【作者】 练军想；

【导师】 胡德文；

【作者基本信息】 国防科学技术大学 ， 控制科学与工程， 2007， 博士

【摘要】 论文针对捷联惯性导航领域两个方面的关键技术——惯性系动基座对准技术和导航误差转动抑制技术开展研究。主要研究工作包括以下五个方面:(一)系统研究了捷联惯性导航惯性系对准方法。提出了一种利用重力矢量的特征、借助FIR滤波器抑制高频噪声的惯性系对准新方法。根据空间矢量的相互关系,推导了惯性系对准精度与惯性器件误差之间的关系式。设计了两级抽取、分段滤波的FIR低通数字滤波器组,为抑制基座扰动提供了有效手段。研究了惯性系对准方法的快速性和大失准角条件下对准性能。与传统对准方法的比较分析表明:惯性系对准方法具有对准速度快、适用于任意失准角,而且不损失对准精度的优越性能。(二)根据惯性系对准方法的基本原理,结合车载捷联系统对于机动性对准的需求,提出了利用两次短时停车的车载行进间惯性系对准方法,分析了停车位置偏差对精度的影响。结合舰载捷联系统对于航行状态下的对准需求,提出了匀速直航条件下的惯性系迭代对准方法,仿真实验证明了该方法的可行性。(三)采用中等精度(0.01°/h)的激光陀螺捷联系统进行惯性系对准实验,方位精度为0.04°(1σ)。对于地面扰动环境,新方法完成对准需时200秒;对于转台摇摆、船载系泊以及舰载系泊环境,新方法实现对准的时间不超过300秒。与传统反馈控制对准方法相比,新方法在对准速度上明显占优,而且不需要粗对准。实施了行进间对准实验,实现了车载高精度机动对准。设计了以惯性系迭代对准作为粗对准的两步对准方案,实现了舰载近似匀速直航状态下的快速对准。(四)在充分研究了惯性系对准新方法后,论文对惯性导航领域中的另一项关键技术开展了研究:惯性导航误差抑制技术。推导了转动条件下惯性导航误差的解析表达式,对静态和转动两种误差解析式进行对比分析,指出了设计转动角速度时应该规避的谐振频点。分别就往复转动、间断型转动、多轴转动等方式对于导航误差的抑制机理开展研究,推导了往复转动条件下导航误差的解析表达式,利用仿真手段分析了间断型转动对于导航误差的抑制效果。研究表明,合理的转动可以显著抑制器件误差和标定误差的影响。综合比较各种转动方式的优缺点,提出了转动方式的评价准则,为设计实际的转动抑制方案提供了理论指导。(五)设计数学仿真模型,对理论推导的解析结果进行验证,证明了转动条件下导航误差解析表达式的正确性。转台实验和仿真分析均表明:在单轴转动条件下,绕方位轴的往复连续转动具有最优的误差抑制效果。针对某型水面舰船对于惯性导航定位的精度需求,设计采用连续往复转动抑制方案的原理样机,系泊和航行实验的结果表明,采用0.01°/h的激光捷联系统,8小时的定位误差为3海里。更多还原

【Abstract】 The thesis has investigated two key technologies involved in strapdown inertial navigation system (SINS). One is the moving-based alignment through an inertial frame; the other is the depressing of navigation errors by rotation. The content mainly comprises of the following five aspects.1. A systematic study is performed on the inertial frame based alignment (IFBA) method, which uses the gravity vector and its derivative. By virtue of a cascade of low-pass FIR filters, IFBA attenuates the disturbing acceleration and maintains the gravity. According to the geometric relations among space vectors, the analytical expression relating the navigational errors to the instrumental errors is derived. In order to attenuate the disturbing of vehicles, an FIR filter group consisting of two decimations and three sub-filters is designed. Rapidness of the IFBA method is discussed, and the ability to conquer large misalignment is confirmed. Comparisons with other traditional algorithms prove that proposed method converges much faster than the conventional methods at no cost of precision and also works well under any large initial misalignment.2. According to the basic principle of the IFBA method, a maneuverable alignment algorithm for vehicle-based SINS with twice short stops is proposed. The relationship between the alignment error and the relative position error is illustrated. To satisfy the requirement of alignment during sailing, an iterative alignment method for ship-based SINS is designed and simulation verifies its feasibility.3. The performances of the IFBA method is tested by a navigation grade SINS (0.01/h, ring laser gyroscopes) and the azimuth aligning accuracy is 0.04 (1σ). For disturbing ground condition, experiments show that the IFBA method needs 200 seconds. And for swaying marine condition, the aligning time is not more than 300 seconds. Compared with the traditional algorithms, IFBA method has obvious advantage in alignment time and does not need coarse alignment stage. Vehicle experiments show that the maneuverability of the vehicle is improved by using the proposed algorithm. To deal with the aligning problem during sailing, an alignment scheme comprising a coarse step by the IFBA method and a fine step by a Kalman filter is presented. The ship-based alignment experiment proves that the proposed scheme works well for the condition with approximate constant speed. 4. After the IFBA method, the thesis investigates another key technology: the depressing of inertial navigation errors. The analytical expressions of navigation errors when rotating are derived and compared with the static results. The resonant frequency of the rotation scheme is indicated. In addition to single direction rotating, the principles of reciprocative rotating, intermittent rotating and multi-axis rotating are also investigated. The analytical error expressions of reciprocative rotating are derived. And the performance of intermittent rotating is examined through simulations. It shows that well-designed rotation can depress the influences of instrumental errors and of calibration errors remarkably. Advantages and disadvantages of the rotating schemes are analyzed, and the rules of the evaluation are presented for actual system design.5. A simulation model based on Matlab/Simulink is designed to prove the analytical results. Table experiments and simulations show that the performance of reciprocative rotation about the azimuth axis is optimal. A prototype with reciprocative rotation scheme is designed for a real naval ship. Using a SINS made up of 0.01°/h ring laser gyroscopes, mooring and sailing experiments show that the position error is no more than 3 nautical miles in 8 hours.更多还原