Design and Exploitation of a Dual-Channel Direct Injection System

Soybean–maize intercropping is a traditional yet high-yield cultivation model that faces technical challenges in weed management due to the different herbicide requirements of soybean and maize. This study presents the design and experiments of the innovative dual-herbicide direct injection system, which can simultaneously deliver glyphosate and fomesafen through real-time concentration modulation. The system operates by measuring the relationship between the mixing ratio and the conductivity value, mathematical model, and control algorithm. Experimental validation demonstrated that the correlation coefficient of herbicide mixing ratios and measured conductivity values across pressure ranges of 0.1–0.3 MPa are greater than 0.98, which means that measuring the mixing ratio using conductivity is reliable. Optimal operational performance was achieved at 0.2 MPa spraying pressure, characterized by superior mixing uniformity (CV < 5%) and system stability. This technological advancement provides a practical solution for precision agrochemical application in complex cropping models, with potential applications extending to other crop combinations requiring differential herbicide treatments.