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The efforts of the ISO “Test Variability Task Force” have been aimed at improving the understanding and at reducing brake dynamometer test variability during performance testing. In addition, dynamometer test results have been compared and correlated to vehicle testing. Even though there is already a vast amount of anecdotal evidence confirming the fact that different procedures generate different friction coefficients on the same brake corner, the availability of supporting data to the industry has been elusive up to this point. To overcome this issue, this paper focuses on assessing friction levels, friction coefficient sensitivity, and repeatability under ECE, GB, ISO, JASO, and SAE laboratory friction evaluation tests.

Modern approaches to durability assurance in ground vehicle design are reviewed in the context of recent developments in computer-based analytical and experimental tools for use by designers and development engineers. Examples, using an automotive wheel assembly, are presented to illustrate the application of fatigue analysis in product development. Major challenges associated with the linking of various design tools into integrated networks appropriately configured for industrial problem solving are discussed along with an assessment of the potential benefits to be gained from such integration.

The original design-performance evaluation method of tracks and tracklaying vehicles, proposed by this writer during the WW II, was further developed and enhanced with new experience gained by many researchers. The method is based on the approximation of track action by a number of appropriate wheel actions. It is mathematically simple, and practically unique encompassing detailed track and road wheel geometry, wheel spacing, loads and load distribution together with regular soil strength parameters. It conforms methodologically with evaluation of pneumatic tires and rigid wheels, previously published in a series of SAE papers. The said papers and the present one form a concise engineering outline of Terramechanics for off-road locomotion.

This paper presents an overview of the Driver Performance Data Book under preparation by the National Highway Traffic Safety Administration (NHTSA). It includes a brief discussion of the purpose of the Data Book, the restrictions placed on the development effort, and how it is expected that it will be used by Agency personnel and others. Sample pages from the document are reproduced to illustrate the basic format, and the Table of Contents of each section is presented to identify the major topics covered and indicate the number of pages devoted to each.

A unique system would solve traffic, fossil-fuel depletion, and environmental problems. Dual-mode private and commercial vehicles would be manually driven on streets and automatically controlled on maglev guideways. Busses and freight vehicles without wheels or drivers also used. Proposed guideway speeds: 100kph in cities, and 325kph between cities. System would be safer and have much higher capacity than existing highways or proposed “smart car” systems. One-third meter clearance between cars to be achieved by linear synchronous-motor propulsion. Capacity of single 100kph guideway to equal that of twelve highway lanes, and one 325kph guideway would be equivalent to forty highway lanes.

Current vehicle climate control systems are dramatically overpowered because they are designed to condition the cabin air mass in a specified period of time. A more effective and energy efficient objective is to directly achieve thermal comfort of the passengers. NREL is developing numerical and experimental tools to predict human thermal comfort in non-uniform transient thermal environments. These tools include a finite element model of human thermal physiology, a psychological model that predicts both local and global thermal comfort, and a high spatial resolution sweating thermal manikin for testing in actual vehicles.