基于四元数法的捷联式惯性导航系统姿态解算研究

为实现捷联式惯性导航系统的精确导航，载体的姿态解算算法是核心技术之一。首先分析了欧拉法、方向余弦法、四元数法求解姿态矩阵的优缺点，根据四元数法与方向余弦法两种解算方法分别进行计算，两种方法的计算结果之差与理论真值比较以得到解算的相对误差，从而验证了四元数法的正确性和有效性，最后提出提高采样频率和采用高阶计算算法能进一步减小姿态解算误差。数字化仿真与转台试验结果表明，根据本文所述算法进行载体姿态解算的误差很小，具有良好的实时性，为捷联式惯性导航技术的工程实践提供了依据。

Study on Attitude Solution for Strapdown Inertial Navigation System Based on Quaternion Algorithm

To guarantee navigation precision of strapdown inertial navigation system (SINS), attitude solution for carrier is one of key technologies. We analysis strongpoint and defect of Euler algorithm, direction cosine algorithm and quaternion algorithm, firstly. Carrier attitude is compute separately according to quaternion algorithm and direct cosine algorithm, comparative deviation is obtained by contrasted these two solution deviation with theory result, therefore the validity of quaternion algorithm is proved. Increasing sampling frequency and adopting high-level compute algorithm is useful to monish compute deviation. Digital simulation and experiment results show that, the carrier attitude solution deviation is small by adopting this method, and it satisfies real-time needs for carrier self-navigation. The proposed attitude solution method offer an useful reference to strapdown inertial navigation technology applied in engineering.