Non-damping system reset schemes for underwater SINS based on intermittent calibration information

Abstract

For Strap-down Inertial Navigation System (SINS), the estimation accuracy of gyro drifts in system reset is subject to the steady state horizontal attitude errors induced by accelerometer biases. Two non-damping system reset schemes are proposed to solve this problem. First, the Doppler velocity log (DVL) aided parameter estimation method is derived to estimate the accelerometer biases and equivalent horizontal attitude errors; then the P equation of system reset is reformulated in which the horizontal attitude errors are considered and obtained through the parameter estimation method; finally, on the basis of P equation, with intermittent calibration information, two system reset schemes are designed. Simulation results indicate that by compensating accelerometer biases before system reset, the proposed schemes have higher estimation accuracy of gyro drifts, meanwhile they reduce the time of using DVL and have better error suppression performance than existing schemes.