大摇摆情形的自对准方法  

A self-alignment method on large swing situations

作　　者：牟玉涛[1] 方海涛[1] 

机构地区：[1]中国科学院数学与系统科学研究院,国家数学与交叉科学中心,北京100190

出　　处：《中国科学：信息科学》2012年第11期1364-1378,共15页Scientia Sinica(Informationis)

基　　金：国家自然科学基金(批准号:61174143)资助项目

摘　　要：在风等干扰的影响下,载体易产生较大幅度的摇晃,造成捷联惯导系统初始姿态存在较大失准角,而由于缺少基准信息,并且包含失准角信息的导航误差不能直接量测,进而影响自对准精度.由于载体仅发生摇晃,并没有相对移动,从而存在零速的摇晃中心,若视载体为刚体,则载体各点的姿态是相同的.由于摇晃中心处的自对准是较为成熟的静基座对准问题,从而只需获得摇晃中心处的姿态误差即可.为了获得摇晃中心的位置,我们利用杆臂效应原理,通过将水平失准角扩展为待估参数,减小了模型误差,提高了摇晃中心位置的估计精度.对于摇晃基座存在大失准角问题,利用估计状态闭环补偿系统模型,逐步减小模型误差,获得较好的对准精度.最后通过仿真例子进行了验证.On the influence of some disturbances such as wind,the large amplitude motion will be caused.In these situations,for the strapdown inertial navigation system,there are the large misalignments in the initial phase,and the errors caused by misalignments can not be directly observed.However,for self-alignment,the information of these errors is very important.Since the system does not move in the swing situation,there exists a shake center whose speed is zero.If the system is a rigid body,then the attitude errors in the shake center are same as that in all of the system,and the self-alignment problem in shake center is same as that in the stationary case.Therefore,we only need to obtain the attitude errors in the shake center.Based on the principle of the lever arm effect,we provide a method to obtain the position of the shake center from the measurements of inertial measurement unit.To estimate the position of shake center,the level attitude errors are estimated at same time to reduce the model uncertainty.We also show that the alignment accuracy can be improved step by step by using the estimated parameters to compensate the system model uncertainty in the large misalignment case.Finally,some simulation results are presented to verify the method given in this paper.

关 键 词：自对准 大失准角 摇摆基座 杆臂效应 最小二乘方法 

分 类 号：TN966[电子电信—信号与信息处理]