基于地籍测量的惯性系统初始对准方法研究

Study on Initial Alignment of Inertial System Based on Cadastral Surveying

地籍测量过程中具有静态、可调平和转位的特点,在静基座条件下,捷联惯性测量系统(SIMS)粗对准的失准角与卡尔曼滤波精对准的失准角相当,但是解析粗对准的方位角误差较大。本文在建立SIMS静基座粗对准误差方程的基础上,对影响解析粗对准精度的误差因素进行分析,提出利用光纤陀螺寻北仪进行四位置转位寻北的方法来估算方位角的精度,以提高方位角的估计精度。仿真结果表明,该方法可以有效地提高对准精度,适合于静基座外界干扰小的捷联式惯性测量系统上,在一定程度上可以直接作为对准的结果用于地籍测量定位解算。

Cadastral surveying process has features of static, adjustable and translocation. In the stationary base conditions, the misalignment angles of coarse alignment of Inertial Measurement System （SIMS） parallel fairly with the misalignment angles of fine alignment of Kalman Filter, but the azimuth error of coarse alignment is larger. On the basis of establishing the error equations of analytic coarse alignment for SIMS on stationary base, this paper analyzes the factors that affect the precision of coarse alignment error, puts forward to using the method of four position found north to estimate the accuracy of the azimuth, to improve the estimation accuracy of azimuth. The simulation results show that compared with the coarse alignment result, this method can effectively improve the alignment accuracy, suitable for the stationary base and small interference of SIMS, which, to a certain degree, can be directly used as a result of the alignment of cadastral surveying positioning algorithm.