# A UAV Wind Field Perception System Inspired by Biological Perception
## 1 Introduction  
Unmanned aerial vehicles have been created for more than a century, and as time goes on, they are growing smarter and performing more consistently. At the moment, the onboard energy system of unmanned aerial vehicles restricts their endurance. Unmanned aerial vehicles' onboard energy weight and endurance are constrained due to the load weight they carry, such as photoelectric detecting equipment, as well as structural strength and flying performance requirements [1, 2]. The remarkable ability of albatroses to harvest energy from the wind field was focused on by the researchers. For the first time, [PERSON] [2] made the observation that birds can obtain energy from the environmental wind field, which focused on the influence of the characteristics of the wind field environment on capacitive gliding [3]. The albatross, a seabird, can take advantage of the horizontal gradient of wind near sea level for long-duration glides. [PERSON] et al. [4] used radar and optical measuring instruments to observe the flight of albatross and other seabirds. The observation results showed in Figure 1A that the flight trajectory of albatross is closely related to the wind field. The two nostrils of albatross have sensitive sensory nerves, as shown in Figure 1B, which are sensitive to information, such as air pressure and smell. Through careful study of GPSdata, [PERSON] and [PERSON] et al. discovered a linear connection between changes in ground speed and wind speed during albatross flight [5; 6; 7]. Researchers believe that this is similar to the function of the pitot tubes used on aircraft, and can be used to monitor the total number of albatrosses during their flight. At the same time, it uses the difference in the flow of the two nostrils to sense the wind direction [8]. [PERSON] et al. [9] examined the energy changes and trajectory strategies during the flight of albatrosses, performed in-depth study of the energy-harvesting mechanism and trajectory of dynamic gliding, and solved the minimal wind gradient necessary under dynamic gliding trajectory circumstances [9; 10; 11]. It is clear that the real-time perception of the wind field is the basis for employing the wind field to achieve energy harvest gliding, whether it is a bird or a UAV. UAVs are known for their inexpensive price, compact size, high mobility, and flexibility. As a result, scientists started using drones to assess meteorological factors, including wind field habitats. UAVs have the characteristics of low cost, small size, and strong mobility and flexibility. Therefore, researchers began to use drones to measure meteorological conditions, such as wind field environments. In 2001, [PERSON] et al. [12; 13; 14] used fixed-wing unmanned aerial vehicles to measure wind speed, temperature, humidity and other meteorological parameters at a height of 2000 m in Kali Gandaki Valley in the Himalayas several times, supplementing the local meteorological data. The measuring range is constrained, and a skilled pilot must maintain steady control of the drone. In 2008, [PERSON] et al. [15; 16] used a small meteorological UAV called M2 AV to conduct wind field measurements. Temperature, humidity, and porous probes were all installed in the aircraft. The airspeed meter is comparable with the measurements made by the radar and the measuring tower. It can measure the wind speed and direction along the route, average wind and turbulence with a resolution of 40 Hz, and high spatial resolution of 55 cm. In 2017, [PERSON] et al. [17] installed an ultrasonic anemometer on a six-rotor UAV to measure the wind profile at 1000 m above the ground. The Aerosonde [18; 19] high-performance long-range UAV was created by [PERSON] et al. and carried a number of sensors to assess the meteorological environment. The Aerosonde UAV obtained the measurement of the wind field by establishing the 'S' flight path, right angle turning, circling around the point, and other flight modes, which employed the horizontal ground speed detected by GPS and the pitot tube to estimate the horizontal wind.