The Light And Small POS Key Technology And Its Application In Remote Sensing Of UAV

The UAV remote sensing measurement system consists of three parts: flight platform,Position and Orientation System(POS)and remote sensing load.The aerial survey system with light and small drones as the flight platform has the advantages of low cost,strong adaptability,high image resolution,flexibility,low environmental requirements,portability and transportation,and can be widely used in 3D urban modeling,regional planning,precision agriculture,power inspection,environmental monitoring and other aspects.The positioning and attitude measurement system integrates the differential GNSS high-precision positioning system with the Inertial Navigation System(INS)to provide position and attitude reference for aerial remote sensing based on direct georeferencing,and is to obtain high-quality remote sensing imaging.key.In order to adapt to the small payload,low endurance and low cost of light and small drones,a micro-electro-mechanical system(MEMS)inertial sensor with high performance,light weight,small size and low cost is usually used in light and small POS systems.The acquisition of high-precision POS data through low-precision,low-cost GNSS/MEMS INS combination for remote sensing measurement of UAVs is of great significance for the development of geographic mapping.This thesis studies and analyzes the key technologies of light and small POS and its application in remote sensing of UAVs,specific as follows:1.This thesis summarizes the basic principles of POS supported UAV remote sensing system,and discusses the principle of POS assisted aerial photogrammetry and laser radar scanning measurement.From the basic theory,the mutual coordinate matrix of the relevant coordinate system involved in the POS-assisted aerial remote sensing system is analyzed,as well as the technical process and attention points of remote sensing operation.2.This thesis summarizes the basic principles and combination methods of DGNSS positioning and INS positioning.Based on the high order Kalman smooth filter algorithm,loosely couple integrated system uses the GNSS carrier phase observation double difference difference calculation to obtain the position and velocity of the flight platform and the observation data collected by the IMU for calculation.Then the thesis uses the three-way smoothing filter to improve the algorithm and further improve the accuracy of position and attitude.3.This thesis analysis the error source of UAV remote sensing system and its influence on the accuracy of mapping.Then it analyses the influence of the initial parameters of Kalman filter on the accuracy of POS positioning and its influence on the mapping error.The accuracy analysis of the imagery remote sensing and airborne radar mapping results is carried out to verify the effectiveness and feasibility of the POS system.