| At present,the transplanting technology of Scallion is relatively backward in China.Given the current situation and agronomy of Scallion transplanting,it is of great significance to develop a flexible disc automatic transplanter for Scallion,which is suitable for China’s national conditions,in order to improve the level of Scallion transplanting machinery,reduce manual labor and realize the modernization of agricultural development.In China,the transplanting of Scallion is mainly semi-automatic and manual,among which the transplanting efficiency of manual transplanting is low,and the transplanting effect is poor.The cost of Manual Transplanting increases year by year with the increase of labor cost.The existing semi-automatic transplanting machine on the market still needs to separate seedlings manually,the quality of which is poor,and plant spacing consistency after transplanting is poor.Given the shortcomings of the current Scallion transplanting machine,this paper designs a flexible green onion transplanter with simple operation,high transplanting efficiency,and good planting effect.It carries out the critical technology research and performance test of the transplanter.The main contents and results are as follows:(1)In view of the problems faced by the development of scallion transplanter in China,and combined with the research status of scallion transplanter at home and abroad,the design and development were carried out to achieve the goal of high efficiency,high quality and low damage of automatic transplanting of scallion seedlings(2)The development of onion seedling automatic transplanting involves soil,onion seedling,mechanical design,and many other aspects,and each link needs to be connected to solve the problem better.To make the mechanism design of the green onion transplanter more reasonable,the physical characteristics of green onion seedling and bowl were measured,and the soil characteristics in northern China were measured to provide help for the design of the transplanter.(3)In order to ensure the automation of green onion transplanting,the transplanting mechanism of the green onion transplanter not only needs to continuously complete the actions of throwing,receiving and releasing,transporting,and transplanting seedlings but also meets the agronomic characteristics of green onion seedlings,such as plant distance,transplanting depth and verticality,the transplanting distance was 40 ～ 60 mm,the transplanting depth was50 ～ 130 mm,and the transplanting frequency was 270 plants/min.(4)This paper designs the transplanter’s picking and throwing mechanism,expounds the mechanical structure and working model of the mechanism,establishes the mathematical motion model of the mechanism,and optimizes the motion speed and structural parameters of the mechanism by using ANSYS combined with the physical characteristics of onion seedling and bowl body.The diameter of the seedling throwing rod is set to 7 mm,and the ejection speed of the seedling rod is set to 0.041 m/s.The kinematics model of the seedling picking mechanism is established based on the screw theory,and the simulation analysis of the seedling picking mechanism is carried out by using ADAMS.The working space of the seedling picking mechanism is calculated by using the Monte Carlo algorithm,and the point cloud diagram of the seedling picking mechanism is drawn,which provides the basis for the optimization analysis of the seedling picking mechanism.(5)Design the seedling device,study the characteristic parameters of the device and the movement track of onion seedling in the disk,put forward the optimization method of the device,establish the virtual test-bed based on ADAMS for the device,verify the motion parameters of onion seedling and calculate and analyze the convergence angle of the disk,select the operation speed of the transplanter,the convergence angle of the disk,and the angular velocity of the disk The single factor experiment showed that the three factors all affected the verticality of onion seedlings after transplanting.The orthogonal experiment was carried out in onion seedlings transplanting by selecting three levels of flexure plate polymerization angle,three levels of transplanter running speed,and three levels of flexure plate angular speed.It can be concluded that the most significant factor affecting the verticality was the transplanter running speed,followed by the flexure plate angular speed,and the flexure plate polymerization angle had a minor effect on the verticality. |
