轻小型飞行器在飞行中卫星导航失效时,余度控制回路要求导航系统具有自主确定姿态的能力。提出了基于IMU的输出确定水平姿态的方法,并采用UKF实现飞行中的实时滤波估计。对某无人机实际飞行的MEMS型IMU数据进行了仿真,结果表明该方法给出的姿态角信息满足控制精度需求。将UKF与EKF滤波估计结果进行比较,UKF更具有优越性。 Light-weight aircraft in flight satellite navigation fails, the redundancy control loop requires the navigation system has the ability to determine the attitude of autonomy. The method of determining the horizontal attitude based on IMU output is proposed, and the UKF is used to realize the real-time filtering estimation in flight. The simulation results show that the attitude angle information given by this method satisfies the control accuracy requirements. UKF and EKF filter estimation results are compared, UKF more advantages.