WEIGHT OBJECTIVES STRATEGY IN MULTICRITERION FUZZY MECHANICAL AND STRUCTURAL OPTIMIZATION

The weighting strategy has received a great attention and has been wid ely applied to multicriterion optimization. This gaper examines a glob al criterion method (GCM) with the weighting objectives strategy in fu zzy structural engineering problems. Fuzziness of those problems are i n their design goals, constraints and variables. Most of the constrain ts are originated from analysis of engineering mechanics. The GCM is v erified to be equivalent to fuzzy goal programming via a truss design. Continued and mixed discrete variable spaces are presented and examin ed using a fuzzy global criterion method (FGCM). In the design process a weighting parameter with fuzzy information is introduced into the d esign and decision making. We use a uniform machine-tool spindle as an illustrative example in continuous design space. Fuzzy multicriterion Optimization in mixed design space is illustrated by the design of me chanical spring stacks. Results show that weighting strategy in FGCM c an generate both the best compromise solution and a set of Pareto solu tions in fuzzy environment. Weighting technique with fuzziness provide s a more relaxed design domain, which increases the satisfying degree of a compromise solution or improves the final design.