针对GPS/INS组合导航中INS动力学建模不准确的问题,提出了一种基于牛顿插值的GPS/INS组合导航惯性动力学多阶建模算法。首先,介绍了牛顿插值的计算方法;然后,利用其对惯性系统Gauss—Mark—OV模型进行改进,实现了多阶建模;最后,给出了组合导航详细的动力学模型和观测模型。利用实测数据对算法进行验证,并通过对比不同阶数建模方法寻求牛顿插值的最优建模阶数。结果表明,相比于传统Gauss—Markov过程,基于牛顿插值的GPS/INS组合导航惯性动力学模型能够有效提高组合导航位置精度和姿态精度。与此同时,实验分析表明,4阶牛顿插值建模在实现模型准确性的前提下,降低了模型的复杂性,为牛顿插值建模阶数选取提供了良好的借鉴。
In GPS/INS integrated navigation, the low precision of the INS dynamic model reduces nav-igation accuracy. Based on Newton interpolation, a multi-order dynamic model algorithm for GPS/INS integrated navigation is proposed. First, the detail algorithm of Newton interpolation is introduced. Based on this a Gauss-Markov model of the inertial system is modified to realize the multi-order mod- el. The design formulas of the observation and dynamical models are presented. Finally, an actual cal- culation was performed to test the validity of new algorithm. The results of the experiment indicate that when compared with the Gauss-Markov model, the inertial dynamic model for GPS/INS integrat- ed navigation based on Newton interpolation can improve the position and attitude precision effective- ly. At the same time, an analysis of the experiment shows that a 4-order Newton interpolation model not only enhances model precision, but also reduces model complexity, which provides a good refer-ence for order selection in the Newton interpolation model.