Research On 3D Spatial Positioning Of Micro-UAV

Unmanned Aerial Vehicles(UAV)have been widely used in military,civil and scientific research because of their low cost,low loss,and no casualties.Therefore,UAV is one of the fastest-growing high technology.Compared with the military UAVs,the micro-UAVs have the advantages of smaller size,lower cost and higher flexibility,which are more applicated in the civil and scientific fields.On the other hand,micro-UAVs are also easily affected by air currents and other factors in the environment due to their small masses and low inertia,which may cause deviations from the default route.Therefore,precise and real-time positioning of the micro-UAVs are in urgent need.Unfortunately,although the research on the location of military UAVs is relatively mature at present,their commonly used methods such as Doppler geodesy and radar are not suitable for micro-UAV systems,due to their complex structure,large size,heavy weight,high price and other factors.The thesis combines the Wireless Sensor Network(WSN)node localization algorithm and the Strap-down Inertial Navigation System(SINS)to accurately locate the real-time three-dimensional(3D)position of a micro-UAV.Taking the advantages of the low cost and good expansibility of WSN,it revises the localization results of the SINS embedded in the micro-UAV.A localization method for the UAV system is proposed which could achieve accurate positioning and real-time performance.Firstly,the SINS inertial device(gyroscope and accelerometer)and solution process is studied.It is found that the positioning of SINS on the micro-UAV has errors increasing exponentially with time.In order to achieve the precise positioning of the micro-UAV,combined with the WSN node location algorithm,the micro-UAV is positioned as the target node to correct the SINS positioning result.Then,considering the economy and positioning accuracy,combined with WSN energy management,the Ultra-Wideband(UWB)node is selected to transmit information between WSN nodes.Based on the Multi-pulse Asynchronous Transmission Localization(MATL)algorithm,a Dynamic Clustering MATL(DCMATL)algorithm is proposed.The algorithm selects the nearby anchor nodes according to the basic position information obtained by SINS,and then locates the micro-UAV in the 3D space based on the WSN measurement information.Finally,the MATLAB simulation experiment is carried out,and the positioning error,calculation time and energy consumption are compared with other classical positioning algorithms.The simulation results showed that the proposed DCMATL can effectively solve the problem that the positioning error of the micro-UAV using the SINS increases exponentially with time,and maintain the positioning error of the micro-UAV within 0.1 m to achieve accurate positioning of the micro-UAV.Besides,the DCMATL algorithm computing time is between 0.06 and 0.2s,and the average time is less than 0.08s,which is far lower than the classical MATL algorithm,ensuring the real-time positioning of the micro-UAV.