Determination of Some Design Parameters for Roller Type Seed Metering Device

There are many design parameters in precision planters to be considered such as cell diameter, peripheral speed of roller, number of cells, manner of feeding seeds into cell and travel speed. In precision planters each cell must contain only one seed. Therefore, sliding the seed to the cell is important and depends on several parameters such as seed repose angle, seed dimensions and physics of cell. To help the seed to repose in the cell, making a groove on the roller would be very useful. Dimensions of this groove are very important and are considered as basic design parameters. This research was performed to determine some design parameters such as roller speed, travel speed, length and depth of groove for tomato seeds precision planting. In this regard, seeds with a diameter of 4 mm were used. The range of variation was based on calculations obtained. A roller with 42 mm width, 118 mm diameter and 15 cells on the surface was used in the experiment. For each cell, a triangular groove was created on the roller. The groove depth varied from zero at the beginning to the maximum value where the groove connected to the cell. The test unit had a continued and wide belt with 1 l m length. In each replication, planter worked for 20 s to reach a stable state. Thereafter, seeds were allowed to drop on the grease belt. Number of seeds and their spacing were measured on the 4.5 m of the belt. Results showed that the roller speed of 41.5 rpm, the planter travel speed of approximately 1 km/h, groove length of 6-8 mm and groove depth of 1.5 mm can improve planter performance for tomato pelleted seed.

Development of mechatronic driving system for seed meters equipped on conventional precision corn planter

Precision planters are more and more widely used for planting corn in China.Seed meters of conventional precision corn planters are usually driven by ground wheel and chain and sprocket system at present.Because of the slippage of ground wheels and vibration of chains,planting accuracy cannot be ensured,especially at higher forward speed.To improve the planting performance of precision planters,a mechatronic driving system was designed and its field working performance was evaluated in this research.A two-row pneumatic precision planter was modified to allow simultaneously using two different driving systems,i.e,with one row unit equipped with the newly designed mechatronic driving system and the other row unit equipped with conventional mechanical driving system,and used for planting at three forward speeds(9,11 and 12 km/h)on no-tillage and rotary-tillage lands.The distances between adjacent seeds in each plot were measured and the indices of uniformity in seed spacing,quality of feeding index(QFI),missing-seeding index and precision index were analyzed.With the average 4.70%increase of QFI and 3.54%decrease of missing-seeding index,the mechatronic driving system performed better than the mechanical driving system both on no-tillage and rotary-tillage lands at each forward speed.The values of QFI,missing-seeding index and precision index of the mechatronic driving system on rotary-tillage land are comparable to those on no-tillage land,by contrast,these indices of the mechanical driving system on rotary-tillage land are significantly worse than those on no-tillage land.The result indicates that the mechatronic driving system can eliminate the effect of ground wheel slippage on planting quality and maintain the uniformity of seed distribution.Although the QFI,missing-seeding index and precision index become worse with the increase of forward speed,with the worst values of QFI of 89.93%,missing-seeding index of 5.08%and precision index of 18.92%at the highest forward speed of 12 km/h,the mechatronic driving system can reduce the effect of forward speed on planting accuracy effectively.The result indicates that planters equipped with the mechatronic driving system are suitable for high speed planting.As compared to the mechanical driving system,the advantage of the mechatronic driving system is more noticeable especially when the forward speed is more than 11 km/h.

Global overview of research progress and development of precision maize planters

Maize is the most important crop for food and widely used for industrial materials,leading to its increasing demand all over the world.Precision planting is the effective method to increase maize yield.To meet the agronomic requirement of precision planting,different kinds of precision maize planters were developed.However,because of the difference of geographical environment,cropping system,farm scale and economic status among different countries,types of maize planters are various and the technologies involved are at different levels.This paper summarizes the precision maize planters currently available in the world and classifies them into four types:precision planters for tilled-land,minimum/no tilled-land,hilly&small land,and cold&arid land.Detailed characteristics have been provided for some typical precision planters and comparisons were made as to their suitability under particular working conditions.High-efficiency and high-accuracy are the main features of precision planters for tilled-land,while the ability to clean residue from seed rows and prevent planters to be blocked are the important function of precision planters for minimum/no tilled-land.To fit for hilly&small land,planters should be light-weighted and small-sized,and to warm up soil and keep moisture,planters for cold&arid land should be equipped with plastic-film mulching mechanism.Finally,developing trend of precision planting technology was analyzed and suggestions,including policy support and technical improvement,were made for developing countries to make suitable precision maize planters according to the local geographical conditions and cropping systems.

Study on multi-size seed-metering device for vertical plate soybean precision planter

Aiming to solve the problem of small range of the appropriately sowing seeds existing in a vertical disc seed-metering device,the planter plate series with four sizes were developed according to the variety and size distribution of all soybeans in China.The structure and working principle of the vertical disc soybean seed-metering device were detailed,and the influence of the diameter of soybean on the working performance of the seed-metering device was analyzed through the software EDEM virtual simulation,so as to achieve the goal of covering the soybean seeds with all sizes by the minimum planter plate series as well as to obtain the most appropriate operating speed of each planter plate by optimization.For the planter plates with the hole diameter of 7,9,12,16 mm,the appropriate size ranges of sowing seeds are 4.5-6.0,6.0-8.0,8.0-10.5,10.5-13.0 mm,respectively,and the appropriate operating speeds are 9,8,7,6 km/h,respectively.The results show that this planter plate series can meet the requirements of seeding with all sizes of soybeans at the range of the most appropriate operating speed.The study method can provide a reference for design and optimization of precision planters.

Design and test of fault monitoring system for corn precision planter

With the growing demand and working complexity of corn precision planter,it becomes more important to monitor the working performance through intelligent systems.A new fault monitoring system for corn precision planters was designed and tested.This system consisted of the information acquisition module,controller module,alarm module,input module and display module.A capacitive sensor was utilized to monitor the seed flow without changing the track of a precision planter.This system can monitor the whole sowing process of a seed-metering device in real-time.The sowing status,fault type and fault location can be displayed on liquid crystal display(LCD).Warning light on the LCD reminds the operator of abnormal conditions.Bench tests and field tests showed that the minimum monitoring accuracies of missing sowing and total sowing number were 92.11%and 94.28%,respectively,and the seed level sensor and the opener sensor worked well.This system can accurately prompt the seed-metering mechanism in real-time.

Novel low-cost control system for large high-speed corn precision planters

Large high-speed corn precision planters can significantly improve seeding efficiency,but at present,there is no mature control technology in China.This study proposed a novel low-cost control system for large high-speed corn precision planters based on multiple technologies such as embedded systems,controller area network(CAN),global positioning system(GPS),and Android development technology.The developed control system provided excellent expansion capabilities of more than 40 planter rows.Functions such as monitoring the planter status,adjusting seed density,calculating planting-area were realized.Field experiments were performed under different GPS frequencies(fGPS),travel speeds,and seed spacings.Results showed that the working area relative error index(REI)and fGPS were negatively correlated,and the planter can achieve 0.84%error under the fGPS of 10 Hz.When the travel speed was 10 km/h or 12 km/h,the average quality index(QI),miss index(MI),and precision index(PI)were superior to 92.84%,5.80%,and 18.57%under each seed spacing,respectively,QI and MI had no significant difference under each seed spacing(p<0.05).For a travel speed of 14 km/h,indexes values reached the worst level at seed spacing of 20 cm,but still met the requirements of Chinese national standards.The total cost of the control system for a 12-row corn precision planter is only 17.07%of similar products from abroad.In summary,the developed control system can achieve preferable performance and costs much less than similar products obtained from abroad,which is suitable for promotion in China or other developing countries.

Design of depth-control planting unit with single-side gauge wheel for no-till maize precision planter

No-till planters are very popular for maize seeding in fields covered with residue in annual wheat-maize double cropping system in North China Plain.However,there is no suitable depth control mechanism for existing no-till maize planters,and as a result,it is hard to obtain consistent planting depth,uniform emergence,and good passing ability at the same time.For the above reasons,a proper planting unit with a new type of depth-control mechanism was developed in this study.The mechanism consists of a single-side gauge wheel,a parallel four-bar linkage,a pair of double-disc opener,a V-shape press wheel and a depth regulator,which can adjust the planting depth from 30 mm to 90 mm to satisfy the agronomic requirement under different field conditions.Based on analysis and calculation,the width of gauge wheel was set to 50 mm while the length of parallel four-bar linkage was set to 350 mm.Field experiment was conducted and the results indicated that the newly designed planting unit with single-side gauge wheel performed well with regard to planting depth uniformity and anti-blocking ability.The planting depth uniformity and seed spacing quality were 95.45%and 91.90%,respectively,when the average height of stubble was 22.5 cm and residue amount was 0.64 kg/m^(2)in the field.It can satisfy the requirement of no-till maize planting on the cropland with residue and stubble in North China Plain.

Information acquisition system of multipoint soil surface height variation for profiling mechanism of seeding unit of precision corn planter

The emergence rate and vitality of maize are directly affected by the sowing depth,and the uniformity of this depth is an important performance indicator of a planter,while the effective soil surface height information acquisition is the prerequisite for ensuring the accuracy of sowing depth control.The soil surface height variation acquisition system of a precision corn planter often produces profiling errors when performing active profiling due to interference from ground debris.In this study,a multipoint soil surface height variation information acquisition system was investigated,which consists of a ranging sensor group and a microcontroller unit(MCU)using a data comparison and screening method.The structure and specifications of the ranging sensors were determined according to the soil surface height variation and debris size,and a nonessential profiling control program was developed.Performed tests on the information acquisition system indicated that the measurement accuracy of the system was 3 mm,and when advancing at a speed of 8 km/h,the accuracy of the profiling decision and the system stability were 97.1%and 94.1%,respectively,indicating that the system was capable of nonessential profile control.The designed ranging system could provide a reference for the design of a ground information acquisition system of precision planters with an active profiling mechanism.

Optimization design and experiment on ripple surface type pickup finger of precision maize seed metering device

A ripple surface type pickup finger was designed to improve the performance of pickup finger precision maize seed metering device and to provide a solution for precision maize planter.The main structure and working principle of seed metering device were detailed in this paper.The dimension size distributions of maize seeds in different types were studied,the gestures of seeds clamped by pickup finger were analyzed,and the clamping dynamical model of pickup finger was established by theoretical analysis.To optimize the structural parameters of ripple surface type pickup finger,the discrete element method(DEM)model of pickup finger precision maize seed metering device was established by the discrete element software EDEM.The numerical simulations of orthogonal seeding performance experiments were conducted to analyze the influences of these factors on the quality of seeding.The rotational speed,wavelength of ripple surface and amplitude of ripple surface were selected as the experimental factors.The average seeding qualified index and the average seeding coefficient of variation on four different types of maize seeds were chosen for evaluating the seeding performance.The results showed that,the average seeding qualified index was 93.35%and the average seeding coefficient of variation was 11.23%under conditions of the 25 r/min rotational speed,8 mm wavelength of ripple surface and 2 mm amplitude of ripple surface.Under the same condition,the bench test was done which showed that the results of test and simulation were consistent.The maximum error of qualified index was 1.95%and the qualified index of improved seed metering device exceeded the original one by 12.34%.The working performance can meet the requirements of precision maize seeding.

Effect of travel speed on seed spacing uniformity of corn seed meter

Both seeding performance of seed metering unit and travel speed of seed planter have significant effects on seeding quality,thereby affecting crop growth and yields.In order to determine the effects of different travel speeds on seed spacing uniformity,four different types of seed meters were evaluated at five different travel speeds on seed meter test bench and in field.The tested seed meters included a finger pickup seed meter,a scoop-wheel seed meter,an air-pressure type seed meter and an air-blowing type seed meter.The seeding performance of the horizontal distribution of seeds within a row was described by using the coefficient of variation,the quality of feed index,the multiple index and the miss-seeding index.Experiments were performed in laboratory and field,respectively.Results indicated that different travel speeds have statistically significant effects on seed spacing uniformity.The four types of seed meters performed better on the seed meter test bench than in the field.Coefficient of variation increases and quality of feed index decreases as the travel speed of seed planter increases.The best seed spacing uniformity was obtained with the air-pressure type seed meter,followed with the air-blowing type seed meter,the finger pickup seed meter and the scoop-wheel seed meter.There were considerable differences between the performances of the scoop-wheel seed meter in the bench test and field test;the seeding qualities were much better in the bench test than in the field test.The scoop-wheel seed meter is more sensitive to vibration than the other types of seed meters.

Optimizing the seed-cell filling performance of an inclined plate seed metering device using integrated ANN-PSO approach

Uniformseed distribution within the row is the prime objective of precision planters for better crop growth and yield.Inclined plate planters are generally used for sowing bold seeds likemaize,groundnut,chickpea,and their operating parameters like the forward speed of operation,the seedmetering plate inclination,and the seed level in the hopper affect the cell fill and subsequently the uniformseed distribution.Therefore,to achieve precise seed distribution,these parameters need to be optimized.In the present study,out of the different optimization techniques,a new intelligent optimization technique based on the integrated ANN-PSO approach has been used to achieve the set goal.A 3–5-1 artificial neural network(ANN)model was developed for predicting the cell fill of inclined plate seedmetering device,and the particle swarmoptimization(PSO)algorithmwas applied to obtain the optimum values of the operating parameters corresponding to 100%cell fill.The most appropriate optimal values of the forward speed of operation,the seed metering plate inclination,and the seed level in the hopper for achieving 100%cell fill were found to be 3 km/h,50-degree,and 75%of total height,respectively.The proposed integrated ANN-PSO approach was capable of predicting the optimal values of operating parameters with amaximumdeviation of 2%compared to the experimental results,thus confirmed the reliability of the proposed optimization technique.

Development of the peanut precision fertilization control system based on threshold velocity algorithm

In view of the fact that the current ground wheel velocimetry of the peanut precision fertilizer control system cannot solve the phenomenon of ground wheel slippage,and signal interference and delay loss cannot be excluded by BeiDou positioning velocimetry,a set of peanut precision fertilizer control system was designed based on the threshold speed algorithm.The system used STM32F103ZET6 microcontroller as the main controller,and touch screen for setting the operating parameters such as operating width,fertilizer type,and fertilizer application amount.The threshold speed algorithm combined with BeiDou and ground wheel velocimetry was adopted to obtain the forward speed of the tractor and adjust the speed of the DC drive motor of the fertilizer applicator in real time to achieve precise fertilizer application.First,through the threshold speed algorithm test,the optimal value of the length N of the ground wheel speed measurement queue was determined as 3,and the threshold of the speed variation coefficient was set to 4.6%.Then,the response performance of the threshold speed algorithm was verified by comparative test with different fertilization amounts(40 kg/hm^(2),50 kg/hm^(2),60 kg/hm^(2),70 kg/hm^(2))under two speed acquisition methods of ground wheel speed measurement and threshold speed algorithm(combination of Beidou single-point speed and ground wheel speed measurement)in different operation speeds(3 km/h,4 km/h,5 km/h).The response performance test results showed that the average value of the velocimetry delay distance of the BeiDou single-point positioning velocimetry method was 0.58 m,while the average value of that with the threshold velocity algorithm was 0.27 m,which decreased by 0.31 m and indicated more accurate with the threshold velocity algorithm.The field comparison test for fertilizer application performance turned out an over 96.08%accuracy rate of fertilizer discharge by applied with the threshold speed algorithm,which effectively avoided the inaccurate fertilizer application caused by wheel slippage and raised the accuracy of fertilizer discharge by at least 1.2%compared with that of using the ground wheel velocimetry alone.The results showed that the threshold speed algorithm can meet the requirements of precise fertilizer application.