应用于红外制导武器的动力随动陀螺误差分析

Errors Analysis of Dynamical Servo Gyro in IR Guided Weapons

为减小红外制导武器导引头的动力随动陀螺误差,对陀螺的误差进行了分析。用拉格朗日方法建立了动力陀螺完备的运动微分方程。将陀螺误差分为结构非理想化导致的漂移误差和稳速力矩与进动力矩耦合引起的控制误差两大类。其中:结构非理想的误差包括章动、摩擦力矩和非等弹性力引起的误差。用逐次逼近求解法分析,发现陀螺受阶跃力矩或冲击后,除按章动频率及高次谐波频率高频振动外,还会发生角速度为常值的漂移,且动力随动陀螺漂移的角速度与初始的角速度和内外环质量有关。讨论了由偏角、不平衡力矩和非等弹性力造成误差的机理。给出了陀螺主要误差的控制和调控方法:对漂移误差,尽量减小内外环质量,减小陀螺阶跃力矩后的初速;对工艺误差,调试时先部件后总体,总体调试由内及外;先大误差项,再小误差项;用力矩补偿法消除力矩耦合偏差。研究为导引头的误差分析和控制系统设计提供参考。

To reduce error of dynamic servo gyro of seeker for infrared guidance weapon, the gyro errors were analyzed in this paper. The complete dynamical model was established by Lagrangian method. The gyro error was divided into two parts which were drift error caused by norrideal structure and control error caused by coupling of speed stabilization moment and procession moment. The structure errors were composed of errors caused by nutation, friction moment and unequal elastic moment. The successive approximation method was applied for analysis. It found that the gyro also made an excursion with a changeless angle rate after the gyro-stabilized seeker came in for an impact except for high frequently libration. The angular speed was depended on the initial angular speed and mass of inner and outer ring. The mechanism of errors caused by drift angle, non-balance moment and unequal elastic moment were given. The control and debugging method of main errors of gyro was given. For drift errors,the mass of inner and outer ring should be as small as possible and initial angle speed should be reduced. For process errors, first was component and then was system for debugging, and the large errors should be debugged ahead the small errors. The moment coupling error was compensated by moment compensation. The study is benefit to guidance for error analysis of seeker and design of control system.