Location: Crop Production Systems Research Unit
Title: Spatial distribution visualization of PWM continuous variable-rate spray Authors
|Deng, Wei -|
|Zhao, Chunjiang -|
|Wang, Xiu -|
|Liu, Jinglong -|
Submitted to: International Journal of Agricultural and Biological Engineering
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: May 26, 2014
Publication Date: December 20, 2013
Citation: Deng, W., Zhao, C., Huang, Y., Wang, X., Liu, J. 2013. Spatial distribution visualization of PWM continuous variable-rate spray. International Journal of Agricultural and Biological Engineering. 6(4):1-8. Interpretive Summary: The quality of pesticide application is important for farming practice to uniformly cover the targets with a desirable thickness. To evaluate the quality, methods are needed to characterize the application distribution in field. The scientists at National Engineering Research Center for Information Technology in Agriculture (NERCITA), China and USDA-ARS Crop production Systems Research Unit, Stoneville, MS, have collaboratively conducted a study to develop a method to evaluate the distribution of variable-rate application. The results indicated that the graphic visualization in 1-, 2- and 3-D could provide collective information to completely describe the spray distribution. The study describes a method to completely evaluate the spray quality, and provides guidelines for operation of pesticide application in practice.
Technical Abstract: Chemical application is a dynamic spatial distribution process, during which spray liquid covers the targets with certain thickness and uniformity. Therefore, it is important to study the 2-D and 3-D (dimensional) spray distribution to evaluate spraying quality. The curve-surface generation methods in Excel were used to establish 1-D, 2-D, and 3-D graphics of variable-rate spray distribution in order to characterize the space distribution of the variable-rate spray. This study developed the 1-D, 2-D, and 3-D distribution graphs of PWM-based (Pulse-Width Modulation) continuous variable-rate spray to provide a tool to analyze the distribution characteristics of the spray. The 1-D graph showed that the spray distribution concentrated toward the center of the spray field with the decreased flow-rate. The 2-D graph showed that the spray distribution always spread as the shape of Normal Probability Distribution with the change of the flow-rate. The 3-D graph showed that the spray distribution tended to be uniform when the sprayer travelled forward at the appropriate speed. The study indicated that the visualization method could be directly used for analysis and comparison of different variable-rate spray distributions from different experimental conditions and measuring methods.