自适应卡尔曼滤波在磁干扰姿态测量中的应用

The Application of Adaptive Kalman Filter to the Orientation Estimation of Magnetic Interference

针对姿态测量系统陀螺仪漂移、周围局部磁场干扰制约姿态测量精度的问题,提出一种基于四元数的自适应卡尔曼滤波(q-AKF)的方法。该方法利用陀螺输出建立姿态解算误差角的状态方程,以磁强计输出构造自适应测量噪声协方差矩阵。仿真结果表明,相比无损卡尔曼滤波(UKF)算法和扩展卡尔曼滤波(EKF)算法,采用q-AKF算法补偿得到的姿态角误差不大于0.5°。q-AKF算法对磁强计进行补偿,能够有效抑制陀螺的漂移误差,提高磁干扰环境下姿态解算精度,具有较高的工程应用价值。

Aiming at the problem that the accuracy of the orientation estimation is affected by the gyroscope bias error in the orientation estimation system and the interference from surrounding local magnetic disturbances, a quaternion-based adaptive Kalman filter （q-AKF） algorithm is proposed in this paper. The algorithm utilizes the gyroscope outputs to establish the state equation of attitude error angle and construct the adaptive measurement noise covariance matrix with the outputs of the magnetometer. The simulation results show that the attitude error angle obtained by the q-AKF is less than 0.5°compared with the UKF algorithm and the EKF algorithm. Using the q-AKF algorithm to compensate the magnetometer can effectively suppress the gyro bias error, improve the precision of attitude algorithm in magnetic interference environment, which has high engineering application value.