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This paper reviews the Pacejka tire performance model that relates the slip to the tire adhesion forces at various normal forces and camber. This model is then presented in a normalized form so the degradation in the coefficient of friction and the value of slip that results in a peak force can be expressed as a function of normal load and camber. With this form of expression, μ and the maximizing slip can be identified directly. Knowing how these factors vary with load and other parameters will allow engineers to determine the best suspension settings.

Proper design of an engine's intake and exhaust system can offer the benefits of torque increase, fuel economy, and emission control. A new concept of intake airflow dynamics is presented, with a multiport model of an intake tube. Fluid transmission line dynamics are applied to a distributed parameter model of straight-tube manifold. This application proved itself to be an excellent way of analyzing the intake system predicting intake pressure waves of an internal combustion engine. With this modeling, transient and frequency responses are obtained to setup a design basis for the intake manifold.

This paper presents the rules, conduct, and results of the 1985 Formula SAE vehicle design competition. Students were challanged to conceive, design, build, and compete with a small formula-style race car. The basic restrictions on the car are less than 610 cc engine with a single carburetor and 23 mm restrictor; wheelbase greater than 1.52 m and various safety equipment. The competition scoring includes engineering design, cost analysis, presentation, acceleration, skid-pad, maneuverability, fuel economy, and endurance. A summary of the design features of each entry is included.

This paper reviews the requirements of a Mini-Baja vehicle, discusses the conflicting design trade-offs, and outlines some of the more successful design approaches in recent years. The design alternatives are discussed in general terms and exemplified with previous vehicles. A complete summary of the vehicles entered in the 1980 Texas Mini Baja is presented.

Most previous studies of entry maneuverability of high L/D vehicles from low altitude earth orbit have been concerned with defining the maximum crossrange performance without regard to the downrange distance. However, for certain “quick return” missions, entry within a limited downrange distance may also be desirable. Results of a study to define the effects of various entry techniques in minimizing the distance to the heel of the footprint, within reasonable heating limitations, are presented. Studies were made for a spacecraft having a maximum hypersonic L/D of 2.2. A computer program was utilized that simulated entry in four phases: 1. An entry pullout phase, 2. A modulated bank angle phase, to suppress skip, 3. A constant bank angle phase, held until a desired heading was achieved. 4. A terminal glide phase at maximum L/D. Any combination of bank angle and angle of attack could be selected for each phase, except Phase 2, where bank angle was modulated as necessary to prevent skip.