Unmanned aerial vehicle UAV technology for precision agriculture
UAV has entered the precision agriculture market for a short period of time and is in the process of development, and the relevant regulations have not yet been finalized. Although the United States Federal Aviation Administration (FAA) approves the use of UAVs by individuals, it is currently banned for commercial use.
In the case of UAV technology, a qualified aircraft requires basic motor and flight control, sensors, telemetry, and valve actuators and level detection systems for spraying pesticides. It is also recommended to install a radar-based anti-collision device.
Lightweight, low-power, hyperspectral sensors collect data that provides farmers with more crop status information than traditional visible-spectrum cameras. Hyperspectral sensors originated from hyperspectral techniques that were first validated in satellite applications. Data is acquired at a wavelength outside the visible spectrum using a series of detectors, each of which is tuned to ultra near infrared (VNIR, 380 to 1000 nm), near infrared (NIR, 900 to 1700 nm) or short wavelength infrared (SWIR, 950). Working in a narrow band such as 2500 nm). Chemical characteristics or other pests of crop diseases are more clearly observed at this wavelength than the visible spectrum alone. The high-spectrum sensors that are available now are affordable, feature low distortion, wide field of view and onboard processing to eliminate noise and ensure accurate picture capture.
Achieve flight
UAVs for precision agriculture range from small fixed-wing aircraft to multi-rotor four-axis UAV platforms. The UAV used to spray the pesticide may contain six or more rotors to provide sufficient lift, depending on the expected payload.
UAV UAVs typically use a brushed or brushless DC (BLDC) motor to drive the lift rotor. Small aircraft use brushed motors for lightweight and simple features, while UAVs that require high reliability and low electromagnetic noise are more likely to use BLDC, especially large UAVs.
The core component of the aircraft is the flight controller, which handles navigation, controls the motor to complete takeoff, and maintains altitude and heading during flight. GPS navigation combined with lightweight small MEMS sensors such as 3-axis accelerometers, 3-axis gyroscopes and air pressure sensors for accurate positioning, motion control and height perception. In terms of ensuring flight stability, the model helicopter controller prevents the fuselage from rotating along its own axis by controlling the anti-torque tail rotor, which has a similar principle to today's multi-rotor UAV flight controllers. In the UAV controller, the inertial measurement function based on MEMS sensor fusion can adjust the speed of each motor to ensure that the aircraft is flying in the specified direction.
As a precision agriculture aid, the true role of the flight controller is reflected in the user interface and features that can help determine the UAV flight path. Farmers need to accurately determine the UAV flight path in advance in order to obtain a complete picture of a particular area, or to ensure that the drug is fully sprayed in the most cost-effective manner and avoid overspray as much as possible.
