Design And Experiment Of Wheel Spoon Precision Seeder For Panax Notoginseng

Panax notoginseng is one of the important and precious Chinese medicinal materials in China,as well as a famous authentic medicinal material in Yunnan Province.More than 98%of Panax notoginseng in China is produced in Yunnan province.According to incomplete statistics,the planting area of Panax notoginseng in 2017 has exceeded 66666.7 hm².But the level of mechanized sowing of Panax notoginseng is relatively low,the main planting pattern is through manual operation,which is not only labor intensity,high cost and low quality of operation,therefore,the development of a precision planter for Panax notoginseng sowing is imperative,According to the characteristics of Shady planting of Panax notoginseng in Yunnan province and the poor fluidity and vulnerable seeds of Panax notoginseng,combined with the agronomic requirements of Panax notoginseng planting,the plant row spacing should be about 50 mm.Considering the characteristics of high cost and large power equipment of pneumatic precision seeder,as well as the problems existing in the existing mechanical precision seeder,such as poor filling effect and easy to damage the seed,a wheel-spoon type Precision seeder of Panax notoginseng was designed to improve the sowing efficiency of Panax notoginseng.The research contents are as follows:（1）Design of wheel scoop type precision seed metering device for Panax notoginseng.According to the planting agronomy requirements of Panax notoginseng in Yunnan Province,a precision seed metering device of panax notoginseng was designed.The three-dimensional model of the seed metering device of panax notoginseng was established by NX software,and the working principle of the seed metering device was expounded and the relevant structural parameters were analyzed theoretically to determine the overall structure of the seed metering device.（2）Based on EDEM software,a single factor simulation experiment was carried out for the wheel-spoon seed metering device.The NX software was used to build a 3d model of the wheel-scoop type seed distributor.The simplified parts that did not participate in the simulation in the 3D model were exported to STL format and imported into EDEM software as the simulation model of the wheel-scoop type seed distributor.The number of seed spoons,the rotation speed of seed wheel,the height of seed layer and the hole radius of seed scoop were analyzed by single factor simulation test.With the conformity index,leakage charging index and recharging index as test indexes,the best conformity index range of seed metering apparatus is greater than 90%.The optimal range of experimental factors was determined as follows:the number of seed spoons was 18,the rotation speed of seed picking wheel was 15.0～30.0 r·min^-1,the height of seed layer was 100.0～150.0 mm,and the hole radius of seed spoon was4.0～5.5 mm.（3）The best working parameters were determined by testing the wheel spoon seed metering device on a bench.Taking the rotation speed of the seed wheel,the height of the seed layer and the radius of the seed scoop hole as the test factors,and taking the qualified index,recharge index and leakage index as the test indexes,the combined bench test of quadratic regression orthogonal rotation was carried out.The regression models of the qualified index,leakage index and leakage index were established,and the parameters of the regression model were optimized.The test results show that the main order of influencing the conformity index is the rotation speed of seed wheel,seed layer height and seed scoop hole radius.When the seed scoop hole radius was4.75 mm,the rotation speed of seed wheel was 15.0～20.0 r·min^-1,and the seed layer height was 113.0～139 mm,the qualified index was more than 95.0%,the leakage filling index was less than 4.0%,and the recharge index was less than 1.0%,meeting the planting requirements of panax notoginseng.（4）This paper selects the pressure roller pressure hole,Through theoretical analysis,combined with the agronomic requirements of Panax notoginseng seed sowing in Yunnan Province.The diameter of the pressure roller is set to 300 mm.There are 18 pricking hole column designed on the pressure roller.The bottom side length of the pressure column is 40 mm,the slope is 30°,and the height is 25 mm.Combined with kinematic analysis,it was obtained that the acceleration of the pressure roller was proportional to the distance between the center of the pressure roller and the center of the cave column,and the rotation angle of the pressure roller during the cave pressing process.The motion analysis of the Panax notoginseng seeds at the seed placement was carried out.Combined with the pre-test before design and considering the processing problem of the prototype,the projection distance from the central line of the seed metering device to the central line of the pressure roller was set as 500 mm,and the dropping height of the seed metering device was 60 mm.（5）Whole machine design and prototype processing of wheel spoon precision seeder for Panax notoginseng.The working principle of the whole machine of the seeder was expounded,and the optimized parameters were used as working parameters to conduct a field experiment on the seeder,so as to verify the working performance of the wheel-spoon type Panax notoginseng precision seeder.According to the problems existing in the actual experiment,the seed metering device was optimized to a certain extent.After optimization,the experiment was again conducted,and the results showed that it met the requirements of Panax notoginseng sowing in Yunnan Province of China.