應用遺傳演算法於耐衝擊結構拓樸最佳化

Topology Optimization of Structure for Impact Resistance Using Genetic Algorithm

林家暉(Chia-huei Lin)

指導教授 ： 吳俊瑩

大同大學/工程學院/機械工程學系所/碩士(2005年)

摘要

為提高辦事的效率，符合現代人們生活的方便性以及行動性，對於行動電子產品的需求越來越大，同時對於行動電子產品的要求也越來越高。不論是筆記型電腦、PDA、行動電話、MP3播放機、行動碟等，不但要求產品要輕薄短小，同時要能夠耐摔落或防水，以彌補實際生活上人們會不小心犯錯對產品功能所造成的的影響。為保護產品功能正常不損壞及產品品質，如何建構一個設計系統的架構，能夠輔助對各種需要耐衝擊的結構，如何在有限材料的使用條件內設計出輕、薄又耐摔的產品結構成為絕對重要的課題。

本研究的主要是利用電腦輔助工程分析軟體ANSYS/LS-DYNA為分析工具，以進行各種結構受衝擊負荷下的工程分析，然後以自行發展的遺傳演算法最佳化程式整合ANSYS/LS-DYNA進行耐衝擊結構多值域拓樸最佳化設計，以尋找輕又耐衝擊的結構。首先以測試函數驗證遺傳演算法最佳化程式的效能與正確性，接著以靜態驗證自行開發的程式在結構拓樸最佳化設計方面應用效能。最後整合遺傳演算法程式及ANSYS/LS-DYNA於耐衝擊結構的拓樸最佳化設計，尋找輕且耐衝擊的結構設計。

關鍵字

衝擊 ； 耐衝擊 ； 最佳化 ； 拓樸 ； 遺傳演算法

並列摘要

In order to improve the efficiency of processing affairs and fit the requirements of convenience and mobility of daily life，the demand for portable electronic products was increased dramatically. The specification for portable electronic products also became higher. The products, like notebook computer, PDA, cellular phone, MP3 player and mobile disk, were asked to be light、thin and small. They also should be drop resistance and waterproof to avoid malfunction caused by careless incident in our daily life. The weight became lighter and the thickness of case became thinner are the consistent requirements for portable electronic products. In order to protect quality of product, it is very important to construct a design system to support engineer with an effective design for different requirements. Designing structure with requirements of light、thin and impact resistance to avoid malfunction become an absolute important topic for portable electronic products.

In this study the commercial computer-aided engineering software ANSYS/LS-DYNA will be used as the tool for analysis of different impact loading for structure. A genetic algorithm based optimization program will be integrated with ANSYS/LS-DYNA for multi-modal optimization for light and impact resistance structure. Some test functions were used to verify the correctness and performance of genetic algorithm optimization first. Then structure subjected static loadings was utilized to illustrate the application of the developed GA program in topology optimization of structure. Finally the integration system of genetic optimization program with ANSYS/LS-DYNA was applied to search structural topology for light and impact resistance.

並列關鍵字

Genetic Algorithm ； Impact ； Impact Resistance ； Optimization ； Topology

參考文獻

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