Submitted to: Computers and Electronics in Agriculture
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/21/2009
Publication Date: 5/1/2009
Publication URL: http://hdl.handle.net/10113/32443
Citation: Kim, Y., Evans, R.G. 2009. Software Design for Wireless Sensor-based Site-specific Irrigation. Computers and Electronics in Agriculture. 66(2):159-165. Interpretive Summary: Irrigation is critical in a cropping system, and efficient water management is required to maximize productivity and minimize environmental impact. A sensor-based irrigation system was developed to automate site-specific irrigation via wireless communication. The system has been running since the 2005 growing season and is still being used for our various projects on soil and water management research. Software development was initiated after extensive study and verification of system components such as sprinkler control, sensor calibration, and radio communication. This manuscript was focused on details of software design to support a closed-loop control system for site-specific irrigation. The software integrated a site-specific irrigation controller with in-field data feedback, enabling real-time monitoring of field conditions and remote access to the irrigation controller via user-friendly graphical user interface. The benefit of the developed software extends to automation of site-specific agrochemical applications.
Technical Abstract: In-field sensor-based site-specific irrigation management is of benefit to producers for efficient water management. Integration of the decision making process with the controls is a viable option for determining when and where to irrigate, and how much water to apply. This research presents the design of decision support software and its wireless integration with an in-field wireless sensor network (WSN) to implement site-specific sprinkler irrigation control. In-field micrometeorological information is fed from the distributed WSN and displayed on a geo-referenced field map on a base station. A self-propelled linear irrigation system is remotely controlled by the base station for variable rate application at 15 different banks of sprinkler nozzles. The decision making process supports site-specific water application based on the percentage of 60-sec nozzle duty cycle that is a function of the feedback from the soil water content sensors from the WSN. An algorithm for nozzle sequencing was developed to stagger nozzle-on operations so that timeslots are evenly distributed over the 60-sec cycle so as to minimize pressure surges.