Multi-objective reliability based design optimization and risk analysis of motorcycle frame with strength based failure limit

Motorcycle industry is growing at very fast pace and presently have largest market share of vehicles in India due to the price and mileage centric decision of the consumers. Among the vehicles met with accidents, two wheeler's contribution is highest. A lot a research have been carried out on chassis of cars, but a limited research is reported on two wheelers. Hence a study on motorcycle frame is considered in this work to study stress distribution in frame under impact load. An approach using response surface method is proposed to optimize the motorcycle frame where the objective is to reduce frame mass and minimize the maximum structural stress under impact load for maximum reliability. Reliability analysis of the frame is performed with respect to limit state of strength. The design variables of interest are diameter and thickness of two crucial members at the front end and material of the frame. Finite element method was used to carry out the modeling and analysis of the frame. Results of simulation are validated by conducting experiments on a practical setup. The output of this work is the dimensions of the frame which minimizes the mass and minimizes the maximum structural stress for different levels of reliability. Risk analysis of the frame is performed to quantify the risk associated with different levels of stress. © 2012 The Society for Reliability Engineering, Quality and Operations Management (SREQOM), India and The Division of Operation and Maintenance, Lulea University of Technology, Sweden.