被动式半捷联平台的动力学模型及其稳定性分析

在某些高速滚转的制导炮弹中，捷联式惯性测量系统无法同时满足测试精度与量程的要求。被动式半捷联平台可以通过隔离弹体滚转运动有效解决这一问题。通过对弹体及被动式半捷联平台进行力学分析建立了半捷联平台内筒的动力学模型，通过4阶龙格-库塔法对动力学模型进行了数值求解，得出不同弹体俯仰角下平台内筒的滚动角度和角速率值。在三轴高速转台上进行了地面半实物仿真实验，转台实验结果与数值计算结果相符。计算及实验结果表明弹体飞行俯仰角越小，平台内筒的滚动角度和角速率就越小，被动式半捷联平台就越稳定。本研究适用于常规弹药的制导化改造，具有一定的工程应用价值。

Research on the Dynamic Model of a Partial Strapdown Platform and the Impact Analysis of Pitching Angle and the Stability of Platform

To solve the problem of that the traditional inertial navigation system can’t be used in the high speed rolling guided projectile, a partial strapdown platform with special structure is introduced. This platform can keep the micro inertial measurement unit (MIMU) stabilize on the roll axis and remain strapdown on the pitch and yaw axes. The principle of compound pendulum is considered in the design of platform. The stability of the platform is related to the restoring torque of the mass eccentricity. A mechanical dynamics model is established by mechanical analysis of projectile and partial strapdown platform. The roll angle and angular velocity of the platform’s inner shell at different pitching angles are obtained by applying the Runge-Kutta method to solve the differential equations of motion. The experiment is done in three-axis flight simulation test platform. The mechanical dynamics model is verified. The results show that the smaller the missile flight pitching is, the smaller the angle and the angular rate of the partial strapdown platform’s inner shell rolling are, and the more stable the partial strapdown platform is.