为减小光纤陀螺随机漂移,采用时间序列分析法对其进行ARMA模型辨识.提出一种全局最优的模型阶次搜索算法,将模型适用性检验方法中的BIC(Bayesian information criterion)用于模型阶次搜索,并采用Pandit-Wu建模思想,把二维搜索化为一维搜...为减小光纤陀螺随机漂移,采用时间序列分析法对其进行ARMA模型辨识.提出一种全局最优的模型阶次搜索算法,将模型适用性检验方法中的BIC(Bayesian information criterion)用于模型阶次搜索,并采用Pandit-Wu建模思想,把二维搜索化为一维搜索,得到了模型阶次的一致性估计.提出了一种改进的U-C算法,并与长自回归模型计算残差法相结合共同估计模型参数.它将非线性参数估计过程转化为线性过程,使用了正置与逆置漂移时序参与估计,以前向和后向模型的滤波误差平方和最小为参数估计的指标,在p+1维空间中求极小值.采用上述方法确定的模型其残差标准差为0.0024°,最大预报误差为0.0112°,能准确预报光纤陀螺随机漂移趋势.展开更多
A novel neural network based on iterated unscented Kalman filter (IUKF) algorithm is established to model and com- pensate for the fiber optic gyro (FOG) bias drift caused by temperature. In the network, FOG tempe...A novel neural network based on iterated unscented Kalman filter (IUKF) algorithm is established to model and com- pensate for the fiber optic gyro (FOG) bias drift caused by temperature. In the network, FOG temperature and its gradient are set as input and the FOG bias drift is set as the expected output. A 2-5-1 network trained with IUKF algorithm is established. The IUKF algorithm is developed on the basis of the unscented Kalman filter (UKF). The weight and bias vectors of the hidden layer are set as the state of the UKF and its process and measurement equations are deduced according to the network architecture. To solve the unavoidable estimation deviation of the mean and covariance of the states in the UKF algorithm, iterative computation is introduced into the UKF after the measurement update. While the measure- ment noise R is extended into the state vectors before iteration in order to meet the statistic orthogonality of estimate and mea- surement noise. The IUKF algorithm can provide the optimized estimation for the neural network because of its state expansion and iteration. Temperature rise (-20-20℃) and drop (70-20℃) tests for FOG are carried out in an attemperator. The temperature drift model is built with neural network, and it is trained respectively with BP, UKF and IUKF algorithms. The results prove that the proposed model has higher precision compared with the back- propagation (BP) and UKF network models.展开更多
文摘为减小光纤陀螺随机漂移,采用时间序列分析法对其进行ARMA模型辨识.提出一种全局最优的模型阶次搜索算法,将模型适用性检验方法中的BIC(Bayesian information criterion)用于模型阶次搜索,并采用Pandit-Wu建模思想,把二维搜索化为一维搜索,得到了模型阶次的一致性估计.提出了一种改进的U-C算法,并与长自回归模型计算残差法相结合共同估计模型参数.它将非线性参数估计过程转化为线性过程,使用了正置与逆置漂移时序参与估计,以前向和后向模型的滤波误差平方和最小为参数估计的指标,在p+1维空间中求极小值.采用上述方法确定的模型其残差标准差为0.0024°,最大预报误差为0.0112°,能准确预报光纤陀螺随机漂移趋势.
基金supported by the National Natural Science Foundation of China(6110418440904018)+3 种基金the National Key Scientific Instrument and Equipment Development Project(2011YQ12004502)the Research Foundation of General Armament Department(201300000008)the Doctor Innovation Fund of Naval University of Engineering(HGBSCXJJ2011008)the Youth Natural Science Foundation of Naval University of Engineering(HGDQNJJ12028)
文摘A novel neural network based on iterated unscented Kalman filter (IUKF) algorithm is established to model and com- pensate for the fiber optic gyro (FOG) bias drift caused by temperature. In the network, FOG temperature and its gradient are set as input and the FOG bias drift is set as the expected output. A 2-5-1 network trained with IUKF algorithm is established. The IUKF algorithm is developed on the basis of the unscented Kalman filter (UKF). The weight and bias vectors of the hidden layer are set as the state of the UKF and its process and measurement equations are deduced according to the network architecture. To solve the unavoidable estimation deviation of the mean and covariance of the states in the UKF algorithm, iterative computation is introduced into the UKF after the measurement update. While the measure- ment noise R is extended into the state vectors before iteration in order to meet the statistic orthogonality of estimate and mea- surement noise. The IUKF algorithm can provide the optimized estimation for the neural network because of its state expansion and iteration. Temperature rise (-20-20℃) and drop (70-20℃) tests for FOG are carried out in an attemperator. The temperature drift model is built with neural network, and it is trained respectively with BP, UKF and IUKF algorithms. The results prove that the proposed model has higher precision compared with the back- propagation (BP) and UKF network models.