基于改进混杂扩展卡尔曼滤波的炮弹阻力系数辨识

针对利用炮弹飞行数据辨识阻力系数的问题,提出了一种改进形式的混杂扩展卡尔曼滤波(IHEKF)方法。引入虚拟过程噪声并且在每个时间步长对称化协方差矩阵,避免了混杂扩展卡尔曼滤波在实际应用中由于系统建模误差及弹载计算机的精度有限引起的发散问题,提高了阻力系数辨识的鲁棒性。数值仿真结果表明:当建模误差可以忽略不计时,采用IHEKF能以高精度辨识出阻力系数; 当建模误差较大时,采用IHEKF具有较好的鲁棒性。

Drag Coefficient Estimation for Projectiles Based on ImprovedHybrid Extended Kalman Filter

An improved hybrid extended Kalman filter(IHEKF)was proposed aiming at drag coefficient estimation from flight data of projectiles.The fictitious process noise was added to the system model,and the covariance matrix was symmetrized at each time-step.The divergence caused by modeling errors and finite precision of digital microprocessors onboard the projectiles in the implementation of HEKF is avoided,and the robustness is improved.While the modeling errors can be ignored,the IHEKF can estimate the drag-coefficient with high-precision;while the modeling errors are great,IHEKF has great robustness.