Click on “Download PDF” for the PDF version or on the title for the HTML version.

If you are not an ASABE member or if your employer has not arranged for access to the full-text, Click here for options.

Abstract. Recently, the design process of the air suction precision seed metering device for small round seeds is mostly simulated by the discrete element software. To study the physical parameters and mechanical properties of small round seeds and explore the uniformity of similar seeds. Three kinds of seeds (i.e., millet, rapeseed, and broomcorn millet) were selected and their 1000-grain weight, triaxial sizes, density, and angle of repose were measured and the uniformity of those three kinds of seeds was analyzed. According to the distribution of their equivalent diameter, each kind of seeds were divided into three specifications (i.e., large, medium, and small) by using customized mesh screen and the seeds with moisture content of 13%, 18%, and 23% were made for the study of seed properties and the experiment of seed metering device. The static friction coefficient and dynamic friction coefficient of seed board with wood board, acrylic board and stainless steel board were measured by inclinometer and friction and wear testing machine. A high-speed camera system was used to build the experimental platform and the collision recovery coefficient of seeds was studied by the free falling collision method. The experiments carried out at three heights of 10cm, 20cm, and 30cm, the collision recovery coefficient decreased with the increase of height. Three materials of different hardness were used for experiments, the harder the impact material was, the greater the collision recovery coefficient was. It provides necessary parameters for simulation of air suction precision seed metering device of small round seeds.