Design Of 3D Robot Active Olfaction Simulation Platform

The leakage of toxic and harmful gases or odors usually causes serious injury and property loss.When the leakage of odor occurs,it is very important to detect,track and localize hazardous odor sources quickly and accurately.With the development of artificial intelligence and robotics,it becomes possible that autonomous robots take the place of operators to locate dangerous odor sources,and the research field of robot active olfaction,which uses sensors on mobile robot platforms to sniff odors,is gradually emerging.At present,researchers in this field mainly use ground mobile robots to carry out research on robot active olfaction in two-dimensional environments.However,since odor diffusion is a three-dimensional(3D)scientific phenomenon,it is very necessary to measure odor concentration using unmanned aerial vehicles(UAVs),which can move freely in 3D space.Considering that it is difficult to carry out a large number of experiments on 3D active olfaction and the odor plume cannot be repeated in the actual environments,the design of a 3D robot active olfaction simulation platform based on rotor UAVs is studied in this thesis.The main achievements are summarized as follows:(1)A numerical model of the rotor aerodynamic effect and UAVs dynamics on odor diffusion is established.The wind field generated by the rotor rotation is theoretically analyzed using the free vortex method in fluid mechanics.The rotor wake is simplified as a spiral vortex filament structure,and the differential control equation of the vortex filament motion is established.According to the position of the vortex filament,the turbulent wind field generated by a rotor can be accurately calculated.UAVs will move while measuring odor.By establishing the dynamic model and controller model of a UAV,its movement can be accurately simulated,and then the disturbance flow field generated during its movement can be calculated by combining with the rotor vortex filament model.(2)A simulation platform for the study on robot active olfaction in 3D spaces is developed.The advection wind field generated using FLUENT is integrated into the 3D simulation platform as the environment wind field after the data is processed.Programs for the rotor vortex model,unmanned aerial vehicle dynamics model and controller model are compiled,and the disturbance flow field under the influence of UAVs rotor is solved by parallel calculation.The 3D platform can simulate the odor diffusion of a variety of rotor robots,such as single rotor,three rotor,four rotor and six rotor,during the sniffing process.(3)The simulation results of the 3D active olfaction in indoor environments are analyzed,and the model in the simulation platform is verified by experiments.In indoor scenarios,the effect of the simulation platform is analyzed by taking the most used quadrotor as an example.In order to verify the mathematical model used in the simulation platform,the plume diffusion trajectory in the experimental process is extracted by an image processing method.The experimental results and simulation results of three different altitudes of UAV are compared to verify the effectiveness of the simulation results.