【作者】 王涛；

【导师】 徐德民；

【作者基本信息】 西北工业大学 ， 武器系统与运用工程， 2006， 硕士

【摘要】 惯性导航误差随时间累计而增大，又由于水下环境的非结构性、复杂性和不稳定性等特点，使得水下导航比较困难。为了适应现代水下航行器导航系统在精度、可靠性和智能化方面越来越高的要求，本文主要研究了地形辅助导航中最经典算法之一桑迪亚惯性地形辅助导航(SITAN)系统及其改进算法，将这些方法分别应用到水下航行器上，仿真结果表明改进后的算法不仅精度高而且可以有效的抑制发散，从而提高了系统导航精度和可靠性。 针对上述研究的目的，本文主要研究成果与创新点有以下几个方面： (1) 简要地介绍了国内外地形辅助导航的发展概况，阐述了地形辅助导航当前研究的重点方法之一桑迪亚惯性地形辅助导航(SITAN)系统。 (2) 通过MATLAB软件中peaks函数和二维随机过程构建了仿真用的人工模拟地形，并对其性能指标、地形随机线性化技术和地形存储技术进行了分析和研究。 (3) 深入地研究了捷联惯导系统的工作原理、基本算法和误差传播特性，并以中等精度的惯性器件构成捷联惯导系统作为仿真对象，进行了数字仿真，仿真结果表明惯性导航系统误差随时间累计而增大，此系统的导航精度远不能满足水下航行器的定位要求。 (4) 提出了以扩展卡尔曼滤波(EKF)为基础的桑迪亚惯性地形辅助导航(SITAN)算法，将此算法应用到水下航行器中进行数字仿真，结果表明此算法精度比较高，但由于系统的数学模型简化、噪声的测量模型的不准确及在滤波递推过程中引起的误差累积导致系统发散。 (5) 分析了自适应滤波的原理，提出了三种基于自适应滤波(AEKF)的桑迪亚惯性地形辅助导航算法，将这些方法分别应用到水下航行器中，仿真结果表明所提出的这些算法估计精度和收敛速度均好于以扩展卡尔曼滤波为基础的桑迪亚惯性地形辅助导航(SITAN)算法，可以有效的抑制发散，以提高导航的精度和可靠性。更多还原

【Abstract】 Because of the cumulative error of the inertial navigation, and because of the unstructured, complexity and instability of underwater surroundings, inertial navigation system can’t provide perfect position and navigation in a long time. In order to adapt more and more requests of modernized submarine navigation system in the precision, reliable and the intellectualized aspects, this paper researches Sandia terrain-aided navigation system (SITAN) system and its improvement algorithm. These methods apply and simulate separately in the underwater navigation, the result indicated the precision and convergence of the improvement methods is higher than the old.Based on the above, the main contribution of this dissertation is summarized as following:(1) This paper introduces briefly about domestic and foreign situation of development terrain-aided navigation. It elaborates SITAN system which is one of most classical algorithms of terrain-aided navigation.(2) The simulant topography is established by peaks function in MATLAB and two-dimentional stochastic process, and its performance index, the terrain stochastic linearization and the terrain storage technology are elaborated in detail.(3) On the basis of research of SINS working principal and basic algorithm and error spread character. Furthermore with the medium precision Inertial Navigation device as the simulation object. The result indicated the navigation precision of this system can’t meet the localization requirement for the AUV because of the cumulative error of INS.(4) Extended kalman filter based on SITAN is proposed. This method is applied to AUV and simulated. The result indicates the precision of algorithm is high. Because of the simplified mathematical model of the system, the inaccurate measurement model of noise and the cumulative error of recursive filter, the system is divergent.(5) This paper analyzes the basic principle of AEKF. several kinds of the improvement adaptive extended kalman filter based on SITAN is proposed in this article. These methods are applied in the submarine navigation and simulated, the simulation result indicated these algorithms has better performance in the estimate precision and astringency, and enhance the更多还原