微小卫星姿态确定系统设计.doc

摘 要 相对于昂贵、大型的卫星而言，微小卫星因其成本低、性能高、方便灵活、研制周期短、发射灵活等优点，而日益受到人们的重视和应用。卫星的姿态确定是进行卫星的姿态控制的前提，是星载仪器正常和有效工作的重要保证。本文以某太阳同步轨道卫星的姿态确定方案设计为背景，较为详细地研究了三轴对地观测卫星的姿态确定系统的设计。本文的主要工作如下： 1）经过大量技术调研，概述了微小卫星的组成和特点，微小卫星的发展现状以及微小卫星未来的发展趋势。 2）全面、系统的总结了各种姿态描述方法，坐标及坐标转换关系，采用四元数与欧拉角的描述方法建立了卫星姿态的运动学模型。概要阐述了几种姿态确定算法的基本思想，并着重阐述了广义卡尔曼滤波的基本过程。 3）基于“陀螺+太阳敏感器+磁强计”的的姿态确定系统的设计，应用广义卡尔曼滤波技术设计了卫星姿态的运动模型。采用四元数法建立了较完整和准确的姿态估计器模型，通过采用广义卡尔曼滤波（EKF）算法仿真证明此姿态确定算法能够对星体姿态进行较精确的估计或校正, 满足卫星控制精度要求。 4）分析了陀螺测量噪声，仿真步长及初始状态协方差估计对卡尔曼滤波收敛时间和滤波精度的影响并得出了相应的一些结论。 关键词：微小卫星，姿态确定，广义卡尔曼滤波 Abstract Comparing to the expensive satellites with large-scale, the small satellites are more popular and applied by the designers because of their low cost, high performance, short development period and more flexibility to the large satellites. In the satellite design, the precondition of attitude control is the attitude determination and that ensures the onboard equipment work normally and efficiently. This paper, taking a specific sun synchronous orbit satellite as an example, studies systematically and all-around the design and realization of the attitude determination system for a three-axis stabilized satellite for Earth Observation. The main work done is as follows: 1) Through the many of technical investigation and analysis, the constitution and characteristics of the small satellite attitude are summarized. This paper firstly describes the current situation and development trend of the small satellites. 2) Several kinds of attitude description methods, coordinate and coordinate transformation are generalized roundly and systematically. The kinematics model of satellite is constructed with using of description method of quaternion and Euler angle. The basic idea of several attitude determination algorithms are concluded, and the basic process of extend kalman filter is introduced in detail. 3) Based on the attitude determination system consisting of gyroscopic, magnetometer and solar sensing device, attitude movement model are