Frequency Domain Analysis of 2-Wheeler Systems 2020-01-0476

Most automotive companies validate their vehicle designs by running vehicle on the durability proving grounds. Part fractures and collisions between two components are common failures observed during proven ground testing. Laboratory testing and FEA simulation are used to validate designs in the concept stage as it consumes less time and cost as compared to proven ground testing. The lab testing and simulation process both have their own limitations. It is difficult to incorporate effect of multi-direction input loading (x, y, z) with single direction loading in laboratory testing due to restrictions with electrodynamic shaker testing. However, in simulation, multi direction input can be easily incorporated but often actual vehicle measured test track data is not available in the early design stage.

In the present work, Modern methodologies have been employed [ref 1, 2] in frequency domain to validate design in FEA simulation. First, relative random response calculation is performed for calculating the probability of collision between parts of motorcycle rear cowl. Second, multi-channel loading (x, y, z) on the front cowl is used to derive a simple single direction (surrogate) loading which has similar impact in terms of structural response (stress and fatigue). This derived single direction loading can be used efficiently in shaker testing. Third, a standard input load envelope is created in such a way that it includes all set of possible loading scenarios for a motorbike fuel tank assembly. This standard input load can be used at an early stage of design so that it helps in predicting component failure in FEA simulation.