纵向振动对捷联惯导误差影响半解析表达式研究

Semi-Analytic Function of SINS Error Under Longitudinal Vibration Condition

针对实际动态工况条件下捷联惯导输出与静态条件下输出存在一定误差的问题,在仅考虑纵向振动的条件下,将飞行器仪器舱内的惯导系统等效为杆与阻尼弹簧振子的组合系统,利用复模态分析方法使方程解耦,并推导了动态扰动环境中惯导加速度响应的半解析表达式,给出了实际敏感加速度的包络范围,指出捷联惯导加速度计敏感值变为围绕真实值分布的随机变量是动态环境条件下产生加速度误差的根本原因之一。

Focusing on the SINS error between dynamic and static environment,the strap-down inertial system was equivalent to rod with damping spring vibrator system, which is considered under the hypothesis premise of exist only longitudinal vibration,and differential equation was decoupled with complex modal analysis,and the SINS error semi-analytic function under dynamic environment and the acceleration envelope range was deduced,and it finds out that the root cause of SINS error is the acceleration changed to a random variable around the true value under dynamic environment.