| Transplanting of vegetable have a lot of advantages. For instance, it can facilitate maturityand get fertility, increase multiple cropping index. Also it is easier for centralized management,at the same time, transplanting could precaution against natural disasters, economize vegetableseeds and cause lower costs. Vegetable transplanting technology is benefited to vegetableindustry. So impact and risk of vegetable industry caused by natural disasters can be minimized.The application of vegetable transplanting technology could reduce the labor intensity, increaselabor productivity, ensure operational quality and achieve the targets of vegetable’s production.Automatic vegetable transplanter is the development direction of vegetable transplanting, whichbrings low-intensity work and high efficiency. Performance of the fully automatic vegetabletransplanter is influenced by the picking seedling mechanism, which is the critical component offully automatic vegetable transplanter. Therefore, the research of picking seedling mechanism islaunched, which is of positive significance.The specific contents of this paper are as follows:(1) Design scheme of each major part of picking seedling mechanism has been formulated,which is based on characteristic of working object and performances of working mechanism.Working principle and theoretical model of picking seedling mechanism have been presented andsystematically analyzed. As the same time, a new method of establishing non-circular gear pitchcurve equation has been proposed.(2) Optimization software of picking seedling mechanism has been developed, which isbased on theoretical model and Visual Basic6.0. Interface and function of human-computerinteraction software has been introduced. Parameters optimization of picking seedlingmechanism has been completed after the adjustment of parameters gotten by the theoreticaldesign requirement, and then these vital parameters have been outputted.(3) The geometric parameter design of the non-circular gear has been finished after theconfirmation of structure parameters, which were obtained through optimization software. A newtype of non-circular gear has been put forward, which can output high and non-uniform transmitting ratio.(4) Physical design of picking seedling mechanism has been carried out after analyzing thedrawbacks of the prior art, which including the drive part and picking seedling arms. Thenimproved design of several key parts in picking seedling mechanism have been finished, mainlyincludes device of eliminate backlash and picking seedling claws.(5) Three-dimensional entity model and3D model assembly of picking seedling mechanismhave been finished with the help of UG8.0. Also the virtual prototype has been tested with thehelp of ADAMS. Feasibility of new type of non-circular gear and reliability of new pickingseedling mechanism have been verified by analyzing the working trace, velocity curve of pickingseedling claws cusp and force situation of sun gear, etc.(6) Manufacture and fitting of picking seedling mechanism have been fulfilled. Thus,reliability of new picking seedling mechanism has been further identified after completing thetest of kinematics characteristics and effect of working.Parameters are easy got by means of own software, which could meet requirement of design.Accuracy and reliability of picking seedling mechanism of planetary gear train with non-circularand elliptical gear have been verified by the theoretical analysis, the physical design, entityprocesses and physical experiment. Finally, picking seedling mechanism of planetary gear trainwith non-circular and elliptical gears has been adapted to high speed operation by the virtualprototype test and the test. |
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