Drone spraying is a new type of operation method in technological development. High work efficiency, suitable for large-scale agricultural pest control. This is tens or hundreds of times more than physical labor. It can complete tasks that are easy to manually complete, such as forest and mountain forest operations. So how effective are unmanned aerial vehicles used for medicinal purposes on rural land? Things often have two sides, namely advantages and disadvantages. Drone spraying is no exception, each with its own advantages and disadvantages. The advantage is that the spraying speed is fast. The crop protection drones used for agricultural spraying are generally multi rotor aircraft, much larger than typical small aerial photography drones, with longer endurance and much faster speed. Not to mention, compared to manual spraying, the spraying efficiency of aircraft is hundreds of times higher. In addition, crop protection drones can adopt two control methods: manual remote control and satellite guided control. Usually, large plots use satellite navigation to control spraying. For land parcels, seamless spraying can be achieved without losing crops. No matter how slow and careful manual spraying is, there will always be omissions at the beginning, which machines cannot match The spraying quality is also very high. The principle of drone spraying is to install the medicine box on the body of the drone, open the valve after the drone takes off to discharge the medicine, and then use the strong wind generated by the high-speed rotation of the drone blades to atomize and blow down the medicine. Due to the strong atomization and falling of drugs by the wind, the adhesion and diffusion rate of drugs is higher than traditional manual spraying, so the effect of spraying drugs in this way is higher than manual spraying. In fact, there are many potential safety hazards hidden in drones, and some issues have also been documented in previous reports. For example, during the process of spraying pesticides, if no pesticides are sprayed into the river, all organisms in the river will be poisoned. A clear river on the horizon is easily destroyed. If there are artificially cultivated aquatic products in the Tianbian River, it is easy to become an economic dispute if such a problem is encountered. In addition, the promotion of drone pesticide spraying in modern rural areas is insufficient, and there are many regulatory loopholes. Relevant departments need to introduce policies to guide and manage it correctly, avoid irreparable losses caused by technical errors, and ensure the safety of drone pesticide spraying. Therefore, if rural areas want to implement drone pesticide spraying, corresponding technical support must be provided first, and drone training must be provided to farmers to ensure that they use drones in the correct situations, thereby avoiding many problems. As long as they have sufficient technology, they must maintain consistency in the spraying process. In addition, due to its fast speed, the effect of uniform application is poor. The drone spray passes through instantly, making it difficult to mix evenly and thoroughly. The only way to overcome the problem of uneven and thorough beating is to increase the concentration of the liquid medicine, thereby increasing the investment cost. For example, when spraying drugs in cotton fields, UAV spray can not kill cotton bollworm in cotton buds, aphids on the back and bottom of leaves. Only by absorbing crops can endogenous pests be dealt with, and some pests may not be killed by endogenous agents but can only be dealt with through contact. The main disadvantage of manual spraying is slow speed, making it difficult to spray at high altitudes. It has the advantage of uniform application, which can evenly and thoroughly hit crops up and down. Save technical solutions. Although there are many advantages to using drones to spray pesticides, such as high efficiency and good quality, there are also certain limitations. For example, it depends on weather conditions. It cannot take off in bad weather and cannot work all day. It is only suitable for the vast northern regions, while the southern mountainous and hilly areas are not particularly suitable for large-scale operations. Generally speaking, using drones to spray pesticides on farmland is very cost-effective. Short time, uniform spraying, and affordable price. Therefore, more and more farmers are gradually choosing to use drones to spray pesticides on crops. There are also many smart young people who see the vast prospects of this industry, specializing in drone spraying, and the profits are still considerable. Drones are a manifestation of high-tech technology applied in agriculture, and are a progressive product of the combination of modern technology and traditional agriculture. From an efficiency perspective, it is indeed higher than manual spraying. From a practical perspective, it cannot be compared to manual operation. Drones can only spray on the front of crops, but cannot spray on the back of crops. When spraying pesticides, unmanned aerial vehicles also pay attention to the weather. Due to strong winds and heavy fog, it is impossible to operate, and manual operation can completely ignore this situation. Therefore, unmanned operation has its own advantages, and manual operation also has its advantages, which should be complementary. We cannot veto drones with one vote. We should view new things from a developmental perspective. Although there are drawbacks to drone operation, it is an assistant for the future development of agriculture.

With the rapid development of technology, drones, as a new type of intelligent aircraft, have been widely used in various fields such as aerial photography, agriculture, logistics, and rescue. So, how do drones achieve precise control? This article will provide a detailed answer to this question regarding the control principles, control systems, control methods, and future development trends of unmanned aerial vehicles. 1. Control principle of unmanned aerial vehicles The control principle of unmanned aerial vehicles is mainly based on aviation mechanics, electronic technology, and control theory. Its core lies in real-time monitoring and adjustment of the attitude, speed, altitude and other parameters of the drone through its internal flight control system, in order to achieve stable flight and precise control. The drone flight control system usually consists of three parts: sensors, controllers, and actuators. Sensors are responsible for collecting information such as the attitude, speed, and altitude of drones. The controller calculates control instructions based on this information and then drives the drone to perform corresponding actions through actuators such as motors and servos. 2. Control system of unmanned aerial vehicle The control system of unmanned aerial vehicles is the key to achieving precise control. Generally speaking, the control system of a drone includes two parts: ground control system and onboard control system. The ground control system mainly consists of remote controllers, ground stations, and other equipment. The remote control communicates with the drone through wireless signals, and the operator can issue control commands through the remote control to control the drone's takeoff, landing, flight trajectory, etc. The ground station is responsible for higher-level task planning, data processing, and real-time monitoring functions. The onboard control system mainly includes flight control board, sensors, actuators, etc. The flight control board is the "brain" of the drone, responsible for processing information from sensors and calculating control commands. Sensors are responsible for collecting various status information of drones, such as attitude, speed, altitude, etc. The executing mechanism drives the various components of the drone to perform corresponding actions according to the instructions of the flight control board. 3. Control method of unmanned aerial vehicle There are various control methods for drones, including manual control, automatic control, and hybrid control. Manual control is the most direct control method, where operators issue commands through a remote control to control the flight of the drone. This method requires operators to have certain flying skills and experience, but can achieve high flexibility and real-time performance. Automatic control is the use of pre-set programs or algorithms to enable drones to autonomously complete flight tasks. This method does not require manual intervention and can greatly improve the stability and efficiency of flight. For example, in the field of aerial photography, drones can automatically capture images through pre-set routes, greatly reducing the burden on operators. Hybrid control is a combination of manual control and automatic control, which retains the flexibility of manual control while leveraging the stability advantage of automatic control. In practical applications, operators can flexibly choose control methods based on task requirements and environmental changes. 4. The development trend of drone control technology With the continuous development of technologies such as artificial intelligence and big data, drone control technology is also constantly advancing. In the future, drone control technology will present the following development trends: Intelligence: By introducing artificial intelligence algorithms, unmanned aerial vehicles can achieve autonomous decision-making and intelligent obstacle avoidance functions, improving flight safety and efficiency. Clustering: Through drone clustering technology, multiple drones can collaborate to improve task execution efficiency and reduce costs. Cloudization: With the help of cloud computing and big data technology, real-time transmission and processing of drone data can be achieved, providing strong support for decision-making. Standardization: With the continuous expansion of the drone market, the standardization and normalization of drone control technology will become an inevitable trend, which will help promote the healthy development of the drone industry. In summary, the control of Agricultural drones involves multiple fields such as aviation mechanics, electronic technology, and control theory, achieving precise control through flight control systems, control systems, and various control methods. With the advancement of technology, drone control technology will continue to develop towards intelligence, clustering, cloud computing, and standardization, providing more efficient, secure, and convenient support for applications in various fields. In the future, drones will play an important role in more fields, bringing more convenience and possibilities to human production and life.