A Novel S-section control hose–reel machine for variable rate fertigation

Abstract

This study presents the development of a cloud-based, automated variable-rate fertigation system by modifying an existing hose–reel irrigation machine (HIM). A 46-m-wide HIM spraying boom was segmented into four independently controlled sections, and a 300-L fertiliser tank was mounted on the spraying cart to deliver liquid fertiliser directly into each section line. A control system, programmed in C#, was designed to automate the application of irrigation water and fertiliser. Calibration through laboratory and field tests optimised the application accuracy. A cloud-based information and communication technology platform was developed. The soil moisture data from the LSE01 sensors were transmitted via LoRaWAN to field gateways and then to the Things Network (TTN) for authentication, routing and JSON conversion. The system achieved precise irrigation and fertilisation within 15–50 mm and 80–600 L/ha, respectively, with minor errors (3–5% for irrigation, 1–3% for fertilisation). The spatial resolution improved significantly, with the lateral resolution reduced from 46 m to 10.7 m and the longitudinal resolution increased from 0.17 to 1.5 m, depending on the desired irrigation water and liquid fertiliser rates. These results demonstrate that the developed hose–reel variable-rate fertigation machine offers accurate and efficient fertigation suitable for precision agriculture.