High-precision stradown inertial navigation algorithm based on ground velocity split

In traditional strapdown inertial navigation algorithm, the specific force integral term is solved by using a first order approximation method, and the approximation errors' influence on high precision applications can not be ignored. In order to eliminate the approximation errors, an improved strapdown navigation algorithm is developed in this paper. The ground velocity projected in the inertial frame is split into specific force ground velocity and gravity ground velocity. By deriving an analytical formula able to completely compensate the dynamic errors for the specific force integral term, we obtain the exact solution for the specific force ground velocity. By using the same method in solving the gravity ground velocity, we develop an improved strapdown inertial navigation algorithm with high precision under the implementation framework of traditional navigation algorithms. The improved navigation algorithm has overall performance advantage, and its navigation accuracy equals to that of dual quaternion navigation algorithms, but its real-time performance is about the same as traditional navigation algorithms.