Research On The Technology Of Regulating The Orientation Of Seed Buds During Single Seeding Of Garlic

As an important condiment with rich nutritional value and health and medicinal value,garlic is popular among the public,and the planting area increases year by year.China is the largest producer and consumer of garlic,with a garlic planting area of more than 900,000hm~2 according to statistics.Mechanized sowing has become an inevitable trend,but the level of mechanized garlic Mechanized sowing in China is still at a low level,due to the strict agronomic requirements of garlic planting,i.e.,"single grain sowing,root down and bud up,upright and planting depth consistent".The existing garlic sowing machines have a low qualification rate of single grain seeding,low qualification rate,poor adaptability of garlic clove orientation adjustment,and low uprightness in directional sowing.These are the main factors that hinder the promotion of mechanized garlic sowing in China.This study took garlic as the research object and aimed to solve the problems in garlic seeder.The key structure and parameters of the wheel and spoon single-seed extraction device were optimized with the help of discrete element simulation technology and a mathematical model.Also,the method of improving the qualification rate of single-seed extraction by wheel and spoon single-seed extraction device was studied.Besides,three characteristic parameters of garlic clove orientation were extracted by analyzing garlic images,and a garlic clove orientation adjustment test bench was built with the Lab VIEW platform to verify the effectiveness of the pushing garlic clove orientation adjustment method.The edge computing processor Jetson Nano and convolutional neural network were used to adjust the garlic clove orientation.This solves the problem of the insufficient computing power of the embedded processor and the large size of the industrial control machine and provides a reference for deploying the intelligent garlic clove orientation adjustment device at the product end.Additionally,the mechanism of the interaction between garlic-inserter-soil was analyzed from the microscopic perspective through discrete element simulation analysis and bench test.This provides a theoretical basis for improving the uprightness of garlic planting.The main contributions of this study are summarized as follows.(1)The wheel and spoon single-seed extraction device was studied.Through the stress analysis of garlic in seed taking area,seed conveying area,and seed metering area,the mechanism of single garlic seed taking with wheel spoon was investigated.The optimal structure of the seed scoop and seed-taking wheel was determined by comparison and optimization through discrete element simulation analysis.Based on the normal distribution data of the three-dimensional size of the garlic clove,the mathematical model of the key size of the seed picking scoop was established,and the size range of a single seed picking scoop was determined by the graphic method.Through theoretical analysis,a wheel spoon type garlic single seed collection test-bed was built.The orthogonal regression test was conducted,with the radius and length of the seed picking scoop and the speed of the seed picking wheel as the test factors,and the leakage rate and qualified rate as the response indexes.Besides,the regression model of leakage rate and the qualified rate was established,and the parameters of the model were optimized.(2)The adjustment device based on machine vision for garlic clove direction was designed and tested.By analyzing garlic clove images,three feature parameters that are closely related to garlic clove orientation were proposed,and a multi-feature parameter fusion method was used to obtain the comprehensive feature parameters for recognizing garlic clove orientation.The correctness and adaptability of the garlic clove orientation recognition method were experimentally verified by using MATLAB.Based on the research on the garlic clove orientation recognition method,a machine vision-based lateral push garlic scale bud orientation adjustment device was designed.Meanwhile,the mechanism of garlic clove orientation adjustment was analyzed,and the hardware and software systems of the device were designed on the Lab VIEW platform.Besides,a test bench was built to verify the effectiveness of the device for garlic clove adjustment.(3)The garlic clove orientation adjustment device was designed and tested by using the Jetson Nano processor.The automatic garlic clove orientation adjustment device was designed,and the mechanism of the garlic clove orientation adjustment device was analyzed.Meanwhile,the discrete element model of the garlic clove orientation adjustment device was established,and the key structural parameters of the device were optimized through simulation analysis in combination with orthogonal tests.In terms of the control algorithm,to reduce the model complexity and improve the real-time judgment of garlic orientation,a dual convolutional neural network model was used for garlic clove feed detection and garlic clove orientation judgment.Jetson Nano,an edge computing processor from NVIDIA,was used as the core of the control system,and the NVIDIA Tensor RT acceleration library was used to reason about the convolutional neural network model,reconciling the computing power and volume of the controller.The device was validated in a bench test using a hybrid garlic clove as the test object.(4)The interaction mechanism between garlic clove,inserter,and soil during directional planting was investigated.The working mechanism of double duckbill type directional inserter was analyzed,and the discrete element model of garlic-inserter-soil interaction was established.Based on this,the working process of intermittent insertion and continuous insertion were simulated and analyzed to reveal the interaction mechanism between garlic clove,inserter,and soil during directional planting.The effects of insertion depth,lifting height,insertion speed ratio,and soil particle surface energy on insertion uprightness and planting depth consistency were analyzed.Besides,a testbench was built on Labview to experimentally validate the analysis results.The simulation and test results showed that:(1)insertion depth,lifting height and insertion speed ratio have direct influence on planting uprightness,and these parameters can effectively improve planting uprightness only if they are coordinated with each other and have reasonable values;(2)the surface energy of soil particles has a greater influence on planting uprightness,and the smaller the surface energy the higher the uprightness.