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The effects of various combinations of vehicle steering torque gradient, control sensitivity, and lateral acceleration response time on driver-vehicle performance were investigated. Three subjects performed regulation tasks on two facilities (driving simulator and variable response vehicle) under identical disturbance inputs. The performance trends were essentially the same on both facilities, and significant interactions among the three vehicle characteristics were observed.

As evidenced by extensive research work done under contract to the government recently, it is clear that there is a strong federal interest in the limit handling performance of automobiles. Should these efforts come to fruition, manufacturers may be faced with the difficult task of designing vehicles to meet independent and, at times, conflicting handling requirements. Not only must vehicles continue to meet with subjective approval of handling behavior by customers, but they may also be required to meet objective limit performance criteria. Problems arise in that vehicles designed to achieve high levels of limit performance are not guaranteed to be more controllable or subjectively acceptable to customers. This paper shows ways design changes may cause conflicting influences on several measures of performance.

The majority of permanent magnet motors used in today's automobile utilize ceramic magnets in a stereotype design that is a direct descendant of the wound field motor. Designers of these motors should not limit themselves to the self-made rules that dictate the use of high-coercivity, arc-shaped magnets in small airgap geometries. This paper will show that the motor designer can achieve the most optimum, cost effective design for each application only if he gives full consideration to all the ceramic magnet grades and configurations available and matches them to the needs of the application.

Statistics indicate that during the past decade (1967-1976) the number of general aviation aircraft involved in an accident is equivalent to at least 38% of the total U.S. production during that period. Estimates that an aircraft will be involved in an accident over a 20 year life range are as high as 60-70%. Recognition of this probability has led to crashworthiness and occupant survivability “packaging” design concepts as offering the most realistic approach to reduction of serious and fatal injuries when an accident occurs. This paper reviews and illustrates current general aviation aircraft accident experience relative to occupant impact injury and damage indexes, and provides new data relative to current-generation aircraft.

The best COBALT magnets are of SmCo5 type made by the powdered metallurgy-sintering process and provide energy products up to 160 kJ m3 (20 MGOe). Up to 90% of the samarium in SmCo5 can be replaced by more plentiful rare earths, to produce magnets with energy products approximately 70% that of SmCo5. This versatility allows motors to be optimized with respect to the availability of the various rare earths and the motor requirements. Bonded magnets are less brittle and can be machined but the magnetic properties and thermal stability are inferior to sintered magnets. Magnets can be laminated to powdered iron for improved toughness. COBALT magnets are available in small amounts from 22 magnet manufacturers and the starting material powders are produced by seven processors.

Permanent magnets are playing an increasing role in automotive applications. They are potential energy storage devices which can be effectively used in accessory motors, sensing systems and actuators, sometimes in combination with micro processors, to conserve energy, save weight, reduce pollution and to increase safety. This paper will discuss commercial magnet materials available and some of the many applications using these materials.

Ethyl has been conducting extensive emission studies of two car fleets to investigate any effect of MMT on exhaust emissions from production cars. One fleet is being operated by Ethyl for 50,000 miles on an EPA-type durability route. This fleet consists of thirty 1977 California cars - six cars each of five models (four U.S. and one import). Two of each model are using clear certification fuel, with two each using the certification fuel plus 1/32 g Mn/gallon or 1/16 g Mn/gallon. Although the test is still running, the 16 U.S. cars using clear fuel or 1/16 g Mn/gallon have completed the 50,000 miles. For these cars, the average increase in HC, CO, and NOx emissions was essentially the same for both the clear-fuel cars and the MMT cars, with deterioration rates being somewhat lower for the MMT cars. The second test involves 20 cars from a large oil company fleet of 1975 and 1976 catalyst-equipped cars used by salesmen in the field.

The effects of using the manganese fuel additive, MMT, on experimental engine emission control systems have been evaluated in a prototype vehicle test program. Two types of engines and catalytic converters were used in vehicle emission control systems designed for compliance with the .41 HC, 3.4 CO, and 2.0 NOx g/mi standard. Testing included multiple engine dynamometer and vehicle schedules which accrued the equivalent of nearly 2-1/2 million vehicle miles. The only major adverse effect of MMT fuel usage observed was a twofold increase in engine and tail pipe hydrocarbon emissions over the 50,000-mile vehicle test schedule durations employed. This increase was attributed to a build up of manganese oxide deposits in the engine combustion chambers.

Monolithic oxidation converters can become plugged with manganese oxide deposits when the gasoline contains the antiknock additive MMT. Engine dynamometer studies showed that the rate of converter plugging depended on the catalyst inlet temperature and the concentration of MMT in the fuel. Converter plugging was not affected by base fuel or engine oil composition, and it occurred as readily with a bare monolithic support containing no catalytic material as with a production catalyst. Monolithic converter plugging appears to be a physical, rather than a chemical phenomenon, in which the manganese oxide collects primarily on the inlet edge of the converter.

This paper reviews the elements necessary to design and develop integrated air conditioning and heating systems for trucks. Included is discussion of the pertinent sub-systems: dash mounted air handling components, air distribution system, operator controls, refrigeration circuit, electrical system and vacuum system. Also reviewed are the physiological factor involved in heating and air conditioning.

A new combustion system - called MCA-JET- has been developed to improve combustion under the low speed, low load conditions typical of urban driving. Engines with this new system incorporate a special “jet valve”, in addition to the inlet and exhaust valves of the conventional combustion chamber, which directs air or a super-lean mixture towards the spark plug, and induces a strong swirling flow in the cylinder. This swirl persists during the compression and expansion processes, moves the mixture spirally and helps the flame to propagate. As a result, the combustion of lean mixtures, including those with exhaust gas recirculation, can be carried out rapidly and thus the fuel economy improved.

Effects of gas mean residence time and residence time distribution on the emissions performance of automotive thermal reactors were evaluated using a research reactor which provided independent control of volume, internal configuration, and heat loss. Steady-state tests of this reactor on a lean-mixture, multicylinder engine revealed that mean residence time significantly influences the performance of well-insulated reactors. However, high heat loss diminishes the residence time effect in uninsulated reactors. Adjusting reactor configuration to improve residence time distribution increases performance irrespective of heat loss. Overall, insulated “2-pass” reactors are nearly optimum.

DURING ENGINE DYNO durability testing of oxidation catalysts, manganese deposition on the catalyst hot faces sufficient to affect catalyst performance for HC and CO conversions was observed. The severity of the problem is related to the MMT level in the fuel, the cell density of the catalyst's monolithic support, and engine aging time. The nature of manganese deposition in these studies and how it affects catalyst performance is explored. Apart from the MMT phenomenon, comparative studies of oxidation catalysts on conventional ceramic and high cell density, thin-wall metallic supports indicate that the latter offer significantly improved HC conversion durability.

The antenna test engineer, by defining his basic needs and utilizing relatively uncomplicated measurement techniques, can easily define the performance of most vehicle antenna designs. Employing basic “off-the-shelf” instruments and an uncomplicated test site approach, the cost of the test range can be minimized while retaining maximum versatility. Due to the phenomenal growth and interest in Citizens Band (CB), measurement techniques for CB will be emphasized along with AM and FM bands.

A new 40-channel CB Radio System has been developed by a major automotive manufacturer as a regular production option for a number of its 1978 cars and trucks. To maximize theft resistance, the system uses a remote chassis, detachable microphone, and a tri-band antenna. The factory-installed CB features a uniquely styled power microphone, digital channel display, automatic scan, switchable noise blanker, memory for emergency channel 9, automatic noise limiter, and extensive vehicle noise suppression. Vehicle speaker(s) are time-shared with the entertainment system. This state-of-the-art system is presented here in terms of component functions, design development, manufacture, and test equipment and procedures.

This paper discusses the relative effects of transmitter power, antenna efficiency, and interference from local and distant stations on the communicating range of a mobile CB station. Performance comparisons between several popular antenna types and curves of signal strength versus distance are included.

Application of dedicated microprocessor controlled and frequency synthesized AM-FM electronic tuning with digital display and unique push button keyboard control in an automotive radio. Presentation of the human engineering, technical aspects and benefits of an all electronic approach. Description of the modular design of the finished radio and application of computerized testing.

Electronic tuning and frequency synthesis techniques have made possible the combination of an eight-track tape player, digital clock and AM/FM/Stereo/Signal-Seeking automobile radio in a 2700 cm3 package. Phase-locked-loop circuitry, varactor tuning, and calculator logic replace the conventional mechanical tuner and provide all its functions. In addition to reducing receiver weight, this tuning technique assures extreme tuning accuracy and frequency stability.

The use of electronic digital tuning in automobile radios offers many advantages. These include radios of reduced size and weight which are becoming all important considerations in the design of all automotive components. In addition, the reduced size allows considerable freedom for interior stylists. At the same time, electronically tuned radios offer superior performance at reduced cost. This paper demonstrates the probability that in the near future nearly all automobile radios will be digitally tuned. It provides a direct comparison between presently available radios and all-electronic radios.

A study has been made of the influence of press forming and corrosion under cars on the fatigue properties of sheet steels. Press forming was done in the laboratory and corresponded to types of deformation occurring in production. Samples from laboratory and undervehicle corrosion environments were tested. Forming was found to improve fatigue properties and corrosion to cause a deterioration. The drop in fatigue strength caused by corrosion was similar for all types of steel examined, and no worse than that caused by moderate notches that are commonly encountered in service.