The Study On The Mountain Search Method By Unmanned Aerial Vehicles(UAV)

With the development of economy,aviation industry in China is marching forward at a high speed,air traffic and aviation enterprises also increasing gradually,and the number of aircraft is growing fast.In this way,aviation security is worthy of studying and needs to be emphasized.Aircraft accident is difficult to completely avoid,and efficient aircraft search scheme becomes an important way to reduce the loss of life and property of the aircraft accident and to negative impact.In recent years,unmanned aerial vehicle(UAV)industry develops rapidly;UAV has been widely used in military,agriculture,geology and meteorology etc.When this device is applied to search aircraft that crashes in the mountains,it goes with the advantages of a low cost,small space restriction and no casualties etc.Combining two focal points and hot issues about the “efficient search” and UAV,this thesis studies the UAV mountain search method.This study selects a model suitable for the search in mountainous areas,uses the digital elevation model and computer technology to generate contour block map of the search area,studies the height of aerial photograph of the UAV in mountains search,on the basis of the height of aerial photograph,this thesis establishes a search level.With the reference of helicopter mountain search safety redundancy,concerning the mountain slope,this study establishes the UAV mountain search safety redundancy;on this basis,this thesis selects key search points on the contour block map,and then abstracts the key search points to adjacency matrix,which leads the UAV to avoid obstacles formed by the mountains,thus calculates the shortest path of flying over all the key search points by genetic algorithm,simulated annealing algorithm and ant colony algorithm respectively.Through the calculation and the simulation results of MATLAB,the study compares among the search path length,algorithm stability and running time of various algorithms;then finds path planning optimization algorithms which apply to the UAV mountain search;Based on reconstructing the scope of the crash of a rescue helicopter crash of Wenchuan earthquake in 2008,this thesis combines theories with practice,analyzing and illustrating the theory of UAV mountain search method.By using remote sensing technology,the search range has been divided into the surface,empty valley and the obstacles of valley,which aims at the three different areas and develops the search scheme respectively.The experiments are conducting through measuring different diameters of the search level of mountain by remote sensing technology and determining the method of surface search.Firstly,researched the mathematical model of sector search,extended square search;secondly,established mathematical model of “?” search;thirdly,compared search path length of three search pattern in the same scope,sum up the most efficient way of unmanned aerial vehicle(UAV)searching,thus to establish the method of empty valley.By utilizing the path planning optimization algorithms which apply to the UAV mountain search,the thesis establishes the search method of various obstacles valley.