| Transplanting is one of the most important links in the process of vegetables production.Mechanized transplanting is the main means to reduce labor intensity,improve production efficiency and achieve large-area planting.It is also an urgent problem that needs to be solved in China's vegetable growing industry.T ransplanting mechanism as an important executive part of vegetable transplanting machine,its operation performance will directly affect the quality of transplanting.Therefore,to find a transplanting mechanism with stable operation and excellent performance has been a key and a difficult point in the research of transplanting equipment.Compared with the transplanting operation method of seedling picking and planting separately from the existing transplanting machine,the transplanting machine for integration of picking and planting has a compact structure,small working space,and no mistakes in connection with the seedlings sending,which is beneficial to improve the transplanting success rate,while it put forward higher requirements for the transmission ratio,trajectory and posture of the transplanting mechanism.For this purpose,with the support of the National Natural Science Foundation of China,the research on the subject structure,dimension and experiment was carried out in this paper.The author analyzed the existing transplanting mechanism and its design method,and proposed a design method for the vegetable pot seedling transplanting mechanism of the double-planetary based on positioning posture,and designed a vegetable seedling transplanting mechanism that can complete a series of actions such as picking seedlings,sending seedlings and planting seedlings etc.,and which was used for the transplanting operation of broccoli seedlings.The main contents of this article are as follows:1)The author analyzed the research status of vegetable seedling transplanting mechanism at home and abroad,and summarized the limitations of transplanting mechanism and their design methods.In order to obtain a larger ratio of the total transmission ratio to meet the requirements of the trajectory shape and posture of the transplanting trajectory,a double-planetary transplanting mechanism for cam-non-circular gear combination transmission was proposed to break the configuration limitation of the existing transplanting mechanism,which was used for transplanting broccoli seedlings.2)According to the requirements of transplanting agronomics,the trajectory and the posture of the end of the seedling claw at a specific position(clamping point,pulling seedling point,pushing seedling point,and some point of the returning process)were planned.In the process of mechanism kinematics synthesis,in order to enable the transplanting arm point to pass through a set of positions,the mechanism was simplified into an open-chain 3R mechanism by removing the gear and cam pair constraints,and the model of the open-chain mechanism based on the precise four-position was established,and the fixed hinge point(central point)and the dynamic hinge point(dot)curve,that is,the Burmester curve,were obtained.The length ratio analysis of adjacent bars was used to determine the feasible area of the center point curve and the dot curve and the reasonable length of the open chain mechanism.3)According to the transmission characteristics of the double-planetary picking and planting integrated vegetable pot seedling transplanting mechanism,the kinematics model was established,and the calculation and distribution model of the cam and non-circular gear ratio was established.Combining the technical characteristics and agronomic requirements of vegetable seedling transplanting,the design requirements of transplanting mechanism were put forward.Based on the GUI platform of MATLAB,the auxiliary analysis and calculation software of double-planetary vegetable pot seedling transplanting mechanism with cam non-circular gear combination was wrote,and the parameters of transplanting mechanism were optimized.4)The structure of the transplanting mechanism was designed with the obtained mechanism parameters,and the transplanting mechanism was simulated and tested in the ADAMS software.The high consistency of the theoretical transplanting trajectory and simulation trajectory of the vegetable pot seedling transplanting mechanism was verified.Finally,a transplanting mechanism was produced,and the experiment platform was set up for the picking and transplanting experiment.Ansysising of the test results provides a reference for future generations. |
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