Design and Preliminary Evaluation of a Precision Cylindrical Air-Assisted Drill Sowing Device for Rapeseed, Wheat, and Rice

To address challenges in seed feeding stability and seeding uniformity in agricultural practices, this study aimed to introduce a cylindrical air-assisted drill sowing device (CADSD) designed for rapeseed, wheat, and rice (RWR). The device features a prototype hill-feeding mechanism that addresses problems related to seed feeding, airflow disruptions, and seed–wall collisions. Comprehensive bench tests, Discrete Element Method (DEM) simulations, and preliminary field experiments were conducted to evaluate the seed-feeding stability characteristics and optimize the structural parameters of the air-assisted drill sowing system, enhancing seeding uniformity and operational efficiency. The optimal operating speed range is between 4 and 5 km/h. When the seed feeding speed is 30 to 38 r/min, the coefficient of variation of the seed supply rate stability is less than 0.55%, and the relative error between the theoretical and the experimental actual values of the RWR supply rate regression model is less than 2%, further supporting the effectiveness of the device. A preliminary field test revealed a seeding uniformity coefficient of variation (CV) of 3.44% and an emergence rate of 88%, closely aligning with the desired metrics. The CADSD effectively sows multiple crop types with improved precision and uniformity, handling diverse seed types and sizes without requiring equipment modifications, highlighting its innovative impact on agricultural technology in the precise seeding of RWR.