INMATEH - Agricultural Engineering

9-18

Authors: Roberto FANIGLIULO, Renato GRILLI, Stefano BENIGNI, Laura FORNACIARI, Marcello BIOCCA, Daniele POCHI

The precision seed drills significantly improve the competitiveness of farms, in terms of sowing quality and yield. This paper refers to the field performance of the tractor-seed drill system and the seed spacing uniformity with reference to three precision drills with 4, 6 and 8 sowing units, respectively. The tests have been conducted using graded maize and sugar beet seeds, according to ISO 7256-1:1984 standard, under three speed conditions (5.0, 6.5 and 8.0 km h-1 ). The seed drills showed high values of the quality of feed index (>90%) even at the higher speed. The multiples index and the miss index were very low

31-40

Authors: Geng AIJUN, Gao ANG, Yong CHUNMING, Zhang ZHILONG, Zhang JI, Zheng JINLONG

In order to quickly and accurately identify the corn ears lost during the corn harvesting process, a corn ear loss detection method based on the improved Mask-RCNN model was proposed. The lost corn ears in the field were taken as research objects, the images of the lost corn ears were collected and the fallen ears data set was established. The size ratio of the Anchor Box of the area recommendation network was changed by changing the K-means algorithm to reduce the influence of artificial setting intervention. The group convolution was introduced into the residual unit and the channel dimension was divided into 3 equal parts to reduce the model parameters in the basic feature extraction network ResNet. A Convolutional Block Attention Module (CBAM) was introduced to improve the accuracy of the model in the last layer of the ResNet network. Results showed that the average target recognition accuracy of the method on the test set in this study was 94.3%, which was better than that of the previous model, and the average time to recognize a single image was 0.320 s. The proposed method could detect the lost corn ears during the harvesting process under the complicated background, and provide a reference for the corn ear loss detection of the corn harvester.

49-61

Authors: Weiwei WANG, Jiale SONG, Guoan ZHOU, Beituo PAN, Qingqing WANG, Liqing CHEN

Strip-tillage is an effective option for proper seedbed preparation because it ensures the suitable conditions for seed germination and has been widely implemented. This study developed a strip-tillage of corn planter row cleaner using bionic vertical rotary blades to remove seedbed straw and ideal soil for no tillage sowing can be created. Through the qualitative analysis of the serrated arrangement contour of the praying mantis foreleg tip, the characteristic curve of the praying mantis foreleg tip was extracted and fitted, and the bionic geometric structure surface of the vertical rotary blade was constructed. The model and interaction system were established in EDEM 2.6 simulation environment, and their physical properties were calibrated with the real properties of lime concretion black soil and wheat straw. According to theoretical design to set simulation parameters, the radius of the cutter head was set to 120 mm, the driving speed of the cutter shaft was set to 500 r/min, and the depth of the cutting edge was set to 10 mm, the operating velocity of the active anti-blocking device was set to 5 km/h. The experiment results show that when the moving speed ratio is increased from 2.8 to 4.5, compared with the traditional vertical rotary blades, the straw removal rate and soil uniformity of seed bed are increased by 6.4% and 9.3%, and the average torque of the rotary tiller has been reduced by 12.3% respectively, the process effect and sowing quality being effectively improved. The study can provide theoretical reference for realization of no-tillage sowing vertical rotary tillage blade to reduce resistance and consumption and improve the quality

73-80

Authors: Rong FAN, Qingling CUI, Qi LU, Huaming HOU, Decong ZHENG

Structural and motion parameters of screen surface have an important impact on the screening quality. In order to reduce the loss rate and impurity rate of buckwheat threshing material in the screening process and improve the screening performance of the vibrating screen, the planar square hole sieve, round hole sieve, non-planar convex-column sieve, pit sieve, and wave sieve were designed. Screening test was conducted on buckwheat threshing material under different screen structure based on the discrete element method (DEM). The results showed that the screening effect of convex-column sieve was the best, followed by pit sieve, and they were better than the traditional planar sieve. In single factor screening test of convex-column sieve, the ratio and height of convex column have significant influence on screening performance. Convex column rate, convex column height in a certain range were advantageous for screening. The results can lay a foundation for the determination of optimal parameter of screen structure and motion, and also provide a theoretical basis for the design of screening and cleaning equipment for buckwheat.

91-100

Authors: Peng WANG, Xiongwei LIU, Jianming JIAN, Jinyan TIAN, Renjie XING, Shulin HOU

To solve the problems such as low film recovery rate and high soil content of the recovered film of the surface residual film recycling machine, the parameters of the vegetable surface residue recycling machine were optimized. After modeling and theoretical analysis of the loosening shovel and film sweeping device, the key structural parameters of the machine were determined. The Box-Benhnken Design analysis test results in Design-Expert were used to establish the comprehensive effects of speed, rotational speed, and angle of membrane picking device on the recovery and soil content. Then Matlab was adopted to analyze the law of the comprehensive influence of three factors on two responses. The most significant factor affecting pickup net rate J was rotational speed Y2, and the most significant factor affecting soil percentage was the angle Y3 of the film picking device. By optimizing the experimental results by Design-Expert, the optimum operating parameters of the machine were obtained as follows: the forward speed of the machine was 3.2km/h, the revolving speed was 631.95r/min, the angle of the film picking device was 65.4°, the scavenging rate J and soil rate H of the residual film recycling machine were 87.084% and 10.382%, respectively.

111-120

Authors: Jiawei WANG, Xiaohong YU, Jianlong ZHANG, Decong ZHENG, Zhiwei LI, Haiyan SONG

Aiming at the problems of large loss rate and high damage rate during buckwheat threshing, an inner and outer roller buckwheat thresher was designed. The device is mainly composed of an inner roller and an outer roller, the inner roller is a rod-tooth combination roller, and the outer roller is a grid roller, the inner and outer rollers can be rotated independently. The outer roller is supported on the friction wheels and the supporting wheels, and driven to rotate by the friction wheel transmission system. The compression device is installed at the top to prevent the outer roller from slipping during the rotation. During working, the materials enter between the inner and outer rollers and the separation of grains and stems under the brushing and kneading action of the inner and outer rollers takes place. In order to push the materials between the inner and outer rollers smoothly, a double spiral blade type screw feeding device was designed. By establishing a mathematical model of material pushing, the screw feeding device has a material conveying speed of 1.87 m/s and a conveying capacity of 4.29 kg/s. In order to study the threshing performance, the threshing device was installed on the basis of the Kubota 688 tracked type combine to complete a prototype of a tracked buckwheat combination harvester. Field tests show that the grain impurity rate is 6.50%, the grain damage rate is 1.42%, the threshing loss rate is 0.25%, the cleaning loss rate is 1.01%, the direct loss rate of the header is 2.43%, and the total machine harvest loss rate is 3.69% at the working speed of 0.53 m/s and the feeding rate of 0.41 kg/s. The test results provide a basis for the improvement of buckwheat mechanized harvesting machinery.

128-138

Authors: Jianguo YAN, Lijuan WANG, Shengshi XIE, Chunguang WANG

To study the interaction between the tractor and the field terrain on which the tractor operates, the characteristics of tractor vibrations excited by the measured profiles were analyzed by simulations and experiments. The results show that the theoretically calculated values of the tractor vibrations excited by the field road profiles, including the natural frequencies of the tractor’s center of gravity, acceleration RMS values of the tractor axles, and the wheel dynamic loads, were close to the measured values, with an error range of 3.5% to 10.9%. Considering the filtering effect of large tractor tires on the measured road profiles, these errors are within an acceptable range. The results confirm the validity of the methodology presented in this paper for investigating the tractor vibrations caused by measured profiles as excitations.

150-158

Authors: Xiaohui LEI, Jin ZENG, Yannan QI, Tao XYU, Andreas HERBST, Xiaolan LYU

To solve the problem of mechanized weeding in trunk type pear orchard, combined with the technology of stubble elimination and hydraulic obstacle avoidance, the authors designed an obstacle avoidance compound mower. This paper carried out a field performance evaluation test to verify its usefulness. Six indexes were tested to evaluate its working performance. The results were: inter-row crushing rate of 89.99%, intra-row miss cutting rate of 2.42%, stubble stability coefficient variation of 4.25%, working efficiency of 0.32 hm²/h, fuel consumption of 16.25 L/hm², profitable area of 0.75 hm². The study could provide a reference for orchard mechanized weeding.

167-181

Authors: Shufeng LIU, Hanxiang WANG, Zhaoqin LV, Jingwei SUN, Xinpeng SHI, Jinxing WANG

Organic fertilizer applicator currently has poor versatility toward different properties. A solid-liquid mixed fertilizer device is designed based on the numerical simulation method of solid-liquid two-phase flow. Based on the parameters analysis and viscosity measurement of different organic fertilizer particles, the ribbon-screw type agitator was selected as the basic structure. Using Box-Behnken, three test factors including agitator speed, the mixture ratio of fertilizer and water, agitator height were determined, the agitator was optimized with the test evaluation indexes, the density variation coefficient, and agitator shaft power on 10 mixing planes in the agitator. The result showed that the rotating speed was 80 r/min, the mixing ratio of fertilizer and water was 1.2, and the agitator height was 700 mm, the working parameter combination is optimal. A coarse particle solid-liquid two-phase flow model of the fertilizer discharge pump was established, to obtain the external characteristic curve of the fertilizer pump and analyse the influence of different mixing ratios of fertilizer and rotation speed on the fertilizer pump. In order to prevent the separation of fertilizer and water and achieve better effect, 1140 r/min was comprehensively determined as the working speed of the fertilizer pump. The strength of the agitator meets the working requirements. The solid-liquid deep fertilizer device text bench for organic fertilizer was set up under the optimal working parameters, the result shows that the research results can provide a reference for the design of organic fertilizer solid-liquid mixing fertilizer applicator.

191-200

Authors: Hongbo ZHAO, Zhiqi ZHENG, Weiguo ZHANG, Zhengdao LIU, Wenzheng LIU, Yuxiang HUANG

Anti-blocking and seedbed cleaning are one of the key process in no/minimum till seeding in the Northwest arid area in China. Soil tillage performance and straw cutting performance such as tillage depth stability, straw cutting ratio, torque requirement are important indexes that influence anti-blocking and seedbed cleaning performance. In order to investigate the performance of rotation type anti-blocking device of no/minimum till seeder under different operation parameters, this paper designed a rotation type anti-blocking device test bench. It mainly comprises frame, torque sensor, speed sensor, speed-adjustable motor, straw fixture, rotation blades and land wheel, its working width was 1100 mm. The torque requirement could be determined with torque sensor and rotation speed could be determined with proximity speed sensor. The test bench could hitch with test vehicle of soil bin to conduct experiment. With the test vehicle, travel speed could be adjusted; with the speed adjustable motor, rotation speed (0-300 r/min) could be adjusted; besides, operation performance of different rotation type device can be determined by changing the device. Soil bin experiment of idling test, tillage test and straw cutting performance test was conducted taking rotation speed as testing factors and torque and straw cutting performance as response indicators. Results showed that tillage depth stability of the test bench was 87.2%, and it could satisfy the test requirement and operation steadily. Results of the tillage experiment showed that torque requirement of tillage and idling test both increased with the increase rotation speed significantly; results of the straw cutting test preliminarily found that the critical cutting speed under supported cutting was between 100-200 r/min under the given condition. This study could provide reference for the performance research for anti-blocking device of no/minimum till seeder.

211-218

Authors: Iuliana GAGEANU, Dan CUJBESCU, Catalin PERSU, Gabriel GHEORGHE

The paper presents the experimental validation of two mathematical models describing biomass powders compaction (a model that expresses the final density of pellets as determined by the final pressure applied during the process, the initial material moisture and the initial density of the material, but also a mathematical model obtained through dimensional analysis, using Π theorem, which expresses the density of pellets as determined by pressure, heat, the initial density of the material, the pelleting speed of and the initial volume of the material), through experimental researches using a ring die pelleting equipment. The results showed a strong correlation between the data estimated theoretically and the experimental data, but also a strong influence of biomass material initial moisture on the density of the pellets obtained.

229-238

Authors: JiaXi ZHANG, JinMing LI, YiChao WANG, MaoBo WANG, Peng ZHANG, ZhaoSen DONG, YunLong MA

In order to address the problems of low efficiency and low degree of mechanization of artificial soil clearing of the grapevines in spring in Xinjiang grape growing regions, a grapevine cold-proof soil clearing machine was designed. The machine is mainly composed of a frame, gearbox, suspension device, soil clearing parts, hydraulic system and mechanical transmission system, etc. The motion track of the soil clearing parts was analyzed to obtain the key factors affecting the performance of the grapevine cold-proof soil clearing machine that were determined. The three-factor, three-level quadratic regression orthogonal experiment was carried out with the forward speed, soil clearing parts’ diameter and rotation rate of soil clearing parts as factors and the soil clearing distance was used as evaluation index. The results showed that the order of influence on the soil clearing distance was rotation rate of soil clearing parts > forward speed> soil clearing parts diameter. The parameters were optimized based on response surface method with the following results: the rotation rate of soil clearing parts speed was 277.7 r/min, the forward speed was 3.5 km/h, and the soil clearing parts diameter was 681.7 mm. The validation experiment was carried out with the optimal parameters’ combination. The soil clearing distance was 85.44 cm, which was consistent with the predicted results of the model. This research results can provide reference for the development of other types of grapevine soil clearing machine.

247-256

Authors: Min LIU, Zhanfeng HOU, Xuejie MA, Xiwen ZHANG, Nianzu DAI

The calibration of the powder simulation parameters could improve the accuracy of the pelletizing and coating simulation process. In this paper, we take coated powder (after this referred to as powder) as the research object, based on particle amplification theory, combined with physical tests to calibrate the contact parameters of powder and seeds (after this referred to as seeds), conduct the angle of repose simulation tests of powder, carry out Plackett-Burman test, steepest climb test, and Box-Behnken test in turn, and establish quadratic regression equation to obtain the best combination of powder simulation parameters. The difference between the contact parameter combinations obtained from the simulation tests and the physical test results is less than 1%, providing some reference for calibrating similar powder material parameters.

267-278

Authors: Ruyi ZHANG, Zongwei JIA, Ruibin WANG, Simin YAO, Ju ZHANG

The acquisition of traditional wheat ear phenotypic parameters is labour intensive and subjective, and some trait parameters are difficult to measure, which greatly limits the progress of wheat ear research. To obtain the phenotypic parameters of wheat ears in batches at a low cost, this paper proposed a convenient and accurate method for extracting phenotypic parameters of wheat ears. First, three improvement directions were proposed based on the Mask-RCNN model. 1) To extract the multiscale features of wheat ears, a hierarchical residual link was constructed in a single residual block of the backbone network ResNet101 to obtain information on different sizes of receptive fields. 2) The FPN was improved to increase the recognition accuracy of wheat ear edges through multiple two-way information flow sampling. 3) The mask evaluation mechanism was improved, specific network blocks were used to learn and predict the quality of the mask, and the detection of wheat ears and grains was performed by precise segmentation; an automatic extraction algorithm was designed for wheat ear phenotypic parameters based on the segmentation results to extract 22 phenotypic parameters. The experiments showed that the improved Mask-RCNN was superior to the existing model in the segmentation accuracy of wheat ears and grains; the parameters of wheat ear length, width, and number of grains extracted by the automatic extraction algorithm were close to the manual measurement values. This research meets the demand for automatic extraction of wheat ear phenotype data for large-scale quality testing and commercial breeding and has strong practicability.

289-300

Authors: Qi LU, Decong ZHENG, Lihong LI, Yun LIU

A 5tg-85 buckwheat thresher was designed to solve the problems of low mechanical harvesting level of buckwheat in hilly and mountainous areas, high work intensity of threshing and grain cleaning, and few available machines and tools. The machine adopts rasp bar-nail tooth combined threshing device and air screen cleaning device, which can complete threshing and grain cleaning at one time. In the paper, the structure, transmission system and key components of the thresher were designed, the parameters were calculated, and the threshing performance test was carried out. The results show that when the moisture content of buckwheat stem is 75%, the moisture content of grain is 17%, and the grass grain ratio is 4.4, when the rotating speed of the threshing drum of the thresher is 500r/min, the threshing gap is 10mm, the feeding amount is 0.8kg/s, the air speed of suction mouth is 8m/s, and the vibration frequency of vibrating screen is 25.12 rad·s-1. The crushing rate Zp is 1.13%, the impurity content Zz is 2.73%, the unthreshed loss rate Sw is 0.07%, the entrainment loss rate Sj is 1.77%, the cleaning loss rate Sq is 1.96%, the spatter loss rate Sf is 0.62% and the total loss rate S is 4.42%. The threshing effect is good, which meets the requirements of buckwheat threshing. The development of this machine will reduce the manual cost of buckwheat threshing, improve the work efficiency, improve the mechanized harvest level of buckwheat, and promote the development of buckwheat industry.

311-320

Authors: Liquan TIAN, Zhao DING, Zhan SU, Lizhen LI, Zhiming WANG

In order to realize the mechanical direct seeding of precision rows and hills in rice field, a rotary precision hill direct seed-metering device for rice was designed. Through designing the key components of seed-metering device and analyzing its working principle, the main factors and critical conditions affecting the seed-metering performance were obtained. Using the secondary rotation combination test, taking the rotation speed of seed-metering disc and seed capacity height as the test factors, and the re-broadcasting rate, seed-metering qualified rate and miss-seeding rate as the indexes, the seed-metering performance was experimentally studied by using the JPS-12 seed-metering device tested. Design-Expert 6 0.10 software was used to analyze the test data to obtain the mathematical model between factors and indexes. The test results show that when the speed of the seed-metering plate was 24.60r/min and the seed capacity height was the radius of the seed-metering disc, the qualified rate of seed-metering was 94.83%, the re-broadcasting rate was 3.43%, and the miss-seeding rate was 1.74%. The seeding performance meets the agronomic requirements of rice seeding, and provides a reference for the design of the whole machine.

331-339

Authors: Olena ZOLOTOVSKA, Mykola KHARYTONOV, Iryna RULA, Nadia MARTYNOVA, Hynek ROUBÍK

The final composition of volatile components in the process of oxidative pyrolysis depends on the temperature level of the process. The gas output increases with the growth of hydrogen, methane and heavy hydrocarbons concentration in the process of pyrolysis in the range of 200-500°C. In this case, there is a noticeable decrease in undesirable impurities in the output of carbon dioxide and nitrogen in the fuel gas. The obtained data on the dynamics of thermal decomposition of biomass under heating conditions reflect the complex dependence of the yield of total gas individual components both on time and on the temperature of the process. The more volatiles contained in the source fuel, (the other things being equal) the faster the gas mixture ignites, and the more intensely it burns out. The composition and temperature of the gas mixture affects the pressure drop and auto-ignition temperature in the pyrolysis chamber. It was found that the lowest self-ignition temperature of a gas mixture is 490°C. A series of experiments to determine the critical condition for self-ignition at a constant temperature of 490°C and various initial pressures of the mixture (100-300 kPa) was carried out. It was found that the transition from a smooth increase in pressure of 90 kPa to an explosive one (up to 300-400 kPa) depends on the composition and temperature of the gas mixture. Therefore, the composition of the gas and its ignition temperature can be controlled by adjusting the mode of pressure increase in the reactor.

351-360

Authors: L.M. ZHOU, K. NIU, K.K. CHEN, Y.W. YUAN, B. XUE, L.L. WANG

Precision fertilization is one of the important links in the precision agricultural operation system. In recent years, the demand for precision fertilization in facility greenhouse has become more and more urgent. As such, this paper designs an accurate and practical fertilization on-line monitoring system. The system adopts capacitance conversion chip PCAP01 and SCM STM32F103C8T6 to build a capacitance detection circuit. The effective acquisition of differential capacitance sensor microcapacitor signal output under this system is realized. The response relationship between the mass flow and the sensor capacitance output was studied, and a linear fitting model of fertilization was established. According to the prediction, the model determination coefficient was 0.9997. The experiment shows that the system has good adaptability to ambient temperature. The average measurement error is 1.13%, which meets the technical requirements of flow measurement. The capacitive fertilization online measurement system provides an effective way for the on-line acquisition of fertilization flow. It is of great significance for the implementation of high-precision variable fertilization.

373-382

Authors: Yanqing ZHANG, Qingliang CUI, Shaobo YE, Can WANG, Zhiyong ZHANG

Fluid seeding is a new technology for drought resistance, water saving and yield increase in modern agriculture. To improve the uniformity of fluid seed metering of millet, the mechanical stirring device was added to the metering device, and the single-factor tests were carried out on the size parameters of the pump tube, the installation position and the parameters of mechanical stirring. The stirring speed, the ratio between the length of stirring paddle and the diameter of seed box and distance between the pump tube and the stirring paddle were selected as independent variables, and the right rate of hill distance, right rate of seeds per hill and rate of no seed hill were selected as response values. According to the test design principle of Central Composite Design, a response surface analysis method was used to establish mathematical models between each experimental factor and performance index, and the influencing factors of fluid seed metering were analyzed. The single-factor test results showed that when the pump tube was installed on the side of the seed box, and its inner diameter and wall thickness were 4.8 mm and 1.6 mm, respectively, the seeding performance was better. The response surface test results showed that the selected factors all have an influence on the performance of millet fluid seed metering, and the optimal stirring parameters were the stirring speed of 30 r/s, the ratio between the length of stirring paddle and the diameter of seed box of 0.69, and distance between the pump tube and the stirring paddle of 0.11 cm. The verification test was conducted under these parameters, and the right rate of hill distance, right rate of seeds per hill and rate of no seed hill were 94.14%, 84.24%, and 2.21%, respectively, and the error from the predicted values was less than 4%. The performance indexes of fluid seed metering were improved compared with the fluid seed metering device without stirring device, indicating that the optimized stirring parameters can improve the performance indexes of millet fluid seed metering. This study can provide a reference for the research and development of key technologies and equipment for precision fluid seed metering of millet.

393-402

Authors: Danyang LV, Jiayi REN, Meng ZHANG, Xiangyou WANG, Pengxiang MENG, Xueqiang LI, Xiaohui YANG

Because of the low impurity removal rate and high damage rate of the potato combine harvester during the working process, a new type of impurity removal device for the potato combine harvester was designed. The device was mainly composed of retaining plates, impurity removal rollers, smooth rollers, and a control system. To determine the best working parameters of the device, the rotational speed of the rollers, the distance between two rollers, and the inclination angle of the device were used as the test factors. The impurity removal rate and damage rate were employed as the evaluation indexes. Then, the single factor test and the second rotation orthogonal regression test were performed. The optimum combination after parameter optimization was determined to be as follows: rotational speed of the rollers was 113.4r/min, the distance between the two rollers was 97.5mm and the inclination angle of the device was 10.4°. The corresponding impurity removal rate was 95.12%, and the damage rate was 0.54%. The device can better meet the requirements of impurity removal operations.