基于路标观测角的星际着陆器自主位姿确定技术

Autonomous Position and Attitude Determination for Interplanetary Landers Based on Landmark Observation Angles

针对利用导航路标进行六自由度状态估计这一非线性、模糊性问题,对星际着陆器自主位姿确定技术进行了研究。为了减小算法的复杂性,提高求解精度,基于欧式变换下角度不变性,提出以导航路标观测视线之间所形成的夹角作为观测量,对像素观测方程中位置、姿态状态进行解耦求解。通过对观测矩阵的讨论,分析了导航路标空间分布对位姿确定精度的影响,给出了导航路标选取的最优观测方案。最后利用蒙特卡罗仿真对所提导航算法进行了验证,并对影响导航精度的各相关因素进行了分析。

To deal with the non-linear and non-unique question of six freedom states estimation using the pixels of navigation landmarks,the autonomous position and attitude determination for interplanetary landers is discussed. Based on the invariability of angles in orthogonal transformation,the position and attitude are decoupled for determination by importing the observation angles between of measured lines of sight so as to reduce algorithmic complexity and improve solution precision. For the optimal observation questions,an observation matrix is utilized to analyze the effect of landmark geometry configuration on determination precision,and a novel landmark selecting scheme is proposed to improve the precision of state estimation. Finally,the autonomous optical navigation algorithm is validated and the factors influencing navigation precision is analyzed using Monte Carlo simulations.