【Special Issues:Ecodesign】
Design Methodology for Upgradable Products
Yasushi Umeda* and Shinsuke Kondoh*
* Department of Mechanical Engineering, Graduate School of Engineering, Tokyo Metropolitan University

† Correspondence should be addressed to Yasushi Umeda:
（Minami-Osawa 1-1, Hachioji, Tokyo, 192-0397 Japan）

Abstract
An major part of eco-design is looking at the product from the viewpoint of its full lifecycle, and designing for stability and reduction of overall waste. With regard to life time value, there are only two solutions; dematerialization and upgrading. This paper first discusses the role of upgrading in eco-design and introduces basic design ideas for upgradability. For example, “function independent production” and “function insensitive production” are two of the upgrading operations introduced in the paper. “Delay decision” and “enlarging/shrinking platform” strategies for compensating future uncertainty, the largest obstacle in designing for upgradability, are also presented. Finally, the upgrading design of a vacuum cleaner is illustrated as a case study.

Key words: upgrade, eco-design, 3R, value lifetime, design methodology