Special Issue "Agricultural Structures and Mechanization"

A special issue of Agriculture (ISSN 2077-0472). This special issue belongs to the section "Agricultural Technology".

Deadline for manuscript submissions: closed (10 September 2021).

Special Issue Editor

Prof. Dr. José Pérez-Alonso
E-Mail Website
Guest Editor
Department of Engineering, University of Almería, Research Center CIMEDES, Agrifood Campus of International Excellence (ceiA3), Ctra. de Sacramento s/n, 04120 Almería, Spain
Interests: farm building; agricultural structures; rural landscape; greenhouses; agricultural machinery; precision farming; harvest technology; post harvest technology; irrigation; sensors; automation; safety and health; renewable energy; engineering and management

Special Issue Information

Dear Colleagues,

In our globalized world, the need to produce quality and safe food has increased exponentially in recent decades to meet the growing demands of the world population. This expectation is being met by acting at multiple levels, but mainly through the introduction of new technologies in the agricultural and agri-food sectors. In this context, agricultural, livestock, agro-industrial buildings, and agrarian infrastructure are being built on the basis of a sophisticated design that integrates environmental, landscape, and occupational safety, new construction materials, new facilities, and mechanization with state-of-the-art automatic systems, using calculation models and computer programs. It is necessary to promote research and dissemination of results in the field of mechanization and agricultural structures, specifically with regard to farm building and rural landscape, land and water use and environment, power and machinery, information systems and precision farming, processing and post-harvest technology and logistics, energy and non-food production technology, systems engineering and management, and fruit and vegetable cultivation systems (greenhouse structures and environmental control, plant protection and horticulture, harvesting in horticulture, fruit and vegetable cultivation).

This Special Issue focuses on the role that mechanization and agricultural structures play in the production of high-quality food and continuously over time. For this reason, it welcomes highly interdisciplinary quality studies from disparate research fields including agriculture, engineering design, calculation and modeling, landscaping, environmentalism, and even ergonomics and occupational risk prevention. Original research articles and reviews are accepted.

Prof. Dr. José Pérez-Alonso
Guest Editor

Manuscript Submission Information

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Keywords

  • farm building
  • agricultural structures
  • rural landscape
  • greenhouses
  • agricultural machinery
  • precision farming
  • harvest technology
  • post-harvest technology
  • irrigation
  • sensors
  • automation
  • safety and health
  • renewable energy
  • engineering and management

Published Papers (25 papers)

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Article
An Octopus-Inspired Bionic Flexible Gripper for Apple Grasping
Agriculture 2021, 11(10), 1014; https://0-doi-org.brum.beds.ac.uk/10.3390/agriculture11101014 - 17 Oct 2021
Viewed by 590
Abstract
When an octopus grasps something, the rigidity of its tentacle can change greatly, which allowing for unlimited freedom, agility, and precision. Inspired by this, a three-finger flexible bionic robot gripper was designed for apple picking. First, a flexible chamber finger was designed to [...] Read more.
When an octopus grasps something, the rigidity of its tentacle can change greatly, which allowing for unlimited freedom, agility, and precision. Inspired by this, a three-finger flexible bionic robot gripper was designed for apple picking. First, a flexible chamber finger was designed to drive the gripper finger to elongate, shorten, and bend, which works through a process of inflating and deflating. Further, we proposed a three-finger mode to achieve two kinds of motion states: grasping and relaxing, by simulating the movement of an octopus grasping at something. In this paper, we evaluated the bending property of the designed flexible bionic gripper through an apple grasping experiment. The experimental results show that the 100.0 g bionic gripper can load an apple with a weight of 246.5~350.0 g and a diameter of 69.0~99.0 mm, and the grasping success rate is 100%. It has a good grasping performance. Compared to other soft grippers, the proposed bionic flexible gripper has the advantages of being lightweight, and having good cushioning, low driving air pressure, and a strong grasping force. Full article
(This article belongs to the Special Issue Agricultural Structures and Mechanization)
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Article
Optimization and Experiment of Straw Back-Throwing Device of No-Tillage Drill Using Multi-Objective QPSO Algorithm
Agriculture 2021, 11(10), 986; https://0-doi-org.brum.beds.ac.uk/10.3390/agriculture11100986 - 10 Oct 2021
Viewed by 434
Abstract
Reducing operation energy consumption is the development demand of conservation tillage equipment. In order to solve the problems of high power consumption and the easy blockage of the no-tillage drill under full straw retention, the key parameters of the straw back-throwing device were [...] Read more.
Reducing operation energy consumption is the development demand of conservation tillage equipment. In order to solve the problems of high power consumption and the easy blockage of the no-tillage drill under full straw retention, the key parameters of the straw back-throwing device were optimized in this study. The Box–Behnken central combination test method was used to analyze the influence of the impeller rotating speed, feed quantity and cross-sectional area of the throwing pipe on the specific power consumption and throwing speed, the mathematical models of which were built with the aid of the least square method. In addition, the mathematical models were optimized by using a multi-objective quantum behaved particle swarm optimization (QPSO) with an improved target weighting coefficient. The optimization results indicated that, when the impeller rotating speed was 2287 r/min, the feed quantity was 1.1 kg/s and the cross-sectional area of the throwing pipe was 506.997 cm2, the specific power consumption and throwing speed by the models were 7528 m2/s2 and 11.73 m/s, respectively. The models were verified by comparing the optimization results with the measured data in the simulation filed tests, which proved that the multi-objective QPSO algorithm was feasible to optimize the working and structural parameters of the straw back-throwing device of the no-tillage drill under full straw retention. The results provide references for the parameter optimization of similar no-tillage drills under straw retention. Full article
(This article belongs to the Special Issue Agricultural Structures and Mechanization)
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Article
Research on Loading Method of Tractor PTO Based on Dynamic Load Spectrum
Agriculture 2021, 11(10), 982; https://0-doi-org.brum.beds.ac.uk/10.3390/agriculture11100982 - 09 Oct 2021
Viewed by 297
Abstract
The torque load spectrum is an important basis for the strength design and durability test verification of tractor power take-off (PTO), and the performance and reliability of tractor PTO directly affect the quality and efficiency of agricultural operations. In this paper, taking the [...] Read more.
The torque load spectrum is an important basis for the strength design and durability test verification of tractor power take-off (PTO), and the performance and reliability of tractor PTO directly affect the quality and efficiency of agricultural operations. In this paper, taking the PTO torque load as the object, a PTO loading method based on the dynamic load spectrum acquired in the actual field work was proposed in this paper. Based on the Peak Over Threshold model, the extrapolation of the PTO load spectrum was realized, and the load spectrum throughout the whole life cycle was obtained. On the basis of this, the mobile tractor PTO loading test bench and Fuzzy-Proportional-Integral-Derivative (Fuzzy-PID) controller were developed to achieve the dynamic loading of the PTO load spectrum, and the dynamic characteristics were analyzed and verified by the simulation and laboratory test. The results showed that with the time domain extrapolation method, the load extreme value was expanded from (63.24, 469.50) to (60.88, 475.18), and the coverage was expanded by 1.98%. By comparing with the fitting results, statistical characteristics and rain flow counting results, the load spectrum extrapolation method was effective. In addition, the response time of simulation and laboratory test were 0.05s and 0.75s, respectively; the maximum error was 1.77% and 4.03%, respectively; and the goodness of fit was 16.78 N·m, which indicated that the PTO loading test bench, can accurately restore the dynamic loading of the tractor and the Fuzzy-PID controller had better accuracy and stability. It would provide a reference for the practical application of PTO load spectrum of the tractors. Full article
(This article belongs to the Special Issue Agricultural Structures and Mechanization)
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Article
Effect of Planting Distance on the Mechanical Harvesting of Hot Pepper
Agriculture 2021, 11(10), 945; https://0-doi-org.brum.beds.ac.uk/10.3390/agriculture11100945 - 29 Sep 2021
Viewed by 447
Abstract
Hot peppers are well known for being spicy and also have a high nutrient content. Human resources have formerly been used to harvest hot peppers; however, a high level of musculoskeletal risk to the human workforce has been reported. Therefore, to reduce the [...] Read more.
Hot peppers are well known for being spicy and also have a high nutrient content. Human resources have formerly been used to harvest hot peppers; however, a high level of musculoskeletal risk to the human workforce has been reported. Therefore, to reduce the risk to farmers and replace the human workforce, the mechanical harvesting of hot pepper and steps to improve the harvesting efficiency of farmers were conducted. To achieve this, the effect of planting distance on the mechanical harvesting of hot peppers was analyzed at three planting distances (30, 40, and 50 cm) with several cultivars. Subsequently, machine-harvested hot peppers were classified into five groups (marketable, damaged, lost, unharvested, and twigged hot pepper), depending on their postharvest status. The average weight ratio of each group was then calculated, after which statistical analyses were conducted. The effect of planting distance on mechanical harvesting was then analyzed by comparing the differences between each group’s average weight ratio and the total weight of hot pepper, which was simultaneously harvested mechanically at each planting distance. Results showed that the average weight ratio of marketable, unharvested, and twigged hot pepper improved as the planting distance increased. However, no effect on the average weight ratio of damaged and lost hot pepper was observed. The highest yield of marketable hot pepper was found at a planting distance of 40 cm, and the average weight ratio to the whole was lower than at 50 cm of planting distance. Thus, the most suitable planting distance for mechanical harvesting was 40 cm. Full article
(This article belongs to the Special Issue Agricultural Structures and Mechanization)
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Article
Optimization Design and Experiment of Ear-Picking and Threshing Devices of Corn Plot Kernel Harvester
Agriculture 2021, 11(9), 904; https://0-doi-org.brum.beds.ac.uk/10.3390/agriculture11090904 - 21 Sep 2021
Viewed by 485
Abstract
In order to solve the problems of easy-to-break kernels and substantial harvest losses during kernel harvesting in breeding trials plot of corn, an ear-picking device and a threshing device of corn plot kernel harvester has been optimized. To automatically change the gap of [...] Read more.
In order to solve the problems of easy-to-break kernels and substantial harvest losses during kernel harvesting in breeding trials plot of corn, an ear-picking device and a threshing device of corn plot kernel harvester has been optimized. To automatically change the gap of the ear-picking plate, a self-elastic structure with compression spring and connecting rod is used. The ear-picking plate is glued, and an elastic rubber gasket is placed underneath it, which effectively improves the adaptability of the ear-picking device and reduces corn kernel collision damage during ear-picking. To ensure the self-purification of the ear-picking device, a combination of auger sieve hole cleaning device and lateral pneumatic auxiliary cleaning system is used. A dual-axial flow threshing device is designed, which uses a “U”-shaped conveying system to transport maize ears in the threshing chamber. The spacing of the concave sieve may be adjusted, and the residual kernels in the threshing chamber can be cleaned up after harvesting one plot by combining three cleanings, which meets the requirements of no mixing between plots. The force analysis of corn ears in the threshing chamber determines the best design plan for the forward speed, the speed of the second threshing drum, and the threshing gap. The breakage rate and non-threshing rate regression models were created using the quadratic regression orthogonal combination test, and the parameters were optimized using MATLAB. The verification test results showed that when the forward speed was 0.61 m/s, the second threshing drum speed was 500 r/min, and the threshing gap was 40 mm, the breakage rate was 1.47%, and the non-threshing rate was 0.89%, which met the kernel harvesting requirements in corn plots. Full article
(This article belongs to the Special Issue Agricultural Structures and Mechanization)
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Article
Optimization of Structure Parameters of the Grouser Shoes for Adhesion Reduction under Black Soil
Agriculture 2021, 11(8), 795; https://0-doi-org.brum.beds.ac.uk/10.3390/agriculture11080795 - 20 Aug 2021
Viewed by 495
Abstract
The black soil of Northeast China has a strong adhesion ability because of its unique physical properties, and the soil often adheres to the surface of the grouser shoes of tracked vehicles during the operation. The adhesion performance depends largely on structure parameters [...] Read more.
The black soil of Northeast China has a strong adhesion ability because of its unique physical properties, and the soil often adheres to the surface of the grouser shoes of tracked vehicles during the operation. The adhesion performance depends largely on structure parameters of the grouser shoes. The grouser height, the grouser thickness, and the grouser splayed angle were selected as structure parameters. The adhesion force and adhesive soil mass were selected as indicators of adhesion performance. Therefore, the mathematical model between structure parameters and response indicators was established by the response surface method (RSM). The optimal parameters combination was that the grouser height was 20 mm, grouser thickness was 6.34 mm, and grouser splayed angle was 40.45°. The average data of verification experiments occurred when the adhesion force reached 1.11 kPa and adhesive soil mass reached 22.68 g. Compared with the average value of un-optimized experiment results, the adhesion force and adhesive soil mass reduced by 12.84% and 4.63%, respectively. The relative error of the predicted values and measured values was less than 5%, proving the reliability of the regression models. This study could provide a reference method for parameters optimization, and a new structure of the grouser shoes of tracked vehicles will be designed to reduce adhesion. Full article
(This article belongs to the Special Issue Agricultural Structures and Mechanization)
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Article
Optimization of the Process Parameters of an Air-Screen Cleaning System for Frozen Corn Based on the Response Surface Method
Agriculture 2021, 11(8), 794; https://0-doi-org.brum.beds.ac.uk/10.3390/agriculture11080794 - 19 Aug 2021
Viewed by 515
Abstract
The threshing of frozen corn is accompanied by breakage and adherence, which influence the cleaning performance when the corn-cleaning mixture is separated and cleaned. In order to reduce the impurity ratio and loss ratio during frozen corn cleaning and provide theoretical support for [...] Read more.
The threshing of frozen corn is accompanied by breakage and adherence, which influence the cleaning performance when the corn-cleaning mixture is separated and cleaned. In order to reduce the impurity ratio and loss ratio during frozen corn cleaning and provide theoretical support for frozen corn combine harvesting, this study employed a self-made air-screen cleaning system with adjustable parameters. The optimal process parameters of frozen corn cleaning were determined by using the response surface method (RSM). The influences of the fan speed (FS), vibrational frequency (VF), and screen opening (SO) on the cleaning performance were explored. The results showed that all three process parameters had significant effects on the impurity ratio (IR) and loss ratio (LR). The fan speed had the most significant impact. The cleaning performance was optimal when the fan speed was 102.7 rad/s, the vibration frequency was 6.42 Hz, and the screen opening was 21.9 mm, corresponding to a 0.80% impurity ratio and a 0.61% loss ratio. The predicted values of the regression models were consistent with the experimental results with a relative error of less than 5%. The reliability and accuracy of regression models were established and confirmed. Full article
(This article belongs to the Special Issue Agricultural Structures and Mechanization)
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Article
Coupled Bionic Design Based on Primnoa Mouthpart to Improve the Performance of a Straw Returning Machine
Agriculture 2021, 11(8), 775; https://0-doi-org.brum.beds.ac.uk/10.3390/agriculture11080775 - 14 Aug 2021
Cited by 1 | Viewed by 571
Abstract
The high energy consumption and low crushing length qualification rate of traditional straw returning machines in the main maize-growing regions of northeast China make it difficult to promote straw returning operations in the region. The primnoa locust mouthpart is extremely efficient in cutting [...] Read more.
The high energy consumption and low crushing length qualification rate of traditional straw returning machines in the main maize-growing regions of northeast China make it difficult to promote straw returning operations in the region. The primnoa locust mouthpart is extremely efficient in cutting maize rootstocks. In this paper, it was found that there are significant differences between the primnoa locust mouthpart and the conventional machine, these exist mainly in the cutting edge structure and cutting motion. Thus, this paper develops a coupled bionic design for structural and kinematic coupling elements to develop a bionic straw returning machine. This paper found that the operating performance of the bionic straw returning machine was mainly affected by the blade rotation radius and the output rotation speed of the drive mechanism through DEM (discrete element method) simulation, and the optimal combination of the two parameters was 248 mm rotation radius and 930 r/min output rotation speed. Finally, this paper finds that the most obvious operational performance difference of the bionic straw returning machine compared with the traditional straw returning machine is that it can reduce the cutting power consumption by 9.4–11.7% and improve the crushing length qualification rate by 10.4–14.7% through the operational performance comparison test. Based on the above findings, this paper suggests that in future research and development of straw returning machines, more attention can be focused on finding suitable bionic prototypes and improving bionic design methods. Full article
(This article belongs to the Special Issue Agricultural Structures and Mechanization)
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Article
Study on the Distribution Pattern of Threshed Mixture by Drum-Shape Bar-Tooth Longitudinal Axial Flow Threshing and Separating Device
Agriculture 2021, 11(8), 756; https://0-doi-org.brum.beds.ac.uk/10.3390/agriculture11080756 - 09 Aug 2021
Viewed by 372
Abstract
To determine the distribution pattern of the threshing and separating device, the simulation experiment on the distribution pattern of our self-designed drum-shape bar-tooth longitudinal axial flow threshing and separating device was carried out with the help of the EDEM software, by which the [...] Read more.
To determine the distribution pattern of the threshing and separating device, the simulation experiment on the distribution pattern of our self-designed drum-shape bar-tooth longitudinal axial flow threshing and separating device was carried out with the help of the EDEM software, by which the axial and radial distribution curve of the threshed mixture along the cylinder was acquired. The three-dimensional distribution of the mass of the threshed mixture was drawn by using the Matlab software, and the bench test was carried out on the self-built small-scale longitudinal axial flow threshing cylinder performance test platform, which was consistent with the simulation conditions. The results showed that the axial and radial distribution of the threshed mixture was uneven, and the axial distribution of the threshed mixture decreased gradually, which was mainly distributed in the first third section of the cylinder. The distribution of the threshed mixture along the radial area of the cylinder was gradually decreasing at first and then increasing, i.e., the total mass of the threshed mixture on the left and right sides was higher than that of the middle area, which was basically consistent with the simulation results. The research can provide reference for the optimization of structural parameters of threshing and separating device and cleaning system. Full article
(This article belongs to the Special Issue Agricultural Structures and Mechanization)
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Article
Experimental Evaluation of Rootstock Clamping Device for Inclined Inserted Grafting of Melons
Agriculture 2021, 11(8), 736; https://0-doi-org.brum.beds.ac.uk/10.3390/agriculture11080736 - 02 Aug 2021
Viewed by 535
Abstract
A grafting machine is a kind of machine that can quickly graft scion to rootstock instead of manual grafting. Currently, an inclined inserted grafting machine uses the mechanical clamping method, which can easily damage the rootstock seedlings due to its high stiffness, thus, [...] Read more.
A grafting machine is a kind of machine that can quickly graft scion to rootstock instead of manual grafting. Currently, an inclined inserted grafting machine uses the mechanical clamping method, which can easily damage the rootstock seedlings due to its high stiffness, thus, reducing the success rate of grafting. This study proposed an effective, flexible clamping device for grafting. The suction hole diameter (HD), the negative pressure (NP), and the surface inclination angle (IA) of the clamping device were studied via a single factor experiment to obtain optimal parameter ranges. Optimal HD, NP, and IA were 2–3 mm, 4–8 kPa, and 10–20°, respectively. The orthogonal experiment results showed that the optimal parameter combination for maximum holding success rate was HD, 2.5 mm; NP, 6 kPa; and IA, 10°. The experimental verification was carried out using the optimal parameter combination, with a holding success rate of 98.3% and no damage. This study provides a reference for the optimal design of an inclined inserted grafting machine. Full article
(This article belongs to the Special Issue Agricultural Structures and Mechanization)
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Article
An Investigation of Pull-Out Force of Semi-Buried Lotus Roots after Hydraulic Scouring
Agriculture 2021, 11(8), 706; https://0-doi-org.brum.beds.ac.uk/10.3390/agriculture11080706 - 27 Jul 2021
Viewed by 488
Abstract
Hydraulic scouring is the most effective approach to harvest lotus roots, but its application is largely restricted by the low harvesting rate. After hydraulic scouring, some mature lotus roots are still partially buried in the soil. Therefore, it is highly necessary to develop [...] Read more.
Hydraulic scouring is the most effective approach to harvest lotus roots, but its application is largely restricted by the low harvesting rate. After hydraulic scouring, some mature lotus roots are still partially buried in the soil. Therefore, it is highly necessary to develop an appropriate approach to harvest semi-buried lotus roots. In this work, we for the first time studied the interaction between semi-buried lotus roots and soil, as well as analyzing the pull-out process and the factors affecting the pull-out force of semi-buried lotus roots. Firstly, a simple testing platform was designed based on the virtual prototype technology and the tests on pull-out force were conducted on five lotus roots with similar shape but different weights, with the burial depth and pull-out speed as the experimental factors. The results revealed that the maximum pull-out force is not significantly affected by the pull-out speed, whereas it is significantly influenced by the burial depth and the surface area of lotus roots. The maximum pull-out force increased with increasing lotus root surface area and burial depth. In addition, the discrete element method was employed to simulate the pull-out process of lotus root at different pull-out speeds. The simulation results indicated that a higher pull-out speed would result in a greater pull-out force at the same displacement of the lotus root from the soil. Both experimental and simulation results revealed that soil adhesion contributes the most to the pull-out resistance. It was also observed that a slight loosening of semi-buried lotus roots could drastically reduce the pull-out force. These results suggest that some kind of mechanical structure or improvement of water flow can be applied to the existing lotus root harvester to reduce the adhesion between lotus roots and soil. Overall, our findings provide a novel direction for optimizing hydraulic harvesting machines of lotus roots. Full article
(This article belongs to the Special Issue Agricultural Structures and Mechanization)
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Article
Design and Experimental Research on Soil Covering Device with Linkage and Differential Adjustment of Potato Planter
Agriculture 2021, 11(7), 665; https://0-doi-org.brum.beds.ac.uk/10.3390/agriculture11070665 - 14 Jul 2021
Viewed by 536
Abstract
When the potato planter works on sloping field, it will cause problems such as poor film mulching quality due to the difference in volume of soil covering both sides of the discs and the inconvenient adjustment of the soil covering disc. The soil [...] Read more.
When the potato planter works on sloping field, it will cause problems such as poor film mulching quality due to the difference in volume of soil covering both sides of the discs and the inconvenient adjustment of the soil covering disc. The soil covering device with linkage and differential adjustment was designed to improve the mulching quality. The main research content includes explaining the structure and principle of the soil covering device and analyzing the structural parameters of the adjustment mechanism. The field experiment was completed to verify the performance of soil covering device, which takes the stability coefficient and uniformity coefficient of the volume of covering soil as factors. The result shows the following: (1) The volume of covering soil changes exponentially with the angle of the disc through data fitting, which can standardize the angle of covering disc; and (2) when the angle of disc is 30° and 60°, respectively, the uniformity coefficient of volume of covering soil is lower than 1.4, which has premium soil covering quality. When the angles of the discs on both sides differ greatly, the stability coefficient of volume of covering soil is 0.41, which can meet the requirements of the mulching quality of potato planter. This research provides the technical support for high-quality potato planting. Full article
(This article belongs to the Special Issue Agricultural Structures and Mechanization)
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Article
Development of Thermal Performance Metrics for Direct Gas-Fired Circulating Heaters
Agriculture 2021, 11(7), 588; https://0-doi-org.brum.beds.ac.uk/10.3390/agriculture11070588 - 24 Jun 2021
Viewed by 439
Abstract
Many climate-controlled agricultural buildings use direct gas-fired circulating heaters (DGFCH) for supplement heat. There is no standardized test to calculate thermal efficiency for these heaters. This study aimed to develop a measurement system and analytical analysis for thermal efficiency, quantify the measurement uncertainty, [...] Read more.
Many climate-controlled agricultural buildings use direct gas-fired circulating heaters (DGFCH) for supplement heat. There is no standardized test to calculate thermal efficiency for these heaters. This study aimed to develop a measurement system and analytical analysis for thermal efficiency, quantify the measurement uncertainty, and assess economics of DGFCH efficiency. The measurement system developed was similar to the ASHRAE 103 standard test stand with adaptations to connect the apparatus to the DGFCH. Two different propane measurement systems were used: input ratings < 30 kW used a mass flow system and input ratings > 30 kW used a volumetric gas meter. Three DGFCHs (21.9, 29.3, 73.3 kW) were tested to evaluate the system. Thermal efficiencies ranged from 92.4% to 100.9%. The resulting uncertainty (coverage factor of 2; ~95% Confidence Interval) ranged from 13.1% to 30.7% for input ratings of 56.3 to 11.4 kW. Key sources of uncertainty were propane and mass flow of air measurement. The economic impact of 1% difference in thermal efficiency ranged from USD $61.3 to $72.0 per heating season. Refinement of the testing system and procedures are needed to reduce the uncertainty. The application of this system will aid building designers in selection of DGFCHs for various applications. Full article
(This article belongs to the Special Issue Agricultural Structures and Mechanization)
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Article
Equipment Performance, Costs and Constraints of Packaging and Transporting Rice Straw for Alternative Uses to Burning in the “Parc Natural l’Albufera de València” (Spain)
Agriculture 2021, 11(6), 570; https://0-doi-org.brum.beds.ac.uk/10.3390/agriculture11060570 - 21 Jun 2021
Viewed by 471
Abstract
Rice straw is a residue that causes significant environmental problems, as burning it causes CO2 and ash emissions, while buried waste can cause issues associated with eutrophication. The extraction of straw from fields for alternative uses may contribute to solving these problems, [...] Read more.
Rice straw is a residue that causes significant environmental problems, as burning it causes CO2 and ash emissions, while buried waste can cause issues associated with eutrophication. The extraction of straw from fields for alternative uses may contribute to solving these problems, but research into its economic viability is necessary. The straw can be used for crop mulching, biofuel, bedding for livestock, and so on. In this study, we analyse the work carried out by straw harvesting machines (rakes, balers, bundlers, and loaders) and calculate the costs of packing, road-siding, and transportation of the straw from the rice fields to stockage points in the producer area, as well as to locations outside of the rice production area, in order to assess the viability. The costs of all elemental operations were calculated. The costs of all the operations included between raking and unloading in the producer area stocking point ranged between 28.1 and 51 EUR t−1. These costs were compared with the price of rain-fed cereal straw (wheat and barley), which is the most abundant, noting that the years in which rain-fed cereal straw reached high prices, rice straw could serve as a competitive product; however, in years when the former is cheap, it would be necessary to subsidise the harvesting of rice straw. Full article
(This article belongs to the Special Issue Agricultural Structures and Mechanization)
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Article
Evaluation of the Effect of Different Hand-Held Sprayer Types on a Greenhouse Pepper Crop
Agriculture 2021, 11(6), 532; https://0-doi-org.brum.beds.ac.uk/10.3390/agriculture11060532 - 09 Jun 2021
Viewed by 750
Abstract
The cultivation of vegetables in greenhouses is characterised by high planting density and environmental conditions that favour the development of pests and diseases. These are mainly controlled using plant protection products applied with a hand-held sprayer. This is inefficient low-tech equipment that is [...] Read more.
The cultivation of vegetables in greenhouses is characterised by high planting density and environmental conditions that favour the development of pests and diseases. These are mainly controlled using plant protection products applied with a hand-held sprayer. This is inefficient low-tech equipment that is difficult to calibrate. The study evaluates one hand-held spray gun and two hand-held spray lances that are widely used in greenhouse vegetable crops. The tests were carried out on a pepper crop at two different developmental stages. Plant canopy deposition and losses to the ground were quantified using a colorimetric method based on applying a tartrazine solution. The results show that the flat-fan spray lance obtains a more uniform spray distribution in the plant canopy and results in losses to the ground that are between 2 and 2.75 times less than when using the other hand-held sprayers tested. Full article
(This article belongs to the Special Issue Agricultural Structures and Mechanization)
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Article
Design and Experiment of Row-Controlled Fertilizing–Weeding Machine for Rice Cultivation
Agriculture 2021, 11(6), 527; https://0-doi-org.brum.beds.ac.uk/10.3390/agriculture11060527 - 06 Jun 2021
Viewed by 791
Abstract
Current approaches to topdressing and weeding operations for rice cultivation present several disadvantages, such as poor precision, low efficiency, serious environmental pollution, and so on. This paper presents a row-controlled fertilizing–weeding machine to improve the precision of fertilizing and weeding operations and to [...] Read more.
Current approaches to topdressing and weeding operations for rice cultivation present several disadvantages, such as poor precision, low efficiency, serious environmental pollution, and so on. This paper presents a row-controlled fertilizing–weeding machine to improve the precision of fertilizing and weeding operations and to reduce the heavy pollution associated with rice cultivation. A proportional–integral–derivative algorithm was adopted to realize accurate fertilization control, and an automatic driving system for agricultural machinery based on BeiDou navigation was used for accurate row-controlled operation. Accuracy testing and field experiments were carried out. The results show that the fertilization control system can stabilize the speed to within 0.55 s of the desired speed with a standard deviation of around 0.32 r·min−1. The row-controlled operation ensures the lateral deviation is within ± 5 cm at operating speeds below 5 km·h−1. The high uniformity and accuracy of fertilization meet agronomic requirements and rice cultivation standards, and the weeding performance is acceptable at working speeds below 5 km·h−1. Full article
(This article belongs to the Special Issue Agricultural Structures and Mechanization)
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Article
Influence of Mechanical and Intelligent Robotic Weed Control Methods on Energy Efficiency and Environment in Organic Sugar Beet Production
Agriculture 2021, 11(5), 449; https://0-doi-org.brum.beds.ac.uk/10.3390/agriculture11050449 - 15 May 2021
Cited by 3 | Viewed by 821
Abstract
Rapidly warming climate, tightening environmental requirements, an aging society, rising wages, and demand for organic products are forcing farming to be more efficient and sustainable. The main aim of this study was to perform an analytical analysis and to determine the energy use [...] Read more.
Rapidly warming climate, tightening environmental requirements, an aging society, rising wages, and demand for organic products are forcing farming to be more efficient and sustainable. The main aim of this study was to perform an analytical analysis and to determine the energy use and GHG emissions of organic sugar beet production using different weed control methods. Seven different methods of non-chemical weed control were compared. Mechanical inter-row loosening, inter-row cutting and mulching with weeds, weed smothering with catch crops, and thermal inter-row steaming were performed in field experiments at the Experimental Station of Vytautas Magnus University (Lithuania, 2015–2017). The other three, namely, automated mechanical inter-row loosening with cameras for row-tracking, inter-row loosening with a diesel-powered robot, and inter-row loosening with an electric robot were calculated analytically. The results showed that the average total energy use of organic sugar beet production was 27,844 MJ ha−1, of which manure costs accounted for 48–53% and diesel fuel for 29–35%. An average energy efficiency ratio was 7.18, while energy productivity was 1.83 kg MJ ha−1. Analysis of GHG emissions showed that the total average GHG emissions to the environment from organic sugar beet production amounted to 4552 kg CO2eq ha−1, and the average GHG emissions ratio was 4.47. The most sustainable organic sugar beet production was achieved by using mechanical inter-row loosening with a diesel-powered robot for weed control. Full article
(This article belongs to the Special Issue Agricultural Structures and Mechanization)
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Article
Design, DEM Simulation, and Field Experiments of a Novel Precision Seeder for Dry Direct-Seeded Rice with Film Mulching
Agriculture 2021, 11(5), 378; https://0-doi-org.brum.beds.ac.uk/10.3390/agriculture11050378 - 21 Apr 2021
Cited by 3 | Viewed by 689
Abstract
Existing devices for dry direct-seeded rice with film mulching in northern China have limitations such as imprecise sowing, unadjustable sowing depth, and seeding device blocking. In this regard, this study proposes a combined seeding method of ‘mini shovel + telescopic pipe’ for dry [...] Read more.
Existing devices for dry direct-seeded rice with film mulching in northern China have limitations such as imprecise sowing, unadjustable sowing depth, and seeding device blocking. In this regard, this study proposes a combined seeding method of ‘mini shovel + telescopic pipe’ for dry direct-seeded rice with film mulching. A precision seeder for dry direct-seeded rice with film mulching was developed through theoretical calculations, discrete element modelling (DEM) simulations, and field experiments. The configuration and diameter of the rollers were obtained. Twelve telescopic pipes were evenly distributed on the circumference of the roller, with a contact ratio exceeding one. This ratio reduced the slip rate of the roller effectively. Subsequently, DEM was used to develop a 33 central composite design. The response surface was established with the sowing depth as the response value. According to agronomic requirements, the sowing depth was set to 20 mm. The optimal combination of working parameters was obtained by optimizing the regression equation. The field experiments showed that the performance of the precision seeder for dry direct-seeded rice with film mulching satisfied the requirements of agricultural production, working stably and reliably. The developed device represents a useful solution for dry direct-seeded rice with film mulching. Full article
(This article belongs to the Special Issue Agricultural Structures and Mechanization)
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Article
Structural Optimization and Performance Evaluation of Blocking Wheel-Type Screw Fertilizer Distributor
Agriculture 2021, 11(3), 248; https://0-doi-org.brum.beds.ac.uk/10.3390/agriculture11030248 - 14 Mar 2021
Cited by 3 | Viewed by 838
Abstract
In order to solve the problem where the amount of screw fertilizer distributor can only be adjusted by rotating speed and poor fertilization uniformity at low rotational speeds, a blocking wheel-type screw fertilizer distributor was designed. Single factor and L9(34 [...] Read more.
In order to solve the problem where the amount of screw fertilizer distributor can only be adjusted by rotating speed and poor fertilization uniformity at low rotational speeds, a blocking wheel-type screw fertilizer distributor was designed. Single factor and L9(34) orthogonal simulation tests based on EDEM software were carried out to optimize the distributor variables at a speed of 20 r/min. The bench verification test was built under the same conditions as the simulation tests to verify the results of the simulation. Finally, the bench performance tests were carried out to evaluate distributor performance. The results of simulation tests revealed that the minimum coefficient of variation of fertilization uniformity (CVFU) was 19.27%, with the structural parameter combination of the inner diameter (17 mm), pitch (45 mm), outlet distance (40 mm), and number of screw heads (1). The verification test results showed that the changing trend and values of the CVFU were almost the same as the simulation tests. The results of the performance test revealed that when the opening width of the blocking wheel was 10–30 mm and the rotation speed was 20–60 r/min, the amount of fertilizer per lap (FAPL) was in the range of 27.74–38.15 g/r; the maximum CVFU and the coefficient of variation of fertilization stability (CVFS) were 29.43% and 2.18%, respectively, which met the requirements of the industry standard. This research provides a good reference for optimizing the screw fertilizer distribution and for researchers in the field of precision fertilization. Full article
(This article belongs to the Special Issue Agricultural Structures and Mechanization)
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Article
Deviation Tolerance Performance Evaluation and Experiment of Picking End Effector for Famous Tea
Agriculture 2021, 11(2), 128; https://0-doi-org.brum.beds.ac.uk/10.3390/agriculture11020128 - 05 Feb 2021
Cited by 1 | Viewed by 702
Abstract
Accurately obtaining the posture and spatial position of tea buds through machine vision and other technologies is difficult due to the small size, different shapes, and complex growth environment of tea buds. Therefore, end effectors are prone to problems, such as picking omission [...] Read more.
Accurately obtaining the posture and spatial position of tea buds through machine vision and other technologies is difficult due to the small size, different shapes, and complex growth environment of tea buds. Therefore, end effectors are prone to problems, such as picking omission and picking error. This study designs a picking end effector based on negative pressure guidance for famous tea. This end effector uses negative pressure to guide tea buds in a top-down manner, thereby correcting their posture and spatial position. Therefore, the designed end effector has deviation tolerance performance that can improve the picking success rate. The pre-experiment is designed, the tip of apical bud is referred to as the descent position, and the negative pressure range is determined to be 0.6 to 0.9 kPa. A deviation tolerance orthogonal experiment is designed. Experimental results show that various experimental factors are ranked in terms of the significance level of the effect on the average success rate, and the significance ranking is as follows: negative pressure (P) > pipe diameter (D) > descent speed (V). An evaluation method of deviation tolerance performance is presented, and the optimal experiment factor-level combination is determined as: P = 0.9 kPa, D = 34 mm, V = 20 mm/s. Within the deviation range of a 10 mm radius, the average success rate of the negative pressure guidance of the end effector is 97.36%. The designed end effector can be applied to the intelligent picking of famous tea. This study can provide a reference for the design of similar picking end effectors for famous tea. Full article
(This article belongs to the Special Issue Agricultural Structures and Mechanization)
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Article
Longitudinal Axial Flow Rice Thresher Performance Optimization Using the Taguchi Technique
Agriculture 2021, 11(2), 88; https://0-doi-org.brum.beds.ac.uk/10.3390/agriculture11020088 - 20 Jan 2021
Cited by 1 | Viewed by 666
Abstract
Combine harvesters are widely used worldwide in harvesting many crops, and they have many functions that cover the entire harvesting process, such as cutting, threshing, separating, and cleaning. The threshing drum is the core working device of the combine harvester and plays an [...] Read more.
Combine harvesters are widely used worldwide in harvesting many crops, and they have many functions that cover the entire harvesting process, such as cutting, threshing, separating, and cleaning. The threshing drum is the core working device of the combine harvester and plays an influential role in rice threshing efficiency, threshing power requirement, and seed loss. In this study, two structures of rice threshers (conical-shaped and cylindrical-shaped) were tested and evaluated for performance under different thresher rotating speeds of 1100, 1300, and 1500 rpm and different feeding rates of 0.8, 1.1, and 1.4 kg/s. The experiment was designed using the Taguchi method, and the obtained results were evaluated using the same technique. The thresher structure and operating parameters were assessed and optimized with reference to threshing efficiency, required power, and productivity. The obtained results revealed that increasing thresher rotating speed and the feeding rate positively related to threshing efficiency, power, and productivity. The highest efficiency of 98% and the maximum productivity of 0.64 kg/s were obtained using the conical-shaped thresher under a 1500 rpm rotating speed and a feed rate of 1.4 kg/s, whereas the minimum required power of 5.45 kW was obtained using the conical thresher under a rotating speed of 1100 rpm and a feed rate of 0.8 kg/s. Full article
(This article belongs to the Special Issue Agricultural Structures and Mechanization)
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Article
A Novel Semiautomatic Flesh Peeling and Seed Removing Mechanism for Dried Longan
Agriculture 2021, 11(1), 48; https://0-doi-org.brum.beds.ac.uk/10.3390/agriculture11010048 - 10 Jan 2021
Viewed by 1040
Abstract
Longans, which are produced in tropical countries, are rich in nutrients and high in commercial value. To extend their shelf life, fresh longans are roasted to dry them out. For the convenience of cooking applications, the dried longan pulp is peeled and seeded [...] Read more.
Longans, which are produced in tropical countries, are rich in nutrients and high in commercial value. To extend their shelf life, fresh longans are roasted to dry them out. For the convenience of cooking applications, the dried longan pulp is peeled and seeded beforehand. Presently, this is done manually; thus, this research aims to automate this process. A cutting tool with a serrated bending angle is used to cut the dried longan pulp, and then the longan is fixed by a lifting mechanism. The pulp is breached with a cutting tool and this breach is pushed up against a 6 mm hole in the silicone soft plate of the lifting mechanism to separate out the seed by squeezing. Commercially available dried longans are used in this experiment. The cutting surface width of the cutter designed in this study is 20 mm, and the serration bending angle is 30°. This cutter operates at a speed of 29 cm/s on dried longan pulp, attaining a success rate of 85%. The lifting mechanism also presented in this study fixes the dried longan and uses a squeezing motion to separate the flesh from the seed with a silicone soft plate. Here, a lifting speed of 28 mm/s achieves the highest rate of success at peeling, and the success rate of pulp-and-seed separation can reach 86.7%. Full article
(This article belongs to the Special Issue Agricultural Structures and Mechanization)
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Review

Jump to: Research

Review
Current Knowledge and Future Directions for Improving Subsoiling Quality and Reducing Energy Consumption in Conservation Fields
Agriculture 2021, 11(7), 575; https://0-doi-org.brum.beds.ac.uk/10.3390/agriculture11070575 - 23 Jun 2021
Viewed by 547
Abstract
Subsoiling has been acknowledged worldwide to break compacted hardpan, improve soil permeability and water storage capacity, and promote topsoil deepening and root growth. However, there exist certain factors which limit the wide in-field application of subsoiling machines. Of these factors, the main two [...] Read more.
Subsoiling has been acknowledged worldwide to break compacted hardpan, improve soil permeability and water storage capacity, and promote topsoil deepening and root growth. However, there exist certain factors which limit the wide in-field application of subsoiling machines. Of these factors, the main two are poor subsoiling quality and high energy consumption, especially the undesired tillage depth obtained in the field with cover crops. Based on the analysis of global adoption and benefits of subsoiling technology, and application status of subsoiling machines, this article reviewed the research methods, technical characteristics, and developing trends in five key aspects, including subsoiling shovel design, anti-drag technologies, technologies of tillage depth detection and control, and research on soil mechanical interaction. Combined with the research progress and application requirements of subsoiling machines across the globe, current problems and technical difficulties were analyzed and summarized. Aiming to solve these problems, improve subsoiling quality, and reduce energy consumption, this article proposed future directions for the development of subsoiling machines, including optimizing the soil model in computer simulation, strengthening research on the subsoiling mechanism and comprehensive effect, developing new tillage depth monitoring and control systems, and improving wear-resisting properties of subsoiling shovels. Full article
(This article belongs to the Special Issue Agricultural Structures and Mechanization)
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Review
Research Progress and Development of Mechanized Potato Planters: A Review
Agriculture 2021, 11(6), 521; https://0-doi-org.brum.beds.ac.uk/10.3390/agriculture11060521 - 03 Jun 2021
Viewed by 912
Abstract
Potato is one of the most important crops in the world to ensure food security for the world’s fast-growing population. Mechanized planting is crucial for improving production and per unit area yield of potato. To meet the agronomic requirements of potato planting, various [...] Read more.
Potato is one of the most important crops in the world to ensure food security for the world’s fast-growing population. Mechanized planting is crucial for improving production and per unit area yield of potato. To meet the agronomic requirements of potato planting, various types of potato planters have been developed according to the existing differences in geographical environment, cropping system, farm scale, and economic status among different countries and regions. This paper summarizes the research progress and application status of potato planters all over the world. Specifically, the seed-metering devices of potato planters are classified firstly. Then, potato planters are classified into three types: potato planters for manual/animal, two-wheel tractor, and four-wheel/crawler tractor traction. Furthermore, the characteristics of some typical commercial potato planters are discussed. Finally, some suggestions are proposed in order to promote the development of potato planters. Full article
(This article belongs to the Special Issue Agricultural Structures and Mechanization)
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Review
Applications of Discrete Element Method in the Research of Agricultural Machinery: A Review
Agriculture 2021, 11(5), 425; https://0-doi-org.brum.beds.ac.uk/10.3390/agriculture11050425 - 08 May 2021
Cited by 1 | Viewed by 942
Abstract
As a promising and convenient numerical calculation approach, the discrete element method (DEM) has been increasingly adopted in the research of agricultural machinery. DEM is capable of monitoring and recording the dynamic and mechanical behavior of agricultural materials in the operational process of [...] Read more.
As a promising and convenient numerical calculation approach, the discrete element method (DEM) has been increasingly adopted in the research of agricultural machinery. DEM is capable of monitoring and recording the dynamic and mechanical behavior of agricultural materials in the operational process of agricultural machinery, from both a macro-perspective and micro-perspective; which has been a tremendous help for the design and optimization of agricultural machines and their components. This paper reviewed the application research status of DEM in two aspects: First is the DEM model establishment of common agricultural materials such as soil, crop seed, and straw, etc. The other is the simulation of typical operational processes of agricultural machines or their components, such as rotary tillage, subsoiling, soil compaction, furrow opening, seed and fertilizer metering, crop harvesting, and so on. Finally, we evaluate the development prospects of the application of research on the DEM in agricultural machinery, and look forward to promoting its application in the field of the optimization and design of agricultural machinery. Full article
(This article belongs to the Special Issue Agricultural Structures and Mechanization)
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