俯仰/滚转耦合的大角度姿态测量算法

Pitch/roll coupled large-angle attitude measurement algorithm

摘要:

基于加速度计或陀螺仪的测姿方法均存在大角度条件下姿态角误差放大、突变问题。对大俯仰角测量，通过预置欧拉旋转法可确定冗余加速度计的布置方式，降低了俯仰角测量误差。对大俯仰角条件下的滚转角测量，提出基于角速率阈值判定的陀螺解耦测姿算法。当俯仰角速率大于设定阈值时，采用角速度投影可钳制滚转角误差的漂移；当俯仰角速率小于设定阈值时，采用角速度积分可避免角速度投影造成的姿态误差放大。通过理论推导、分析和仿真，预置欧拉旋转法能有效避免大俯仰角条件下俯仰角姿态误差放大，陀螺解耦测姿算法能在振荡环境下长时间保持滚转角精确度。

Abstract:

Under large-angle conditions, the problem of amplification or even mutation of attitude error would arise in the attitude measurement methods based on accelerometers or gyroscopes. For the large pitch angle measurement, the arrangement of redundant accelerometers can be determined by preset Euler rotation method, which reduces the pitch angle measurement error. For the roll angle measurement under the condition of large pitch angle, a decoupling attitude determination algorithm based on angular rate threshold is proposed. When the actual pitch rate is greater than the threshold value, the angular velocity projection method can suppress the drift of the roll angle error. When the actual pitch rate is less than the threshold value, the angular velocity integration method can avoid the enlargement of the attitude error caused by angular velocity projection. Through theoretical derivation, analysis and simulation, the preset Euler rotation method can effectively avoid the amplification of the pitch angle attitude error under the condition of large pitch angle, and the gyro decoupling attitude measurement algorithm can maintain the roll angle accuracy for a long time in an oscillating environment.