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The objectives of this third edition of an SAE classic title are to provide readers with the basic theoretical fundamentals and analytical tools necessary to design braking systems for passenger vehicles and trucks that comply with safety standards, minimize consumer complaints, and perform safely and efficiently before and while electronic brake controls become active. This book, written for students, engineers, forensic experts, and brake technicians, provides readers with theoretical knowledge of braking physics, and offers numerous illustrations and equations that make the information easy to understand and apply. New to this edition are expanded chapters on: • Thermal analysis of automotive brakes • Analysis of hydraulic brake systems • Single vehicle braking dynamics

The Findings presented in this paper are based upon the investigation and reconstruction of more than 250 commercial vehicle accidents. Practical methods yielding acceptable results in terms of speed determination and fade and temperature prediction in truck run-away accidents are presented. The importance of accurate and complete data collection with respect to accident scene, mechanical condition of the vehicle, and driver human factors are discussed. The effects of complete, partial and no-wheel lockup on accident reconstruction are discussed for straight and out-of-control motion of the vehicle, including Jack-knifing. The importance of front wheel brakes is considered. The engineering concepts used in the analysis of accidents involving brake fade are presented including factors such as Jake brake, brake adjustment, and heat checking of drums. Driver factors are also considered. Truck rollover mechanics as it applies to braking accidents is reviewed.

The purpose of this paper is to outline and analyze the functions of a braking system, to review the elements of an objective and meaningful braking standard, to evaluate Federal Motor Vehicle Safety Standard 105-74, and to recommend revisions to FMVSS 105-75.

The object of this paper is to investigate the effects of two-way brake proportioning for improved braking in a turn. The theory of two-way proportioning is discussed. A typical design study is presented and verified by experimental data for a passenger car. The principles discussed apply to passenger cars, trucks, and combination vehicles.

This paper presents equations for determining the convective heat transfer coefficients of solid and ventilated disc brakes. Analysis of data indicates that the cooling capacity of a ventilated rotor is sharply reduced at lower speeds, and most cooling is provided by the increased surface area. A general relationship derived from road test data is presented that yields the heat transfer coefficient for both disc and drum brakes of commercial vehicles.

Most motor vehicles operating on our highways today are designed to exhibit high levels of straight-line braking performance without providing sufficient stability during combined braking and steering maneuvers. A basic engineering analysis is presented that allows optimum values of brake balance to be determined for both straight and curved braking. The effects of brake fade on brake balance are discussed. Different wheel antiskid systems are analyzed, and test results are presented for three domestic vehicles. A methodology for determining expected safety benefits of advanced brake systems is reviewed.

This paper reports the results of a study which had as its aim the determination of braking performance currently achievable by buses, trucks, and tractor-trailers, and the improvement of this performance by use of advanced braking systems. Both vehicle testing and analytical techniques, including dynamic modeling and simulation, were used in the program. Performance qualities essential to braking systems are enumerated, which, when given quantitative definition in the light of performance achievable, can form the basis of rational performance requirements for commercial vehicles.

An engineering analysis of vehicle braking is presented in terms of the utilization of available road friction. Physical relations are derived which allow the determination of optimum brake force distribution on front and rear wheels as a function of axle loading. Ideal braking distribution curves are shown for a typical vehicle in the loaded and unloaded conditions. A technique is suggested for rational design of braking system parameters. It is applied to the case of a two-stage proportioning system, and is validated by experimental data from tests using a specially equipped light truck. It is concluded that a proper design analysis can establish a combination of braking system parameters which results in improved utilization of available friction. A simple, self-adjusting brake proportioning system can be a highly cost-effective safety device for truck use.