基于小波包能量谱的航天器在轨泄漏漏孔形状辨识方法

Method for identifying the shape of spacecraft in-orbit leak hole based on wavelet packet energy spectrum

为了实现对航天器在轨泄漏漏孔形状的准确辨识,提出基于小波包能量谱和支持向量机的航天器在轨泄漏辨识方法。首先分析圆形、长方形、正三角形3种典型形状漏孔之泄漏信号的频域特点,之后运用小波包能量谱提取不同形状漏孔泄漏信号的特征值,最后运用提取的特征值配合支持向量机建立辨识模型,实现对漏孔具体形状的辨识。对该辨识方法进行试验验证,将3种形状的漏孔分为A、B两组,利用A组漏孔进行泄漏信号特征值提取与辨识模型的训练,再对B组漏孔进行辨识准确率测试;结果表明该方法可以实现对不同形状漏孔的辨识,在合适的小波包分解层数下,总体辨识准确率可达95.9%。

In order to accurately identify the shape of the leaks for the in-orbit spacecraft, we propose a method based on the wavelet packet energy spectrums and the support vector machine. In this paper, firstly, the characteristics of the frequency spectrum of the holes of three typical shapes, namely, the circle, the rectangle and the equilateral triangle, are analyzed, respectively. Then the wavelet packet energy spectrum is used to extract the characteristic values of the leakage signals from different leaks. Finally, these characteristic values and the support vector machine are integrated to build a model for identifying the shape of the leaks. Experiments are carried out to validate the above method, leaks of different shapes are divided into the group A and the group B,where the group A is for training the identification model, and the group B is for testing the model. By this method, a total identification accuracy of 95.9% can be reached eventually with a proper number of decomposition layers.