UKF를 사용하는 SDINS의 운항 중 정렬

학위논문(석사)--서울대학교 대학원 :기계항공공학부,2006.Maste

In-flight Alignment Algorithm Using UKF

In this paper, GPS aided in-flight alignment algorithm using UKF is presented for an SDINS under large initial heading error. Usually, the EKF is applied for this task. However, the EKF is suboptimal choice from a theoretical point of view, as it approximates the propagation of mean and covariance of Gaussian random vectors through these nonlinear models by a linear transformation, which is accurate to first-order only. But UKF algorithms achieve an accurate approximation to at least second-order. Simulation results show that performance of EKF and UKF are the almost same when the initial heading error is small (about 30°) but UKF has a better performance for large initial heading error (about 45°).AD

Performance Analysis of In-Flight Alignment Using UKF

In this paper, in-flight alignment algorithm using UKF is presented for an SDiNS aided by SSBL or GPS system under large initial heading error. The EKF usually applied for this task. This approximates the propagation of mean and covariance accurate to first-order only. To overcome this limitation, the unscented transformation that achieves second order approximation is applied to the in-flight alignment. To analyze the performance of the proposed method, simulations for S-type trajectory are carried out. The results show that performance of EKF and UKF are the almost same when the initial heading error is smaller than 30°, but UKF has a better performance for large initial heading error about 45°.본 연구는 국방과학연구소와 두산인프라코어의 부분적인 지원에 의하여 수행되었음

Performance Analysis of In-flight Alignment Using UKF for Trajectory

In this paper, GPS aided in-flight alignment algorithm using UKF(Unscented Kalman Filter) is presented for an SDINS under large initial heading error and different trajectory. For this task, the EKF that approximates the propagation of mean and covariance accurate to first-order only is generally used. To overcome the EKF limitation, the various unscented transformations that achieve second order approximation are applied to the in-flight alignment. With a low cost MEMS IMU, the simulations are carried out at S-type and Circle-type trajectory for analyzing the performance of the proposed method. The results show that performance of UKF has a better than EKF for large initial heading error. And using S-type trajectory increase the performance of error estimates