Study On Construction And Fusion Of Gas Concentration Maps Based On Olfactory UAVs

The air pollution problem caused by the current imbalanced and inadequate development has become one of the people's livelihood problems urgently to be solved in contemporary society.More and more scholars are also studying the leakage and distribution of the gas that causes environmental pollution.The gas concentration map construction and fusion studied in this thesis refers to the use of quadrotor unmanned aerial vehicle(UAV)to construct the gas concentration map of the target area.and then the image processing method is used to fuse(splice and repair)each sub-map to obtain a complete gas concentration map of a plane in the target monitoring area.It can be applied to various occasions such as gas leakage sites and urban traffic congestion areas,and provides a reference method for monitoring air quality and environmental pollution,which has important research significance and application value.The main work of this thesis is as follows:1)An olfactory UAV platform under outdoor environment is built,and the zero point calibration of the carbon dioxide sensor is performed,then the temperature compensation algorithm of cubic spline interpolation is used to compensate the temperature for the selected non-dispersive infrared absorption gas sensor.The olfactory sensor system built can avoid the influence of UAV rotor airflow on sensor data sampling.2)The spatio-temporal analysis algorithm is used to unify the gas concentration information sampled by each UAV sensor to the same moment,and the Kernel DM algorithm is used to construct a gas concentration sub-map.Aiming at the interval and overlap between sub-maps,the image repair algorithm based on CDD(Clustered Directed Diffusion)model and the image mosaic algorithm of trigonometric function weights are used to fuse the gas concentration sub-maps,and these are verified by simulation experiments.3)An experimental scene is built outdoors.First,the air generated by dry ice is used to simply simulate the polluted area,and a rotor airflow analysis experiment is designed to verify the feasibility of the built olfactory UAV platform;Then,by controlling two four-rotor UAVs to sample gas concentration according to a predetermined path,the gas concentration sub-maps are constructed according to the collected gas information,and then the sub-maps are fused to obtain a complete gas concentration map of the monitoring area;Finally,combined with the complete gas concentration map,the approximate location of the leakage source area and the possible change trend of the gas are analyzed.