抗光轴扰动的双目视觉测量方法

Correction of Optical Axis Disturbance for Binocular Vision

针对交会对接过程中双目测量相机受空间环境影响其光轴指向发生扰动的问题,提出一种抗光轴扰动的双目视觉测量方法。通过辅助光路将固定于卫星本体的参考标志分别成像于两侧像面的边缘,根据其图像变化估计光轴扰动变换矩阵,补偿因光轴扰动而产生的像面变化,从而实现抗扰动测量。理论推导表明:只要参考标志位于两侧相机视场内,便能够校正相机光轴扰动。利用地面试验平台进行了光轴扰动校正的仿真试验,试验结果表明:当两侧相机光轴存在扰动时,该方法能够有效校正光轴扰动,极大地提高了三维位置的测量精度。

In rendezvous and docking, camera optical axis suffers from disturbances due to the influence of complex space environment. A correction method of optical axis disturbance for binocular vision is presented. The light from a reference marker fixed in satellite frame enters the field of view of each camera through the auxiliary light path, providing infinite reference points for each camera. According to image variation of the reference marker, transformation matrix of optical axis disturbance is estimated and then used to compensate camera attitude change. Theoretical derivation shows that as long as the reference marker remains in the field of view of each camera, the proposed method can correct three-axis disturbances of optical axis. Experiments are carried out to validate the proposed method utilizing a ground testing platform. Simulation experimental results show that the proposed method can effectively correct optical axis disturbances and greatly improve three-dimensional measurement accuracy of binocular vision.