Keywords
Spraying Uniformity
Droplet Density
Application Rate
Swath Width
Flight Speed
Abstract
Remotely Piloted Aircraft Systems (RPAS) offer fast, precise, and efficient application of pest control chemicals, playing a vital role in effective crop management. RPAS are a key innovation in mechanized agriculture, offering precise application of fertilizers and pesticides to reduce waste, minimize environmental impact, and enhance crop yield when combined with other modern farming practices. This study evaluates the spray uniformity of a remotely piloted aircraft system at different flight speeds (3 m/s and 5 m/s) to determine its effectiveness in aerial spraying applications. The experiment assessed droplet deposition, size distribution, and uniformity using water-sensitive paper (WSP) and the DepositScan software. Data were analyzed using descriptive statistics and an independent t-test to compare to treatments. Results indicate that droplet density and uniformity were highest at the center of the spray path, with greater dispersion occurring at the edges. The effective swath width was 8.8 m at 3 m/s and 8.0 m at 5 m/s, with coefficient of variation (CV) values of 10.45% and 17.72%, respectively, indicating variability in coverage. The RPAS achieved an output rate of 6–11 L/min, corresponding to application rates of approximately 39–47 L/ha. Higher flight speeds improve RPAS spraying efficiency but reduce spray quality, as increased speed (3–5 m/s) leads to smaller droplets and less uniform distribution. Optimizing flight parameters is key to balancing coverage and accuracy. This study highlights RPAS’s potential in enhancing spraying uniformity for precision agriculture, particularly in smart farming and mechanized rice production, and emphasizes the need for further research to optimize calibration, reduce drift, and minimize environmental impact.
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