INS/CNS Integrated Calibration based on Speed Reference Information

Abstract

CNS needs INS to provide horizon attitude information as the horizon reference. The non-damping INS on critical conditions is easy to cause error fluctuation and divergence when the accelerometer zero is changed, directly affecting horizon reference information precision of assistant CNS. Therefore, under on-board use conditions, the INS short-term high-precision characteristics are used in CNS/INS/LOG integrated system to design Kalman filter with horizontal speed damping and compensate dynamic error of INS. The calibration and readjustment technology of on-board CNS/INS integrated system is based on horizontal speed damping. The accurate reference information of CNS is used to finish correction of position error, misalignment angle and main gyro drift error. In this way, the readjustment period will be extended to realize long-time and high-precision navigation of the integrated system.