# Applied Research of the UAV Illumination Measurement System in Sports Stadiums
## 1 Introduction  
With the development of the economy and society, the number of sports grounds has arisen rapidly and sports venues that can host major events are being built continuously. When an international event will be hosted, illumination requirements usually cover not only sports areas but also audience areas. According to the General Lighting Standards for the Olympic Games, the average vertical illumination of the cameras should be no less than 25% of the playing area, and the illumination should be reduced evenly to less than 10% compared with the illumination of the playing areas in the audience area from row 12 onwards [1]. In general, comprehensive stadiums are divided into six levels according to the Sports Stadium Lighting Design and Inspection Standards (JGI153-2016) [2], and venue lighting levels are generally above level IV because they have to adapt to a variety of competition events [3]. In class IV stadiums, the ratio of horizontal minimum to maximum illuminance should be 0.3 and the ratio of horizontal minimum to average illuminance should be 0.7. Meanwhile, when broadcasting is required, the vertical illumination of the primary and secondary cameras should also be taken into account. The vertical illuminance in the direction of the main camera should be 1000 lx, while the vertical illuminance in the direction of the secondary camera should be 750 lx [4]. With this requirement, the measuring range may be very large. In addition, it can be difficult to measure vertical illuminance. In addition, when the illumination is measured in swimming competition venues, the measurement process may be inconvenient because of venue restrictions. Faced with measurement on a large scale and complex scenarios, traditional measurement methods often take a lot of time and face big challenges. It is an excellent solution to the problems of taking advantage of the convenience of flying with UAVs, with the maturityof UAV technology and the continuous development of UAV application research. Initially, UAVs were invented for military use. In recent years, the acquisition of low-cost sensors and platforms has laid the foundation for the civilian use of UAVs, with the increasing maturity of metal electromechanical systems and microsensor technologies [5]. And a growing number of related aspects of research and commercial applications are emerging due to the convenience of UAVs [6; 7]. Many studies and discussions on UAVs continue to uncover more potential for drone application technology [8; 9]. [PERSON] and [PERSON] et al. [10] applied UAVs to photogrammetry and remote sensing by extracting information from images and generating 3D data; [PERSON] et al. [11] used UAVs to help with 3D modeling, reconstructing the 3D shape of a building or area. [PERSON] et al. [12] conducted a study on how UAVs can be used in disaster detection to map the situation and provide up-to-date information after a catastrophic event or before an anticipated event. There are also some people who have done much research to study how to measure illumination in a quicker and more convenient way using UAVs. [PERSON], et al. [13] use a PHANTOM UAV with an illumination sensor to obtain data. In the paper, the authors measured the horizontal and vertical illumination in the gymnasium. The feasibility of the gymnasium illumination measured by UAV is demonstrated. In addition, they also discussed the illumination of the gymnasium in three dimensions, and the flow of light inside the gymnasium space. In fact, UAVs are already being used in many areas of measurement. Sensor-mounted UAVs also have been used in a variety of measurement applications [14; 15]. However, illuminance, an important light environment parameter, has been relatively little studied in applications using UAV measurements, and most of the applications in UAVs are based on the functionality of the drones themselves, which is less integrated with increasingly sophisticated automation and IoT technologies.