A Fuzzy Interactive Method for Multiobjective Engineering Design Problems

Engineering design is a process of formulating a plan for the satisfaction of human needs through a cycle of steps that include problem definition, conceptualization, embodiment, and detailing. Conflicts always exist in engineering design process. Generally these problems are multiobjective and non-linear in nature. To solve these multiobjective problems, which are conflicting and non-linear, a fuzzy interactive method is introduced. In this method, firstly each objective is represented as a fuzzy goal using triangular or trapezoidal fuzzy number, and then product operator is used to aggregate these fuzzy goals. Moreover, to direct the search at each interactive phase, the decision maker gives his/her minimum reservation level for each objective which is used as additional constraint in the problem. Finally, a real coded genetic algorithm, MI-LXPM, is used to find the solution of the resultant fuzzy optimization problem. Gear box design and simply supported beam design problems are solved using proposed interactive method.