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Vehicle frame evaluation at early stages of product development cycle is essential to reduce product turnaround time to market. In conventional approach of virtual validation it is required to evaluate the strength of the vehicle structure to account for the standard Service Load Analysis (SLA) loading conditions. But this paper describes on the strength analysis of scooter frame with derivation of critical static load cases. The critical load cases are extracted from the load-time history while the vehicle was simulated on durability virtual test rigs which is equivalent to proving ground tests. This methodology gives the better accuracy in prediction of stress levels and avoids the overdesign of components based on traditional validation technique. There is significant drop in stress levels using the critical load case approach as compared to conventional load case method.

This paper describes an investigation of the suitability of FE analysis using the virtual fluid mass (VFM) in fuel tank validation. It produces a mass matrix which represents the fluid coupled to a boundary consisting of structural elements and other effects, such as free surfaces, planes of symmetry and infinite fluids. The incompressible fluid produces a mass matrix defined with full coupling between accelerations and pressures on the flexible structural interfaces. This capability is used to model fuel tank with fuel filled inside. Hence, using the VFM method modal analysis is performed keeping the fuel tank 90% filled and results are compared with physical testing. The VFM method is much more reliable and accurate than the NSM or density adjusted method. The modal frequencies obtained in VFM technique are in proximity with the physical testing results. Further, the fuel tank and its mountings are evaluated for frequency response analysis with excitation in vertical direction.

At present, vehicle testing in laboratory is one of the important phase to quicken the product validation process. In the early phase of laboratory testing it is required to evaluate the strength of the vehicle structure through physical rig setup which represents the consumer’s usage. Two and Multiple poster input excitation are among the laboratory rig testing to represent the actual road are used to predict the durability of vehicle components. The road inputs through the poster are known as drive files, a feedback controlled system which reproduces the track or real road recorded specimen’s accelerations, displacements and strains in laboratory. Derivation of drive files in poster testing requires iteration of physical specimen to exactly replicate the actual road. This paper discusses about generation of drive files as inputs for poster actuation with virtual model(as a substitute for actual model)which is applicable in areas of vehicle durability and ride comfort studies.

Scooter segment growth is tremendously increasing in India. The increased competition challenges automotive manufacturers to deliver the high quality and high reliable product to the market. Higher reliability involves increased durability testing which involves time and cost. Stress testing a part of durability is initially conducted on prototype vehicles for structural design validation and then later on production units to ensure its structural integrity. The obtained data from the tests can be used for future structural design improvements. Scooters with small tires, suspension limitations transfers more loads to structure, challenges engineers to design robust structure without compromising on weight much. It is necessary to look at Real World Usage Pattern (RWUP) and to create a stress life cycle block for simulation of accelerated testing, thereby optimizing the testing time and the development costs.