Application of the preference selection index method in multi-objective lightweight design of heavy commercial vehicle frames

An optimization strategy integrating contribution analysis, design of experiment, an approximate model and a preference selection index (PSI) method is proposed to establish an efficient multi-objective lightweight design approach for heavy commercial vehicle frames. First, finite element and rigid–flexible coupling virtual prototype models are established and their accuracy is verified using experiments. Secondly, the fatigue life of the frame is calculated using the power spectral density function, frequency response function and corrected stress–life curve. Finally, the thicknesses of frame components are regarded as design variables, and the mass and maximum root mean square stress are considered as design objectives in the process of lightweight design. Three optimization strategies are used to investigate the characteristics of the PSI method. The results showed that the optimization strategy combined with the PSI method demonstrates high computational efficiency and reliability.