Double-Setting Seed-Metering Device for Precision Planting of Soybean at High Speeds

摘要

Precision planting has been proven to be an effective methodfor seeding row crops with uniform seed spacing, which favors crop yields. However, most precision planters were developed for low field operating speeds. In this study, a mechanical seed-metering device was developed with double-setting seed pickers, which allows high-quality planting at high field operating speeds. A discrete element model (DEM) was used to examine the effects of the design parameters on the metering performance, as indicated by the quality index (Iq), miss index (ImiSS), and multiples index (Imii). Based on the model results, a seed-metering device was fabricated with the optimal design parameters and tested in laboratory conditions for model validation. Results showed that the critical parameters for the seed picker design were the lengths of the first and second setting plates (Lj and L2, respectively) and the seed cell and seed holder angles (a and ft, respectively). The Iq was generally high and the Imiss and Imun were generally low over the ranges ofLj from 15.5 to 17.5 mm, L2 from 4.6 to 5.5 mm, afrom 57.5° to 65.0°, and0from 50.0° to 70.0°. The most influentialfactors were pandL2 and their interactions. The best performance, represented by the highest Iq, occurred at L2 = 5.18 mm and fi = 61.9°, where the Iq was 99.59%. The model results agreed well with the test results, as demonstrated by the low relative error (2.5%).