Research On The Key Tecknologies Of Autonomous Deck-landing Of Unmanned Helicopter

Automatic landing on a ship is a fundamental function of an unmanned ship-basedhelicopter. Because parking space on a small or medium sized ship is very the limitedand the helicopter is always interfered by a very complicated cocktail wake flow whichis caused by the moving ship or a gust, landing on a small or medium sized ship is moredangerous than landing on a land or aircraft carrier. So, it is of great research value todesign a precise guiding system to assist the unmanned ship-based helicopter to land ona ship. As one of the guiding systems, computer vision guidance system is moreprécised and more robust, even at a lower cost.A computer vision guidance system is designed in this paper. After designed thestructure of this guidance system, we focus on how to design, recognize and track theassisting landing sign and how to use the assisting landing sign to position. The mainwork is as follows:1When the helicopter is going to landing on a landing platform, it will fly overthe platform first, then land on the platform. Based on the characteristics of the landingprocedure, the helicopter landing guidance procedure is split to two parts: guiding thehelicopter to the platform and guiding the helicopter to land on the platform. Becausesome parameters, which the airborne equipment can collect, can be used in the guidancesystems, such as the attitude angle of the unmanned helicopter, the attitude angles of thecamera and the focal length. We will use these parameters in our computer visionguidance system. For the sake of these imported parameters, the process of getting theguiding parameters will be simplified in the proposed guidance system. In this paper,the coordinate systems and their transformation relation which the computer visionguidance system will use are studied. In order to make the guidance system workrobustly, a novel auxiliary landing mark is designed. This mark not only can berecognized quickly, but also can afford enough guidance information even when it ispartly imaged.2In the stage of flying over to the landing point, Auxiliary landing mark’srecognition algorithm,tracking algorithm and getting the guiding information are also studied in this paper. The results of the experiment results show that the auxiliarylanding mark can be recognized easily, the tracking algorithm can work robustly Andwe can obtain guiding information effectively.3) In this paper, we also study how the wind and waves affects the ship’s motion.Under this affection, the landing mark will be imagined partly. When the mark is partlyimagined, according to the body of the mark is constituted by rings, we use a practicalalgorithm to get the center of the mark. After having gotten the center of the mark weuse this center data to design an imitated four-quadrant detector to guide the unmannedhelicopter to land. The result of the experiment of estimating the center of the partlyimagined mark shows that the center estimation algorithm is robust And we can obtainguiding information effectively.