The updating algorithm of Strapdown matrix is one of the crucial techniques of SINS. There are several kinds of attitude updating algorithms of SINS,such as direction cosine algorithm and quaternion algorithm.

• 捷联矩阵更新算法是捷联系统的关键技术之一，捷联惯导系统姿态算法有欧拉角法、方向余弦法、四元数法和圆锥补偿算法等几种方法。