A rapid and accurate transfer alignment method using inertial instrument measurement information

The rapidity and precision of transfer alignment impacts the response speed and working precision of inertial navigation system (INS) directly, and flexural deformation is a critical constraint on transfer alignment performance. However, transfer alignment performance of the traditional modeling estimation method is easily degraded by the effect of model mismatch. Therefore, a rapid and accurate transfer alignment method using inertial instrument measurements is proposed in this paper. The relative attitude of main/sub INSs is roughly estimated by angular velocity measurements. Then, a novel transfer alignment filter model is established by relative attitude error model, and measurements of inertial instrument are used to construct angular increment matching and specific force matching quantities. This approach improves both the rapidity and precision of sub INS's alignment. The performance validation results indicate that compared with traditional methods, the proposed method can improve alignment accuracy by more than 70% and significantly shorten alignment time, thus realizing rapid and accurate alignment.