The Mind Process of Design Learned from the Revolving Door Accident

In March, 2004, a boy ran into an automatic revolving door, jammed his head and was killed at a skyscraper in Roppongi, Tokyo. Yotaro Hatamura, as a citizen, formed and executed a project to uncover the danger associated with “doors” and to develop a guideline for their safety. The project led to a design theory whose necessity had not been recognized to the extent it deserved. This paper reports our findings from the project about doors. The knowledge we gained through studying the cause of the accident applies to a wide range of technology in general.