DESIGN, MODELING AND OPTIMIZATION OF ELECTRIC TROLLEY LEAF SPRING USING RSM

Abstract

In current scenario, automotive sector is rapidly changing and exploring different fuels, materials and designs for better results. Weight of the suspension system which accounts 10-20 percent of total vehicle weight is one of these areas which need to be continuously explored for increasing mechanical efficiency of the vehicle. Various composites are already tested and evaluated to replace the traditional leaf spring for increasing performance of automotives. The present work deals with design, modeling and multi factor optimization of leaf spring with the help of Finite Element Method and Response Surface Methodology. Master leaf of electric trolley suspension system was considered for this research work and Carbon Fiber Reinforced Polymer (CFRP) composite is selected to replace the existing (SAE 5160) material. Total 9 models of CFRP material are analyzed and compared in terms of various parameters like Von misses stress, deformation, mass and fatigue life. FEM results are further utilized in Response Surface Methodology (RSM) technique to get optimized value for “width and thickness” of CFRP leaf spring. Modeling is done in ANSYS Workbench 2021 R1 software along with real situation boundary conditions and actual loading (considering factor of safety 2). Validation of FEM model is done with the help of analytic model calculation. After getting the optimized design through “Design Expert” software, it is observed that around 70-80% spring weight is reduced along with increase in fatigue life when CFRP optimized model is used.