Study of a Designed Low-Damage Conveying Device for Maize Seeds

Abstract

The performance of intelligent seed sorting systems is highly dependent on efficient, high-quality, singulated seed conveyance, a prerequisite for reliable image recognition. To address the prevalent issues of seed overlap, low efficiency, and physical damage in traditional mechanical or vibratory feeders, this study developed a low-damage seed conveying device for maize seeds based on the negative pressure adsorption principle. An innovative seed disturbing mechanism with semi-circular concave columns was designed. Discrete Element Method (DEM) simulations confirmed that this structure significantly enhances seed population fluidity and the probability of seed-orifice contact. Integrating Computational Fluid Dynamics (CFD) with multi-objective optimization, which combined orthogonal experimental design and response surface methodology, allowed for the optimization of the negative pressure chamber's key parameters. This process identified an optimal configuration: a negative pressure chamber port location of 35.6°, an orifice diameter of 4.5 mm, and a flow channel diameter of 29.6 mm. This configuration achieves an optimal balance across the adsorption, seed conveyance, and desorption stages. Bench tests demonstrated that the optimized device attains an average seed singulation success rate of 96.16% with stable performance. Owing to the non-contact negative pressure adsorption principle, physical seed damage was negligible, substantially lower than the 11.4% rate caused by traditional vibratory feeding. Furthermore, the ordered seed flow increased the back-end image recognition system's overall classification accuracy from 85.5% to 97.0%. This research provides an efficient and low-damage technical solution to the front-end conveying bottleneck in intelligent seed sorting.