Ground Target Location And Route Design Method Using Fixed-Wing UAV

Currently,UAV is very widely used in the military and civilian range,for different tasks and different functions,it develops a wide range of UAVs,which marking the unmanned aerial technology get into a big boom.In such background,the practical application of UAV,especially the application of small unmanned aerial vehicles has become a popular research direction,by the community wide attention.The precise positioning of UAVs on the ground is a key problem in the practical application of UAVs.It will directly affect the quality and efficiency of UAV missions,and even determine the completeness of tasks.The research on the precise positioning of visible targets by unmanned aerial vehicles(UAV)is of great significance to improve the application value of small unmanned aerial vehicles(UAVs)and promote their practical application.In order to solve the problem of low positioning accuracy of small UAVs,a high precision positioning method of single-point and multi-point observation and positioning is proposed in this paper.Firstly,based on the previous research,the traditional single-point angular positioning method was modeled and solved,and sensitivity analysis of three-axis attitude angle and two-degree-of-freedom PTZ angle which affect the positioning accuracy was carried out.The relationship between the position of the target point in the image and the angle of the optic axis is solved,and the optimal positioning area in the image is determined by giving the error of the viewing angle.Aiming at the problems of single point positioning,such as angle measurement error and unknown altitude,a positioning model is established,and the information of the height and position of the target point is estimated by using multi-point observation and multiple line-of-sight intersection points.A new method of multi-point localization based on the least squares method is proposed.The unbiased estimation of the state quantity is carried out.The more the number of observation points are,the more the positioning results converge to a certain group The simulation results show that the method can achieve high positioning accuracy.Aiming at the problem of the deviation between the positioning result and the actual position,an error correction method based on the apparent motion analysis of the target is proposed.The target-aircraft system model is established to analyze the correspondence between the target position,the aircraft position and the deviation,and the analytic expression of the apparent coordinate is solved by using the spatial analytic geometry knowledge.Aiming at the problem that the visual coordinate expression is complex and difficult to solve the analytical expression of the apparent trajectory curve,the visual trajectory of the target is simulated and analyzed to analyze the influence of the position and attitude angle on the trajectory.The corresponding relation between the trajectory and the deviation is analyzed,the corresponding judgment rule and calculation method are determined,and the deviation amount is determined to be corrected.Considering the irregular trajectory caused by the irregularity of the flight path in practical application,the correction of the apparent coordinates is made by the correction of the roll angle and the correction of the aircraft position so as to present the standard visual trajectory.The error correction accuracy can reach 0.01 m.This paper proposes a route design method based on positioning error analysis.The effect of the visual angle error on the positioning accuracy under different flight heights and flight radii is studied,and the optimal altitude and radius are taken as the mission route index.According to the relationship between the apparent trajectory and the UAV mission trajectory,the paper analyzes the readability of the trajectory under the circular and quadrilateral routes,and determines the main basis of the circular route as the positioning route.The flight experiment outline was designed to validate the localization accuracy of the multi-point localization algorithm in the subsequent flight experiments.The validity of the deviation correction method based on the trajectory correction was verified,and the correction factor was further modified by the flight data.Verify the optimal flight path.