Design and testing of the vibrating type cell-belt precision seed metering device for super hybrid rice

Abstract

In order to meet the requirements of low volume and high precision in the seeding process of super hybrid rice, a vibrating type cell-belt precision seed metering device was designed. To optimise the seed filling performance, a vibration plate with grid was integrated into the seed box. The structural parameters of the vibration plate were designed according to the dimensions of the cell and seed. Mechanical and kinematic theoretical analyses of the seed filling process were conducted. Single factor analysis was employed and the structural parameters of the seed metering device were determined. The inclination angle of the cell-belt was 43°, and the vibration plate was installed where the difference in elevation between the lower end of the vibration plate and the bottom of the seed box was 0 mm. A Box-Behnken test was conducted to establish quadratic regression models between the factors, which included the working speed of the cell-belt, amplitude and frequency of the vibration plate, and the test indicators, which included qualified rate, multiple rate and leakage rate, then the significance analysis was carried out. The results of the multi-objective optimisation indicated that the seed filling performance was optimised when the working speed of the cell-belt was 0.088 m·s⁻¹, the amplitude and frequency of the vibration plate were 1.056 mm and 10.278 Hz, respectively. The qualified rate, multiple rate, and leakage rate were experimentally validated at 95.27 %, 3.92 %, and 0.81 %, which is in accordance with the requirements of super hybrid rice precision seeding.