基于落点预测的高旋火箭弹弹道修正算法

Ballistic trajectory correction algorithms of high-spin rocket based on impact point prediction

高旋火箭弹的修正控制是基于等效力实现的二维弹道修正控制,由于弹体存在陀螺进动和马格努斯效应,在控制力作用下产生的附加攻角引起的升力与控制力的矢量合为等效力,其大小与方向在控制过程中不断变化,不能简单根据偏差量(修正量)的比例关系来确定控制力的方向。基于此,分析了控制力与等效力的关系,提出了一种基于弹道落点预测的控制算法。首先利用弹道落点预测模型实时预测落点与目标的偏差量,然后利用小扰动法构造偏差量对控制量的敏感系数矩阵,通过偏差量与敏感系数矩阵解算出纵、横两个方向的需用控制量。采用修正前后速度矢量的位置关系得到控制量的合矢量及其方位角,并利用控制量的合矢量与等效力计算出控制周期,在控制周期内按照等效力方位角调整控制力的方向实现对高旋火箭弹的精确控制,解决了非线性耦合问题。仿真结果表明该算法具有较高的控制精度,为工程应用提供理论依据。

The trajectory corrective control of high-spin rocket is a two-dimensional correction control based on equivalent force.Due to gyro precession and the Magnus effect of high-spin rocket,the equivalent force is formed by the control force,and the force caused by the additional angle of attack under the action of the control force,the magnitude and direction of the equivalent force is constantly changing during the control.Therefore,the direction of control force can’t be determined simply by the proportional relation of deviation(correction quantity).Based on this,the relationship between control force and equivalent force is analyzed in this paper.A corrective algorithm based on trajectory impact point prediction is proposed.At first,the deviation between the rocket’s landing point and its target position is predicted in real-time using the impact point prediction model.Then the paper established corrective sensitivity coefficient matrix based on the small perturbation method,and the control quantity in both longitudinal and transverse directions were obtained through the deviation and sensitivity coefficient matrix.The combined vector and azimuth of the control quantity were obtained by using the relationship of velocity vector before and after the correction control,and the control period was calculated by using the control quantity and the equivalent force.In the control period,the direction of the control force was adjusted according to the azimuth of the equivalent force angle,the accurate control of the high-spin rocket was obtained,and the problem of non-linear coupling was solved.The simulation results show that the algorithm has high control accuracy,providing theoretical basis for engineering application.