Gait-Event Detection using an Accelerometer for the Paralyzed Patients

가속도계를 이용한 마비환자의 보행이벤트 검출

  • 공세진 (건국대 의료생명대 의학공학부) ;
  • 김철승 (건국대 의료생명대 의학공학부) ;
  • 문기욱 (건국대 의료생명대 의학공학부) ;
  • 엄광문 (건국대 의료생명대 의학공학부) ;
  • 탁계래 (건국대 의료생명대 의학공학부) ;
  • 김경섭 (건국대 의료생명대 의학공학부) ;
  • 이정환 (건국대 의료생명대 의학공학부) ;
  • 이영희 (연세대 원주의과대 재활의학교실)
  • Published : 2007.05.01


The purpose of this study is to develop a practical gait-event detection system which is necessary for the FES (functional electrical stimulation) control of locomotion in paralyzed patients. The system is comprised of a sensor board and an event recognition algorithm. We focused on the practicality improvement of the system through 1) using accelerometer to get the angle of shank and dispensing with the foot-switches having limitation in indoor or barefoot usage and 2) using a rule-base instead of threshold to determine the heel-off/heel-strike events corresponding the stimulation on/off timing. The sensor signals are transmitted through RF communication and gait-events was detected using the peaks in shank angle. The system could detect two critical gait-events in all five paralyzed patients. The standard deviation of the gait events time from the peaks were smaller when 1.5Hz cutoff frequency was used in the derivation of the shank angle from the acceleration signals.


gait-events;FES;rule-base;shank angle;accelerometer


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