由於環保意識抬頭,各國紛紛制定環保限制指令,輸入之產品必須經由生命週期評估,確保達到相關規定,對於產品開發帶來極大的衝擊。現今產品大多於量產階段,才進行生命週期評估,對於不符合法規的結果,僅能以設計變更方式進行補救,能改善的部分相當有限,應提早於設計階段考量環境衝擊。以往的相關研究,缺乏嚴謹的定量分析方法。有鑑於此,本研究提出創新性產品結構變異方式,發展在設計階段對於環境衝擊的量化評估方法論,藉此提升產品開發的整體效率。利用零件特徵定義方式,進行零件功能、製造、組裝及合併的產品結構分析,並結合Solid WorksTM電腦輔助設計軟體,進行產品結構上幾何及物理性質合理判斷。以環境衝擊指標作為目標,透過基因演算法計算零件組合、禁忌搜尋法規劃組裝順序,以及動態規劃做供應商選擇,自動求得對應最佳品結構設計。可同時評估生命週期中,產品原物料開採、製造與組裝能源消耗與產品運輸等環境衝擊。研究內容引用國內生命週期評估資料庫,首次針對本土資料進行量化分析,可作為同時考量產品設計及環境衝擊之最佳化產品結構的決策依據,實現永續設計的概念。
Many countries have enforced environmental protection directives due to the recent awareness of environmental issues. They require the products imported have to comply with the directives by lifecycle assessment. This results in a huge impact on product development. Currently most products perform lifecycle assessment at the production/manufacturing stage. Any problems discovered so late can only be corrected through engineering changes, which involve high cost but low efficiency. The assessment needs to be conducted at early stages of a product lifecycle. However, previous studies failed to offer rigorous or quantitative methods on this matter. Thus, this research proposes a systematic method that reduces the environmental impact in the system design stage based on automatic variation of product structure. Product structure is optimized with the objective as minimization of CO2 emission of the entire product development process. CAD technologies are integrated for automatic product assembly and interference check of assembly process. Genetic Algorithms are applied to optimize selection of components while maintaining the product design functions. The assembly sequence is determined by Tabu search. Dynamic programming techniques are employed to choose suppliers. The results are combined to obtain optimal product structure design in consideration of CO2 emission during three major phases of a product life cycle: raw material production, assembly/manufacturing, and transportation. This work is the first study that utilizes domestic LCA data for quantitative analysis of the environmental impact during product development. It realizes the concept of sustainable design using actual data. The proposed method works as a decision-making tool in product design for reducing environmental impact.