How does a plant protection drone spray pesticides?

The plant protection UAV spraying system mainly includes medicine box, water pump, hose and sprinkler. The prepared pesticide is loaded into the medicine box, the water pump provides power drainage, and then reaches the nozzle through the catheter, spraying the pesticide evenly to the surface of the crop.

Medicine chest

The key to the design of the medicine box is to prevent the concussion of the medicine liquid, because the stable flying state of the UAV is the key to uniform spraying during the spraying process of the plant protection UAV.

Water pump

The pumps used by plant protection drones are usually divided into peristaltic pumps, gear pumps and high pressure pumps.

Peristaltic pump by squeezing the hose to drive the water in the tube, the hose is generally used silicone tube, it is subject to the rotor pressure and wear larger, so the material requirements are very high, peristaltic pump silicone tube must have corrosion resistance, aging resistance, high resilience and other properties.

Gear pumps are also called positive displacement devices like a piston inside a cylinder. When one tooth enters the fluid space of another tooth, because the liquid is incompressible, the liquid and the tooth cannot occupy the same space at the same time. In this way, the liquid is mechanically displaced. Due to the continuous tooth clamping, this phenomenon continues to occur, and thus provides a continuous exclusion at the outlet of the pump, and the amount of discharge is the same with each turn of the pump.

sprayer

At present, the spraying system of plant protection UAV mainly uses two kinds: fan pressure nozzle and centrifugal nozzle.

The principle of the pressure nozzle is that the pressure generated by the liquid pump breaks the liquid into small droplets under the action of pressure when the liquid passes through the nozzle, and the fog particle size is mainly affected by the pressure and the aperture of the nozzle.

Advantages: The pressure under the liquid medicine is large, the penetration is strong, the amount of liquid medicine produced is small, and it is not easy to evaporate and lose due to high temperature and drought. And the spraying system is relatively simple and low cost.

Disadvantages: The liquid atomization is not uniform, the diameter of the droplet is relatively different, and the nozzle is easy to block, especially when spraying powder.

The principle of the centrifugal nozzle is that the nozzle is driven by the motor to rotate at high speed, and the pharmaceutical liquid is broken into small droplets through centrifugal force, and the fog size is mainly affected by the motor voltage.

Advantages: liquid medicine atomization uniform, atomization effect is good, droplet diameter difference is not large.

Disadvantages: the centrifugal nozzle basically has no downpressure, completely relying on the wind field pressure of the drone, compared with the pressure nozzle, the amount of drift is larger, and the effect is poor for high-pole crops and fruit trees. And the accessories of the centrifugal nozzle are easy to have problems, the motor of the brush motor version is easy to damage, the life is short, the replacement frequency is higher, and the cost of the brushless motor version is higher.

In general, it is better to choose pressure sprinkler for single rotor plant protection UAV, such as fruit trees, high stalk corn and other crops spraying and controlling rice planthopper, the control effect of single rotor plant protection UAV of Tianying Brothers will be better.

On the other hand, when high-density crop spraying operations, the pressure nozzle will be more suitable, such as cotton spraying defoliant, the penetration of the pressure nozzle is relatively strong, the effect will be better.