| In recent years,how to improve the planting efficiency of sweet potato and reduce the labor cost has become urgent problems to be solved with the increase of sweet potato planting area.But for the bare sweet potato seedlings physiological characteristics of interwoven branches and leaves and large morphological differences leads to all the existing transplanting techniques require to divide and supply seedlings manually,which seriously restricts the operation efficiency of sweet potato transplanting machinery.According to this situation,a linear automatic seedling feeding sweet potato transplanter is developed which combined with the linear seedling feeding and transplanting mode.In order to realize the full-automatic mechanization of sweet potato transplanting,the machine can complete multiple operation links such as automatic seedling feeding,furrow planting,soil covering and ridge repair of two ridges of sweet potato at one time.which is of great practical significance to promote the development of mechanized sweet potato transplanting technology.The main research contents of this paper are as follows:1)Characteristic analysis and trial production of linear sweet potato seedlings.According to the agronomic requirements such as planting mode and transplanting mode in the process of potato seedling transplanting,and to meet the relevant requirements of automatic seedling feeding of transplanter,it was determined that the transplanter adopts the linear seedling feeding transplanting mode,and a linear sweet potato seedling was designed for this transplanting mode;The physical and mechanical characteristics of linear sweet potato seedlings were analyzed to provide reference for the design of seedling feeding mechanism of subsequent transplanter;According to the structural design and production scheme of linear sweet potato seedlings,the preliminary design of linear sweet potato seedling production machinery was carried out to realize the mechanized mass production of linear sweet potato seedlings.2)Scheme design of the whole machine of the linear automatic seedling feeding sweet potato transplanter.Determine the overall design scheme of the transplanter,and its forward mode is traction type,which is mainly composed of synchronous transmission mechanism,linear seedling supply mechanism,trenching seedling planting mechanism and soil covering and ridging mechanism.3)Design and analysis of key components.The synchronous transmission mechanism,linear seedling supply mechanism,trenching seedling planting mechanism and soil covering and ridge repairing mechanism were theoretically analyzed to determine the main design parameters.As the core part of transplanting and seedling feeding technology,the linear seedling feeding mechanism was analyzed by ANSYS finite element method to verify the rationality of structural design;In the research and development process,the trenching seedling planting mechanism was mainly designed.Based on the theoretical analysis and edem discrete element simulation,the structural parameters and working parameters of the trencher were optimized by using the methods of four factor three-level orthogonal test and orthogonal extreme value analysis;According to the agronomic requirements of sweet potato ridge transplanting,the combination design of soil covering and ridge trimming mechanism was carried out to meet the requirements of soil covering and ridge trimming after sweet potato ditching and seedling planting.4)Prototype manufacturing and field test.According to the design requirements,the prototype of the transplanter was trial manufactured,and the sweet potato transplanting field test was carried out.The test results show that when the transplanter maintains the speed of 0.7 m/s,the average plant spacing of the machine is 151.6 mm,the qualified rate of plant spacing is 100%,the qualified rate of planting depth is 79%,the qualified rate of oblique insertion is 85%,and the seedling leakage rate is 2.6%,which meets the requirements of sweet potato mechanical transplanting. |
PDF Full Text Request