the partial differential equations of heat conduction with appropriate boundary conditions. The solution thus obtained was verified experimentally. There were several important conclusions to this study. The maximum temperature rise occurs somewhat earlier than the end of the lockup time. The interface temperature rise increases as the lockup time decreases for a fixed amount of energy input. The ratio of heat flux entering the reaction plate to that entering the composite plate is not constant, as has been assumed by others. The heat absorbed by the fluid outside the clutch pack is negligible during the short lockup time. Temperature rises for some typical cases are computed.

The development of the AUTO TEMP II Temperature Control System used in Chrysler Corp. vehicles is summarized. A description of the design, development, function, and manufacturing aspects of the control system is presented, with emphasis on unique control parameters, reliability, serviceability, and check-out of production assemblies. Auto Temp II was developed by Chrysler in conjunction with Ranco Incorporated. The servo-controlled, closed-loop system, which has a sensitivity of 0.5 F, utilizes a water-flow control valve for temperature control, along with a cold engine lockout. The basic components are: sensor string, servo, and amplifier. All automatic functions involving control of mass flow rate, temperature, and distribution of the air entering the vehicle, are encompassed in one control unit. All components are mechanically linked through the gear train and are responsive to the amplifier through the feedback potentiometer.

In an earlier paper, a series of comparison tests were described that verified the cost/performance advantage of die-cast zinc over five unreinforced, engineering thermoplastics in tension, flexure, creep, impact, and fatigue when compared under identical test procedures and specimen geometries as dictated by plastics industry standards. Additional tests showed the superiority of die-cast zinc over these same thermoplastics in regard to thread strength, dimensional stability, heat distortion, weathering, flammability, and chemical stress cracking. This paper reports on a continuation of these same series of test procedures where die-cast zinc is compared with six 40% glass-reinforced thermoplastics. Again the results continue to show the cost/performance superiority of die-cast zinc over the reinforced thermoplastics tested.

A digital memory fuel control unit has been developed for otto cycle engines which enables low pollution exhaust emissions to be achieved, coupled with good drivability and mechanical performance. The unit has been tested on a Triumph 2.5 PI vehicle, and the practical results achieved fall just short of the requirements of the 1975 federal and California legislation. The electronic controller receives signals relating to the engine's instantaneous operating conditions and, by reference to its digital memory, computes the optimum fuel required. The capacity of the controller's memory is effectively increased by an interpolation technique. The controller operates as an on-line process control computer, of cigar box dimensions, which is able to exist in the arduous automotive environment.

A digital computerized energy distribution and automated control system is being developed at Essex International's Vehicular Research and MOS Manufacturing Facilities in Pittsburgh. The control system is comprised of a central computer in conjunction with a digital multiplexing system. Prototypes of the system have been tested; the subsystems of the car that were tested include fuel injection, ignition, power assist, comfort, and lighting. In its final form this system will make decisions for all the subsystems on the automobile. For example, antiskid braking, gear selection, automatic speed control, and driver displays will be incorporated. The system will evolve onto the car in pieces such as engine control, lighting, and automatic temperature control. Then, as economic factors dictate, the components will evolve into a single computerized system. The automatic temperature control system is economical today. The central computer will be economical for certain functions in 2-3 years.