Step Counts and Posture Monitoring System using Insole Type Textile Capacitive Pressure Sensor for Smart Gait Analysis

깔창 형태의 전기용량성 섬유압력센서를 이용한 보행 횟수 검출 및 자세 모니터링 시스템

  • Received : 2012.07.28
  • Accepted : 2012.08.14
  • Published : 2012.08.31


We have developed a textile capacitive pressure sensor for smart gait analysis. The proposed system can convert sensor signal into step counts and pressure levels by different posture. To evaluate the performance of insole type textile capacitive sensor, we measured capacitance change by increment of weights from 10 kg to 100 kg with 10 kg increment using M1 class rectangular weights (four 20 kg weights and two 10 kg weights) which have ${\pm}10%$ tolerance. The result showed non-linearity characteristic of a general capacitive pressure sensor. The test was performed according to a test protocol for four different postures (sitting, standing, standing on a left leg and standing on a right leg) and different walking speeds (1 km/h and 4 km/h). Five healthy male subjects were participated in each test. As we expected, the pressure level was changed by pressure distribution according to posture. Also, developed textile pressure sensor showed higher recognition rate (average 98.06 %) than commercial pedometer at all walking speed. Therefore, the proposed step counts and posture monitoring system using conductive textile capacitive pressure sensor proved to be a reliable and useful tool for monitoring gait parameters.


Gait;Step Count;Posture;Conductive Textile;Textile Capacitive Pressure Sensor


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