Effects of operation height and tree shape on droplet deposition in citrus trees using an unmanned aerial vehicle

2018 ◽  
Vol 148 ◽  
pp. 1-7 ◽  
Author(s):  
Y. Tang ◽  
C.J. Hou ◽  
S.M. Luo ◽  
J.T. Lin ◽  
Z. Yang ◽  
...  
2019 ◽  
Vol 35 (3) ◽  
pp. 367-376 ◽  
Author(s):  
Qiang Shi ◽  
Hanping Mao ◽  
Xianping Guan

Abstract. To analyze the droplet deposition under the influence of the flow field of an unmanned aerial vehicle (UAV), a hand-held three-dimensional (3D) laser scanner was used to scan 3D images of the UAV. Fluent software was used to simulate the motion characteristics of droplets and flow fields under the conditions of a flight speed of 3 m/s and an altitude of 1.5 m. The results indicated that the ground deposition concentration in the nonrotor flow field was high, the spray field width was 2.6 m, and the droplet deposition concentration was 50 to 200 ug/cm2. Under the influence of the rotor flow field, the widest deposition range of droplets reached 12.8 m. Notably, the droplet deposition uniformity worsened, and the concentration range of the droplet deposition was 0 to 500 ug/cm2. With the downward development of the downwash flow field, the overall velocity of the flow field gradually decreased, and the influence interval of the flow field gradually expanded. In this article, the droplet concentration was verified under simulated working conditions by a field experiment, thereby demonstrating the reliability of the numerical simulation results. This research could provide a basis for determining optimal UAV operating parameters, reducing the drift of droplets and increasing the utilization rate of pesticides. Keywords: Unmanned aerial vehicle (UAV), Aerial application, Downwash flow field, Droplet deposition, Simulation analysis.


Agronomy ◽  
2020 ◽  
Vol 10 (2) ◽  
pp. 215 ◽  
Author(s):  
Qinggang Xiao ◽  
Rui Du ◽  
Lin Yang ◽  
Xiaoqiang Han ◽  
Sifeng Zhao ◽  
...  

Processing pepper planting and processing have become an important red pillar industry in Xinjiang. With the continuous growth of processing pepper planting areas in Xinjiang, diseases and pests are increasing year by year. The aim of this study was to compare the droplet deposition and control efficiency of unmanned aerial vehicle (UAV) and electric air-pressure knapsack (EAP) sprayers on a processing pepper field. The UAV sprayer had a poor droplet coverage rate, droplet density, and deposition uniformity, but displayed the best deposition (1.01 μg/cm2, which was 98% more than the EAP sprayer). The control efficacy of the UAV sprayer on processing pepper fields with Phytophthora capsici and aphids was slightly lower than that of the EAP sprayer. When the UAV sprayer was used to control processing pepper diseases and pests, it could reduce the pesticide dosage on the premise of ensuring the control effect. Further study of the residue of high concentration pesticides in pepper fruit and environment sprayed by UAVs are needed.


Agronomy ◽  
2019 ◽  
Vol 9 (5) ◽  
pp. 217 ◽  
Author(s):  
Qinggang Xiao ◽  
Fang Xin ◽  
Zhaoxia Lou ◽  
Tingting Zhou ◽  
Guobin Wang ◽  
...  

Defoliant spraying is an important aspect of mechanized cotton harvesting. Fully and uniformly spraying defoliant could improve the quality of defoliation and reduce the impurity content in cotton. Improving the coverage of defoliant droplets in the middle and lower layers of cotton and ensuring the full and even dispersion of droplets in the cotton canopy are essentially in increasing the defoliation effect. In this study, we assessed the effect of aviation spray adjuvants on droplet deposition, defoliation, boll opening and defoliant retention in cotton leaves sprayed by an unmanned aerial vehicle (UAV). The results showed that adding aviation spray adjuvants could significantly improve the defoliant droplet deposition. Fifteen days after spraying, the defoliation rate was 80.31% and the boll opening was 90.61%. The defoliation rate increased by 3.12–34.62% and the boll opening rate increased by 6.67–29.56% after the addition of aviation spray adjuvants. Using a vegetable oil adjuvant could significantly increase the droplet coverage rate and the retention of defoliants in cotton leaves.


Agronomy ◽  
2020 ◽  
Vol 10 (2) ◽  
pp. 303
Author(s):  
Pengchao Chen ◽  
Yubin Lan ◽  
Xiaoyu Huang ◽  
Haixia Qi ◽  
Guobin Wang ◽  
...  

Previous studies have confirmed that choosing nozzles that produce coarser droplets could reduce the risk of pesticide spray drift, but this conclusion is based on a large volume of application, and it is easy to ignore how this impacts the control effect. The difference from the conventional spray is that the carrier volume of Unmanned Aerial Vehicle (UAV) is very limited. Little was known about how to choose suitable nozzles with UAV’s limited volume to ensure appropriate pest control. Droplet deposition with the addition of adjuvant and the LU110-010, LU110-015, and LU110-020 nozzles and control of planthoppers within nozzles treatments were studied by a quadrotor UAV in rice (Tillering and Flowering stages). Allura Red (10 g/L) was used as a tracer and Kromekote cards were used to collect droplet deposits. The results indicate that the density of the droplets covered by the LU110-01 nozzle is well above other treatments, while the differences in droplet deposition and coverage are not significant. The deposition and coverage were improved with the addition of adjuvant, especially in LU110-01 nozzles’ treatment. The control effects of rice planthoppers treated by LU110-01 nozzle were 89.4% and 90.8% respectively, which were much higher than 67.6% and 58.5% of LU110-020 nozzle at 7 days in the Tillering and Flowering stage. The results suggest that selecting a nozzle with a small atomizing particle size for UAV could improve the control effect of planthoppers.


2016 ◽  
Vol 85 ◽  
pp. 79-88 ◽  
Author(s):  
Wei-Cai Qin ◽  
Bai-Jing Qiu ◽  
Xin-Yu Xue ◽  
Chen Chen ◽  
Zhu-Feng Xu ◽  
...  

2020 ◽  
Vol 20 (4) ◽  
pp. 332-342
Author(s):  
Hyung Jun Park ◽  
Seong Hee Cho ◽  
Kyung-Hwan Jang ◽  
Jin-Woon Seol ◽  
Byung-Gi Kwon ◽  
...  

2018 ◽  
pp. 7-13
Author(s):  
Anton M. Mishchenko ◽  
Sergei S. Rachkovsky ◽  
Vladimir A. Smolin ◽  
Igor V . Yakimenko

Results of experimental studying radiation spatial structure of atmosphere background nonuniformities and of an unmanned aerial vehicle being the detection object are presented. The question on a possibility of its detection using optoelectronic systems against the background of a cloudy field in the near IR wavelength range is also considered.


Author(s):  
Amir Birjandi ◽  
◽  
Valentin Guerry ◽  
Eric Bibeau ◽  
Hamidreza Bolandhemmat ◽  
...  

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