Before revision: Point Cloud Registration is a fundamental problem in robotics and computer vision . Due to the limited accuracy in the matching process of 3D keypoints, the presence of outliers, probably in very large numbers, is common in many real-world applications  .
After revision: Point Cloud Registration is a fundamental problem in robotics and computer vision , which aim to estimate the rotation and the transformation between the 3D keypoints, the presence of outliers, probably in very large numbers, is common in many real-world applications .