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This paper reviews some of the progress that has been made in recent years in the transportation field by behavioral scientists and human factors engineers. The major areas covered are public transportation systems, railroad systems, highway systems, and personal transportation systems. The report suggests what future problems may be encountered in these areas that will need the attention of human factors specialists.

A study was undertaken to describe the effects of various annealing treatments, both intercritical and supercritical, on the mechanical properties and microstructures of six dual-phase, Mn-Si, Mn-Si-Cr, Mn-Si-Mo and Mn-Si-V steels having nearly equal hardenability. It has been found that the combination of tensile strength and total elongation after intercritical treatments may be slightly better than that after supercritical treatments. Although hardenabilities of these six alloys were more or less equal, it appears that the strength-ductility relationship varies a little (though not very significantly) with chemistry. The strength-ductility behavior of Mn-Si-Cr steels compares quite favorably with that of commercial Mn-Si-V steels with optimum processing conditions for both. It has been confirmed that the tensile strength of dual-phase steels is primarily a function of the hard-phase (mainly martensite and bainite, if any) content at a given ferrite grain size.

Stiffness and vibration frequency of automotive structures are shown to be dependent upon an effective modulus. Under typical loading conditions the effective modulus would be much less than the elastic modulus. The concept of the effective modulus ratio is introduced as a dimensionless quantity to describe the change in apparent modulus. It is shown that HSLA steels, specifically HI-FORM 50 and HI-FORM 80, are less affected than AISI 1005 steel.

The increased usage of high-strength, cold-rolled steels has revealed differences in spot welding characteristics between the thin, high strength steels and the plain carbon steels commonly used in the automotive industries. The response of four, 275 MPa yield strength, cold-rolled steels to a variety of spot welding schedules was determined through an evaluation of mechanical property and fracture appearance tests. The results of this study were compared to various weld quality evaluation criteria and suggestions for a revised criteria were proposed.

The spot welding characteristics of VAN-QN (80), a dual-phase HSLA steel, were examined with regard to the strength and ductility of spot welds under static, impact and cyclic loading and compared to a conventional V-N HSLA steel and SAE 1008 low carbon steel. The maximum tensile shear strength of VAN-QN (80) spot welds was found to be proportional to the thickness and ultimate tensile strength of the base metal. VAN-QN (80) spot welds, therefore, were only slightly lower in strength than those in a conventional 80 Ksi yield strength HSLA steel but up to twice the strength of welds in low carbon steel. Weld ductility was lower for VAN-QN (80) than for low carbon steel but greater than for conventional HSLA steel and increased with material thickness. The impact and fatigue properties of VAN-QN (80) welds were similar to those in conventional HSLA and low carbon steels.

Microstructure, mechanical properties, lab formability and ageing response of two as-hot-rolled dual phase steels, a heat treated dual phase steel, and microalloyed 345 MPa and 550 MPa (50 ksi and 80 ksi) steels are compared. Measurements and implications on press performance of: work hardening behaviour, strain rate sensitivity, elongation before necking, resistance to edge cracking, and uniformity of properties are discussed. Formability of both heat treated and as-hot-rolled dual phase steels was found to be similar at a common strength level, their formability lying between that of the 345 MPa and 550 MPa steels.

A new three-speed automatic transmission has been designed, developed and is being produced in the U.S. by the Chrysler Corporation for its new family of front wheel drive vehicles. The transmission was designed around the Chrysler-proven TorqueFlite concept. The features of the new transmission include a “folded” construction for installation in a transverse power train. The case is a one-piece aluminum die cast housing and contains the final drive and differential unit. This paper describes the design and development of this new automatic transmission.

The extent of automatic transmission fluid oxidation is compared for short term bench transmission tests with long term vehicle tests. The technique of Blotter Spot Analysis is emphasized for the comparison. Blotter Spot Analyses can help decide when an automatic transmission fluid should be changed in severe service.

The over-riding social importance of automotive fuel economy and power plant exhaust emissions is discussed in relation to proposed alternatives to the spark-ignition passenger car engine. Some engineering and use criteria for the selection of alternatives are proposed, and several alternative power plants are explored in their frame work. Three gas turbine types are discussed as alternatives, and a brief history of two-shaft turbines is presented. The influence of various automatic transmissions on passenger-car fuel economy and driveability is summarized. This paper concludes that automatic, continuously variable transmission functions can be achieved with a three-shaft turbine power plant with excellent fuel economy and at lower cost.

The scope of the hybrid propulsion systems studies that have been developed by FIAT Research Centre, is the energy consumption evaluation in comparison with conventional traction drives. After a general study on the hybrid propulsion systems, mathematical models have been developed for the evaluation of performances and energy balance. The construction of a prototype with parallel hybrid propulsion system has been completed to validate the computer simulation models. Computer and on road tests results are reported. Criteria used to select the parameters to the optimization of the system are discussed.

An automatic transmission fluid has been developed which can meet the needs of transmissions designed for either friction modified or non-friction modified fluids. Approved under the DEXR0N*-II and M2C138-CJ specifications, it also meets all the requirements of the M2C33-F (Type F) specification except for the friction modifier content. Since use of a friction modified fluid in Type F applications would represent a radical departure from current recommended practice, data, both pro and con, on the concept are presented.

This computor simulation analysis has been tried as an efficiency study using the Daihatsu Engine/Electric Hybrid 1.5 ton truck which has the “DHS” systems, and run in accordance with three driving patterns such as U.S. LA-4, Australian eight and Japanese ten modes. Every input data are measured and/or evaluated through the actual test and, for the selection of the four driving modes the “DHS” has, three cases of specific fuel consumptions of 190,200 and 210 gr/PS gr/PS · h contour lines are used. As results, the accurate differences of the fuel consumption has been found under every cases.

The determination of the total antioxidant capacity of new and used automatic transmission fluids can yield information useful in the study of fluid stability, severity of service and correlation between bench tests and service. The technique is particularly useful in the characterization of the earlier stages of fluid oxidation where parameters such as T.A.N., pentane insolubles and viscosity yield little information. Three fluids from a fleet test manifested different antioxidant decay profiles. Data obtained from a laboratory beaker test indicate that some test conditions can reproduce these decay curves and thus simulate the primary oxidation processes occurring in the transmission in this fleet.

A method is presented for optimizing the engine/secondary usage strategy of a hybrid vehicle. A powertrain simulation is combined with dynamic programming techniques for calibration optimization, and a sequential decision algorithm for specifying optimal operating points for both engine and secondary drive systems. An overview of road-load matching and strategy requirements is presented.

The following paper has been prepared to describe the procedures used by the Vought Corporation to fabricate automotive body components in graphite reinforced plastic for the Ford Motor Company Graphite 1979 Ford LTD. This effort was a joint venture by the Milford Fabricating Company - a subsidiary of the Budd Company - and the Vought Corporation. Graphite Fiber Reinforced Plastic, the specified material for the major body components made it necessary to unite proven aerospace methods with current automotive prototype technology to ensure successful completion of the project. Areas to be discussed will be the master tooling aid development, high temperature epoxy molds, and component fabrication.

An experimental LTD chassis frame, for a 1979 Ford experimental vehicle, was designed and fabricated in graphite-reinforced plastic. Prototype composite moldingtechniques were employed to form the closed frame sections required for strength and stiffness. Weight savings were realized because of both component integration and material substitution: compared with its steel counterpart, the graphite frame afforded a 79 pound weight reduction while providing a 33% increase in torsional stiffness and a 16% increase in bending stiffness. The frame passed laboratory suspension and steering load tests and has been incorporated in the experimental vehicle, but not vehicle tested.

A new as-hot-rolled HSLA steel has been developed for application as round and flat bars. This material possesses a minimum yield strength of 80 ksi coupled with good bendability, weldability, and fatigue performance. This material offers design engineers and manufacturers the flexibility to upgrade from lower-strength materials to (a) increase load carrying capability of their present structures or, (b) realize important weight and energy savings by going to lighter section sizes at present load ratings. It also enables them to take advantage of its high strength to replace more costly heat treated grades.

The following paper has been prepared to describe the procedures used to fabricate and assemble a lightweight demonstration vehicle, built under contract to Ford Motor Company. G.F.R.P. (Graphite Fiber Reinforced Plastic), the specified material for the major body components, made it necessary to combine state-of-the-art aerospace manufacturing methods with current automotive prototype technology to ensure successful completion of the project. Major areas of emphasis include; master tooling aid development, high temperature epoxy molds, component fabrication, component subassembly and body assembly. These areas will be discussed in detail, along with the completion and final assembly of the lightweight vehicle.

This paper describes a distinct approach in making technological forecasts. From historical data, fuel economy learning curves have been constructed for alternatives such as the Diesel, gas turbine, Stirling, stratified charge, and rotary engines. Assuming that evolutionary development will take place, projections of these learning curves are extended to the 1990 era. The investigation found that no engine is likely to exceed the fuel economy of the Diesel in the next 10-15 years. However, serious questions are being raised regarding the feasibility of controlling nitrogen oxides and unregulated emissions in future Diesel engines.

Results of an automotive technology assessment study are presented to provide a basis of comparison for vehicles with alternative power systems. Factors considered include fuel economy, exhaust emissions, multifuel capability, advanced materials, and cost/manufacturability for both conventional and advanced alternative power systems. To insure valid comparisons of vehicles with alternative power systems, the concept of an Otto-Engine-Equivalent (OEE) vehicle is utilized. Each engine type is sized to provide equivalent vehicle performance. Fuel economy projections are made for each engine type considering both the legislated emissions standards (0.4 g/mi HC, 3.4 g/mi CO, 1.0 g/mi NOx) and possible future emissions requirements (0.4 g/mi NOx). The sensitivities of the fuel economy projections to factors such as engine torque boundary, rear axle ratio, performance criteria, and engine transient response are discussed.