Static Analysis on a Roll Cage Frame for an Off-Road Vehicle

The objective of this research is to design and analyze a roll cage structure for an off-road vehicle that was used for SAE Baja competition by UNLV SAE Baja team. Baja SAE is an intercollegiate competition to design, fabricate, and race a small, single passenger, off-road vehicle powered by a 10 HP Briggs Stratton 4-Stroke gasoline engine. Since the off-road vehicle is powered by a small capacity engine, the weight of the structure is very critical and must be optimized to improve the performance of the vehicle. In an effort to optimize the structure, a finite element analysis (FEA) was performed and the effects of stress and deformation were studied for a linear static frontal impact analysis on roll cage structure. The frame was further modified for structural rigidity. Additional strengthening gussets were added at the locations of high stresses to reduce the stress concentration. Further analysis was carried out to study the influence of other auxiliary structures attached to the frame such as the engine mount, transmission and other components of the vehicle. The design of the structure was considered safe when the Von-Mises stresses were less than the yield strength of the material and the deflections of the structural members were favorable enough for the safety of the driver.