Performance Analysis in Disturbance on Initial Alignment of Laser Inertial Navigation System Using Unscented Kalman Filter

Oh, Juhyun

doi:2014.17.4.537

J. KIMS Technol > Volume 17(4); 2014 > Article

Journal of the Korea Institute of Military Science and Technology 2014;17(4):537-543.
DOI: https://doi.org/10.9766/KIMST.2014.17.4.537

Performance Analysis in Disturbance on Initial Alignment of Laser Inertial Navigation System Using Unscented Kalman Filter

Juhyun Oh

The 3rd Research and Development Institute, Agency for Defense Development

UKF를 적용한 레이저 관성항법장치의 외란에 대한 초기정렬 성능분석

오주현

국방과학연구소 제3기술연구본부

Abstract

RLG(Ring Laser Gyroscope) is a main device of LINS(Laser Inertial Navigation System). RLG has the lock-in region in which there is no output signal. To alleviate the lock-in problem, a mechanical oscillation, the dither motion, is applied on RLG. A LPF(Low Pass Filter) is usually used on the output of RLG and accelerometer to remove the noise that is made by the dither motion. When the LINS is induced the disturbance during the initial alignment, it takes more time on alignment due to the use of the LPF and a fixed gain controller. In this paper, an initial alignment using UKF(Unscented Kalman Filter) is designed and analysed. Analysis include comparison between conventional initial alignment loop using fixed gain type controller and proposed initial alignment using UKF. Moreover, Disturbance inducing test results are demonstrated.

Key Words: Laser Inertial Navigation System, Initial Alignment, Disturbance, Unscented Kalman Filter