Control of Hover for a Micro-Air-Vehicle using a Visual Snapshot

The problem of developing a reliable system for sensing and controlling the hover of a Micro Air Vehicle (MAV) using visual snapshots is considered. A new algorithm is proposed that uses a stored image of the ground, a snapshot taken of the ground directly under the MAV, as a visual anchor point. The absolute translation of the aircraft and its velocity are then calculated by comparing the subsequent frames with the stored image and fed into the position controller. For controller design and testing purposes, we analytically derive a complete model of a small size helicopter with no stabilizing bar (flybar). The simulation results for 2D and 3D versions of the snapshot algorithm confirm the effectiveness of the proposed algorithm.