1、 Preparation before operation

1. Environmental and weather inspection

• Wind speed limit：
  • Most aircraft models require a wind speed of ≤ 5m/s (about level 3 wind). Strong winds can cause the liquid medicine to drift, pollute non target areas (such as adjacent farmland and water sources), and even cause drug damage.
  • Use an anemometer for on-site measurement to avoid making judgments based on intuition.
• Temperature and Humidity：
  • Avoid working at high temperatures (>35 ℃) or low temperatures (<10 ℃): High temperatures can accelerate the volatilization of pesticides, while low temperatures may affect their efficacy (such as some biopesticides requiring specific temperatures).
  • When the humidity is less than 40%, the medicine is prone to evaporation, and it is necessary to adjust the spraying amount or choose an anti evaporation agent.
• Rainfall and Light：
  • There is no rainfall forecast within 2 hours before and 4 hours after the homework to prevent the medication from being washed away and ineffective.
  • Avoid direct sunlight (such as noon) and reduce pesticide photolysis. It is recommended to work in the early morning or evening.

2. Venue and obstacle assessment

• Topographic survey：
  • Use map software (such as Google Earth) or field measurements to mark obstacles such as high-voltage lines, trees, and houses.
  • Fields with a slope greater than 15 ° should be operated with caution to prevent the drone from overturning or losing control.
• Water sources and pollution risks：
  • Stay away from sensitive areas such as rivers, lakes, and aquaculture areas to avoid water pollution caused by the infiltration of medicinal liquids.
  • The water used for cleaning equipment after homework needs to be centrally treated and direct discharge is prohibited.

3. Equipment and Pharmaceutical Inspection

• Drone Status：
  • Check whether the propeller, motor, battery, nozzle and other components are intact, and whether the screws are loose.
  • Test whether key functions such as flight control, obstacle avoidance system, and spray flow are functioning properly.
• Pharmaceutical preparation：
  • Dilute the medication strictly according to the instructions to avoid drug damage caused by high concentration or failure caused by low concentration.
  • Use specialized dispensing containers to prevent cross contamination (such as mixing herbicides and insecticides).
  • The remaining medicinal solution should be sealed and stored, labeled with the name and preparation date to avoid misuse.

2、 Key control points during operation

1. Flight parameter settings

• Height and speed：
  • The recommended flight altitude is 2-4 meters. If it is too low, it may collide with crops, and if it is too high, it may cause the medicine to drift.
  • Flight speed adjusted according to crop type:
    • High stem crops such as corn and wheat: 4-6m/s
    • Low stem crops such as rice and vegetables: 2-4m/s
• route planning：
  • Use ground station software to set up "well" or "return" shaped routes, ensuring full coverage without overlap.
  • Reserve a safety margin of 1-2 meters to avoid missed or repeated spraying.

2. Spraying process monitoring

• Real time traffic calibration：
  • Monitor the spray volume through ground stations or mobile apps. If the deviation from the set value is greater than 10%, stop the machine and check the nozzle or pipeline.
  • Regularly clean the nozzle (2-3 acres per operation) to prevent blockages from affecting the atomization effect.
• Obstacle avoidance and emergency operations：
  • Enable obstacle avoidance function and manually take over control when encountering obstacles to avoid automatic detours and missed spraying.
  • When the battery level drops below 20%, return immediately to prevent low battery crashes.

3. Personnel safety protection

• Operator protection：
  • Wear protective clothing, masks, gloves, and goggles to prevent medication from coming into contact with the skin or inhalation.
  • Smoking and eating are prohibited during homework, and exposed areas should be cleaned with soap after homework.
• Spectator management：
  • Set up a cordon to prohibit non operators from entering the work area (with a radius of at least 50 meters).
  • Special reminder to children, pregnant women, and the elderly to stay away and avoid secondary exposure to medication.

3、 Post operation maintenance and compliance

1. Equipment cleaning and maintenance

• Body cleaning：
  • Rinse the drone shell, medicine box, and spray bar with clean water to remove residual chemicals (avoid using high-pressure water guns to directly impact the motor).
  • After cleaning, wipe dry with a dry cloth to prevent metal parts from rusting.
• Component maintenance：
  • Remove the nozzle and soak it in clean water, then use a soft bristled brush to clean the internal impurities.
  • Check the battery level and keep it at 40% -60% during storage to avoid overcharging or overdischarging.

2. Waste disposal

• Empty medicine bottle/bag：
  • Collect and hand over to professional institutions for disposal, and prohibit arbitrary disposal or incineration (which may release toxic gases).
• Remaining medicinal solution：
  • If storage is required, label with name, concentration, and date, store in a cool and dry place, away from food and children.
  • If it needs to be discarded, dilute it according to local environmental requirements and spray it on designated wasteland. Do not pour it into the sewer.

3. Records and Compliance

• work record：
  • Record information such as homework time, location, medication name, dosage, weather conditions, etc., and establish a traceable file.
  • Some regions require submission of work reports to the agricultural department for filing (such as when using restricted pesticides).
• Compliance with regulations：
  • Confirm if the work area is within a no fly zone (such as near airports or military zones).
  • The use of registered pesticide varieties is prohibited beyond the scope (such as using herbicides on vegetables).

4、 Common risks and countermeasures