3D Visualization Simulation For Flight Conflict Scenes In Low-altitude Airspace

With the development of national economy in our country, people’s demand for general aviation was increasing in recent years. Flight activities in the low-altitude airspace, as an important part of the general aviation, became more and more attention by all of us. The number and type of aircraft in the low-altitude airspace will increase inevitably in the future. And the kind of people relate to the low-altitude airspace will be diversified. With the large-scale use of unmanned aerial vehicle in the commercial and civil in the past two years, the security of flight activities in the low-altitude airspace became prominent increasingly. In the process of low-altitude airspace opening, we need to learn from foreign experience of developed countries, using 3D visualization technology to supervise the flight activities in low-altitude airspace, to ensure the safety and efficiency of flight activities.Flight conflict with different types of objects may take place while the aircraft flying in the low-altitude airspace. In order to avoid these flight conflict, this paper establishes the 3D visualization model of the flight conflict and carries on different early warning methods for the conflict, so as to ensure the flight safety of aircraft.The aircraft in the low altitude will meet two types of flight conflict, one kind of them is the conflict between aircrafts and the ground obstacles including the towering buildings, undulating terrain and the no-fly zone; One kind of them is the conflict between aircrafts. According to the analysis of two types flight conflict which may appear in the process of flight activities in the low-altitude airspace,this thesis establishes two types of 3D visualization model of flight conflict. In order to solve the flight conflict, this thesis designs a linear program method of conflict resolution algorithm.Firstly, this thesis analyzes the characteristics of aircraft in the low-altitude airspace and consults the aircraft’s space protection model of high altitude fixed route flight then establishes two layers of space protection model of the aircraft, which is the early warning area sphere and alert area sphere. This makes the flight of the aircraft in the low-altitude airspace safer and more flexible, which could improve the utilization coefficient of the low-altitude airspace.Then, according to the three types of low-altitude airspace which is divided by provisions on the administration of the use of low altitude airspace, this thesis selects three corresponding typical flight scenes, airports cities and mountains to analyze. Considering to the flight safety and the efficiency of algorithm, the author establishes the mathematical model of three typical flight scenes. Airport model is a three-dimensional space, usually manifests as an ellipse, a sector and an arbitrary polygon; City model manifests as a relatively balanced BSP scenes tree and the cylindrical bounding volume of obstacles; While mountain model manifests as some pieces of Mosaic whose length and width are equal, height of grid is the highest value of the terrain. This thesis carries on 3D visualization of the three typical flying scenes and the possible flight conflict with different early warning methods in the software of Vega Prime.Furthermore, from the analysis of the two aircrafts’ flight conflict in the low-altitude airspace, the author studies on three and four aircrafts’ flight conflict model further, then promotes to N aircrafts’ flight conflict finally. From the analysis of the two aircrafts’ flight conflict in the low-altitude airspace, the author studies on three and four aircrafts’ flight conflict model further, then promotes to N aircrafts’ flight conflict finally. After that, this thesis establishes and carries on 3D visualization of the flight conflict detection model of multi- aircraft in the typical low-altitude airspace. Lastly, Base on the flight conflict detection between the aircraft model, the author has carried on the preliminary exploration of conflict resolution model and establishes it’s a linear program method of conflict resolution algorithm which changes the velocity or course angle of the aircraft.