Agricultural Drones

Nowadays, people cannot avoid hearing about drones and the broad scale of their utilization. One of the industries where drone usage is becoming more common is agriculture. Or, to be specific, precision agriculture.

Precision agriculture

The growing demand for food among limited resources cannot be served only by standard equipment and without deploying innovative solutions. This is where precision farming comes into play. It is a general concept for optimizing resources using modern technology and drones. With the use thereof, a farmer can precisely identify where and to what extent a targeted measure is required. 

These aerial vehicles can support precision farming in two ways: aerial mapping and GPS data-based aerial spraying.

Aerial mapping

As seen in recent global market research, mapping is one of the leading drone application methods. Aerial mapping with a proper software background provides data that helps farmers optimize their operations and decrease agriculture’s carbon footprint.

Many unmanned aerial vehicles are so-called rotor-wing aircraft (like small helicopters) that make them capable of VTOL (Vertical Take-Off and Landing) and – more importantly – maintaining a position (certain height and location) in the air without moving (some advanced models can resist wind too). These aspects make them a perfect flying camera that can mount special equipment. This payload can be controlled remotely by the remote pilot (i.e., drone pilot) or another person responsible for the camera, also known as “sensor only.” 

The drones can reach higher altitudes to see the whole area from one angle and take photos of the land the farmer wants to learn about. It takes 15 minutes to map 100 acres with a drone, costing three or four times less than the same activity with manned aircraft. But in the case of aerial mapping, the photos contain much more than a colored picture of the farm. 

Drone sensors use different techniques for visualizing: some sensors shoot in visible light (VIS), and others operate in the nearly infrared spectrum (NIS). The former is cheaper and provides data faster, but the NIS sensors can show if plants suffer from stress caused by lack of water – the plants reflect the different amounts of green and near-infrared lights according to their health. Therefore, the sensors can show that the leaves are healthy, stressed, or dead.

The so-called LIDAR is one of the best technology in aerial mapping. It uses a laser to illuminate the targeted crops and build a 3D model following the analysis of the reflected light.

While the drone and its sensor play the role of the hardware that grants the data input for targeted measures, which is the essence of precision agriculture, there must be a proper means to evaluate this data input: software. This software usually makes proposals for the farmer, suggesting where to intervene and take measures to save the crops without wasting valuable resources like water.

Spraying with drones

Drones can also be utilized in the vital farming area of spraying, a function closely related to using drones for aerial mapping. According to a report from the European Union on the use of drones in agriculture, the highest level of efficiency can be attained by integrating two parts of the process and commencing spraying with drones based on the data collected by a mapping drone. Furthermore, investing in drones for agricultural purposes is also cost-efficient because they can be utilized every season for different purposes.

Agriculture accounts for 70% of global water usage, not only in irrigation but also in spraying. Before the appearance of drones, aerial spraying was conducted exclusively with manned aircraft. These aircraft sometimes carry only 4 liters of pesticides diluted with hundreds of liters of water. Meanwhile, a drone weighing only 25 kg can lift a tank loaded with only 10 liters of the mix of pesticide and water. Using more efficient spreaders in spraying drones results in minimal liquid wastage during spraying operations and significantly reduces water usage.

Modern agricultural drones can spray the carried pesticides at a low speed not maintainable by a manned aircraft. This low speed makes it possible to conduct spraying with advanced accuracy, thereby saving water and pesticides. Also, spraying drones – unlike tractors – cause no crop damage, saving farmers money.

A significant feature of these drones is that their rotors are responsible for lifting the drone and distributing pesticides from the tank. This solution allows for a wider pesticide coverage area than the drone itself, increasing the efficiency of the spraying process. For instance, a DJI Agras T30 drone, which is 2.9 meters wide, can cover an area almost 9 meters wide with this method. 

The load capacity of spraying drones ranges mainly between 10 and 30 liters, meaning that they can spray up to 16 acres an hour. 

Another important feature of spraying drones is that they can fly fully automatically (which is not identical to autonomous flying because the latter concept provides no possibility for the pilot to interrupt or modify the drone’s movement). Therefore, pre-planning the spraying of drones can be instrumental in achieving this optimization.

The future of precision farming

According to a European study, the usage of drones in agriculture will eventually include more than aerial mapping and spraying. For example, there are ongoing experiments and tests for aerial planting where the drone uses compressed air to fire the seed pods straight into the ground. That could further save costs for farmers because this part of agriculture requires a large labor force.

The development of precision agriculture seems to be unstoppable. However, it requires cooperation not only on the manufacturers’ side – pesticide producers should also elaborate processes and obtain a license from agricultural and food surveillance authorities to use their products for spraying with manned and unmanned aircraft.

The following article will introduce the legal aspects of using agricultural drones: 

Africa’s Drone Regulations: How Simple Is It to Operate in The African Market?