EMD滤波在捷联惯导晃动基座初始对准中的应用

Research on the Application of EMD Filter in Initial Alignment of SINS on Swaying Base

关键词:  初始对准  晃动基座  经验模态分解法  凝固惯性系

Key words:  Initial alignment  Swaying base  Empirical mode decomposition method  Inertial fixed frame

摘要:

为了实现晃动基座情况下光纤捷联惯性导航系统的高精度初始对准，提出了一种基于经验模态分解（EMD）法去噪的抗干扰初始对准算法。该算法在凝固惯性系下进行姿态更新，以反映载体在晃动干扰下的姿态变化，从而消除角运动干扰的影响；并针对EMD法的不足对其进行改进，然后对加速度计的输出进行去噪，以消除线运动干扰的影响。结果表明：改进后的EMD法具有良好的去噪效果，基于EMD法去噪的抗干扰初始对准算法具有角运动和线运动的干扰抑制能力，能够实现晃动基座下的高精度抗干扰初始对准。

Abstract:

In order to realize the high precision initial alignment of FOG SINS on swaying base, an anti-interference initial alignment algorithm based on empirical mode decomposition (EMD) denoise method is presented. The algorithm updates attitude in inertial fixed frame to reflect the attitude change of the carrier under swaying interference to isolate the influence of angular motion interference. Aiming at the deficiency of EMD method, improvements of it are made and the output of the accelerometer is denoised to reduce the influence of linear motion interference. The results show that the improved EMD method has good denoising effect. The anti-interference initial alignment algorithm based on EMD denoise method can realize the alignment quickly and accu-rately on swaying base in the presence of angular motion and linear motion interference.