Design and experiment of seedling seperation device of Artemisia arborescens transplanter based on vibration mechanism

Abstract: The transplantation of Artemisia arborescens are mainly relying on artificial cuttings, the seedling separation device is a key component to achieve planting mechanization of Artemisia arborescens. In order to obtain orderly feed of Artemisia arborescens seedlings rod, a kind of seedling separation device of Artemisia arborescens transplanter based on vibration mechanism was designed in this paper. The main components of seedling separation device were: motor, frame, reset device of leaf spring, ledger plate, guide rail for seedling, seedling box, crank-rocker mechanism and transmission agent etc. At first, the device structure of seedlings was reasonably simplified to crank-slider mechanism, and the mathematical modeling was created on basis of characteristics of crank-slider mechanism. In order to achieve the best power transmission, the motion analysis of device was conducted，and the angular displacement, angular velocity, angular acceleration of coupler and rocker were obtained. The Matlab software was used to analyze the movement of the crank-slider mechanism, and then optimized the structure parameters of seedlings vibrating device. The optimization results showed that, when the coupler，rocker were 499mm and 273mm respectively, the power transmission could achieve the best results. Then, spring steel which was the key component of seedlings device was imported from Pro/E into Ansys Workbench to carry on model analysis of vibration characteristics. Model analysis results showed that, as frequency increasing, bending deflection of spring steel occurred firstly, then converted to distortion, and the superimposed vibrations which could lead to severe deformation appeared at last. Therefore, the vibration frequency should be less than 98.66 Hz, and the rigidity of upper end of spring steel should be appropriately strengthened. The crank length, vibration frequency and orbital inclination were taken as experimental factors, and then experimental studies of Artemisia arborescens seedling separation device were conducted. The results of the range analysis showed that the orbital inclination had the greatest impact on the quality of seedlings, the vibration frequency had less impact, and the crank length had a minimal impact. Therefore, the optimized combination was as follows: the vibration frequency was 36 Hz, the orbital inclination was 6°, and the length of crank was 14 mm. With this optimized combination, the qualified rate of seedling separation device based on vibration mechanism can reach 86.30%. This research work realized the mechanical seedling separation of Artemisia arborescens seedlings rod, which provided a reference for the further study of Artemisia arborescens transplanter.