微小型导航制导控制系统MGNC(Micro Guidance Navigationand Control)传感器多,且数据处理能力有限,为实时提供导航结果,传统上采用降维滤波提高实时性,但这样会造成精度损失.为保证不减少滤波状态量,不损失精度,针对捷联和滤波特点提出一种新的实时解算方法:在捷联解算中以直接递推求解方向余弦矩阵代替以四元数为中间变量进行的间接求解;在滤波计算中用序贯方法处理量测修正值,避免复杂的矩阵求逆;采用稀疏矩阵三元组法,应用于协方差阵计算,减少乘法次数.仿真和实验证明改进算法对计算精度没有损失,且滤波计算时间比原算法减少了34.50%,显著提高了MGNC系统的实时性、鲁棒性和实用性.
To reduce the computation time of the integrated navigation, an improved algorithm was pro- posed without model state vector reduction for the micro guidance navigation and control (MGNC) system. The direction cosine matrix was deserved by iterative computation instead of using quaternion as an intermedi- ary. The measurement correction was processed one by one to avoid computing the matrix reciprocal. A triple elements method was proposed based on the sparseness of the transformation matrix while calculating the covar- iance matrix forecast equation. Mathematical simulation and experiment show that the improved algorithm can provide the same accuracy as the traditional method for navigation and can reduce the filtering calculation time by 34.50%. The method can improve the robustness of the MGNC system and is quite useful in practical application.