Development And Experiment Of The Centralized Rapeseed Fowing And Fertilization Device

Oilseed rape is one of the most important oil crops in China,and its by-product seed meal is also the second largest source of high-quality forage protein in China.The hilly mountainous area is the main area for rape cultivation in China,and rape in this area is mostly planted in hilly mountainous areas with scattered soil,small area and large slope,so the mechanization level of rape cultivation is low.At present,rapeseed planting in hilly mountainous areas mainly adopts the traditional manual sowing method,but this method has problems such as high labor intensity,low utilization rate of seed and fertilizer,and difficulty in large-scale production.Considering the geographical characteristics of hilly mountainous areas,it is difficult to apply the existing rape seeding and fertilizing device,so it is particularly important to develop a rape seeding and fertilizing device applicable to this area.In this paper,according to the requirements of oilseed rape cultivation in hilly mountainous areas,a set-row type oilseed rape sowing and fertilizing device with light and simplified hole sowing is developed for the above problems.The main research contents are as follows:（1）Research on the physical and mechanical characteristics of rape seeds and fertilizer particlesResearch on physical and mechanical characteristics of rape seeds and fertilizer granules.The parameters of seed sowing and fertilizing device were measured to provide a basis for the design and analysis of the structural parameters of the key components of the sowing and fertilizing device and to provide data support for the simulation analysis.（2）Structure design of set-row rape sowing and fertilizing deviceAccording to the agronomic requirements of rape planting in hilly mountainous areas,the overall scheme of the set-row rape seeding and fertilizer application device was proposed,which adopts the combination of mechanized hole sowing with one tool and four rows,pneumatic set-row rape seeder and variable set-row hole fertilizer dispenser,and determines the overall scheme design route.The main factors affecting the performance of the device in actual operation were determined,and the design analysis of the key components,such as the negative pressure roller（size of the roller,shape of the type hole,number of type holes,etc.）and the fertilizer distribution fan（shape of the distribution fan,size of the fertilizer compartment,etc.）,was completed;3D modeling,simulation assembly and motion simulation of the structural components of the device were carried out using Creo 6.0.（3）Simulation analysis of set-row rape seeding and fertilizing deviceThe working process and effect of rapeseed seed and fertilizer plant were simulated,the movement of seed and fertilizer in the actual operation process,and the structure parameters of key components were optimized by CCD central combination test design method,and analyzed by response surface analysis.The results are:when the operating plant distance is 200 mm,the forward speed of the sowing and fertilization device is 0.4m/s,that is,the drum rotation speed is 10 r/min,the speed of the fertilizer fan is 15r/min,the diameter of the hole is 1.3mm,and the negative pressure of the drum is 1816Pa.Under this condition,the qualified rate of hole count is 91.308%,and the desirability of simulation is 96.1%;blade tilt angle a₃is 48,and blade tilt angle a₄is 38.Under this condition,the error was 8.109%and 6.615%,and the desirability of simulation is 97.4%.（4）Design of control system for set-row rape seeding and fertilizer application deviceThe design of the control system was carried out.In terms of hardware,the selection of core controller（PLC）,actuator,sensor and other hardware is completed and the hardware system is built.In terms of motion control,the fuzzy PID control algorithm is selected to control the brushless motor module of the negative pressure fan and the simulation is verified in MATLAB/Simulink,and the results show that the fuzzy PID control algorithm has no overshoot and the adjustment time is 0.298 s,compared with the traditional PID overshoot of 11.95%and regulation time of 0.399 s,which has better control performance;in terms of software,the main control program and touch screen human-machine interface were designed using GX Works2 and SK Workshop software,respectively.（5）Performance test of set-row rape seeding and fertilizing deviceAfter the completion of the structure design and control system construction of the rapeseed sowing and fertilizing device,the prototype trial production was carried out,and the performance tests were carried out respectively on the seed arrangement performance of the pneumatic seed arrangement device and the variable seed arrangement device by means of the combination of the conveyor belt platform,the static platform of the hole fertilizer discharge and the field machine multi-performance test platform.The results show that the average pass rate of the number of holes in each row ranges from 86 to 90%,and the average of the four rows is 87%.The relative error with the predicted value is 4.31%.The drainage quantity error of each row was11.32～12.38%,and the mean value of the drainage quantity error of the four rows was11.84%,which was 3.83%relative to the predicted value.The conveyor belt hole spacing error of each row ranges from 10.23 to 12.73%.The average conveyor belt hole spacing error of four rows is 11.39%,and the relative error with the predicted value is4.77%.The field experiment hole spacing error of each row ranges from 12.78 to14.41%,and the average hole spacing error of four rows of conveyor belt is 13.54%,which is 6.92%compared with the predicted value of simulation,which verifies the effectiveness of simulation and shows that the device has good practical performance.