滚仰式光电吊舱地理导引实现与误差分析

Realization and error analysis of geographical guidance for roll-pitch electro-optical pod

为了提升地理导引精度和成功率,根据滚仰式光电吊舱的结构特点,通过建立坐标系统、目标坐标求解和框架角解算三个步骤,完整构建了地理导引的数学模型,并在此基础上引入了速度前馈和小区域搜索模式。同时,对受惯导测量误差和目标距离影响的框架角解算误差进行了数据仿真。结果表明:经纬误差和航向角误差对俯仰角的解算误差影响较大;而高程误差和水平姿态角误差则对横滚角的解算误差影响较大。提升惯导的定位精度,可进一步减小框架角解算误差,从而提升地理导引精度,而当航向角<0.1°,水平姿态角<0.05°时,姿态角误差的影响权重会变小,再通过减小姿态角误差提升导引精度的作用已不明显。随着目标距离的增大,框架角解算误差会急剧减小。最后进行了导引试验,其俯仰、横滚角均方差均小于0.12°,表明了算法的准确性和仿真分析的有效性。

In order to improve the accuracy and success rate of geographical guidance,according to the structural characteristics of the roll-pitch electro-optical pod,a mathematical model of geographical guidance was developed through three steps:first,establishing the coordinate system;second,solving the target coordinates;and third,calculating the frame angle.Speed forward feed and small domain search modes were introduced on this basis.The frame angle calculation error affected by inertial navigation measurement error and target distance was simulated,and the results show that the longitude,latitude,and heading angle errors had a greater influence on the pitch angle calculation error;nonetheless,the errors of elevation and horizontal attitude angle had a greater influence on the calculation error of the roll angle.Improving the positioning accuracy of inertial navigation can further reduce the frame angle calculation error and improve the geographical guidance accuracy.However,when the heading angle decreases below 0.1 degrees and the horizontal attitude angle decreases below 0.05 degrees,then the influence weight of the attitude angle error also decreases.The improvement in guidance accuracy is no longer evident when attitude angle errors are reduced.Increasing target distance sharply decreases the error of frame angle calculation.Finally,the guidance test with pitch and roll mean square errors of less than 0.12 degrees shows the algorithm's accuracy and the simulation analysis's effectiveness.