重力扰动对惯性导航系统初始对准的影响

随着惯性器件精度的不断提高与高精度导航系统发展的需要,重力扰动成为影响惯性导航系统(inertial navigation system, INS)精度的主要误差源之一。在考虑垂线偏差和重力异常的同时,首先利用解析法推导了重力扰动影响初始对准失准角的误差方程,并将其转化为姿态角误差方程。然后,分析并建立了INS的速度、位置和姿态的误差方程。最后,利用仿真实验验证了重力扰动对INS初始对准的影响。理论分析及仿真实验表明,重力扰动矢量直接影响初始对准姿态角,姿态角误差仅与水平面内的垂线偏差有关,而与重力异常无关。

Influence of gravity disturbance on initial alignment of inertial navigation system

With the continuous improvement of the accuracy of inertial devices and the development of high-precision navigation systems, disturbing gravity has become one of the main sources of error affecting the accuracy of inertial navigation system (INS). While considering the vertical deviation and gravity anomaly, firstly, the error equation of the gravity disturbance affecting the initial alignment misalignment angle is derived by analytical method, and converting it into attitude angle error equation. Then, the error equations of the speed, position and attitude of the INS are analyzed and established. Finally, the effects of gravity disturbance on the initial alignment of INS are verified by simulation experiments. Theoretical analysis and simulation experiments show that the gravity disturbance vector directly affects the initial alignment attitude angle. The attitude angle error is only related to the vertical deviation in the horizontal plane, not related to the gravity anomaly.