基于H∞滤波技术的重力辅助导航仿真研究

Simulation research on gravity aided navigation based on H_∞ filter theory

因无法对系统模型和噪声模型精确建模导致Kalman滤波器精度较低或发散问题,本文将H∞滤波理论引入重力仪/INS组合导航系统。文中首先给出了最优H∞范数的计算方法,解决了过去根据经验或多次试验确定该值的问题。组合导航系统包含位置、速度和姿态9维状态误差,利用重力仪实测重力异常与INS指示位置地图重力异常值之差作为观测信息对系统进行H∞滤波。仿真实验表明,该方法可极大地改善组合导航系统的鲁棒性和可靠性,明显提高系统的导航精度,减小滤波系统的阶次,加快对系统状态的滤波估计,对工程实际应用具有重要意义。

The precision of the traditional Kalman filter is lower or emanative because the accurate error model is inexistent, in this paper H∞ filter theory is introduced into the integrated gravimeter/INS system. The ealculational methods of the optimization H∞ -norm is given firstly in order to solve the problem which the value is determined by the past experience or the experiment. Its state variables include the errors of the three direction position, velocity and attitude, the measurement values is composed of the difference which is the measurement gravity abnormity in real time subtracts that of the gravity map value of the INS position. The dynamic simulation is carried out and the result shows that the technology in this paper is feasible and it can improve the system robustness, reliability and navigation precision, reduce the system complexity. The scheme can be put into practice easily.