舱内动环境对捷联惯导外杆臂误差补偿影响机理分析

分析飞行器舱内复杂动环境对捷联惯导的影响是提高惯性导航精度的技术难题之一。在仅考虑横向振动和线性系统的假设前提下,将舱内捷联惯导等效为简支欧拉梁和阻尼弹簧振子混合系统,给出了舱内动环境条件下的动力学微分方程并求解其响应,得出作为确定性矢量处理的外杆臂随混合系统响应出现随机变化是造成捷联惯导加速度计外杆臂误差补偿不完全的重要原因,结合外杆臂误差的计算方法,推导了其随机变量的数字特征和动环境下误差表达式。在此基础上,通过仿真飞行计算,分析了外杆臂误差补偿不完全对导航迭代解算的影响。

Mechanism analysis of dynamic environment in apparatus cabin for strapdowninertial navigation system external lever arm effect compensation

The influence of complex dynamic environment in apparatus cabin for strapdown inertial navigation system (SINS) is one of the technical problems to improve navigation accuracy. The strapdown inertial system is equivalent to Euler-beam hybrid system, which is considered under the hypothesis premise of only transverse vibration and linear system. The system motion is described by dynamic differential equations, and find out the root cause of external lever arm effect incomplete compensation is the external lever arm changed with the random response under dynamic environment. The digital characteristics of the random variable and the dynamic external lever arm effect expression is derived according to the traditional lever arm effect computing method. Finally, the influence of lever arm effect incomplete compensation on navigation solution is analyzed with the flight simulation.