フリーフォルム最適化手法を用いてバイブレーションルアー設計における基本的検討

抄録

Lure fishing is a kind of fishing methods that using fishing lures as artificial fish baits and has been more and more popular among the world. The vibration lure is the regular item among fishing lures, which performs vibration to bait fish. In the present work, to enhance the vibration behavior of vibration lure with a real analytical condition, we propose a free-form optimization method to for fundamental frequency maximization design problem considering solid structures under external loading, and carry out shape optimization for a metal vibration lure. We use the fundamental frequency (the 1st order) eigenvalue as the objective function and maximize it subject to a weight constraint. As the optimal results, the fundamental frequency of a vibration lure could be enhanced to 2.20 times as much as its initial value considering the external loading (i.e. the water pressure and tractive force of fishing line), while the mass of the optimal shape satisfied the mass constraint during the optimal design process. As a comparison, we also perform a design optimization of the vibration lure without considering the external loading, whose fundamental frequency can be also enhanced over 2 times as much as its initial value, and we conclude that the external loading only made a slight effect on the optimal results.