Gravity disturbance compensation for dual-axis rotary modulation inertial navigation system

Gravity disturbance compensation is an important technique for improving the positioning accuracy of high-precision inertial navigation systems (INS). Aiming at current problems resolution gravity background field and robustness algorithm are insufficient compensation. In this study, error frequency characteristics INS caused by disturbances investigated. The with a spatial 1’ × from satellite altimetry marine model preliminarily introduced into initial alignment pure calculation to implement dual-axis rotary modulation INS. Detailed results show that east affects north attitude, attitude in alignment. calculation, horizontal causes form Schuler oscillation. mainly affected its amplitude; however, can be ignored practice. addition, low-speed underwater vehicles, influence high-frequency signals on position shows increasing trend. Finally, effectiveness achieved altimeter confirmed dynamic shipborne test. maximally improved approximately 17.9% after compensated simultaneously