Development of a closed-loop irrigation system for sugarcane farms using the Internet of Things

•Integration of the automated irrigation system and the decision support tool.•Uplink automatically uploads irrigation and rainfall data to the decision support tool.•Downlink incorporates practical limitations and automates irrigation scheduling.•An increase in profitablilty with production unchanged. Better irrigation practices, through increased water use efficiency, can deliver economic, environmental and social benefits to agro-ecological systems. Increasingly, farmers world-wide are turning to automated irrigation systems to save them a significant amount of time by remotely turning on and off pumps and valves. Unfortunately, automated irrigation systems on their own do not provide insight on (i) the amount and timing of irrigation required by the crop or, (ii) how irrigation schedules should change with soil type, farm management and climate. To unravel these complex interactions, an irrigation decision support tool is needed. However, due to the high frequency of irrigations across dozens of irrigation blocks, and the need to irrigate almost all year-round, irrigation decision support tools can be very tedious and time-consuming for farmers to use daily. For these reasons, many farmers will not adopt these tools, and in doing so, fail to optimise irrigation use efficiency due to the multi-factorial nature of the farming system. This paper describes a cybernetic closed-loop solution that was piloted on a sugarcane farm in north-eastern Australia. The solution seeks to improve irrigation management by seamlessly integrating the WiSA automated irrigation system with the IrrigWeb irrigation decision support tool. Specifically, an Uplink program and a Downlink program were implemented in the pilot study. The Uplink program saved the farmer a significant amount of time. Instead of the farmer manually entering in records, Uplink uploaded irrigation and rainfall data directly to the irrigation decision support tool. The Downlink program calculated and applied irrigation schedules automatically using IrrigWeb, but also incorporated practical constraints, such as energy, pumping capability, irrigation priorities and farmer irrigation preference. The simulation results demonstrated that the developed closed-loop solution could effectively manage irrigation scheduling by incorporating irrigation decision support tools with practical constraints. Systems that increase water use efficiency can deliver practical, profitable and environmental benefits to irrigated