A Fast Recognition Algorithm for Detection of Foreign 3D Objects on a Runway

Abstract. !The systems for detection of foreign objects on a runway during the landing of an aircraft are highly demanded. Such systems could be installed in the airport or could be mounted on the board of an aircraft. This work is focused on a fast foreign object recognition algorithm for an onboard foreign object detection system.

The algorithm is based on 3D object minimal boundary extraction. The boundary is estimated through an iterative process of minimization of a difference between a pair of orthophotos. During the landing an onboard camera produces a sequence of images from which a number of stereo pair could be extracted. For each frame the runway lines are automatically detected and the external orientation of the camera relative to the runway is estimated. Using external orientation parameters the runway region is projected on an orthophoto to the runway plane. The difference of orthophotos shows the objects that doesn't coincide with the runway plane. After that the position of the foreign object relative to the runway plane and its minimal 3D boundary could be calculated. The minimal 3D boundary for each object is estimated by projection of a runway region on a modified model of the runway. The extracted boundary is used for an automatic recognition of a foreign object from the predefined bank of 3D models.