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A Study on vertical mode system identification for a single tilt wing UAV

단일 틸트윙 방식 무인기의 수직모드 시스템 식별 기법 연구

  • Received : 2014.04.25
  • Accepted : 2014.10.28
  • Published : 2014.11.01

Abstract

This paper presents system identification of a single tilt wing UAV. A Modified Equation Error Method(MEEM) and Extended Kalman Filter(EKF) are used for the identification of a single tilt wing UAV system in frequency-domain and time-domain, respectively. Simulated flight data is obtained from CNUX-3's vertical mode linear simulation with realistic sensor noise. System identification performance is analyzed with respect to a variety of design parameters of the MEEM. Also, High accuracy Fourier Transform(HFT) is applied to enhance the performance of MEEM. The results of the MEEM is compared with those of the EKF. Design parameters of the MEEM and initial conditions of the EKF are decided from optimization.

본 논문에서는 단일 틸트윙 무인기의 시스템 식별기법과 결과를 제시하였다. 주파수 영역의 시스템 식별 기법인 Modified Equation Error Method(MEEM)와 시간 영역의 시스템 식별 기법인 확장 칼만 필터(Extended Kalman Filter, EKF)를 사용하였다. 시스템 식별 기법의 검증을 위해 단일 틸트윙 방식 무인기인 CNUX-3의 모델을 통해 획득한 수직모드의 선형 시뮬레이션 결과에 센서 특성을 반영한 노이즈를 합성하여 가상의 비행데이터를 생성했다. 설계 변수의 변화에 따른 MEEM의 시스템 식별 성능 변화를 분석하였다. 또한 고정밀 푸리에 변환(High accuracy Fourier Transform)을 MEEM에 적용하여 정확도를 향상시켰다. MEEM과 EKF의 시스템 식별 결과를 비교하고, 최상의 성능지수를 갖는 설계 변수값과 초기값을 최적화를 통해 결정하였다.

Keywords

References

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