Research And Design Of Electric Drive Soybean Plot Seeder Based On Automatic Seeding System

Soybean has become one of the main grain crops in China as domestic economy development.It is necessary to develop the whole process mechanized agricultural equipment aimed to soybean production.As the breeding machinery equipment developed by academic institutions,soybean plot seeder is one of the most important parts of the whole soybean industry chain.The main factor affecting seeding quality is how to control soybean seeding device accurately.On the other hand,the research and design of automatic supplying,seeding,and cleaning device are the key section to achieve seeding automatically.Automatic seed-supplying devices were only applied to the centrifugal type and the cartridge-clip type of drill seeders.Besides,artificial assistance was necessary for its operation.There was no application of the seed-supplying equipment for precision seeders.Automatic seed-cleaning devices were only applied for the research and application of the air-suction seeding device.There was no application of the seeding-cleaning equipment for precision seeders.It is essential to augment the research of automatic seed-supplying,seeding and seed-cleaning system of the soybean plot seeder.In this paper,in order to improve and solve the above deficiencies and questions,a new electrical type soybean plot seeder was designed to achieve supplying,seeding and cleaning automatically based on the soybean seeding agricultural requirements.Through the types and features analysis of the existing plot seeders,a new scheme was proposed and demonstrated.The design scheme and the control pattern of the main system and device were determined.The entity model of the whole soybean plot seeder was designed and engineering drawings were drawn.The prototype was manufactured and the laboratory and field tests were carried out.The main contents of this paper as follows:1.The theory of planetary wheel revolving gear train is quoted,and it is applied to the scheme design of automatic seeding device for soybean planter.The method of accurate seeding of rotating seed cup is established,and the scheme of automatic seeding device for turntable soybean planter is developed.To solve the problem that the existing plant seeder does not have an automatic feeding device.A new type of seed cup and supplying plate were designed and its structural parameters were determined.The automatic seed-supplying system was analyzed by dynamics and the movement characteristics of each outfit were researched.Programs of the systematic control method were designed so that the system can control the working time of the seed-supplying devices accurately and achieve seed supplying automatically.Through the test and analysis of the working performance of the seed-supplying device,the device can complete 12 plots seed supplying continuously at a time,which is stable,reliable and reduces the labor intensity.2.Based on the genetic algorithm to fuzzy control the speed of the seeding machine,the control method of matching the speed of the seeding motor and the seeder is found.The mathematical model was established,the design of the automatic seeding system is completed,and the invention solves the problem that the control precision of the existing seeding system is low.The seeding wheel of socket seeding device was analyzed by dynamics and simulation tests.Mathematical model aimed at the seeding control method was established.Response surface analysis was carried out among factors such as soybean quality,seeder speed and the rotation speed of the seeding shaft,etc.The optimal combination was obtained and the automatic seeding system was designed.Through the test and analysis of field experiment,it could be verified that the leaky index,the replay index and the spacing coefficient of variation meet the operation standards of the plot seeder.3.A negative pressure cleaning scheme was established,and the minimum starting speed and minimum suction wind speed of soybean were found.The narrow tube effect theory was applied,and the narrow tube clearing port was designed.The design of the soybean automatic cleaning device was completed and the mechanical type was solved.Breeding problem of residual soybeans in the seed meter.The mechanism of the cleaning-seed system was analyzed.Especially,The cleaning-seed process of soybean was analyzed by dynamics and gained related parameters about soybean properties.The latest designed cleaning outlet was analyzed by flow field analysis.Through the test and analysis of the working performance of the seed-cleaning device,the system can clear remained seed rapidly and completely,improve the working efficiency.4.The method of adjusting the ditching depth by using the push rod motor solves the problem that the existing mechanical opener needs to manually adjust the sowing depth.The motor driven trenching system was designed and the mechanical analysis of the trenching device was carried out.Through the performance tests,the ditching system effect was great,its average seeding depth and seeding depth qualified rate meet the requirements of the plot seeder standards.5.A new pure-electrical power system is designed by adopting battery-motor power scheme.The main device and parameters of the motor driving system were analyzed and calculated.Through the field tests,the electrical plot seeder continuous operation time after once charge could meet the expected design goals and satisfy the normal operation requirements.6.The modular design of the whole machine control system is applied,and the control program of a key system is modularized to improve the applicability of the control system.7.The laboratory and field tests of the soybean plot seeder prototype were carried out.The laboratory tests showed that the qualified rate of seed cup offset kept between 99.4%?99.6%,the qualified rate of perfect seed supplying kept between 99.738%?99.836%.Meanwhile,the leaky index kept between 0.15 %?1.90 %,the replay index kept between 0.85 %?2.00 %,and the spacing coefficient of variation kept between 0.30 %?7.00 %.The field tests showed that: The automatic seeding system of the planter can complete the seed supply work of the corresponding cell within a set period of time,the seed cup is basically no offset,the seed is basically not broken,and the automatic seeding work of 12 cells can be completed continuously.Each row average of leaky index kept between 0.11%?0.25%,the average of replay index kept between 0.88%?0.96%,and the average of spacing coefficient of variation kept between 0.253%?1.047%.It could be verified that the automatic seed-supplying,seeding,seed-cleaning system and the whole control system meet the operation standards of the plot seeder,and the performance was steady.