局部可观测理论在INSGPS机动对准中的应用

Application of Local Observability Theory in the In-Flight Alignment of INS/GPS

从研究INS GPS(InertialNavigationSystem GlobalPositioningSystem)组合系统的姿态角误差可观测性出发 ,首次将局部可观测性理论应用于INS GPS组合系统 ,定量地计算出各种不同机动方式的局部可观测矩阵的条件数 ,找到了提高姿态角误差可观测性的最佳机动方式 .研究结果表明 ,通过载体做正弦水平机动飞行可以提高姿态角误差局部可观测性 ,使空中对准时间明显减少 ,姿态角误差大大降低 .当对准时间为 1 2 0s时 ,东北天向姿态角误差的均值分别为 1 2 .3 4″,1 2 .1 9″和- 2 8.3 1″,它们的均方根值分别为 0 .97″,1 .0 5″和 0 .6 2″ .

Based on the study on the observability, the local observability theory has been used in INS/GPS integrated system, the condition number of local observability matrix in various maneuver modes have been computed, and the optimal maneuver mode has been found. It has been shown by the research results that, by means of implementing sine level maneuver flight, the local observability of the attitude errors can be increased, the flight alignment time can be reduced obviously, and the attitude errors can be cut down greatly. When the alignment time is about 120?s,the mean values of attitude errors in the directions of east, north and up are 12.34″ , 12.19″ , -28.31″ , and their standard deviations are 0.97″, 1.05″, 0.62.