简化UKF滤波在SINS大失准角初始对准中的应用  

Application of simplified UKF in SINS initial alignment for large misalignment angles

作　　者：严恭敏[1] 严卫生[1] 徐德民[1] 

机构地区：[1]西北工业大学航海学院,西安710072

出　　处：《中国惯性技术学报》2008年第3期253-264,共12页Journal of Chinese Inertial Technology

基　　金：中国博士后科学基金(20070420215);水下信息处理与控制国家级重点实验室基金(9140C230206070C2306)

摘　　要：基于欧拉平台误差角的概念提出了大失准角误差条件下的捷联惯导系统(SINS)非线性初始对准误差模型,该模型无法再用经典的加性噪声模型描述。为了降低滤波计算量,在系统模型噪声和量测噪声均为复杂加性噪声并且量测方程是线性方程时,推导了简化的UKF(unscented Kalman filter)滤波方法,简化UKF滤波公式显示:除通过非线性状态方程使用UT(unscented transformation)变换进行状态及其方差预测外,其它滤波步骤与标准Kalman滤波完全相同。最后,对静基座下SINS初始对准进行了仿真试验,结果表明大失准角条件下的SINS误差模型和简化UKF滤波估计方法是有效的。SINS nonlinear error model was deduced based on the concept of Euler platform error angles（EPEA） with large initial misalignment angles, and this nonlinear error model could no longer be presented by using the classical additive noise models. To reduce the calculation burden, a simplified UKF（unscented Kalman filter） filtering algorithm was derived under the situation that both process noise and measurement noise were complex additive noise with linear measurement equation. The simplified UKF algorithm is identical to that of classical Kalman filter except for the predicting of states and their covariance matrix by unscented transformation （UT） in nonlinear state model. In the end, SINS initial alignment simulation tests under large EPEA were executed, and the results verified the proposed SINS error model and the simplified UKF algorithm.

关 键 词：UKF滤波 捷联惯导系统 初始对准 大失准角 仿真 

分 类 号：U666.1[交通运输工程—船舶及航道工程]