Optimal algorithm of attitude matching in transfer alignment

Four kinds of attitude matching algorithms used in transfer alignment are derived, the advantages and disadvantages of the four algorithms are presented, and the optimal attitude matching algorithm (OAMA) is presented and proved. Firstly, the traditional attitude matching algorithm attitude angle matching algorithm (AAMA) and the improved algorithm attitude matrix matching algorithm (AMMA) are introduced. Then, the measurement misalignment is introduced, which is the product of the attitude matrixes of the master inertial navigation system (INS) and the slave INS, then the measurement misalignment matching algorithm (MMMA) is derived. The above three attitude matching algorithms are derived on the condition that the mount angles of the slave INS are small. Finally, the MMMA is improved which is more suitable when the multiple ejector racks are used to carry more weapons, and the improved MMMA is called OAMA. The relationships among four kinds of algorithms are proved in theory. The velocity plus attitude matching method is used in the simulation study of transfer alignment, and the results show that the four proposed algorithms have the same precisions when the input condition is same, and that the OAMA can be used in the condition when the mount angles of the slave INS are larger angles, which is more suitable for modern wars.