For the problem that, under the soybean-maize strip intercropping pattern, the installation of anti-drift shields changes the mass and inertia characteristics of the boom of a shielded sprayer, making it prone to severe vibration under complex field excitations and thereby affecting application uniformity and operational safety, a semi-active boom vibration damping system based on a magnetorheological damper was designed and tested. First, an equivalent mechanical model of the boom considering added mass and stiffness variation was established, and the characteristics of excitation sources such as road spectra and start-stop impacts were clarified. Second, based on the Bouc–Wen model, the magnetorheological damper was selected and its output force boundaries were designed. The stroke was determined to be 80–110 mm, and the maximum damping forces in the compression and rebound strokes were 1.15 kN and 3.44 kN, respectively. Furthermore, a semi-active vibration damping system with an LK3U-14MT PLC as the core controller was developed. Finally, simulation analysis, free-vibration decay tests, obstacle-crossing tests, and field operation tests were conducted to verify the vibration damping performance of the developed semi-active system. The field test results showed that, at typical operating speeds of 3–5 km/h, the semi-active vibration damping system reduced the maximum vertical amplitude at the boom tip by 28.6–43.1% and the maximum inclination angle by 12.2–55.6%, effectively improving the attitude stability and roll resistance of the boom of the shielded sprayer.

To meet the requirements of differentiated pesticide application between soybean and maize strips in soybean–maize strip intercropping systems, this study developed a strip-specific variable-rate spraying system based on real-time prescription map interpretation and spatiotemporal nozzle matching with delay compensation. A simulated prescription map with predefined application-rate levels was generated using ArcMap and converted into a binary data structure suitable for embedded-controller access. Based on high-precision RTK-BDS positioning information, a local field coordinate transformation model was established and combined with SRAM-based memory preloading to achieve rapid prescription matrix addressing. To reduce boundary misalignment caused by positioning offset, actuator response lag, and hydraulic delay during dynamic field operations, a nozzle spatial position prediction model and a forward delay-compensation control algorithm were developed. Results from the strip-specific variable-rate spraying tests based on the simulated prescription map showed that, under the tested conditions, the mean boundary offset decreased from 0.69 m to 0.29 m after delay compensation. The mean flow-rate control accuracy for both soybean and maize strips exceeded 95% across different application-rate levels, while the coefficients of variation of flow rate were below 6%. These results indicate that, under the tested conditions, the developed system was able to perform real-time prescription map interpretation, target application-rate matching, and strip-specific variable-rate control, demonstrating its technical feasibility for variable-rate spraying in soybean–maize strip intercropping.