Precision Seed Metering Device Research Articles

The influence of a seeding plate of the air-suction minituber precision seed-metering device on seeding quality

The influence of a seeding plate of the air-suction minituber precision seed-metering device on seeding quality

Study on the excess seeds removing performance of a potato precision seed metering device

In the potato mechanical planting industry, the high multi-seeding rate and miss-seeding rate are problems that exist in many potato precision seed metering devices. The main potato seeds in China are cut potatoes with different shapes and sizes. However, there is a lack of research on precision seeding technology for cut potatoes, and the adaptability of many existing potato seeding devices on cut potato is poor. The mechanized precision seeding of potato can effectively reduce labor consumption, improve the seeding effect (decrease multi-seeding rate and miss-seeding rate), improve the improve production of potato per acre and improve the quality commodity potatoes. In response to the above issues, a precision seed metering device with novel scoops, which can adapt to various sizes and shapes of cut potatoes, was developed. In this study, the different seed collecting scenarios (SCSs) were constructed. Through the statics and kinematic analysis, the excess seeds removing (ESR) process was divided in to three areas. The kinematic model of seed potato was established to study the influence of different SCSs and sprocket rotational speeds on the ESR performance, and preliminary determined the appropriate sprocket rotational speed range for ESR process. Then, the coupled simulation results of EDEM and RecurDyn revealed that different sprocket speeds and SCSs had a significant influence on the ESR performance. Finally, the bench tests and field tests were conducted to verify the actual performance of the precision seed metering device. The results showed that, with the increase of the sprocket rotational speed, the ESR performance of the device improved, the multi-seeding rate significantly decreased, but the miss-seeding rate increased. High sprocket rotational speed will remove more seed potatoes and cause high miss-seeding rate. The bench tests showed the appropriate sprocket rotational speed for medium and large potato was 35 r/ min. The field tests obtained the best qualified-seeding rate of 91.54%, the miss-seeding rate of 3.08% and the multi-seeding rate of 5.38%. This study can provide theoretical reference for the design of potato precision seed metering device.

气压式玉米精量排种器递进性清种装置设计与试验

In order to improve the sowing performance of air-pressure maize dense planting high-speed precision seed-metering device and reduce the occurrence of multiple and missed seeds phenomenon, a seed-cleaning mechanism with progressive seed scraper was designed. The structure and working principle of the seed-metering device and seed-cleaning mechanism are described, the mechanical model before and after the excess seed enters the seed cleaning area is established, and the design parameters of the key components of the seed-cleaning mechanism are determined through the method of theoretical analysis. The experiments of single-factor and multi-factor are conducted with seed clearing angle, operating speed, positive pressure value of blower as influencing factors, and with qualified index, miss index, multiple index as the experimental indexes. The results show that the optimal seed-clearing performance parameter combination of the seed-cleaning mechanism is seed-clearing angle of 0.024°, operating speed of 10 km/h, positive pressure value of 6.0 kPa, verification test of the parameter combination of the qualified index of 98.11%, multiple index of 1.44%, miss index of 0.45%. In the comparative experiment, the qualified index of the device with seed-cleaning mechanism increased by about 2.3% compared to the device without seed-cleaning mechanism, and the multiple index decreased by about 2.2%. The seed-cleaning mechanism is reasonably designed to meet the seed clearing operation requirements of air-pressure maize dense planting high-speed precision seed-metering device.

玉米内充气压式高速精量排种器推种轮设计与试验

In order to improve the uniformity and stability of seed delivery and meet the requirements of precision sowing operation, a kind of seed push wheel designed to mesh with the seed discharging disk was developed. The wheel underwent theoretical analysis and experimental optimization regarding parameters such as tooth profile, tooth count, and tooth height. Using a pneumatically inflated maize precision seed-metering device as the seeding carrier, a full-factorial experiment was conducted with operational speed and tooth height as the experimental variables, and qualification rate, reseeding rate, and leakage rate as the performance indicators. A multivariate quadratic regression model was established to assess the relationships between the factors and indicators. The results indicated that optimal seed guiding performance was achieved when the seed push wheel had 9 teeth, a tooth height of 5.2–6.2 mm, and an operational speed of 9.0–12.6 km/h. This study provides a theoretical foundation and data support for the development of precision seeding technology and corresponding seed guiding devices.

基于EDEM软件的气压式精量排种器充种性能模拟与试验

In order to study the effect of population disturbance on the filling performance of the seed metering device, this paper uses the pneumatic precision seed metering device as the model, and uses EDEM software to simulate the population movement of three different seed metering devices. The bench test was carried out at different pressures at 12 km/h and at different speeds at 3.5 kPa. The results show that the designed seed disk with grooves has the most intense disturbance and the highest qualified rate. In order to verify the performance of the disk, full factor tests are carried out on the air pressure and speed, The test results show that when the operating speed is 10~12 km/h and the positive pressure is 3~3.5 kPa, the leakage rate is no higher than 5.42%, the replay rate is no higher than 0.42%, and the qualified rate is no lower than 94.58%. When the operating speed is 14 ~ 16 km/h and the positive pressure is 3.5~4 kPa, the leakage rate is not higher than 6.7%, the replay rate is not higher than 1.04%, and the pass rate is not lower than 93.12%. All the indicators are better than the national standard.

Design and Experiment of Precision Seed Metering Device for Flow Adsorption of Quinoa Seeds

This paper proposes a solution to the problem of tight population in the filling area of traditional air suction seed metering devices during quinoa sowing, which leads to inaccurate adsorption. The proposed method disperses the population into a stable seed flow and absorbs the seeds in a flow posture. The flow adsorption precision seed metering device is designed and improved, and the key structure parameters are optimized based on the shape and size parameters of quinoa seeds. A four-factor and three-level response surface orthogonal test is conducted using the Box–Behnken experimental design. The number of seeds, flow angle, negative pressure at the suction hole, and advancing speed are taken as experimental factors, and the qualified index of grain number per hole, qualified index of hole distance, and coefficient of variation of hole distance are used as evaluation indices. The results are optimized using extreme value theory, and it is found that when the seed amount is 5.82 mm, the flow angle is 31.08°, the negative pressure of the air chamber is 1.7 kPa, and the advancing speed is 3.82 km·h−1, and the qualified index of hole number is 94.37%, the qualified index of hole distance is 95.39%, and the coefficient of variation of hole distance is 4.51%. The results are in general agreement with the prediction through the bench validation test, which meets the requirements of quinoa seed metering devices.

Development of a novel perforated type precision metering device for efficient and cleaner production of maize

This research presents a filling method that strips the kernels from the seed group to address the poor performance and energy efficiency of the mechanical maize metering devices at high-speed operating conditions. In addition, it advances the design of a novel perforated type precision seed-metering device. The quantity and posture of seed filling are restricted by the perforated ring, which creates a dispersed particle flow, thus enhancing the filling effect of the seeding plate and reducing energy consumption. The structural design of critical components is completed, and the principle of improving performance and energy efficiency is analyzed. The DEM simulation and bench experiment assisted in analyzing the effects of operating parameters on seed dynamic characteristics, seeding plate's filling performance, and operational energy consumption. Finally, the optimal parameter combination is determined. The result demonstrates that the number of teeth in the perforated ring was 21, accompanied by an improved seed-filling effect and lower energy consumption. The metering performance was optimal when the tooth length of the perforated ring was 8.65 mm, the center angle of the teeth was 8°, and the operating speed was 13.55 km/h. Moreover, the qualified rate was 94.5%, the multiple rate was 2.7%, and the leakage rate was 2.8%. The operating speed was in the range of 8–14 km/h, the qualified rate of the perforated seed-metering device was higher than 92.7 %, the leakage rate was lower than 5.4 %, the multiple rate was lower than 3.5 %, and the coefficient of performance was more than 9.2. Its energy efficiency was significantly better than that of the picker finger seed-metering device and the air-suction seed-metering device, thus satisfying the demands for an efficient and cleaner production of maize.

Design and Experiment of Air-Suction Maize Seed-Metering Device with Auxiliary Guide

Due to the irrational design of the seed discharge plate and the vacuum chamber, the high-speed seed filling effect of the air-suction maize precision seed-metering device is poor. Therefore, an air-suction maize seed-metering device with an auxiliary guide is designed to realize high-speed precision seed discharging. An auxiliary guide filling theory is put forward, and the design of the seed plate type hole charging structure is formulated. Fluent 2022 software is used to analyze nine kinds of vacuum chamber structures; the optimal vacuum chamber structure parameters were determined by polar analysis. In order to investigate the changes of negative pressure and flow speed under the dynamic flow field, a slip grid was used to analyze the dynamic flow field with three different operating speeds and negative pressures. It found that the size of negative pressure did not affect the flow field distribution, and the pressure and flow speed gradually decreased as the distance from the inlet was farther away; meanwhile, the negative pressure distribution and air speed distribution were almost unchanged when the holes at different rotational speeds were at the same position. Finally, bench tests were carried out, and three indexes, namely, the qualified index, the multiple index and the missing index, were selected, with operating speed and negative pressure as factors, two-factor five-level orthogonal test was carried out, and the optimal parameter combinations at 6.0, 7.5, 9.0, 10.5, and 12 km/h forward velocity were derived and verified by regression equations. The results showed that the designed seed-metering device was repeated five times when the pressure of the vacuum chamber was −3.5 kPa and the rotational speed of the seed-metering device was 23 r/min, the average grain spacing qualified index was 95.8%, the missing index was 1.6%, the multiple index was 2.6%, and the indexes met the requirements of precision sowing. It is of great significance for our country’s seeder to develop in the direction of high-speed and precision.

Design and experiment of the pneumatic double disc precision seed metering device for Chinese flowering cabbage

Design and experiment of the pneumatic double disc precision seed metering device for Chinese flowering cabbage

Design and Laboratory Experiments of A Pneumatic Disc-Type Garlic Precision Seed-Metering Device

Highlights A novel pneumatic disc-type garlic precision seed-metering device was designed. Numerical simulations of the airflow field inside the seed-metering device were carried out with FLUENT Software. The diameter of the suction hole, the rotational speed of the seed plate, and negative pressure were used to evaluate the performance of the seed-metering device. The reasonableness of the optimal combination of parameters was verified by a bench experiment. Abstract. To solve the problem of high seed damage rate and low transplanting efficiency on traditional mechanical garlic seed-metering devices, this article designed and experimented with a novel pneumatic disc-type garlic precision seed-metering device by using theoretical calculations and orthogonal experiments. The overall structure of the device and the basic principles of each working stage were described. Numerical simulations of the airflow field inside the seed-metering device were conducted with FLUENT software to determine the optimal location of the negative pressure outlet and the number of suction holes. A three-factor, three-level Box-Behnken quadratic rotation orthogonal combination experiment was carried out to evaluate the performance of the seed-metering device in terms of the qualified index, miss index, and multiple index. The results showed that the optimal combination of parameters was a suction hole diameter of 10.03 mm, a rotational speed of 11.70 rpm, and a negative pressure of 7.02 kPa. With the optimal combination of parameters, the seeding qualified index was 88.04%, the miss index was 8.65%, and the multiple index was 3.31%, which met the design requirements. The results of the bench experiment were basically consistent with the results under the optimal combination of parameters. This design can provide a theoretical basis for garlic’s precision transplanting. Keywords: Airflow field, FLUENT, Garlic’s precision transplanting, Orthogonal combination experiment, Seed-metering device.

Parameter optimization and experiment of the negative pressure precision seed-metering device for wheat

Parameter optimization and experiment of the negative pressure precision seed-metering device for wheat

Investigation of seeding performance of a novel high-speed precision seed metering device based on numerical simulation and high-speed camera

Numerical simulation and high-speed photography technology are used in this work to obtain the key factors affecting the seeding performance of a novel high-speed centrifugal filling-cleaning precision seeding metering device under different conditions. The effects of key parameters, including seed-metering diversion turbine structure, dynamic wind pressure, seed quantity, and ground speed, on the seeding performance of the high-speed seed metering device are investigated. The results show that a diversion turbine structure with diversion and controlled disturbance flow increases seed pressure and enhances the filling process. Meanwhile, a correlation between dynamic wind pressure and seed movement velocity is established using a high-speed camera-based experimental approach. Maintaining 24 internal seeds is crucial to guaranteeing the quality of feed index. Specifically, under the simulation conditions, when the ground speed is 14 km/h (corresponding to a rotation speed of 194.5 rpm), the corresponding dynamic wind pressure is identified as 1.5 kPa, the corresponding seed plate speed is 2 m/s, the corresponding optimal feeding rate should be maintained at about 14 seeds/s, and the seed inlet velocity is 3 m/s. Additionally, the results of comprehensive bench and field seeding performance experiments demonstrate that, as the seeding speed increases, there is no apparent seeding performance decline, and even under high-speed operational conditions, the quality of feed index under different ground speeds exceeds 90%.

Performance Optimization of a Spoon Precision Seed Metering Device Based on a Maize Seed Assembly Model and Discrete Element Method

To improve the sowing performance of the spoon wheel maize seeding machinery, in this paper, two varieties of maize seed are selected as examples. The maize spoon precision seed metering device, a core component of the spoon wheel seeding machinery, is used as the research object. The maize seed assembly model is first established based on the maize seed assembly modeling method. Its validity is verified by the sowing experiment and corresponding DEM simulation under the different revolving speeds of the seed metering wheel. Secondly, the performance of the spoon precision seed metering device is optimized by integrating the maize seed assembly model and multivariate nonlinear regression method. Therefore, the number of sub-spheres of the horse tooth, spherical cone, and spheroid maize seed model are 10–14, 18, and 6, respectively. The results show that the performance of the seed metering device improved when the revolving speed of the seed metering wheel, handing angle, and seed spoon radius are 25 r/min, 40°, and 7 mm, respectively. There is good agreement between the expected results and experimental ones with relative errors of less than 5%, and the optimized seed metering device facilitates the process of seed guiding and seed delivery during the sowing process.

Design and experiment of a centrifugal filling and cleaning high-speed precision seed metering device for maize

In this paper, a centrifugal filling and cleaning high-speed precision seed metering device for maize is designed based on the principle of centrifugal force generated by high-speed circular motion of seeds. Through theoretical analysis and calculation, the seeding tray and front shell of the seed metering device are designed so that the seeds can use centrifugal force for filling, cleaning, releasing, and returning. The seed metering device has a simple structure and can perform high-speed and precise seeding. A response surface experiment of central composite design was conducted with feeding and seeding speeds as experimental factors, and the omission rate, repeated rate, and pass rate as performance evaluation indexes. Through response surface experiment optimization, it was deduced that the highest seeding performance was achieved when the feeding and seeding speeds were 18.72 seeds/s and 15.12 km/h, respectively. Under these conditions, the omission, repeated, and pass rates were 2.21, 5.21, and 92.58%, respectively. The results of response surface experiment showed that, when the seeding speed of the centrifugal filling and cleaning high-speed precision seed metering device for maize is in the range of 10–20 km/h, the pass rate can be greater than 90%. In addition, the speed curve of feeding and seeding fitted from the bench experiment results is effective and reliable, which allows the seed metering device to achieve a precision seeding in a speed range of 10–20 km/h. The power of the air-suction seed metering device is 470.24 W when seeding at a speed of 14 km/h. Moreover, the power of the centrifugal filling and cleaning high-speed precision seed metering device is only 10.94 W when seeding at a speed of 20 km/h, and the energy consumption during seeding is much lower than that of the air-suction seed metering device, which performs cleaner production.

Accelerated verification method for the reliability of the motor drive mechanism of the corn precision seed-metering device

The current reliability analysis of the motor drive mechanism of the corn precision seed-metering device has yet to be validated by accelerated testing. Furthermore, the bench test used for verification does not consider the effect of vibration loads on the seeder during field operation. Therefore, this paper proposes an accelerated reliability verification method for the motor drive mechanism of the corn precision seed-metering device. Firstly, reliability theory is used to analyze the importance degree of motor drive system subcomponents. Then, various field tests were carried out to collect vibration and temperature rise data, to analyze the effect of field vibration on the motor drive mechanism, and to propose the vibration influence parameter k. Finally, an indoor test bench was set up, the formula of the acceleration factor A was modified, and accelerated verification tests on 96 motors were carried out to verify the method's accuracy. Reliability analysis showed that the motor’s importance degree was 79.31%, and the Hall switch was 19.78%. The field tests showed that the mean values of the vibration influence parameter k for the four seeding conditions (different seeding speeds) were 0.155, 0.186, 0.207 and 0.228. The accelerated tests showed that the absolute error between the accelerated verification test and the reliability analysis was 1.1% and 3.3% in importance degree and average life, respectively. This paper provided a solution for the reliability study and accelerated verification of the corn electric drive seed discharge mechanism.

Design and test of a pneumatic type of high-speed maize precision seed metering device

This study proposed a pneumatic type of high-speed maize precision seed metering device and analysed the motion mechanism of maize seeds during the filling, cleaning, and seed dropping processes of the device. Single-factor test methods were used to explore the influence of forward velocity, negative pressure of the seed metering device, and positive pressure of the seed guide tube on seeding performance separately. Additionally, based on high-speed camera technology, trajectory analysis was performed on continuously dropping maize seeds under different positive pressures of the seed guide tube. Results showed that an increase in positive pressure of the seed guide tube shortened the seed dropping time of maize seeds and made the time interval between adjacent maize seeds leaving the seed guide tube more uniform. Furthermore, a three-factor five-level orthogonal rotation combination test was used to explore the optimal working parameters of the pneumatic type of high-speed maize precision seed metering device. The results indicated that the optimal parameters were a forward velocity of 10 km/h, negative pressure of the seed metering device of 4.5 kPa, and positive pressure of the seed guide tube of 3 kPa. Verification tests demonstrated that the qualified index was 98.31% and the coefficient variation was 9.26%.

压持式玉米精量排种器的设计与试验

In order to further improve the seeding performance of the maize seed-metering device, a pressure-holding precision seed-metering device for maize was designed. The seed-metering device is made up of several seed rowing modules, which effectively solves the problems of inconvenient disassembly and complex maintenance of the current maize seed-metering device. The working principle of the device was introduced, and the mechanical and kinematic analysis of the maize seeds during the seeding operation was carried out. The orthogonal test was carried out with the installation diameter of seed-metering device's guide plate, torsion spring's wire diameter and seed-metering device's rotational speed as the test factors, the single-seeding rate, missed-seeding rate and multiple-seeding rate as the indexes, and the relationship between different test factors on the performance of seed-metering device was obtained. By optimizing the model, the best performance of the seed-metering device was obtained when the installation diameter of the guide plate was 92.32 mm, the wire diameter of the torsion spring was 1.59 mm, and the rotational speed of the seed-metering device was 0.41 r/s. At this time, the single-seed rate was 93.08%, the missed-seeding rate was 3%, and the multiple-seeding rate was 3.9%, which met the requirements of the industry standard.

Design and validation of a centrifugal variable-diameter pneumatic high-speed precision seed-metering device for maize

Design and validation of a centrifugal variable-diameter pneumatic high-speed precision seed-metering device for maize

Design and Experimental Study on a New Horizontal Rotary Precision Seed Metering Device for Hybrid Rice

In order to meet the sowing demand of the hybrid rice plug seedling, a horizontal rotary precision seed metering device was proposed. The key structure parameters were designed, the kinematics analysis of the seed-filling process was carried out, and the main influencing factors of the seeding performance evaluation index were determined. Taking motor speed, the eccentric distance of the disk, and seed layer thickness as test factors, and the taking qualification rate, repetition rate, and miss-seeding rate as seeding performance test indexes, the quadratic regression orthogonal rotation combination test was carried out, and the relationship between the test factors and evaluation indexes was approached by a quadratic polynomial. On the basis of discussing the influence of the test factors on the performance index, the regression surrogate mathematical model between the main performance index and the influencing factors was established. The value of the evaluation index of correlation degree p between the model variables was less than 0.01. Based on the regression surrogate mathematical model, the response surface of the qualified rate of the seeding performance evaluation index was established, and the test data were analyzed by multiple regression analysis. The rapid prediction of qualified rates under the influence of test factors was realized, and the optimum test parameters were obtained as follows: motor speed 165 r/min, an eccentric distance of disk 22 mm, seed layer thickness 28 mm, qualification rate 98.55%, miss-seeding rate 1.45%, and repetition rate 0%. According to the best combination of test parameters, the performance evaluation index test of the prototype was carried out, and the qualification rate, miss-seeding rate, and repetition rate were 98.34%, 1.66%, and 0%. The experimental results were in good agreement with the theoretical analysis, indicating that the horizontal rotary precision seed metering device can meet the agronomic requirements of hybrid rice. The research results could provide some reference for the design of a precision seeding device for industrialized plug seedlings.

Structural optimization method of rice precision direct seed-metering device based on multi-index orthogonal experimental.

To improve the mechanization level of rice planting, a new type of direct seeding device for rice was designed. The device's structural properties will be crucial in determining its seeding performance. Structure optimization in the current seed metering device design process focuses on a single or few indexes, resulting in improved individual performance but imbalanced overall performance. Therefore, a structure optimization method of the direct seeding device based on a multi-index orthogonal experiment was proposed in this study. First, the DEM-MBD coupling method observed the factors and levels that affected the performance overall. Second, a test platform based on the electric drive control model was constructed, and a multi-index orthogonal test was devised. Finally, the structural parameters of the seed metering devices were optimized based on matrix analysis. From the results, the primary and secondary levels of significance of factors were just as follows: hole diameter > hole number > adjustment angle. The following are the optimal parameters found by optimization analysis: the diameter of the hole was 12 mm, the number of holes was 10, and the adjustment angle was 80°. Validation tests were carried out and analyzed based on the optimal structural parameter combination. The qualification rate of seeds per hole, empty hole rate, average seed number, coefficient of variation of seed number, average hole spacing, and the variance coefficient of hole spacing are 93.07%, 0%, 9.39,14.04%, 22.84 cm, and 9.14%, respectively. In comparison to traditional design and structural parameter optimization methods for rice precision seed metering device, this study not just to provides an optimization scheme for improving the overall performance of rice precision seed metering device, but also serves as a technical reference for the development and design of new rice precision seed metering device.