Journal of Advanced Navigation Technology (한국항행학회논문지)

The Korean Navigation Institute (한국항행학회)
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Improvement of Strain Detection Accuracy of Aircraft FBG Sensors Using Stationary Wavelet Transform

정상 웨이블릿 변환을 이용한 항공기 FBG 센서의 변형률 탐지 정확도 향상

  • 손영준 (한서대학교 대학원 항공시스템공학과) ;
  • 신현성 ((주)유콘시스템) ;
  • 홍교영 (한서대학교 항공전자공학과)
  • Received : 2019.08.06
  • Accepted : 2019.08.25
  • Published : 2019.08.30
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Abstract

There are many studies that use structure health monitoring to reduce maintenance costs for aircraft and to increase aircraft utilization. Many studies on FBG sensors are also being conducted. However, if the FBG sensor is installed inside the composite, voids will occur between the layers of the composite, resulting in signal split problem. In addition, the FBG sensor is not affected by electromagnetic waves, but will produce electromagnetic noise caused by electronic equipment during post-processing. In this paper, to reduce the error caused by these noises, the stationary wavelet transform, which has the characteristics of movement immutability and is efficient in nonlinear signal analysis, is presented. And in the above situation, we found that noise rejection performance of stationary wavelet transform was better compared with the wavelet packet transform.

구조 건전성 모니터링 기술을 이용하여 항공기의 유지 보수 비용을 줄이고 항공기의 가동률을 높이고자 하는 많은 연구가 진행되고 있다. 이에 FBG 센서에 대한 많은 연구가 함께 진행되고 있다. 하지만 복합재 내부에 FBG 센서를 설치할 경우, 복합재 층 사이에 보이드(void)가 발생하게 되고 이로 인해 신호 갈라짐 (split problem)이 발생하게 된다. 또한, FBG 센서는 전자기파에 영향을 받지 않지만, 후속처리 과정에서 사용되는 전자장비에 의한 전자기파 잡음이 발생하게 된다. 본 논문에서는 이러한 잡음으로 인한 오차를 줄이기 위해 이동 불변의 특성을 지니고 비선형적인 신호분석에 효율적인 정상 웨이블릿 변환 기법을 제시하였다. 그리고 위의 상황에서 웨이블릿 패킷 변환과 비교하였을 경우 정상 웨이블릿 변환의 잡음 제거 성능이 더 우수한 것을 확인하였다.

Keywords

References

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