1. Graduate School of Design, Kyushu University, Fukuoka 815-8540, Japan
2. Faculty of Science and Engineering, Saga University, Saga 840-8502, Japan
3. Faculty of Design, Kyushu University, Fukuoka 815-8540, Japan
4. Faculty of Rehabilitation, Hiroshima International University, Higashihiroshima 739-2631, Japan