小型尾坐式飞行器航姿参考系统

针对小型尾坐式飞行器姿态实时解算问题,研究了低成本的航姿参考系统(AHRS).由于MEMS惯性器件精度较低,设计了混合卡尔曼滤波器,以姿态四元数和陀螺随机漂移为状态变量,抑制了载体长时间飞行时陀螺漂移造成的累积误差.由于加速度计输出值在除重力加速度之外的附加加速度较大时不可信,完善了判断载体运动状态的方法,根据加速度计的实际输出,选择加速度值或者磁场强度作为观测量.实验结果表明,设计的算法在精度和计算效率方面都能满足控制系统的需求,更加适用于对实时性有较高要求的飞行器.

AHRS of Small Tail-Sitter Aircraft

For real-time attitude estimation of small tail-sitter aircraft,a low-cost attitude and heading reference system(AHRS) is studied.Because of the low precision of MEMS inertial sensors,a kind of mixed Kalman filter is designed.Quaternion and gyro random drift are regarded as state variables,which suppresses the cumulative error caused by gyro drift during a long time flight.Due to the incredible output of accelerometer when the additional acceleration except gravitational acceleration is large,the method of judging carrier motion situation is perfected.According to the actual output of accelerometer,acceleration or magnetic field strength is chosen as the observed quantity.Experiment results show that the composed algorithm can meet the requirements of control system in terms of accuracy and efficiency.So,it is more suitable for aircrafts requiring high real-time performance.