A Novel Method for Gyro Bias Estimation of On-Board Inertial Navigation System Prior to Launch of Autonomous Drone
Yang Pang, Ningfang Song, Qingzhong Cai
Abstract
In this article, the attitude of the master inertial navigation system (INS) installed on the autonomous drone launcher and the slave INS installed on the autonomous drone are correlated by means of establishing a time-varying model of the relative attitude. And the coupling processes of the initial attitude error of slave INS and its gyro bias are modeled in the relative attitude. Then, according to the different characteristics of the two error coupling modes, the two types of error are decoupled by the equivalent rotation vector and the higher order small terms neglected, and the nonlinear dynamic accumulation model of the gyro bias of slave INS is established in the navigation coordinate system. Next, the linear accumulation model of the gyro bias of slave INS is obtained in its own coordinate system by multiplying the dynamic accumulation amount with the attitude matrix in real-time. Finally, the gyro bias of slave INS is estimated by means of the least squares algorithm. Simulation experiments show that the proposed method can estimate more than 80% of the gyro bias of slave INS. The results of the vehicle-mounted experiment show that the compensation of the gyro bias of slave INS leads to a significant decrease in the accumulation rate of the relative attitude error over time.