船用平台式INS光学标校初始对准方法研究

为了解决航海型平台式惯性导航系统（INS）非自主式初始对准问题，建立了不同观测量条件下统一的INS初始对准方程。通过系统可观测性分析，得出增加外部姿态角的观测信息将有效提高INS平台失准角和惯性元件误差的估计能力的结论。设计出一种独特的可测量低动态载体两维姿态的高精度光学测量系统（OCS）用以提高航海型平台式INS初始对准精度。建立OCS／GPS／计程仪（LOG）／INS初始对准卡尔曼滤波器，并进行了基于部分试验数据的数字仿真，与传统的基于位置和速度的GPS／LOG／INS初始对准方法相比，基于OCS的系统不仅缩短了对准时间，还有效改善了系统惯性元件的误差估计精度。

Research on Initial Alignment of Marine GINS Based on Optical Calibration System

A novel approach was proposed to solve the non-autonomous initial alignment problem of marine gimbal inertial navigation system (INS). Through the analysis of the system observability based on general error model of GINS initial alignment for different kind of measurement, more external altitude measurements can improve the estimation of INS platform misalignments and instrument biases. In order to enhance INS initial alignment performance, an accurate optical calibration system (OCS) adopting two total stations was designed to obtain high accurate external altitude reference for lower dynamic ship. The Kalman filter using external position, velocity and altitude based on OCS, GPS and log integrated with INS was employed to achieve initial alignment of INS. Comparing to the method using external position and velocity, the Monte-Carlo numerical simulations based on experimental data verify that proposed method is capable of providing high performance both in higher accuracy and less alignment time.