Optical Flow as a navigation means for UAV

The paper considers various aspects of the use of the optical flow (OF) methodology in unmanned aerial vehicle (UAV) navigation. OF could gives estimates of the UAV velocities only, therefore its use on the one hand usually leads to an the errors growth in the UAV position estimation. This drawback is due to the presence of bias in the speed estimates. On other hand OF is probably the only navigation tool when there are no other estimates of UAV position available, for examle in GPS denied environment. Therefore it is necessary to approach very thoroughly to the OF and other navigation system elements data fusion. In this work the UAV landing problem on the basis of the OF usage with navigation system sensors is considered.