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We employ theoretical and experimental means to examine driver control strategies for use in emergency brake-and-steer maneuvers using ABS-equipped vehicles, and show that the admonition to simply “stand on the brakes” does not necessarily produce the desired vehicle response because the full maneuver envelope of the vehicle is not utilized. Rather, judicious use of vehicle braking in its non-ABS mode is preferred for portions of some maneuvers where maximum lateral control is desired.

The various forms of professional and amateur motor sports all require barriers, fences and deceleration/run-off areas for driver and spectator safety. We examine the translational and rotational kinetic energies involved for various types of race vehicles, and present some comparisons to typical energies encountered in everyday situations. Stopping distance vs. deceleration rates are also calculated, and some simplified trajectory analyses are performed for parts potentially launched during racing accidents.

Many modern vehicles utilize so-called “space-saver” spare tires. Such tires are not fitted to the vehicle and driven on until a tire problem has arisen with a service tire, and are limited in the mileage and speed at which they can operate. They also may have quite different characteristics (rolling radius, tread pattern, contact patch width and length, aspect ratio, stiffnesses, self-aligning torques, etc.) than the service tires with which the vehicle is equipped. As such, they have the potential for presenting significantly different handling signatures to the driver when they are fitted.. In the present work, we present force and moment characteristics for two disparate space-saver spare tires. The tires were tested at the T.I.R.F. (TIre Research Facility), Calspan Corporation, Buffalo, NY.

The subject of qualitative and quantitative evaluation of vehicle handling has received emphasis and study since the first automobiles were constructed. Handling quality can be divided into three distinct regimes: (a) resistance to rollover, (b) steady-state behavior, and (c) transient behavior. Additionally, handling of a modern race car can and often must also be separated into handling characteristics due to mechanical grip and characteristics due to aerodynamic performance. For modern racing cars, rollover solely due to lateral acceleration is unlikely except for a few specialized types of racing cars (e.g., Bonneville). In the present work, we discuss handling from the perspectives of human control performance, vehicle metrics and handling test development. We show that from the point of view of the human operator, certain vehicle characteristics are important if emergency and high-g handling maneuvers are to have a chance of being properly executed by drivers.

Traditional vehicle simulations use two methods of modeling driver inputs, such as steering and braking. These methods are broadly categorized as “Open Loop” and “Closed Loop”. Open loop methods are most common and use tables of driver inputs vs time. Closed loop methods employ a mathematical model of the driving task and some method of defining an attempted path for the vehicle to follow. Closed loop methods have a significant advantage over open loop methods in that they do not require a trial-and-error approach normally required by open loop methods to achieve the desired vehicle path. As a result, closed loop methods may result in significant time savings and associated user productivity. Historically, however, closed loop methods have had two drawbacks: First, they require user inputs that are non-intuitive and difficult to determine. Second, closed loop methods often have stability problems.