Image-matching navigation method and apparatus for aerial vehicles

摘要

A method and apparatus for estimating the position and attitude of an aerial vehicle transiting over terrain through a combination of steps combining image registration and the inherent image coordinate system of the camera. The aerial vehicle captures an image of the terrain and extracts features from the camera image and pre-existing aerial imagery, and determines a perspective transform between the images. Image reference points are projected with the 2D perspective transform and an elevation map provides estimated 3D coordinates of the image reference points. Subsequently a camera position and orientation necessary for the camera to obtain the initial camera image is determined by projecting reference points with locations defined by the image coordinate system of the camera to define terrain points, and conducting an optimization to minimize displacements between the estimated coordinates and the terrain coordinates. The estimated camera position provides a location and attitude for the aerial vehicle.