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Results of an evaluation of possible advanced brake components and systems for motorcycles are reviewed. Potential improved conventional brake components included: friction materials aimed at improving wet brake performance; and components affecting brake system feel properties. A prototype all-mechanical antilock brake system was evaluated. Results showed improvements in performance may be realized via all three of these areas, based on prototype results that might apply to future designs.

An analytical method applicable to design and development of antilock brake systems is described. Dynamic components of antilock systems --- including vehicle, sensor, and modulator--are examined using nonlinear feedback control techniques. An overall design approach is illustrated via an example involving a motorcycle front brake and typical pneumatic modulator. A computer simulation is used to generate time and frequency responses of system components. These data are used to identify the preferred feedback structure. Results show that a stable antilock limit cycle can exist for wheel angular acceleration feedback, among other possibilities. Overall the method and results can provide additional insight into detailed requirements for antilock components and systems, and may hold potential for reducing development time and costs.

An analysis of antilock brake system dynamics, based on nonlinear control theory, was performed. Results were used to define initial performance and design requirements for a prototype fluidic motorcycle antilock system. The analysis emphasized the frequency response of system components and effects on stopping performance and stability. Results showed wheel angular acceleration provides a feasible single loop feedback for antilock control; wheel angular jerk is probably not a desirable primary feedback variable; nominal design requirements for modulator and controller exist that represent a compromise among high and low μ performance, stability, roughness, and signal-to- noise ratio; net time delay between modulator and brake caliper is a key design parameter and should be investigated more thoroughly.

A theoretical and experimental investigation of the effects of antilock braking (ALB) on motorcycle braking in a turn (BIT) is described. The analyses involved computer simulation of the dynamic interaction among rider, motorcycle, ALB, and roadway during BIT maneuvers; and instrumented full scale BIT tests with expert and novice riders. The analyses and full scale tests used an example all mechanical, independent front and rear ALB system. The results showed that ALB can help maintain motorcycle stability in straightline and gradual turns at high and excessive brake force levels. In more severe turns, the motorcycle can capsize at low brake force levels, below those which are typically needed to trigger ALB operation. As a consequence, from a fundamental standpoint, contemporary conventional ALB systems cannot be considered to influence or improve motorcycle stability during limit braking in moderate or near limit turns.