ARS | Publication request: A Portable Pixel Recognition System for Evaluating the Distribution of Spray Deposits

Submitted to: Meeting Proceedings
Publication Type: Proceedings
Publication Acceptance Date: February 20, 2010
Publication Date: June 23, 2010
Repository URL: http://hdl.handle.net/10113/47313
Citation: Zhu, H., Salyani, M., Fox, R.D. A Portable Pixel Recognition System for Evaluating the Distribution of Spray Deposits. American Society of Agricultural and Biological Engineers International Meeting, June 20-23, 2010, Pittsburgh, Pennsylvania. ASABE Paper # 1008502.

Technical Abstract: Preventing over- or under–spray applications on intended targets require a feedback technology to improve the spray coverage efficiency. A portable scanning system was developed that could quickly evaluate spray deposit distribution on deposit collectors. The system is integrated with a handheld business card scanner, deposit collectors, a laptop computer, and a custom-designed software "DepositScan" to evaluate spray deposit distribution. The software is composed with a set of custom plug-ins that are used by an image-processing program (ImageJ) to produce a number of measurements suitable for describing spray deposit distribution. After scanning the collectors, individual droplet sizes, their distributions, total droplet number, and percentage of area coverage are displayed on the computer screen and saved in a spreadsheet. Spots smaller than 23.9 µm were ignored by DepositScan. Observations of nominal size spots through a stereoscopic microscope verified the accuracy of the system, and demonstrated that because of pixel limitations, the accuracy of any image-processing program using the pixel recognition technique would decrease as the spot sizes decrease. The portable scanning system offers a convenient solution for on-the-spot evaluation of spray quality under various working conditions.