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The complex interrelationships which occur between the suspension instant centers and their respective tire contact patches during transient vehicle maneuvers can lead to a reduction in cornering performance and unpredictable vehicle behavior. Analysis of the suspension instant center and roll center locations, and the change in position of these centers as the vehicle rolls, can be used to improve transient handling characteristics in performance vehicles. These properties are analyzed in detail, for short-oval track applications, to demonstrate favorable and less favorable designs. The analysis is performed primarily with kinematic analysis software which is augmented with suspension systems designed and evaluated by the authors.

Light weight quiet small internal combustion engines that meet cost and required reliability parameters are important in the consumer product market as well as in the industrial environment. In the design of these lightweight powerplants, accurate analysis of factors which influence immediate and long-term effects is essential. Hologram interferometry is used to provide a full field view of engine cylinder wall deformations which may lead to noise, fatigue and related inefficiencies. The technique allows for the evaluation of cylinder deformation caused by thermal and mechanical loads. Static loads are applied to predict the deformation of the engine at specific points in the operating cycle.

In the design of automotive and heavy equipment engines, accurate analysis of factors which influence immediate and long-term effects is essential. Fastener torque, thermal and pressure variations are utilized to evaluate basic sensitivity of the engine to these parameters by measurement of cylinder bore and cylinder head distortions. Holographic interferometry was used to measure the cylinder deformation caused by the applied thermal and mechanical loads. A cast iron V-6 engine was used as the test engine. Influences of bolt torquing, as would occur during initial assembly and/or service were evaluated. Pressure on the cylinder walls was simulated by creating a vacuum in the water jackets of the engine block. The effects of thermal loads were evaluated using a temperature controlled liquid flowing through the water jackets. Incremental steady-state loads were applied to investigate the deformation of the engine at specific points in the operating cycle.

An important factor influencing the strength of spur gear teeth is the fillet profile. In the fillet area bending stress and local geometry changes result in stresses and stress concentrations that can, under high loading conditions, lead to failure. This study was conducted to determine if an optimum fillet profile existed, what the shape of the optimum profile is, if the profiles are similar for different pressure angles and the magnitude of improvement that could be expected. New manufacturing techniques such as full-form grinding, near net formed gear blanks and powered metallurgy technology allow the gear designer to put different forms in the root area than the usual trochoid produced by the tip of a hob generating the gear. With the application of these techniques the fillet profiles could be optimally formed leading to strength improvements of up to 40%, with reductions in rotating mass.

Major emphasis on the use of lightweight components in engines has lead to widespread use of polymer intake manifolds. The pulsed flow through these manifolds combined with the lower elastic modulus materials can result in excessive noise under certain speed load conditions. Using full-field optical techniques allowed for the detection and analysis of the resonance behavior in polymer intake manifolds. The test procedures involved techniques including time-averaged holography, with variable excitation sources to identify resonating regions and associated critical frequencies. The results clearly indicate the development of an efficient test methodology to analyze manifold designs for resonance and structural characteristics