Transfer Alignment In Warship Missile Strapdown Inertial Navigation Systems

With the development of the modern battle, most warship weapons that the inertial navigation systems are their main navigation equipments produce. These warship weapons have played important rules in modern battle. As warship weapons are launched on warships, the fast and accurate transfer alignment of SINS on moving warships becomes a crucial technique.Concerning the transfer alignment of SINS on a warship missile, the following crucial technologies were investigated in this paper:(1) Based on a unified approach to inertial navigation system error modeling, two SINS error models in warship missile transfer alignment were deduced respectively.(2) Dimension effect Error is one of the major error sources of transfer alignment of SINS,which is due to the deviation distance between the position of accelerometers and rocking center of ship. This paper discussed the theoretical principle of dimension effect, and the dimension effect error formula was deduced. At the same time, an online compensation method based on Kalman filter was proposed. The results of simulation showed that this new method was simple, effective and had widely practical value.(3) For verifying the effective and applicable range of the attitude change match method, Simulations were made on warship missile SINS under the condition of three sea wave models. Simulation results showed that the slave inertial system's misalignment angle could reach an anticipated precision in a short time. With the increasing sway frequency and range, estimated precision of misalignment angles would be raised further. The study verified attitude change matching could quicken convergence speed, increase estimation accuracy, need no maneuvering, and had strong availability.(4) Three transfer alignment approaches to SINS on warship missiles were compared by simulations.