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The development of vehicular gas turbine engines to operate at temperatures up to 2500°F has been in progress for some time. The purpose of this paper is to review the rationale behind this engine, to highlight the major hot flowpath components being developed, and to provide information on the progress of this program.

The paper describes the factors which must be considered when assessing the suitability of a material for a rotary regenerator disc which runs at 1850°F. Mechanical and thermal stressing, thermal stability, and corrosion resistance are analyzed, using the properties of type CPD-5 material. This is a new lithium-alumino-silicate glass ceramic developed by Corning Glass Works. The environmental conditions assumed are those found in the 2500°F turbine inlet temperature engine which is being developed by the Ford Motor Company.

The 1974 Toyota Corona has been drastically changed to accomodate the required devices for emission control and to comply with safety standards. The handling and stability characteristics has been improved as well as vehicle performance. Steering effort and interior noise levels have been reduced. This paper presents the details of design concepts and the techniques that were employed to produce these improvements.

The recently introduced Volkswagen Golf, or Rabbit as it is known in North America represents the newest addition to the line of passenger cars manufactured Volkswagenwerk AG. The considerations applied in the establishment of design goals in the handling sector are discussed in the context of a description of the vehicle suspension system. The state of knowledge and administrative regulation of vehicle handling response characteristics are discussed in the context of design goals.

This paper presents a review of Curtiss-Wright's efforts to identify or develop successful apex seal/trochoid sealing systems for the rotary engine. Included are descriptions of the various wear test rigs utilized to evaluate apex seal/trochoid coating combinations. Laboratory seal-coating screening procedures are detailed along with engine test results. Seal-coating design considerations including factors affecting seal loading and wear are described. Data are presented on a newly developed plasma spray coating containing titanium carbide.

The radial lip shaft seal is a necessary, important component of modern machinery. A multitude of materials and designs exist for a variety of applications. The manufacturer must choose a seal type that will satisfy the conditions of the application with high reliability and long life. Confidence in the choice is gained through functional testing. Typical functional tests involve four to twelve seals. These tests are usually run under accelerated conditions. The seals must perform without leakage for a given period of time (typically 100-500 h). This technique (success testing) provides limited information with low confidence levels. Nothing is learned about the failure rate distribution of the general population of seals. A more meaningful statistical procedure, Weibull analysis, is discussed and applied to seal testing. Experimental data are supplied and analyzed.

The development of the Datsun pickup is traced from the post-World War II model with a wooden body, to the modified passenger car, to the current independent truck model. Some differences between the Datsun pickup and other Japanese-made trucks and American-made trucks are discussed. It is noted that the Japanese stress load efficiency: the Americans do not. Problems with size-dependent taxation rates; crowded roads; and scarce, expensive oil supplies have all led to a compact, economical design. Also discussed are the truck's adaptability to export destination requirements and its body construction.

A brief comparison of human performance in a man-machine system and in a Vehicular Transport System is carried out. Factors influencing the human performance are cited. Some of the problems connected with research work pertaining to VTS are summarized. Results of an experimental investigation, in which effects of road noise and vehicle speed on human performance were studied, are reported. The findings of the investigation indicate that noise is a significant variable as far as human performance in a VTS is concerned.

Inadequate training of the driver accounted for 70% of the 61 serious auto accidents investigated over a period of three summers by a team of field researchers. One conclusion reached following the study was that licensing officials must be granting licenses to drivers lacking sufficient preparation. Another aspect of the study dealt with the use of restraint systems. Figures show that, of the 138 persons injured in these accidents, only four were restrained at the time of impact.

This paper discusses the unique characteristics of the BMW 520. Beginning with overall specifications of the vehicle design, it proceeds to discuss in detail the front-wheel suspension and rear-axle systems. The adaptability of the suspension system to the requirements of diagonal ply conventional or radial tires is stressed, as is the simplified installation and maintenance of the front-wheel subassembly. The relatively friction-free steering system and the reduced steering effort achieved by the camber-offset axle are noted, along with the measures used to control steering vibration and wobble, as features incorporated in the BMW to achieve reliability, ease of maintenance, safety, and crashworthiness.

Reliability in a finished product can only be ensured when the designer has taken care to achieve the optimum solution to the sum of the needs of a particular set of circumstances. To follow this design philosophy, the designer must determine the function of the product, the length of time it will be required to operate correctly, and the amount of maintenance which is acceptable. When the necessary knowledge and information have been obtained from all available sources, then it is time to translate this concept into a product design. The engineering drawing is the message which communicates a reliable design to the production department so that it may be converted into a reliable product. The key to successful design is collaboration among as many designers as possible to maximize the amount of information and the number of ideas available, with one “manager of design” to coordinate their activities.

A recently completed research program has dealt with the problem of determining the influence of tire construction properties on vehicle braking and handling performance. Several tire properties that affect vehicle dynamic response have been identified and their effects quantitatively determined. Laboratory testing of a large sample of tires has shown that aspect ratio and basic construction type (that is, bias, bias-belted, radial) can significantly affect tire peak braking coefficient and cornering stiffness. The results of computer simulation studies and experimental tests with four automobiles have shown that the effect of changes in the peak braking force coefficient of tires on the average longitudinal deceleration of vehicles with fixed brake proportioning was small.

Results which have been obtained from flat-bed tire tests and linear-range steady-turning vehicle tests show that tire-in-use factors have a large influence on the normal driving performance of passenger cars. Test data for bias, belted-bias, and radial tires have been gathered to quantify the effect of inflation pressure, tread wear, and shoulder wear on tire shear force performance. A mobile tire tester has been used to measure maximum traction characteristics for worn and under-inflated tires on wet and dry pavements. The importance of the interaction of steering compliance with tire force and moment properties has been examined.

Most of the studies concerning wet skid resistance of tires concentrate on the effect of a single factor, the other variables being kept constant or assumed to be constant. In the Netherlands, the Vehicle Research Laboratory of the Delft University of Technology, in cooperation with a working party of the Institute for Road Safety Research (SWOV) has conducted extensive series of measurements according to statistical multifactor test programs. The wet skid resistance is rated by three coefficients: The peak value of the normalized braking force, the locked wheel value, and the maximum of the normalized side force. Special test programs are described which aim to investigate the influence of road surface parameters, such as texture depth and SRT values (British Pendulum Tester), and of tire parameters on wet skid resistance. The tire parameters consist of tread factors, compound factors, and a carcass stiffness parameter.

Earlier VW driving simulator studies showed the relationships among subjective driver judgement, objective parameters and a vehicle parameter TB. The present series of tests was run to determine the effects of the steering ratio iLK with combinations of this parameter TB. The driving task was more difficult than those in earlier studies: the test subject tried to avoid suddenly appearing obstacles. This made it possible for the test subjects to become involved in critical situations, and for conclusions to be drawn from review of the potential accident sequence, as influenced by the vehicle parameter TB and the steering ratio. The report then presents examples to illustrate the effects of tire parameters and load parameters on the vehicle parameter TB, in a variety of different vehicles.

This paper discusses the cornering characteristics during the progress of tire wear and how the stability and controllability of a vehicle varies in the various stages of tire wear. With the introduction of tire parameters appropriate to represent the characteristics of tire construction, the method of calculation of the cornering characteristics of a tire is proposed in this paper. Furthermore, this paper shows the values of tire parameters in the various stages of tire wear in both cases of bias belted and radial tires.

The paper presents data showing the effects of the state of wear, structure, load, and inflation pressure on the cornering stiffness and aligning torque stiffness of typical passenger tires. A method is introduced and applied for assessing contributions of local elements of the tread interface to the cornering force, the cornering stiffness, the aligning torque, and the aligning stiffness. There is also a further identification of the contributions to the aligning torque from fore and aft interfacial stress distributions and from lateral stress distributions. Pneumatic trail is redefined in the light of the interfacial measurements, and values are established for various operating conditions, states of wear, and tire types.

The report starts by outlining some concepts regarding the forces and the moments which act on a tire. Some general characteristics of indoor cornering force machines, along with their limitations, are then examined. This is followed by a detailed description of a method of measuring tire-vehicle curves on a steering pad. The method, based on experience obtained by the use of mathematical models, permits a quantitative evaluation of the stability and the steering of a vehicle under steady state working conditions, on both wet and dry tracks. It is also shown that certain aspects of the vehicles behavior in transient conditions may be deduced from the data obtained. The method is valid for both cars and two-axle trucks and it is illustrated with some examples.

Factors which govern the selection and application of a computer based Real Time Data Acquisition System are identified. The impact of programming language level as it affects both hardware and personnel requirements are noted. Interface considerations with the laboratory test facility are presented.