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1966 models of General Motors passenger cars and light trucks sold in California are equipped with the General Motors air injection reactor system. This system meets standards for control of exhaust emissions. Saginaw's contribution to this system is the air pump, which supplies supplementary air for the injection system. The Sagniaw air pump is a semi-articulated vane type pump of a positive displacement variety. The pump has a design displacement of 10.3 cu in. per revolution with high volumetric efficiency and low horsepower consumption. In the development of the pump, it was necessary to establish durability requirements consistent with the life of the vehicle, providing satisfactory performance without maintenance. It was necessary to perform laboratory tests to insure compliance with these requirements. The Saginaw air pump satisfies all the design objectives and has been accepted for use on 1966 vehicles sold in California.

A driving simulator development project at the Systems Engineering and Technical Process Center (SE/TP) is exploring the role of driving simulation in the vehicle design process. The simulator provides two vehicle mockup testing arenas that support a wide field of view, computer-generated image of the road scene which dynamically responds to driver commands as a function of programmable vehicle model parameters. Two unique aspects of the simulator are the fast 65 ms response time and low incidence rate of simulator induced syndrome (about 5%). Preliminary model validation results and data comparing driver performance in a vehicle vs. the simulator indicate accurate handling response dynamics within the on-center handling region (<0.3g lateral acceleration). Applications have included supporting the development of new steering system concepts, as well as evaluating the usability of vehicle controls and displays.

While the collision of cars is not an exact science, the 1967 General Motors energy absorbing steering column shows what can be done in one area to improve the finished product through the achievement of a sequence of design goals. It is felt that, based on tests of a great number of vehicles, the energy absorbing column will definitely improve the driver’s chances of survival in a significant range of head-on collision conditions.

This paper describes the development of the new energy absorbing steering column which is standard equipment on all 1967 General Motors and several competitive cars. The paper includes a description of the initial concept, the development stages of the final design, performance goals, and testing procedures. It details problems presented by the different design characteristics of the various car models.

A new full-scale automotive aerodynamics wind tunnel has been constructed and placed in operation at the General Motors Technical Center. Tunnel performance and flow quality specifications have been met through appropriate choices of design criteria, construction techniques, and inspection procedures. Test section size, two balances, and a boundary layer suction system provide a broad range of full-size and reduced-scale model test capability. Test support, operational and engineering environments, and equipment have been specifically tailored for automotive aerodynamics requirements.

A stipulation of the 1974 Federal Motor Vehicle Safety Standard (FMVSS) 215 is that no portion of the test vehicle is permitted to contact planes A or B of the test pendulum. Planes A and B are surfaces located, respectively, below and above the impact ridge of the federally designed pendulum. One situation in which the bumper could contact plane B, and therefore fail the test, occurs while the bumper and pendulum are separating after impact. The return stroke of the energy absorber can delay bumper-pendulum separation and influence test results. This report presents the technical procedure used to establish energy absorber rebound performance characteristics and the modifications made to the General Motors hydraulic-pneumatic design to obtain rebound control on certain 1974 car models. FMVSS 215 also necessitated the application of energy absorbers to the rear bumper systems of most 1974 vehicles.

The GT-309 regenerative gas turbine engine is the latest in the series of heavy duty vehicular gas turbine engines developed by the General Motors Research Laboratories. This new engine incorporates a major engineering advance, which not only improves part-load fuel economy to the point that rivals the diesel installed economy, but also provides engine braking equal to the rated output of the engine. These improvements result from a novel system called Power Transfer, which connects the gasifier and power turbine shafts through a controlled torque coupling. This paper describes the system, its several applications, and development and evaluation studies.

General Motors has developed a supercharged version of its 3800 V-6 engine. It utilizes a Roots type supercharger mounted in the Vee of the engine, attached directly to the intake manifold. This engine provides increased performance with an excellent balance of fuel economy, as well as a high level of pleasability and reliability. The objective was to achieve the character of a larger, eight cylinder, engine while maintaining the fuel efficiency of a six cylinder. This would provide an engine well suited to market and environmental needs. Various methods of boosting, structural development of the engine, and control systems considerations, were evaluated. Final designs were selected based on total system quality, reliability and simplicity. This paper outlines the evaluation, selection and development of this new powertrain and technology.

Some of the more general types of dynamic vibration that exist in aircraft, particularly the powerplant components, are reviewed for reciprocating and turbine engines as well as helicopter and unconventional drive systems. The responsiveness of various components to the source of excitation, resulting in either resonant or nonresonant (forced) vibration, is discussed. The importance of evaluating the fatigue life of a component at varying load conditions, both in the laboratory and field, is stressed.

The General Purpose Work Station (GPWS) is a laboratory multi-use facility, as demonstrated during the Spacelab Life Sciences 1 (SLS-1) flight. The unit provided particulate containment under varying conditions, served as an effective work space for manipulating live animals, e.g., rats, served as a containment facility for fixatives, and was proposed for use to conduct in-flight maintenance during connector pin repair. The cabinet has a front door large enough to allow installation of a full-size microscope in-flight and is outfitted with a side window to allow delivery of items into the cabinet without exposure to the spacelab atmosphere. Additional support subsystems include inside cabinet mounting, surgical glove fine manipulations capability, and alternating or direct current power supply for experiment equipment, as will be demonstrated during Spacelab J.

This paper presents an optimization model that was developed to generate optimal alternative sets of data elements for crash event data recorders (EDRs) on commercial motor vehicles, since EDRs can provide important information about crashes to improve vehicle safety. The input data for this optimization model was from the following United States Department of Transportation (USDOT) reports: Development of Requirements and Functional Specifications for Crash Event Data Recorders (EDRs) on Commercial Motor Vehicles and EDR Volume II - Supplemental Findings for Trucks, Motorcoaches, and School Buses (May 2002). The purpose of this optimization model was to provide useful and cost effective alternative sets of EDR data elements for a “real world” application.

Flyover noise levels of turbojet-powered airplanes are dominated by the low-frequency roar of the jet-exhaust noise at both takeoff and approach power settings. Jet-noise suppressors developed for these turbojet engines did reduce some-what the noise levels under the takeoff flight path but did not reduce the levels under the approach flight path. Low-bypass-ratio turbofan engines produced less jet-exhaust noise than the turbojet engines, but the discrete-frequency components of the turbomachinery noise were more prominent. A research program, conducted for NASA, showed that the installation of acoustically absorptive duct linings could yield significant reduction in the level of the turbomachinery noise, on the JT3D-powered transports at approach power settings. Expectations relating to installations of similar material on JT8D-powered transports are described.

A numerical method for generating a blockloading profile from a rainflow histogram is described. Unlike previous techniques, this method produces a blockloading profile which, when rainflow-counted, yields a rainflow histogram identical to the original. When implemented with modern data acquisition and signal-processing techniques, this generation method provides a means of developing blockloading test profiles which are correlated with actual service data. This key benefit elevates existing simple testing systems as useful and productive tools despite the emrgence of more complex testing systems.

The provision of two-way communications between the central traffic control center and all vehicles, which are equipped with route guidance systems (RGS), makes it possible to assemble very efficiently a continuous estimate of the prevailing dynamic or time-varying O-D (Origin-Destination) matrix. This paper describes the mathematics of a four step procedure for developing such a time varying O-D matrix from vehicle probe data and discusses the important statistical limitations of the final O-D estimates. It is shown that, unless there is a very high level of market penetration in the network, the resulting O-D estimate will contain such a high level of statistical uncertainty as to render it of limited practical value.

Various conditions can cause an aircraft to assume a roll or tilt angle on the runway, causing the nose tire(s) to produce significant uncommanded cornering forces if the nose gear is free to swivel. An experimental investigation was conducted using a unique towing system to measure the cornering forces generated by a tilted aircraft tire. The effects of various parameters on these cornering forces including tilt angle, trail, rake angle, tire inflation pressure, vertical load, and twin-tire configuration were evaluated. Corotating twin-tires produced the most severe cornering forces due to tilt angle. A discussion of certain design and operational considerations is included.

This paper announces the intention of the SAE AS-1 Committee to standardize on a common framework for modeling and defining aircraft-store logical interfaces, called GASIF. The paper then advocates a common framework that might serve as a suitable starting point for this project. The purpose of GASIF is to foster greater interoperability between aircraft and stores through coordinated standards development and programs. FIELD OF APPLICATION - The field of application for this paper is military aircraft/store avionics, where a ‘store’ may be defined as any in-flight separable device (such as an air-launched weapon) that when loaded on an aircraft allows it to perform a specific mission.

The CATHODE RAY TUBE (CRT) has long been considered for use as a vehicular display device. As time has passed, however, most of the questions or objections about its use have been overcome. With the tendency towards even more highly feature-oriented automobiles in the future, a comparison between the V-CRT and other historically competitive display devices reveals the CRT as an extremely viable alternative in vehicular instrumentation.

Equations are derived which describe and relate the magnification, viewing angle and reflected illuminance of convex mirrors as used in automotive applications. The derived equations are compared to those for plane mirrors. Using these equations, the viewing angles of automotive rearview mirrors are calculated and depicted. The blind zones are defined in terms of the viewing angles, obstructions to vision, perceptibility limitations, and the lateral separation of vehicles. Various strategies for overcoming the blind zones are discussed.

This paper on single sided calipers traces the way in which experience of the difficulties in maintaining consistent performance with minimum drag for fuel economy is leading to wider use of sealed enclosed sliding systems for calipers accepting a small space penalty for the greater durability which is ensured.