Multi-objective optimization for sheet metal formnig of drawing with successive response surface method

This paper describes a multi-objective optimization ofdrawbead geometrical parameters of automotive panel using successiveresponse surface method. The existing response surface method has a lowprecision in the entire design space, and conventional single-objectiveoptimization design does not provide for multi-objective conditions and hasbeen used to optimize only a single objective. The present method updatesthe region of interest (ROI) in the design space by panning and zooming. Ineach ROI, a set of pareto optimal solutions of equivalent drawbead restraintforce,are obtained to minimize the defects of crack and wrinkle by combiningdesign of experiments, successive response surface method andmulti-objective particle swarm optimization. Through the minimum distancemethod, a solution with best forming approach is obtained from the paretooptimal solutions, and it is used as the center point of the next region ofinterest. The optimal drawbead restraint force will be obtained by theiterative procedure. The optimal design geometric parameters of drawbead canbe obtained using the optimal drawbead restraint force and geneticalgorithm. These optimal parameters can be efficiently used to improve theforming properties of sheet. Numerical examples indicate that the presentmethod has higher precision and practicability compared with the existingtechniques.