Much decision making in the real world takes place in an environment in which the goals, constraints, and consequences of possible actions are not known precisely. The tools of fuzzy set theory can be used to deal with such imprecision in a quantitative manner. This use and effectiveness of fuzzy theories in the formulation and solution of design problems are developed and described herein through application to two types of helicopter design problems involving multiple objectives. The first problem deals with the determination of optimum flight parameters to accomplish a specified mission in the presence of three competing objectives. The second problem addresses the optimum design of the main rotor of a helicopter involving eight objective functions. The tools of fuzzy set theory have been used to model the vague and imprecise information in the formulation of these problems. A method for solving the resulting fuzzy multiobjective problem using nonlinear programming techniques is presented. Results obtained using fuzzy formulation are compared with those obtained using crisp optimization techniques.
ASJC Scopus subject areas
- Aerospace Engineering