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A web based software program has been developed to do a Finite Element (FE) analysis of a simplified driveline system. In the past, an expert analyst had to make a Finite Element Model, analyze and then report results. It has been observed that this process is time consuming besides the difficulties of doing quick parametric studies, geographical location of designers, analysts, etc. The web-based software program aims to solve these issues. The designer could get analytical & Finite element results anywhere around the world (where the designer has access to the web) without any expertise in FE modeling. This software is a joint effort of Engineering and Information Technology (IT) software groups. It is based on Active Server Page (ASP) technology and MSC/NASTRAN technologies combined. Input data deck is prepared from user inputs and submitted over the internet to a remote system, solved and results are retrieved and plots shown in minutes, instead of days earlier.

A case study of the application of optimization techniques to the design of rear-axles-connecting-linkage of heavy trucks with only two rear axles has been presented. The rear axles are made to move in tandem by designing a linkage connecting the two at each of its ends. The linkage locations are determined by the inter-axle-drive shaft, which is a telescopic tube. The drive-shaft is mounted with U-Joints on the two rear axles and follows the bumps and rebounds of the roads with minimal rotation about the lateral axis. Optimization techniques were applied to a planar ADAMS Model to minimize the drive shaft rotation.

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.

A fuel filter system essentially consists of a center tube, which is screwed on to a head and rests against a bowl. A thin circular plate, called end-cap, slides inside the bowl with spline teeth. The fuel filter material is inside the bowl and rests on the end-cap. When the bowl is tightened an input torque is transferred to the center tube and on to the head. It is required to estimate the stresses of the various components when a maximum tightening torque is applied to the bowl. A non-linear large deflection contact analysis of the fuel filter system needs to be performed. A number of contacts between the different deformable bodies, i.e. head and bowl, end-cap and center tube, etc. are resolved for equilibrium.

Automotive drive shafts, which transmit power from the transmission unit to the rear axle are in general straight round tubes. An attempt has been made to explore other possible cross-sectional shapes to improve NVH (Noise Vibration and Harshness) performance. The first natural frequency is a very good indicator of the NVH performance. First, finite element based topology optimization and later topography optimizations were tried out. A number of design solutions were obtained from the study and a comparison has been made. A round drive shaft with a bulge at the center has been proposed for stiffenening the drive shaft to improve the first natural frequency.