Optimal Electrode Selection for Detection of Human Leg Movement Using Bio-Impedance

생체 임피던스를 이용한 인체 하지운동 출을 위한 최적 전극위치 선정

  • 송철규 (전북대 전자정보공학부) ;
  • 윤대영 (전북대 대학원 메카트로닉스학과) ;
  • 이동헌 (전북대 과학기술학부) ;
  • 김승찬 (연세대 의대 의학공학교실) ;
  • 김덕원 (연세대 의대 의학공학교실)
  • Published : 2003.08.01

Abstract

This paper describes the possibility of analyzing gait pattern from the changes of the lower leg electrical impedance. This impedance was measured by the four-electrode method. Two current electrodes were applied to the thigh, knee, and foot., and two potential electrodes were applied to the lateral, medial, and posterior position of human leg. The correlation coefficients of the joint angle and the impedance change from human leg movement was obtained using a electrogoniometer and 4ch impedance measurement system developed in this study. We found the optimal electrode position for knee and ankle joint movements based on high correlation coefficient, least interference, and maximum magnitude of impedance change. The correlation coefficients of the ankle, knee, and the hip movements were -0.913, 0.984 and 0.823, respectively. From such features of the human leg impedance, it has been made clear that different movement patterns exhibit different impedance patterns and impedance level. This system showed feasibility that lower leg movement could be easily measured by impedance measurement system with a few skin-electrodes.

Keywords

References

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