一种基于CDKF的SINS/GPS紧组合导航算法

An Algorithm for SINS / GPS Tightly Integrated Navigation Based on CDKF

为解决SINS/GPS紧组合导航系统在SINS初始失准角较大的情况下精度下降的问题,提出一种基于欧拉角状态的中心差分卡尔曼滤波组合导航算法。Sigma点采样时,用欧拉角作为姿态参量,保证Sigma点采样过程中姿态参量与其他参量的同步;Sigma点沿系统方程传播中,转换为四元数表示,避免欧拉角姿态解算的高计算量和复杂超越方程的求解。通过仿真实验证明,提出的方法比加性四元数算法具有更快的收敛速度和更高的精度。

The accuracy of SINS/GPS integrated navigation system will decline when there is a large initial misalignment angle. To solve the problem, a navigation algorithm based on center difference Kalman filter was proposed. For the sake of the synchronization of the attitude parameters and other parameters in the process of Sigma point sampling, Euler angle was chosen as attitude parameter. In order to avoid high computation and the complexity of transcendental equation solving, Euler angles were switched to quaternions when propagate following the system equation. The simulation results show that the proposed algorithm has a higher convergence speed and accuracy than the additive quaternion algorithm.