船用捷联惯性导航系统在系泊状态下快速初始对准与标定

Initial rapid alignment/calibration of a marine strapdown inertial navigation system in moorage

针对船用捷联惯性导航系统(S-INS)在系泊状态下的初始对准与标定,提出一种两位置对准方法.该方法首先建立在水平失准角较小、而方位失准角较大时的初始对准模型,并在传统的卡尔曼滤波器中加入前置滤波器,对受干扰的2个水平速度信号采用非平稳求和自回归滑动平均模型(ARIMA)建模,然后在建立测量信号精确模型的基础上,再进行卡尔曼滤波,这样降低了观测噪声的水平,达到快速精确对准及IMU误差参数在线标定的目的.通过在三轴转台上多次试验结果表明,使用中等精度的惯性组件,在1 200 s内,水平姿态估计误差将减少到0.03°,方位误差减少到0.4°以内,证明了该方法的有效性.

A two-position alignment method for initial alignment of strapdown inertial navigation systems has been developed for ships in moorage. Firstly, an initial alignment model was established for the situation where the level misalignment is small and the heading misalignment is large. Pre-fihering was embedded in the conventional Kalman filter to reduce the level of noise in the measurement signal. In addition, for two signals of interfered horizontal velocities, non-stationary autoregressive integrated moving average （ARIMA） modeling was adopted. Then, a Kalman filter was executed after the model of the measured signal was established. In this way, the noise level was reduced and the rapid alignment and calibration of inertial measurement unit （IMU） parameters were achieved. Experimental results in a three-axis turntable indicated that, the level and azimuth errors were controlled within 0.03° and 0.4° in 1 200 seconds with medium-accuracy IMUs used, proving the validity of this approach.