Improvement of Crash Worthiness of Structure of Three Wheeler Vehicle

Abstract

Three wheeled motor vehicles, popularly termed as auto rickshaws or Bajaj, are gaining popularity in the commuting world due to the driving conditions prevailing all over the world. With the increase in traffic every year, the number of road accident injury risk and deaths by type of vehicles (percentage share), of which three-wheeler accidents contributes is increasing. These vehicles haven’t subjected to any crash safety specifications and are not evaluated for crash worthiness. So, it is now time to consider safety features/modification of three-wheelers to reduce the grave consequences of its users. Improvements should be made on the structure of TWV in order to improve the structure strength, stability, crashworthiness, safety etc. This thesis work was aimed to improve the crashworthiness of the existing three-wheeled to minimize crash injuries. The frontal, side, rollover and rear impact collision of the existing TWV analyzed. Human dummies are incorporated in the analysis to study the response of occupants at event of crushes. Based on the analysis results obtained from the existing model of TWV then modifications are made by means of a stable frame structure, energy absorbing components and a restraint system. Then the modified TWV was analyzed under the same condition as the existing one. Software like that of CATIA was used for 3d modeling and LS-DYNA for simulation and FEM analysis. The result of the simulations shows that with the modification, 80mm more living space, 630 N reduction of impact force, and 0.8 kJ of additional energy is absorbed during side collision. The rear structure of the modified model also provided 30% more protection for rear parts. In addition, the energy absorption at the rear is increased with 1.6 kJ of energy. Moreover, the force of impact was also reduced by 22%. On another hand, during the front crush, the existing model proved better performance in terms of energy absorption and impact force. Since for the modified model, the structural deformation is less and occupants were fitted with lap belts, so the disadvantage of low absorption and high impact force during frontal crush was overcome. So it can be concluded that with the modified model, The safety and crashworthiness of the TWV was greatly improved without affecting the appearance and weight of the existing models. In addition, the safety and rate of death of passengers on the existing three-wheeler vehicles are reduced. so that the existing model of TWV should be fitted with the designed crashworthiness futures implemented on this paper