Application of fuzzy theories to multiple objective decision making in system design

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. To deal with such imprecision in a quantitative manner, the tools of fuzzy set theory can be advantageously applied. The use and effectiveness of fuzzy theories in the formulation and solution of design problems are developed and described via an application in the engineering design of high speed mechanisms. An integrated approach to the design of high speed planar mechanisms is formulated as a multiple objective nonlinear programming problem, which combines both the kinematic and dynamic synthesis aspects of mechanism design. To model the vague and imprecise information in the problem formulation, the tools of fuzzy set theory have been used. A novel method of solving the resulting fuzzy multiple objective problem using mathematical programming techniques is presented. The outlined procedure should be useful in engineering and management design situations where uncertainty or ambiguity arises about the preciseness of permissible parameters, degree of credibility, and correctness of statements and judgements.