自主姿态测量算法研究

Study on the Algorithm of Independent Attitude Measurement

航姿系统一般不实时计算速度和位置信息,无法补偿地球自转和表观运动引起的分量误差,同时陀螺漂移较大,载体长时间持续机动时,出现姿态精度不高,甚至发散的问题。提出了一种基于卡尔曼滤波的姿态融合算法,将等效陀螺漂移列入系统状态,利用卡尔曼滤波的新息对运动状态进行判别,在一定条件下,用加速度计的输出作为量测量进行卡尔曼滤波的量测更新过程。实验结果表明,所提出的姿态融合算法考虑了陀螺漂移,能提高载体长时间机动时的姿态精度。

in attitude and heading reference system（AHRS）, the velocity and position information cannot be calculated in real time, the errors caused by the rotation and apparent motion of the earth are unable to be com- pensated effectively. In that case, the drift error of the gyro is accumulated continuously. Therefore, there are the low precision even divergence problems for the heading and attitude information during a long time flight. A fusion algorithm for attitude determination based on Kalman filter is proposed. The gyro bias is used as the Kalman state vector, motion state of the cartier is judged by innovations of the Kalman filter, outputs of acceler- ometer are used as observations to carry out the update process of the Kaman filter measurement. The results of experimentation verify that this fusion algorithm based on Kalman filter is capable to improve the attitude accu- racy of the system with consideration of the gyro drift.