基于Sigma-point卡尔曼滤波的INS/Vision相对导航方法研究

针对无人机编队常用的leader-follower(领航-跟随)飞行模式,提出了一种考虑视觉导航设备输出时间延迟问题的INS/Vision相对导航方法,给出了leader与follower之间的相对惯导方程以及相对视线矢量测量原理.由于INS/Vision相对导航系统是一个强非线性系统,采用Unscented卡尔曼滤波融合相时惯导信息和相对视线矢量信息,从而估计出leader与follower之间的相对位置、相对速度和相对姿态,受姿态四元数的归一化限制,在滤波中采用罗德里格斯参数作为姿态误差状念,对于视觉导航系统量测量存在时间延迟的问题,给出了延迟后的量测量与当前惯导信息融合的方法,最后通过仿真研究证明了方法的有效性.

Research on Relative Navigation Method Based on INS/Vision Using Sigma-Point Kalman Filter

According to the leader-follower flight mode of unmanned aerial vehicle, the relative navigation method based on INS/Vision is presented considering the measurement of vision navigation equipment with time delay. The relative inertial equation and line of sight between leader and follower is derived. Because of the strong nonlinearity of INS/Vision relative navigation sys-tem, the unscented kalman fiher is used to estimate the relative position, relative velocity and relative attitude by fusing the relative inertial information and line of sight. For the quatemion normalization, an unconstrained three-component vector is used to pre-sented an attitude error quaternion. For the time delay problem of vision navigation equipment, the method of fusing the inertial navigation information and the measurement with time delay is provided.