Research On Mobile Coverage Scheme Of Multi UAVs In Open Area

In the past decades,the unmanned aerial vehicle had a tremendous development due to its advantages of high mobility,low communication cost and no need to risk pilot’s life.It was first used in the military field to perform tasks including jamming the enemy,reconnaissance of the enemy,precision strike and so on.With the development of UAV towards miniaturization,the cost of UAV is also reduced,and the controllability is improved.Instruments and equipment such as GPS,radar,laser,and sonar can be modularly equipped on UAVs,which makes UAV technique gradually penetrate from the military field into other application fields,such as communication coverage,disaster monitoring,logistics and transportation,search and rescue,etc.In the application in the above fields,the ability to cover the whole area and to detect the abnormal points in time is very important.In this thesis,the following work is done for the complete coverage path planning problem of UAV coverage in the open area and the access problem of abnormal points found in the coverage:(1)This thesis proposes a new complete coverage path planning method,which is inspired by the cell division method used in wireless cellular communication,and combines the graphic segmentation method of regular hexagon and the characteristics of high-altitude long endurance UAV.Compared with other methods,the absolute blind area is eliminated,and the longest revisit time of the temporary blind area is reduced.The path design can prevent some malicious targets from sneaking in stealthily by obtain the UAV’s flight path plan through intelligence means,also reduce the time consuming of achieving the complete coverage.The superiority of the scheme in eliminating blind areas and other fields is proved through theoretical calculation,and then the force and energy loss of the aircraft during the turning process are analyzed.Comparing with other design schemes,due to the large turning radius designed in this scheme,the energy losse per unit mileage caused by the turning of the scheme is about 10 to the power of-6 times of the lifting resistance.Therefore,the energy consumption of this scheme design is at an acceptable level,which is economically viable.(2)After the target points are found in the open area,each target point needs to be probed one by one with higher precision or the corresponding tasks are executed.Since different target points may have different task priorities,for multiple target points The problem of continuous exploration of target points can be regarded as a traveling salesman problem.In this thesis,the extended ant colony optimization based on mixed feedback mechanism is improved,and the priority is added using low priority penalty for the target node,so that it has the ability to make overall planning for targets with different priorities.The average target access cost of different points of different priorities is used as the individual fitness function to optimize the artificial selection of the chromosome exchange stage combined with the genetic algorithm in the extended ant colony optimization based on mixed feedback mechanism.In order to reduce the algorithm operation time,the artificial selection failure probability is designed,which can reduce the running time of the algorithm to a certain extent.The algorithm is simulated by computer.Compared with other planning algorithms,due to the randomness of the ant colony algorithm itself,the algorithm needs to be run many times to obtain the average value and the variance of the result.The improved algorithm has obvious advantages in reducing the individual fitness function,and improve the stability of the algorithm output results.The research studied in this thesis can provide new design ideas for complete coverage path planning and it is of positive significance for using heuristic algorithms such as ant colony algorithm and genetic algorithm to solve the problems in communication network.