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Design analysts, who work with finite element shape optimization, face a daunting task of handling cylindrical parts like a pusher for a crimp. The shape vectors generated by any of the existing methods/tools cannot constrain nodes to move in a circular path. Since the pusher is not a complete cylinder and the loading is only along axial direction, shape optimization was performed after flattening out the cylindrical pusher. The existing shape optimization tools could now be applied to the flat plate. A numerical interpolation method, based on ‘Autodv’, has been used to generate shape vectors. Both weight and stresses have been brought down and the final design was verified with solid finite element analysis.

A case study of the application of topography and shape optimization techniques to the design of a jounce bumper bracket of a pick-up truck has been presented. First a sizing (gage) optimization was undertaken to redesign the jounce bumper bracket. Since the weight was not satisfactory it was decided to try shape optimization. A better solution was obtained. Topography optimization, a relatively new technique of bead formation, was then applied and a still better solution was obtained. All these options were presented to the designer to enable him to make a decision based on manufacturing and other constraints. Although all the three solutions seems to give good results the topography optimized jounce bracket results in the least weight, with the penalty of an additional manufacturing operation.

The transmissibility technique has been traditionally used for evaluating the NVH performance of isolated, rigid structures such as the elastomer mount isolated automobile engine. The transmissibility quantity provides information on how a structure reduces vibration as subjected to dynamic loading and thereby attenuates noise. In the present study, the transmissibility is applied to a non-rigid, plastic structure - the engine cylinder-head cover module. The cover module includes primarily a thin, plate-like cover and the elastomer isolation system. At low frequencies, the cover will behave as a rigid mass and thus display a major peak at its resonant frequency. At high frequencies, the cover will vibrate as a flexible panel and thus display multiple peaks with magnitudes differing from point to point across the cover surface. As a result, the transmissibility calculated would have a spatial resolution, called the spatial transmissibility.