Abstract:

A modified Particle Swarm Optimization (PSO) algorithm was built based on stagnation judging criterion and particle velocity updating equation to improve the diversity of particles during optimization procedure. A new velocity updating equations was activated to improve the diversity between particles while the particles optimization procedure fell into stagnation. The modified PSO algorithm was compared with the standard version of PSO based on a set of benchmark functions by mathematical experiments. Auto body lightweight optimization design was made by using the modified PSO incorporated with metamodeling technique and reasonable constrained handling method, considering 100% frontal impact, 40% frontal offset impact, side impact, rear impact and roof crash conditions, and under the premise of satisfying each structural performance index. The results show that the optimization solutions by modified PSO algorithm are superior to those by standard PSO with areduced mass of 23.41 kg. This will provide a referential method for light mass design of auto-body.

Key words: design of auto-body, lightweight, multiple impact conditions, particle swarm optimization (PSO), stagnation judging criterion , metamodeling