航天器交会对接中摄像机内参数在轨标定算法

An Algorithm for Determining Intrinsic Parameters of Camera in Spacecraft Rendezvous and Docking

针对航天器交会对接过程中位姿参数的测量问题,本文考虑到飞行器在轨运行期间,CCD相机受空间环境的影响,其内参数会发生变化的实际情况,提出航天器交会对接中摄像机内参数标定的线性方法。其主要特点是摄像机只需拍摄三幅光标点图像,无须知道该组光标点的任何几何信息。通过计算圆环点,建立绝对二次曲线对摄像机内参数的约束方程即可线性求解摄像机内参数。仿真实验表明,该方法在航天器交会对接中,使得摄像机内参数的标定具有简便、实时和鲁棒性强的特点。

For measurement problems of attitude and position parameters in the process of rendezvous and docking for spacecrafts, changes of intrinsic paramelers of the camera mounted on the spacecraft in orbit under the influence of space environment are taken into account. A linear method is proposed and its main feature is in that the camera only shots three cursor images, without needing to know any geometric information of the group of the cursor points. By calculating the geometry of circle points, and establishing the constraint equations of the absolute conic on the camera intrinsic parameters, camera intrinsic parameters can be solved linearly. Simul,.tion experiments show that the method is effective in the rendezvous and docking for spaeecrafts. The calibration of camera intrinsic parameters has simple, real-time and robustness features.