چكيده به لاتين
Unmanned systems have been the subject of interest to researchers for several decades and their applications are expending in military and civilian areas. Autonomy and cooperation are two characeristics which improve the capability of these systems and provide various applications. The objective of this thesis is to design and simulate the cooperative guidance algorithm for autonomous UAVs in order to track a dynamic target and lead it to a desired position. First, a mathematical formulation is developed to represent the area of operation that contains various types of threats, obstacles, and restricted areas, in a single framework. The autonomous guidance strategies are developed by using a rule-based expert system approach with the requirements of completing assigned mission or task, avoiding obstacle/restricted-areas, minimizing threat exposure level, considering the dynamic and communication constraints of the UAVs and avoiding collision. Cooperation of multiple UAVs is modeled by minimizing a cost function, which is constructed based on the level of threat exposure for each UAV and distance of each UAV relative to the target. This improves the performance of the system in the terms of increasing the total area of coverage of the sensors onboard the UAVs, increasing the flexibility of the UAVs to search for better trajectories in terms of obstacle/restricted area avoidance and threat exposure minimization, and improving the estimation by providing additional sources of measurement. Based on a variable polygon formation a cooperation strategy is designed to avert the target to the trackers desired position. Finally, the performances of the algorithms are evaluated in a MATLAB simulation environment, which includes the dynamics of each vehicle involved, the models of sensor measurement and data communication with different sampling rates, and the discrete execution of the algorithms. The simulation results demonstrate that the proposed algorithms successfully generate the trajectories that satisfy the given mission objectives and requirements.
