Attitude updating algorithm of SINS and composite application

The real-time attitude computation is key to the accuracy of Strap-down Inertial Navigation System (SINS). This paper discusses the attitude updating quaternion algorithm of SINS and the quaternion recursive algorithm based on the third-order Taylor expansion. In order to reduce the influence of the non-commutative error caused by quaternion algorithm in high dynamic circumstances, we present a rotation vector algorithm that compensates for the deviation of the nonreciprocal angular velocity vector, whose pros and cons of the algorithms are analyzed. The rotation vector method can effectively reduce the non-commutative error at certain sampling frequencies. Moreover, a maneuverability criterion is designed for determining the dynamic level, Based on which the composite pattern containing two algorithms are proposed for flying submunition missiles.