【作者】 陈明辉；

【导师】 郝燕玲；

【作者基本信息】 哈尔滨工程大学 ， 控制理论与控制工程， 2008， 硕士

【摘要】 作为舰船、飞机、航天器等载体上的重要设备,捷联式惯性导航系统(SINS)无论在军用还是民用领域,都发挥着重要作用。然而,捷联惯导系统在具有自主式导航、短期精度高、稳定性好等优点的同时,也具有自身无法避免的缺陷。传统的自主式初始对准方式对准时间长,而且要求在静基座上进行,不符合实际系统的应用需要;此外,纯惯性导航系统由于器件原因误差随时间积累,很难达到相当高的精度。因此,研究捷联惯导系统的误差特性和基于此的组合对准方法具有重要的现实意义。本文首先根据捷联惯导系统的工作原理,推导并建立了系统在静基座和动基座条件下的误差方程,分析了载体在静止和运动状态下的误差特性。在三种主要误差源的激励下,系统产生常值误差和呈三种周期振荡的误差,并且载体的机动将使系统的振荡周期发生改变。在SINS误差分析的基础上,为了分析载体的运动和不同的组合对准方式对系统性能和对准效果的影响,本文建立了多种方式组合对准的数学模型(包括速度组合、位置组合、位置与速度组合、速度与姿态组合),并分别对它们进行了可观测性分析和系统仿真。由于误差特性中状态量之间耦合程度的差异,速度与姿态组合的对准效果最好,精度最高,位置与速度组合、速度组合次之,位置组合最差,并且载体的机动可以明显提高系统的可观测性,甚至可以突破器件误差(主要是陀螺漂移)对失准角的影响,使对准精度达到一个更高的数量级。针对静基座下惯性器件误差不能有效估计和方位对准精度不高的缺点,本文提出了一种新的两位置组合对准方法,通过仿真分析表明,这种方法能准确的估计出陀螺漂移(主要是水平陀螺漂移),显著提高初始对准的精度。最后,本文通过转台实验验证了在静止和摇摆状态下利用卡尔曼滤波法进行组合对准的可行性,证明了卡尔曼滤波相对于传统经典控制理论来说显示出特有的优越性,具有实用价值。更多还原

【Abstract】 In both military and civil areas Strapdown Inertial Navigation System (SINS) plays such an important role as necessary equipment on vessels, planes, aircraft, and so on. In spite of many advantages such as independence, high precision and robustness, SINS has unavoidable disadvantages. The single use of SINS doesn’t meet the needs of practical application, because its traditional independent initial alignment requires a long period and static state. Furthermore, the error in pure inertial navigation system accumulates in the whole period in terms of IMU error, which results in not high enough precision. Thus, it has practical significance to research on characteristics of errors and integrated initial alignment based on SINS.In accordance with the principle of SINS, static and dynamic error equations are deduced and presented in detail. Then we made analysis on the characteristics of errors in static and motion states separately. Three major sources of error stimulate constant and periodic systematic errors, and the motion of vehicle changes the periods.To make clearer the influence of motion and different methods of integrated alignment on the performance and effect of initial alignment, we build several integrated math models with such different observed variables as velocity, position, velocity and position, velocity and attitude. Then we adopt three methods to analyze the observability and made simulations. Due to the differences of coupling degree of states, velocity and attitude mode has the best effect, position mode has the worst effect, velocity and position mode, velocity mode has the modest effect. Another, the fierce motion of vehicle can greatly enhance the observability, even break through the influence of gyro drifts on misalignment angles and increase the precision to a higher level.Considering the imponderable IMU error and low azimuth precision in static state, we bring forward a new method of double-position integrated alignment in the thesis. Simulation results show that such method can estimate gyro drift and azimuth misalignment angle precisely. At last, the availability of KF in integrated initial alignment is tested under static state and motional state through lab experiment. Compared with the traditional control theory, KF reveals its own superiority, thus has great value for practical application.更多还原