Abstract: Fuzzy evaluation theory is used to calculate the module planning principles based on the analysis of parts function and physical quality, and the multiobjective module planning optimization model is constructed. In view of the problem of traditional objective weighted method, an improved strength Pareto evolutionary algorithm (SPEA2+) is employed to optimize multi-objective module. As a result, a serial of module planning schemes are presented in the form of Pareto optimal set. Moreover, an approach based on fuzzy set theory is developed to extract one of the Pareto-optimal solutions as the best compromise one. A living example related with a project in the sewing machine industry is given to prove the feasibility and validity of the method.

Key words: Clustering degree, Degree of coupling, Module planning, Multiobjective optimization, Pareto set, Strength Pareto evolutionary algorithm, Cold rolling, Mathematical model, Roughness, Surface topography, Textured work rolls