Rectangular-structure-based pose estimation method for non-cooperative rendezvous.

Pose estimation for spacecraft is widely recognized as an important technology for space applications. Many space missions require accurate relative pose between the chaser and the target spacecraft. Stereovision is a usual mean to estimate the pose of non-cooperative targets during proximity operations. In this paper, an accurate algorithm for pose estimation is proposed by taking advantage of the geometric structure of the object. With stereo cameras, our approach employs the corners of the solar panel as features and uses bundle adjustment to improve the accuracy. Simulation results demonstrate that our method improves the precision and robustness for non-cooperative spacecraft pose estimation. Our laboratory experiments further validate the approach. The results show that the rotation angle error of our method is within 0.8°, and the measurement error in translation is less than 0.4% at the distance from 3 m to 1.2 m.