Design And Optimization Of Harvesting Components Of Self-propelled Cabbage Harvester

Cabbage is a common bulbous vegetable,which is rich in nutrients.Originated in the northern rock of the Mediterranean Sea,it is currently cultivated throughout China.Currently,the harvesting of cabbage in China still relies mainly on manual operations.Low operational efficiency,high production costs,and high labor intensity are currently the main difficulties.Aiming at the above difficulties and combining with the actual production of cabbage in China,based on the research of physical and mechanical properties of cabbage,combined with virtual prototype technology and field experiments,this paper developed a cabbage harvesting component to meet the urgent needs of cabbage production mechanization.The main research content of this article includes the following aspects.（1）Study on physical and mechanical properties of cabbage.Randomly select 10soil samples from cabbage cultivation soil for collection,and measure soil physical properties through instrument and ring knife method;By selecting a certain amount of cabbage at harvest time,the shape data such as extraction power,height,heading size and quality,root stem length and diameter were measured;The mechanical parameters such as shear strength were measured through shear tests and crushing tests.The results showed that the soil moisture was（20.19±4.9）%,the soil strength was（11.9±4.6）kg·cm^-2,and the soil bulk density was（1.26±0.4）g·cm^-3;The average extraction force is 191.75N;The shear test result is:F_剪=1.8131x²+31.374x+2.0673,with a determination coefficient of 0.9966,F_挤=0.1654x2+23.802x+66.846,with a determination coefficient of 0.9995;（2）Design of harvesting components for self-propelled cabbage harvester.Based on the study of cabbage mechanics,the overall scheme design of the harvesting component process flow was carried out.Determine the diameter of the disc knife as300 mm,the overlap as 2 mm,and the center distance as 298 mm.The angle between the normal reaction force of the disc on the cabbage root and the X-axisαis 30.6°.A clamping and conveying device is designed,which adopts double conveyor belts arranged longitudinally and has an adjustable center distance of 450-500mm.Optimization experiments based on virtual prototyping technology.Modeling cabbage harvesting components through Solidworks,and completing assembly after analysis and optimization.The dynamic simulation software EDEM was used to establish the force model of the clamping and conveying mechanism,and the simulation analysis was conducted by simulating the cabbage conveying process to re optimize the structure.The modal analysis of the disc cutter using ANSYS shows that the rotational speed setting of 400 r/min effectively avoids the first six natural frequencies,verifying the rationality of the design.（3）Field trials.Trial production of a cabbage harvester and field operation tests were conducted to test its operational performance.Taking the root cutting qualification rate as an evaluation index,a three factor three level quadratic regression orthogonal test was designed,and response surface analysis was conducted to obtain the optimal parameter combination:cutter rotation speed 511r/min,entrainment rotation speed 154r/min,and machine forward speed 1.14km/h.Under this condition,the root cutting qualification rate was 99.64%.Based on the test results,the structural parameters of the harvesting components were improved and optimized.Compared with mechanized grain production,the mechanization level of cabbage production in China is very low.Currently,cabbage harvesting operations in China are basically completed manually,and there are almost no machines and tools available.The research on the above content will help promote the development of cabbage harvesting in China towards mechanization and automation.