Abstract
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.