Correlation between the Displacement of Center of Gravity and Lyapunov Exponent during Treadmill Walking

트레드밀 보행에서 무게중심 이동과 리아프노프 지수 사이의 상관관계

  • Kim, Soo-Han (School of Mechanical Engineering, Pusan Univ.) ;
  • Park, Jung-Hong (School of Mechanical Engineering, Pusan Univ.) ;
  • Son, Kwon (School of Mechanical Engineering, Pusan Univ.)
  • 김수한 (부산대학교 기계설계대학원) ;
  • 박정홍 (부산대학교 기계공학부) ;
  • 손권 (부산대학교 기계공학부)
  • Published : 2010.02.01

Abstract

The purpose of study is to investigate the correlation between the Lyapunov exponent (LE) and the displacement of the center of gravity (DCG) for clarifying walking stability on the treadmill. From fifteen young healthy subjects volunteered, lower extremity joint angles were recorded using a three-dimensional motion capture system with reflective markers. The anteroposterior DCG and the LE were calculated by a commercial software. A linear correlation between LE and DCG (p<0.05) showed that LEs compensated for walking distance on the treadmill walking. However, LEs were found to be independent of self-selected walking speeds by a negligible correlation between LE and the Froude number (p>0.05).

Keywords

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