【作者】 张燕；

【导师】 郝应光；

【作者基本信息】 大连理工大学 ， 通信与信息系统， 2008， 硕士

【摘要】 捷联式导航系统是惯性导航系统中的一种,它与平台式导航系统相比具有体积小、重量轻、成本低的特点,是今后惯性导航系统的发展方向。本文首先介绍了捷联惯性导航系统(SINS)的导航原理,探讨了捷联惯性导航系统初始对准和导航解算的算法、飞行轨迹数据生成算法,然后利用MATLAB/Simulink仿真软件,对捷联惯导系统的导航工作过程进行了仿真计算。由于惯导系统导航参数的误差随着时间而积累,纯捷联惯导系统无法满足长时间、远距离的导航要求。实际中常采用GPS/SINS组合导航技术来提高系统的精度及可靠性,本文采用卡尔曼滤波方法对其进行了仿真研究。实验结果显示仿真系统工作稳定可靠,仿真结果达到预期效果。初始对准是捷联惯导系统的关键技术之一,它直接影响捷联惯导系统的导航性能。考虑到低精度的捷联惯导系统,其陀螺精度较低,初始对准时方位失准角的估计精度往往不高;另外,进行初始对准的常用方法是采用卡尔曼滤波技术,但在实际应用时,其鲁棒性不高,因此迫切需要一种能够改善低精度捷联惯导系统方位失准角的估计精度且兼具鲁棒性的初始对准方法。本文提出了一种将H∞滤波用于引入磁航向的低精度捷联惯导系统的初始对准方法,能够解决这一问题。文中建立了一种引入磁航向的捷联惯导系统初始对准的误差模型,通过可观测性和可控性分析,得出其为可观可控系统,在此基础上利用H∞滤波方法对其进行了仿真分析,仿真结果表明,该方法能够改善低精度捷联惯导系统方位失准角的估计精度,并能有效抑制有色噪声及建模误差的影响,将其应用于低精度捷联惯导系统的初始对准是切实可行的。更多还原

【Abstract】 Strapdown inertial navigation system (SINS) is a type of inertial navigation systems. Compared with platform inertial navigation system, strapdown inertial navigation system has the advantages of low volume, low weight and low cost. Strapdown inertial navigation system leads the trend of inertial navigation systems.In this paper, the principles of SINS navigation are introduced, and the method of initial alignment of strapdown inertial navigation system, the method of calculation of navigation, method of generating flight orbit data are discussed in detail. Then the paper develops the whole system with MATLAB/Simulink. Because the system error of SINS accumulates with time, pure SINS can hardly meet the requirements of longtime, distant navigation. To solve this problem, GPS/SINS integrated navigation system is commonly used to improve the accuracy and reliability. Simulation of GPS/SINS integrated navigation system based on Kalman filter algorithm is studied in this paper. The result shows that the simulating system is steady and reliable and the simulating result is satisfying.The initial alignment is one of the most important key techniques of the SINS, which impacts directly on the precision of the SINS. Because of the low precision of gyros in low-accuracy SINS, the accuracy of estimate of azimuth angle misalignment is not very high; and the Kalman filter is commonly used in initial alignment, which shows low robustness in practical application, thus an approach which can improve the accuracy and robustness for initial alignment of low-accuracy SINS is urgently needed. Through the introduction of magnetic heading, a new method of initial alignment has been developed for low-accuracy SINS by using H_∞filter, which can solve the problem. An error model of SINS with magnetic heading is proposed. The observability and controllability of the model is analyzed, and concluded that the system is observable and controllable. The H_∞filter is designed, and the simulation results illustrate that this method can restrain colored noises and modeling error effectively. This approach can be used in initial alignment of low-accuracy SINS.更多还原