Disturbance analysis and seeding performance evaluation of a pneumatic-seed spoon interactive precision maize seed-metering device for plot planting

In response to the serious issue of missed seeding of the seed-metering device caused by the small and gradually decreasing number of maize seeds in plot planting conditions, a precision seed-metering device for maize plots with pneumatic-seed spoon interactive was designed. The seed-metering device utilises the coupling interaction between the seed spoons and airflow to adjust the maize posture in the filling zone, achieving stable filling of the seed-metering device with a low population of seeds in the seed chamber. EDEM software is used to simulate and analyse the disturbance caused by three types of seed-metering discs and the average kinetic energy in the filling zone as the evaluation criterion. A test platform for seed-metering device of maize plot was constructed, with the qualified index, multiple index, and missing index as evaluation criteria. A full-factorial experiment was conducted with rotation speed of the seed-metering disc, air pressure, and types of seed-metering discs as factors, determining the optimal seed-metering disc for seeding performance. The results indicated that under conditions of low seed population in the seeding chamber, with air pressures ranging from −1.5 to −2.5 kPa and seed-metering disc speeds between 1.16 and 3.49 rad s⁻¹, the seed-metering device with linear disturbance exhibited a multiple index of <6.25% and a missing index of <3.46%. Additionally, the qualified index consistently reached 90.29%. These evaluation criteria meet the standards, demonstrating effective seeding capabilities.