K. Hamada, M. Kitamura, Yoshifumi Takanobu
Journal name not available for this finding
Decision of principal particulars is the first stage of ship design. This stage is an important stage where essential information of the ship is decided and the influence on the cost and the performance is extremely large. However, various kinds of analyses which contain the error margin are used because detailed information on the ship is not available. Therefore, re-design and the deterioration of the performance occur although the margins on weight and so on are considered. The purpose of this study is to propose the design support system for considering the errors by using the robust optimization. The robust optimization is an optimization technique in which the influence of the error of the design variable is considered. However, the error margin of an analysis method is larger than the error margin of the design variable in the design of principal particulars. In order to solve this problem, new robust optimization technique to consider the error of an analysis is proposed. The characteristics of the proposed method are following points: 1) Input information and output information of analysis are defined as not a fixed value but an indeterminate value, that is, expected value and standard deviation. The error margin of preceding analytical technique is treated as an error margin of input information on the next analysis. 2) Expected value of the output is approximated to the output value without errors. 3) Standard deviation of output information is calculated by using the theory of spread of the error. 4) The accumulation of the error margin is calculated by repeating the above-mentioned process. Some examples using the proposed method are shown in the paper and these are compared with the solutions of present technique. As a result, the possibility of the improvement of the design is shown.