旋转弹导航系统研究

A Navigation System for Spinning Projectile

旋转弹自转角速度大,由陀螺仪和加速度计组成的传统导航系统难以应用,提出用微小型加速度计构成无陀螺微惯性测量单元GFMIMU(Gyroscope-Free Micro Inertial Measurement U-nit)为旋转弹提供完整的导航信息。根据无陀螺的测量原理,充分利用多个加速度计的冗余输出信息构建自滤波系统,抑制GFMIMU角速度误差的快速发散。为克服GFMIMU长时间工作姿态角误差的积累,采用磁强计与其进行组合导航;从解算精度与实时性考虑,基于四元数描述建立了该组合导航系统的状态方程和观测方程,并采用二阶插值滤波器进行信息融合。最后,对所设计的组合导航系统进行系统仿真,仿真结果验证了该系统设计方案的可行性。

It is difficult to use a traditional navigation system composed of gyroscope and accelerometer for navigating spinning projectile having high angular velocity. A gyro-free micro inertial measurement unit （GFMIMU） composed of micro accelerometers only was put forward to provide all of navigation information for spinning projectile. Based on GFMIMU measurement theory, a self-filter system was built up using the redundant output information of accelerometers, which suppresses accumulative angular velocity error increasing quickly. To decrease the accumulative angular errors of GFMIMU, a scheme of a navigation system integrated a GFMIMU and a three-axis magnetometer was adopted. The state equation and estimation equation of the system were built up using quaternion. Considering the accurate and real-time filtering of the system, a second-order interpolation filter was proposed to process information fusion. A simulation of the system was made. The simulation results show that the scheme of the proposed design is feasible.