基于自适应滤波的天文惯性组合导航技术

Application of CNS-INS Integrated Navigation Technology Based on Adaptive Filtering

以天文测星获取的Psai角为量测信息进行天文惯性组合导航时,Psai角由天文测星高度差经二阶矩计算而来,故Psai量测信息噪声统计特性不再服从高斯分布,对天文惯性组合导航效果产生消极影响。针对上述问题,提出基于自适应滤波的天文惯性组合导航技术,通过对量测噪声协方差矩阵采用自适应加权调整方法,降低噪声非高斯特性对组合导航误差抑制效果影响。基于天文惯性组合导航设备试验数据,对比Psai角量测噪声高斯近似和自适应处理两种方法下的组合导航位置误差抑制效果。试验表明:Psai角量测噪声自适应滤波处理比高斯近似具有更好的位置误差抑制效果。因此,应用基于自适应滤波的天文惯性组合导航技术对惯导误差估计有较好效果,有利于天文惯性组合导航技术的工程应用推广。

The Psai angle is calculated based on the second-order moment of the height difference obtained from astronomical measurements,when using the Psai angle obtained from astronomical measurements as measurement information for celestial-inertial integrated navigation.Therefore,the statistical characteristics of the Psai measurement noise no longer follow a Gaussian distribution,which has negative effects in the performance of celestial-inertial integrated navigation.To address this issue,an adaptive filtering-based celestial-inertial integrated navigation technology is proposed,using an adaptive weighted adjustment method to adjust the covariance matrix of the measurement noise,the impact of non-Gaussian characteristics of noise on the error suppression effect of integrated navigation is reduced.Based on experimental data from celestial-inertial integrated navigation equipment,the error suppression effect of integrated navigation position under two methods,namely Gaussian approximation and adaptive filtering of Psai angle measurement noise,is compared.The experiment indicates the adaptive filtering method for Psai angle measurement noise has a better position error suppression effect than the Gaussian approximation method.Therefore,the application of adaptive filtering-based celestial-inertial integrated navigation technology has a more favorable effect on inertial error estimation and is beneficial to the engineering application and promotion of celestial-inertial integrated navigation technology.