This bachelor thesis was conducted in collaboration with Ecoist Cars and investigates the static structural performance of the chassis in their electric three-wheeled vehicle Tian. The study focuses on the midsection of the chassis, where static loads from the driver and passenger cause stress concentrations. A finite element analysis (FEA) was performed using both SolidWorks Simulation and SimSolid to evaluate the stress distribution, deformation, and structural integrity under load.

Two simulation models were analyzed: one based on the original weld layout and one with an optimized distribution of spot and seam welds. The optimized configuration reduced maximum displacement from 0.50 mm to 0.36 mm and decreased von Mises stress from approximately 160 MPa to 129 MPa, remaining safely below the yield strength of S235 steel. These results demonstrate improved load transfer and reduced peak stress without increased material usage.

The findings highlight the critical role of weld placement in achieving a structurally reliable and manufacturable chassis. The methodology and conclusions serve as a foundation for Ecoist Cars in their transition to production, and as a reference for future sustainable lightweight design.