基于SINS/OD失准角观测的垂线偏差测量方法

Deviation of vertical measurement method based on SINS/OD misalignment angle observation

组合导航系统的姿态失准角与垂线偏差(deviation of vertical,DOV)存在对应关系,通过对姿态失准角的观测是实现DOV测量的一种有效手段。本文基于车载捷联惯性导航系统/里程计(strapdown inertial navigation system/odometer,SINS/OD)组合导航姿态失准角观测及失准角误差的递推提出一种DOV测量方法。首先,从组合导航速度误差方程出发,推导出DOV与姿态失准角之间存在复杂的耦合关系。然后,通过沿路径迭代递推的分步计算方法,由导航过程中的姿态失准角直接获取沿线的DOV。最后,仿真结果验证了该算法的有效性,且表明测量精度与行驶路径的长度有关。实验表明,行驶里程35 km的机动路径上DOV误差均值小于0.3″,终点处单点测量误差小于0.7″。

There is a correspondence between attitude misalignment angle of integrated navigation system and deviation of vertical(DOV).It is an effective method to measure DOV by observing attitude misalignment angle.This paper presents a measurement means of DOV based on strapdown inertial navigation system/odometer(SINS/OD)integrated navigation attitude misalignment angle observation and error recursion.Firstly,starting from the velocity error equation of integrated navigation,the complex coupling relationship between the DOV and attitude misalignment angle is deduced.Then,the DOV is directly obtained from the attitude misalignment angle in the navigation process through the step-by-step calculation method of iteration and recursion along the path.Finally,simulation results verify the effectiveness of algorithm and show that the measurement accuracy is related to the length of the driving path.The experimental results show that the average error of DOV is within 0.3″on the driving path with a driving distance of 35 km,and the single point measurement accuracy at the end point can reach 0.7″.