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A review, analysis and enumeration are presented of factors relevant to motorcycle airbag feasibility research. This includes: an update of the status of related research in the motorcycle airbag feasibility field; relevant experience and factors from the car airbag field; additional unique factors and considerations for motorcycles; and the potential need to address motorcyclist out-of-position riding; other sizes of riders; motorcycle seating layout variation; resistance to and consequences of unintended deployment on a motorcyclist; neck injury criteria and dummy neck biofidelity; injury risk-benefit considerations; environmental exposure on motorcycles; and discussion of feasibility definition and factors.

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.

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.

An updated evaluation of the effects on predicted injuries of an example crush protective device (CPD) proposed for application to All-Terrain Vehicles (ATVs) is described. As in previous evaluations, this involved extending and applying the test and analysis methods defined in ISO 13232 (2005) for motorcycle impacts, to evaluate the effects of the example CPD in a sample of simulated ATV overturn events. Updated modeling refinements included lowering the energy levels of the simulated overturn events; accounting for potential mechanical/ traumatic (compressive) asphyxia mechanisms; refining and calibrating the force-deflection characteristics of helmet, head, legs and soil so as to reduce potential over-prediction of head and leg injuries; and calibrating the simulation against aggregated injury distributions from actual accidents.