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The “identification of systems” is a generalized form of curve fitting pertaining to systems for which a mathematical model is known, and for which input/output data is empirically available, but for which actual values of parameters in the model are unknown and are sought. A technique for identification (that is, determination of parameters) in second-order, dynamic systems is presented and applied to a typical system; namely, a two-axle rubber-tired vehicle. The scheme is based on establishing a set of system model equations and their use with system response data to define one or more residue functions in a manner analogous to the defining of an error function in curve-fitting by the collocation method. A performance index is defined by treating the residue as a measure of least squares fit, and the parameters are then determined by finding the set of values which simultaneously makes all the first partial derivatives of this index with respect to the parameters vanish.

A new concept of a ductile iron integral steering arm, brake caliper support, and steering knuckle has been developed. This has inherently higher reliability, fewer fasteners, and fewer human variables than the assembly it replaces.

The various computer techniques for simulation of dynamic mechanical systems are described. An example problem is solved, using the analog computer, a special purpose digital program, an analog-to-digital simulation language (MIMIC), and a problem oriented language (DYANA). The various methods are compared for time expended and efficiency in obtaining a solution. A number of typical automotive simulation problems are briefly described. The current and potential impact of time sharing and computer graphics systems on engineering simulation is discussed.

Safety performance of an experimental windshield with a thin, chemically tempered inner pane is compared with the standard windshield and other experimental windshields. The chemically tempered windshield has a penetration velocity of 35 mph compared with 26 mph penetration velocity for the standard windshield and has lower peak head accelerations than other types used in the experiments. The windshield tested produces a bulge on impact, which decelerates the head over a long distance with low accelerations. The bulge or pocket is lined with particles that are less lacerative than the standard annealed glass.

A system for retrieving specific design information on parts to facilitate their reuse in new designs where applicable, and to assist in standardization programs to eliminate existing duplicate or near-duplicate parts. The technique adapts itself to data processing and for use in analytical studies outside of the engineering design area.

This paper describes experimental and analytical approaches which were developed for the purpose of planning, designing and tuning up not only steady state but also dynamic characteristics of the vehicle maneuvering performance. As regards experimental approaches, outlines of the testing methods and relationship between the measured typical characteristics and the drivers' feeling are presented. They were investigated and developed in order to qualify the general characteristics of produced vehicle dynamics, effectively and accurately, and to apply the results to the vehicle design. As regards analytical approaches, the seven degrees' theoretical model is introduced. It is established for the purpose of analyzing the influences on vehicle performances by changes in design parameters, including the lateral rigidity of tires, the torsional rigidity of the steering system, and some nonlinear dampings in steering and suspension systems.

After a short introductory consideration of wheel suspension layouts, the influence of the suspension on major vehicle characteristics in the steady-state condition is investigated and the theoretical results compared at various points with measurements made on the VW 411. In the second part of the paper, the front and rear suspension and the safety steering system of the VW 411 are described in detail.

Buick engineers are well pleased with their '69 Chassis. Benefits of a unique front suspension camber curve are documented. The effects of various suspension parameters on ride and handling are explained. These were varied independently of one another in the course of evaluating over 30 suspension configurations.

This paper gives an interim assessment of the characteristics of five smokemeters generally available in Europe which are currently under investigation on a cooperative basis in seven countries. This coordinated test programme, begun in 1967 by a Smoke Measurement Sub-Committee of the Coordinating European Council (for development of performance tests for fuels and lubricants) has also investigated alternative test methods, ranging from the constant full load, steady speed test to the so called “free-acceleration” method, on 60 different types of vehicle, representative of those in current use in Western Europe. The results of these tests are summarized, and it is concluded that the basic test for prototype approval for smoke emission level is that carried out as a series of full-load speeds, either with the engine on the test bed or with the vehicle on a chassis dynamometer.

The authors discuss the use of Tramasaf, a laboratory instrument that will test the energy absorption capability of automotive components, and will concurrently measure the extent of trauma to the human forehead. The most recently published biomechanics data has required a revision of the original development goals for the device. The paper describes these new goals, the stage of the progress, and some applications which verify the utility of the device.

An experimental investigation, conducted by an SAE task force to establish correlations between diesel smokemeters is described. Correlations between sampling meters (Bosch spotmeter, BP-Hartridge), opacity meters (USPHS, Beckman 912), and exhaust soot content are presented.

As the demands for materials with improved high-temperature properties continue, more research is being directed toward combining materials into composites to provide properties not available in a single material. An excellent example is a coated metal where the corrosion and oxidation resistance or other properties of an alloy are improved or modified by a thin layer of ceramic, cermet or other metal bonded to the surface. Early developments during World War II and continuing research have produced a number of high-temperature coatings which provide a designer with a unique method for extending a specific materials capability. This paper is a brief review of some ceramic, cermet, and metallic coatings which indicates the scope of the coating development and applications.

The results of recent dynamic load measurements on human skull and patella bone, conducted with less-than-1-sq-in. penetrators, are discussed in relation to previously reported skull impact data from larger contact areas. These medical data are compared to the dynamic response of a large variety of natural and synthetic plastic materials, for use in trauma-indicating headform and kneeform design. Several bodyform designs are proposed as research tools.

Modern gas turbine engines require superalloy components which have a combination of strength at high temperature and resistance to oxidation and sulfidation attack not obtainable with conventional alloys. These requirements are met by a composite of strong superalloy bodies protected with metallic diffusion coatings, formed by alloying the surface with aluminum and other elements. Novel processing methods are frequently required to meet the needs of today's increasingly sophisticated applications. By working together, engine producers and coating vendors have been able to develop procedures to meet these needs.

The need for surface protection of nickel base alloys to prevent hot corrosion and/or sulfidation is discussed. Results of controlled engine test cycling and the rig testing of turbine blades are discussed to establish laboratory test correlation. The relative corrosion resistance of a number of commercial alloys is shown, and the response of these alloys to corrosion resistance with protective coating is covered in relation to their limitation in erosion/oxidation deterioration. Finally, some technology results and general methodology applied to electrophoretic processing for applying coatings of aluminum and combinations with chromium are described. The processing advantages and disadvantages of this coating process and general results are compared with present production.

The use of surface coatings in industry is rapidly increasing. Surface coatings, used principally for their wear qualities, can be divided into three broad categories: chemical platings, hard facings, and flame spraying. Processes are briefly described; examples are given of the uses of the surface coatings produced; and comparisons are made. Particular attention is given to the various flame spray processes and coatings. The importance of particle velocity to the qualities of flame spray coatings is demonstrated. Examples are given of some recent advances in the technology of flame spray surface coatings, and related data are presented. Porosity of coatings and porosity measurement techniques; efficacy of epoxy sealing of coatings for enhanced corrosion protection; very high purity plasma-applied compositions; and the use of plasma coating techniques to fabricate parts are discussed.

Initially, wire flame spraying was only capable of spraying low melting point materials such as zinc and aluminum. These coatings were used basically to achieve anodic corrosion protection. New flame spraying techniques such as the combustion powder process enabled industry to spray ceramics, self-fluxing alloys, and cermet mixtures. Use of fused coatings of self-fluxing alloys offered materials with greater resistance to wear, erosion, and abrasion. A further refinement in spraying techniques was plasma spraying with nontransferred arc equipment which allowed materials with extremely high melting points, such as tungsten, to be sprayed. With these newest developments, flame spraying offers a wide spectrum of material selection to solve most of the wear problems in industry economically and efficiently.

A new, nonlacerating automobile windshield has been developed. It uses thin chemically strengthened glass.Concussion forces are limited to a safe level equal to or below that found in today's conventional windshields. This paper describes the windshield, tells why it works, and describes the development test program.

This paper reviews, from the operational standpoint, basic design, construction, and operation of a jet runway. In basic runway design the controlling factors are usually site location and climatology. A prime requisite during the construction of a new jet runway is the need for a high coefficient of friction between the airplane tire and the runway. An analysis of factors affecting runway design such as texturing of surfaces, drainage requirements, in-runway lighting, seal coating of surfaces, and runway grooving is presented. Further complicating the problem of runway design, natural elements such as water, slush, ice, and snow have to be considered and provision for the elimination of accumulations must be made. If jumbo jets are to be operated safely and reliably, jet operational runway problems must be solved.

The Phase III program for development of the U.S. Supersonic Transport was initiated on January 1, 1967. This program includes design and flight qualification of the engine, and 100 hours of flight test in two prototype aircraft. The GE4 Phase III development program, now entering its third year, has passed several major milestones. Prototype engines have been built and tested to thrust levels in excess of 63,000 pounds. Component tests, sea level engine tests, and simulated flight testing are being conducted and results are described. A general description is provided of the engine, its performance, and the design features to meet the requirements of the commercial Supersonic Transport. Technology advancements in component design, materials and joining techniques are described as they relate to the development program. A brief discussion of development problems encountered and their solutions is included.