Research On Flight Control And Target Location Technology For An Unmanned Reconnaissance Aerial Vehicle

The Unmanned Aerial Vehicle (UAV) has been used in a wide range of applications area, particularly in the military missions, its value and importance has been attached great importance to scholars at home and abroad. Related researches, such as the navigation, flight control, target location, and et al, has always been a hot spot in theoretical study and applied research fields. In this thesis, the autonomous flight control strategies and the target location methods has been researched, for the actual needs of a military URAV carrying out low-altitude reconnaissance missions.Firstly, the related research status and the key technology difficulties of the autonomous flight control and the target location for URAV are analyzed, and the mechanism model for the URAV flight attitude control and the target location system was built up, according to the special functional requirements of a military URAV which should complete low-altitude reconnaissance tasks.Secondly, a variable universe fuzzy PID control method fitting for the URAV to achieve autonomous flight control has been proposed. This method takes into account issues such as the strong time-varying characteristics in UAV control process and the existence random disturbance. Meanwhile, it also considered the special circumstances where the established control system should not be too complicated because of the small size and the simple system configuration of URAV. A variable domain fuzzy self-tuning PID controller has been designed and some control strategies and rules have been established. The simulation researches about URAV flight along the preset orbit have been done as examples to verify the feasibility and validity of the proposed variable universe fuzzy PID control method for URAV the autonomous flight control. The proposed method has also been compared with conventional PID and fuzzy PID control strategy via a lot of simulation studies, and satisfactory results have been achieved.Finally, to solve the problem that traditional method could not work when there are not available topographic map or reliable reference, a new active target location method was proposed based on GPS and target positioning technology. The method could identify ground targets coordinate positions only on the basis of the ground targets image information taken by the camera and some necessary parameters of the camera system. An example to calculate the 3D positions of a ground target has been given to illustrate the working process of the method.