针对MEMS惯性测量单元,通过分析方向余弦矩阵的特性,设计了基于非线性状态观测器的水平姿态解算方案,并证明了该算法的稳定性。在此基础上,提出了一种基于Kalman滤波算法的解决方案:利用陀螺仪输出构造系统方程,利用匀速条件下的加计输出构造量测量,并通过双重模值判别机制自动判别量测信息的有效性,最终实现了MEMS姿态信息的融合解算。静态实验和角运动、线运动干扰实验表明:该算法可以得到稳定有效的水平姿态,误差<1°。

For MEMS-based inertial units, a scheme for horizontal attitude estimation based on nonlinear state observer is proposed by analysing the direction cosine matrix, then the stability of the algorithm is proved. On this basis, a practical scheme based on Kalman filter is designed whose system equation derived from MEMS gyros outputs and measurement constructed by accelerometers outputs in uniform motion. A so-called double model value mechanism is designed to automatically identify whether the measurement information is effective. The algorithm has been evaluated by static dynamic and interference experiments, and the results show that it can successfully produce stable and effective horizontal attitudes and estimation error is within 1°.