Analysis of the metering performance for typical shape maize seeds using DEM

The irregular shape,varying internal compositions,and uneven distributions of maize seeds can degrade the metering performance of maize seeders.This study investigates the effect of irregular maize on the performance of a high-filling-rate seed metering device using DEM.The results show that the seed population in the seed box formed large and small cycles of seed transport due to the disturbances caused by the three wheels.The increasing angular speed of the three wheels reduced the rate of seed filling in the seed filling regions by gravity and disturbances.In addition,an analysis of the repose angle formed by the dropped seed indicated that the angular speed of the taking seed wheel has a certain effect.The large angular speed reduced the coefficient of variation of the seed drop location.The repose angle of the horse tooth seed was greater than those of the other.Meanwhile,the irregular maize seed can also reduce the coefficient of variation of the seed drop location.A comparison between the simulation and experiment results indicates the number of metering seed were basically the same.

Design and experiment of seeding performance monitoring system for suction corn planter

To realize the highly precise and real-time monitoring of seeding performance in suction-type corn planter,and intelligent detection technology was presented.In this monitoring system,firstly,the sensor was designed based on the photoelectric technology.Meanwhile,in order to reduce the influence of dust in the field on the photoelectric sensor,the installation position of the sensor was changed to the space under the seed plate instead of the traditional position,that is,the middle of the seed tube.Secondly,the scattering angle of the highlighting light-emitting diodes was considered to calculate the spacing of transmitters to realize non-blind area detection.Last but not least,the peak-detection algorithm was utilized to increase the detection accuracy.Therefore,after a lot of the indoor and field experiments,the analysis shows that the detection accuracy of seeding quantity can reach 98.45%,alarm delay time under abnormal circumstances is not more than 2 s.Obviously,this system can meet the requirements of seeding completely and improve its reliability greatly.

Seeding performance of air-assisted centralized seed-metering device for rapeseed

In order to analyze seed movement characteristics and improve seeding quality of air-assisted centralized metering device for rapeseed,the effects of the model-hole structure on seed feeding performance were investigated using EDEM simulation.Furthermore,the CFD-DEM coupling approach was applied to determine movement trajectories and airflow fields.The impacts of rapeseed varieties and rotational speed on seeding performance were investigated by bench tests.The results showed that the seed feeding quantity increased with the increase of model-hole’s length,depth and section size.Under the model-hole’s depth of 3.0 mm,the type II model-hole and model-hole’s length of 10 mm,both the variation coefficient of seed feeding quantity and hill diameter were lower which meet the seeding quantity requirement of 2 seeds in each hill.It was revealed that the seed population migrated in a large airflow velocity area and the distribution was uniform.The bench tests indicated that rapeseed varieties and rotational speed had a significant effect on the seed feeding quantity in each hill at rotational speed of 10-40 r/min.The variation coefficient of seed feeding quantity in each hill was less than 17.0%for each treatment.The hill diameter,which did not exceed 3.5 cm,tended to reduce with increasing rotational speed.The variation coefficient of seeding quantity in each row and seeding uniformity was less than 6.5%and 32.0%,respectively.Field experiments demonstrated that the seedling was 9-13 plants per meter each row for three rapeseed varieties.The variation coefficient of plants was less than 25.0%for six rows and their yields reached 2761 kg/hm2,which realized the mechanized planting requirements.The results can optimize structure of an air-assisted centralized metering system and improve seeding performance.

Optimization of operating parameters of seeding device in plot drill with seeding control system

Plot drill has a significant impact on field breeding by replacing manual seeding.However,the seeding performance of plot drill needs to be further improved as the mechanical transmission method cannot work under the optimal combination of operating parameters.In this study,a cone compartment tray of sowing device was evaluated under the laboratory conditions,using a self-designed seeding control system to adjust the operating parameters.Among them,a plot seeding control system was involved that could set operating parameters through an Android terminal,which effectively reduced the difficulty of parameters adjustment.The method of central composite experiment design was employed to conduct experiments and explore the effects of experiment factors such as lifting height of storage tube(LHST),rotation speed of cone compartment tray(RSCCT),and rotation speed seed distributor(RSSD)on the seeding uniformity coefficient of variation among rows(SUCVR)and the rate of damaged seeds(RDS).For SUCVR of wheat,the results showed that the importance order of main factors from high to low was RSSD,RSCCT and LHST.And for SUCVR of buckwheat,RSCCT had the largest influence,followed by RSSD,and LHST had the smallest influence.For RDS of wheat and buckwheat,only RSSD had a very significant effect among the main factors.The experiments data of wheat indicated that when operated at 27.2 mm for LHST,4.5 r/min for RSCCT and 1169 r/min for RSSD,the sowing performance of wheat was optimal,with SUCVR and RDS values of 5.02%and 0.117%,respectively.The buckwheat seeding performance was found to be optimal when the LHST,RSCCT and RSSD were 26.5 mm,3.9 r/min and 711 r/min,and SUCVR and RDS were 4.74%and 0.113%.The seeding control system realized the electromechanical control of the seeding equipment,was convenient for parameter setting and stepless adjustment,and could be operated under an optimized combination of operating parameters.The research results could provide a reference for the performance improvement and application of plot drill.