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The use of unmanned aerial vehicles for pesticide spraying is becoming increasingly common to carry out this task mainly because of their speed and effectiveness.The efficient spraying of pesticides for improving the crops yield, and for reducing operations costs and environmental risks is a challenge for precision agriculture.Weather conditions, such as the intensity and direction of the wind while spraying, add further complexity of the problem of maintaining control.It is essential to know the real-time environmental conditions, such as wind,temperature and humidity to minimize contamination.Furthermore, it is useful to collect samples and analyze the quality of crop spraying by evaluating the deposition of the pesticide over the crop.This study proposes the use of wireless sensor networks in a support and control system for crop spraying to gather environment information mentioned above.The information collected by the WSN allows the UAV to confine its spraying of chemicals to strictly designate areas.To gathering real-time information, it needs direct communication between the UAV and sensor nodes.There are some challenging issues remain of the heavy affected problem with the speed of UAVs and network density, also the high conflicts that lots of sensor nodes concurrently send data onto the UAV.To solve those problems, we propose a cluster-divided WSN data gathering algorithm,leveraging both the UAV and relay nodes (RNs) to autonomously collect and process data in wireless sensor networks.Specifically, the UAV dispatches RNs to the network and every RN is responsible for collecting and processing the data from sensor nodes in an area of the network of travelling around that area.The UAV gets desired information via RNs with aggregated sensory data.To realize pesticide precision spraying, We propose and evaluate a method to adjust the UAV route to changes in wind intensity and direction.The way to adapt the path runs in the UAV through the software development kit(SDK) developed by manufactures and its input is the parameters obtained from the wireless sensor network (WSN) deployed in the crop field.The information retrieved by means of the WSN provides the UAV with knowledge of the position and intensity from three different directions detected by draft transmitters from every sensor of the crop field.In the whole process of aerial spraying, the WSN will monitor the wind conditions and make changes in the aerial vehicle path.When a variation in the direction or speed of the wind occurs during spraying, the wireless sensor network detects the change and interacts with the airplane navigation system, by suggesting an alteration in the path, to allow uniform spraying over the target area and avoid spraying outside that area.Through computer simulations, it shows that use the feedback information on the wireless sensor network to make adjustments to the UAVs routes is useful in crop spraying operation to minimize and to control pesticide drift, to improve the quality of application, to reduce environmental contamination and to save time and money.