INMATEH - Agricultural Engineering

25-43

Authors: Wenwen SONG, Yu WAN, Bo ZHOU, Fuming KUANG, Wei XIONG, Juan LIAO, Dequan ZHU, Shun ZHANG

In order to solve the problems of unstable seeding quantity and poor applicability of traditional lightweight simplification mechanical seed-metering device, a combined cavity-type rice precision hole-drop seed-metering was developed. According to the material characteristics of rice seed and the requirements of seeding quantity, the innovative metering hole structure achieves the purpose of accurate filling of rice seed. In order to adapt to the demands of different rice seeds and improve the accuracy and convenience of the adjustment of the seeding quantity, the number of cavities involved in seeding operation was simply adjusted. Bench tests are carried out on the effects of the seed-inlet width, the metering hole slope angle, and the cavity outer angle on the precision seeding performance of the seed-metering device. The test results show that when the outer and middle seed-inlets width both are 3.8 mm, the innermost seed-inlet width is 5.4 mm, and the metering hole slope angle is 35 °, and the cavity outer angle is 85 °, the performance of the three kinds of rice was better. Opening outermost seed-inlet to seeding super hybrid rice, the qualified rate is 90.67%, the miss-seeding rate is 3.77%. Opening outer and middle seed-inlets to seeding hybrid rice, the qualified rate is 90.80%, the miss-seeding rate is 3.73%. Opening all three seed-inlets to seeding conventional rice, the qualified rate is 90.67%, the miss-seeding rate is 3.53%. The field test shows the seed-metering device can also meet the requires of these kinds of rice seeding.

53-69

Authors: Chenwei HU, Jiayu CAO, Shuo ZHANG, Yu CHEN, Liquan LU

As an important plant protection machinery for spraying and fertilizing crops, high clearance self-propelled sprayer is of great significance to promote food security production and stable development of agriculture. Aiming at the complex operating conditions and unique operating requirements of large high clearance self-propelled sprayer, this paper analyzes and determines the main components of the sprayer suspension, such as elastic components, guiding devices, buffer devices, damping components, etc., and designs a stand-alone vertical shaft air suspension system structure suitable for high clearance sprayers. The stress of the sprayer chassis under different extreme conditions such as side slip, emergency braking and uneven road driving is analyzed, and the vertical shaft is designed and checked in detail. Based on the stress analysis results of the sprayer chassis, the finite element analysis software HyperMesh 10.0 was used to analyze the statics of the key components of the suspension, such as the vertical shaft, the motor protection shell, the steering arm, and the spring top support. According to the results of force analysis and finite element analysis, combined with the requirements of process production, the suspension structure in the design scheme is improved, and the final suspension form and the whole structure scheme of the sprayer are obtained. Through this study, it provides a basis for the design and development of large high clearance self-propelled sprayer.

83-92

Authors: Mykhailo ANELIAK, Alvian KUZMYCH, Serhii STEPANENKO, Viktor LYSANIUK

The article presents the results of studies of the process of threshing leguminous grass seeds with a drum-type threshing device. The process of material movement in the working gap of the drum deck was modelled and the intensity of the action of the working on the material under optimal operating conditions was substantiated. The dependence of the completeness of threshing alfalfa seeds on the number of rasp bar actions on the material on pendulum copra and in a threshing device was obtained based on the results of laboratory research. The influence of the design and technological parameters of the threshing device on the efficiency of threshing alfalfa seeds, as well as on the energy indicators of their operation, has been determined. The rational parameters of the threshing device are substantiated, which ensure complete threshing of seeds at the level of 96.5-98.2%, and damage to no more than 0.8% of seeds.

103-114

Authors: Bin WANG, Lili LI

In order to perform highly effective identification of external defects and increase the additional value of Cerasus Humilis fruits, this study used hyperspectral imaging technology to collect information on intact and defective Cerasus Humilis fruits. Based on the full transition spectrum, partial least squares discriminant analysis (PLS-DA) and back propagation neural networks (BPNN) were used to establish a discriminative model. The competitive adaptive reweighted sampling (CARS) was used to extract feature wavelengths, principal component analysis was used for data compression of single band images, BPNN and convolutional neural networks (CNN) were used for defect Cerasus Humilis fruits recognition of principal component images. The results showed that the overall detection accuracy of PLS-DA and BPNN models based on wavelength spectral information were 83.81% and 85.71%, respectively. BPNN was used to establish the calibration model based on the selected characteristic wavelengths by CARS, the accuracy rate was 90.47%. The classified accuracy of CNN model based on principal component images was 93.33%, which was obviously better than that of BPNN model at 83.81%. The research shows that the CNN model was successfully applied to the detection of Cerasus Humilis fruits defects using hyperspectral imaging. This study provides a theoretical basis for the development of fruit grading and sorting equipment.

124-135

Authors: Linwei LI, Yanbo SONG, Jie SUN, Yuanyuan LU, Lili NIE, Fumin MA, Xinyu HOU, Juxia LI, Yanwen LI, Zhenyu LIU

Maize eyespot and maize curvularia leaf spot are two diseases that often occur on maize leaves. Because of the similarity of the shape and structure, it is difficult to identify the two diseases just relying on the observation of the growers. For the harmfulness and prevention methods are different, it would cause great loss if the disease can't be identified accurately. To address this issue, this paper first employs a connected region feature recognition method to design an automated lesion cropping process after acquiring leaf images with several lesions. Subsequently, a lesion recognition model based on the AlexNet architecture is built and subjected to five-fold cross-validation experiments. The results indicate that the model achieves a comprehensive recognition accuracy exceeding 99%. To further comprehend model characteristics, an analysis of the recognition accuracy and its fluctuations is conducted, revealing that the fractal growth and biological characteristics of the lesions may influence the recognition results. Moreover, the distribution of model parameters could be a potential reason for fluctuations in recognition accuracy rates with increasing number of iterations. This paper could offer valuable reference and support for the intelligent identification and diagnosis of maize and other plant diseases.

147-163

Authors: Petru CARDEI, Nicolae CONSTANTIN, Cătălin PERSU, Vergil MURARU, Raluca SFÎRU, Maria IAMANDEI, Daniel LATES

The aim of the research is to highlight some statistical tools that favour extracting the components of the dynamic process that are dependent on the forward speed of some agricultural aggregates. The main objectives are: (I) identification of a minimum number of components in a multitude of random variables, with the help of which the other random variables can be calculated, and the application of this result to the strain gauge measurements; (II) establishing the connection between the synthetic results that partially solve the first objective and the forward speed of the agricultural aggregate. The second objective is used to obtain indications in search of the parameters’ dependencies on the forward speed of the aggregate. The first objective seeks to determine a group of three signals from the twelve, with the help of which the best multivariate linear interpolation is obtained for the other nine signals, which in physical terms means the reduction to a quarter of the measurement points and of the strain sensors used. A result associated with the first objective refers to the estimation of information loss due to the limited number of deformation sensors mounted on the tested structure. The article also presents attempts to use the results of the theory of neural networks and statistical interaction. In order to capitalise on the experimental data in this complex statistical framework, it is necessary to monitor at least the working speed (not only the average speed per experiment), fuel consumption, working depth (continuously monitored), soil moisture etc.

173-184

Authors: Qian DONG, Guohai ZHANG, Yuqian ZHAO, Fukang ZHOU, Peng LIU, Yihu WANG, Xipeng QIAN

Aiming at the traditional FMECA (Failure Modes, Effect and Criticality Analysis) results of the threshing and cleaning system, which are strongly influenced by subjective factors, imprecise and easy to repeat, the fuzzy comprehensive evaluation method is introduced to quantify the results of the expert evaluation and reduce the subjective influence. Analytic Hierarchy Process (AHP) is used to assign weights to each influencing factor, and by calculating the comprehensive hazard level index, the hazard ranking of each failure mode is carried out, from which the critical failure modes are identified as the focus of improvement, so as to improve the reliability of the system. Comparison shows that the improved method effectively makes up for the shortcomings of the traditional FMECA analysis method, and it is easier to find out the critical failure modes, which provides a theoretical basis for practical application.

194-204

Authors: Yaxiu HOU, Shuqi SHANG, Xiang LI, Xiaoning HE, Haifeng ZHENG, Tongtong DONG, Xu LI, Zhixin LIU, Shuai YANG, Dongwei WANG

Aiming at the problems of low threshing efficiency and high damage rate of current threshing devices. In this study, the operational form of the threshing drum and the structure of the threshing element were innovated, and a new threshing drum with low damage and high efficiency was designed. Using EDEM software, flexible body modeling of corn kernels, cobs and whole ears was carried out. The dynamic analysis of the corn threshing process was completed and the simulation parameters were further optimized. The optimum operating parameters were analyzed by orthogonal rotational tests and response surface method with a speed of 800 r/min for the threshing drum, a clearance of 10 mm for the concave plate and 30 mm for the threshing drum. The radius of the round head of the threshing element was 5 mm. The height of the threshing element was 60 mm. The final threshing efficiency was 98.78% and the damage rate of threshing was 0.62%. The results show that the new threshing device can meet the requirements of low-loss threshing devices for corn combine harvesters and can provide a theoretical basis for the development of the theory and technical system of corn plot combine harvesters in the future.

215-224

Authors: Biao XIE, Jinyin BAI, Jiagang YAN, Shibo ZHAO, Nian LIU, Qiang ZHANG

Aiming at the lack of discrete element simulation models and parameters for rice polishing, grading, color sorting and other technologies and equipment, and the difficulty of guiding equipment design and optimization through simulation, this paper calibrates the simulation parameters of white rice based on angle of repose (AOR) test and simulation methods. Huanghuazhan and Dongnong 429 white rice were selected as research object. Numerical model of white rice was established by multi-sphere filling. According to physical test and references, the simulation parameter range of white rice particles was determined. Plackett-Burman test was used to screen parameters, and it was found that the particle-particle static friction coefficient and particle-particle rolling friction coefficient had significant effects on the AOR of white rice. The regression model between the AOR and the significance parameter was established according to the central composite design method. The simulation parameter combination that has significant influence on the physical AOR was determined through the optimization design, and verified by the simulation test. The simulation AOR was compared with the physical AOR, and the relative error of the two kinds of white rice was less than 3%. The results show that the calibration method proposed in this study can accurately simulate the physical AOR test, which can provide reference for discrete element simulation of white rice processing.

237-247

Authors: Fang LI, Xiaohu BAI

During the operation of a boom sprayer, various excitations can cause the boom to roll, yaw, or jolt, which can negatively impact the spray effect. In order to maintain the stability of the boom, it is crucial to incorporate a suspension between the vehicle body and the boom. This study established a dynamic model that describes the roll of a boom mounted on a double-pendulum suspension. The transfer function and frequency response function of the passive suspension were obtained, with the ground slope angle as input and the boom inclination angle as output. The analysis results showed that the passive suspension can partially isolate high-frequency disturbances but cannot follow low-frequency signals. For the active suspension, the transient and frequency responses were analyzed by numerical integration algorithm, the harmonic balance method and numerical solution. The results indicated that the active suspension can enable the boom to follow the ground slope, track low-frequency signals to a certain extent, and isolate high-frequency signals. The proposed mathematical model can be utilized to analyze the dynamic characteristics and provide guidance for the double-pendulum suspension design.

259-270

Authors: Shike GUO, Min FU, Xiaoman CUI, Zijan WANG, Chengmeng WANG

For the standardized apple orchards in China, which are mainly dwarfed and densely planted, firstly, according to the spatial distribution characteristics of fruits within the tree canopy, a clamping-pull-off apple picking robot was developed by analyzing the parameters of apple cultivation and picking methods, in order to replace the manual harvesting operation. Then, the D-H method was used to establish the kinematic Equations of the apple-picking robot, the forward and inverse kinematic calculations were carried out, and the Monte Carlo method was used to analyze the workspace of the robot. Through the robot picking task planning and the simulation of the trajectory of the robotic arm, the scheme of the robot's picking strategy was given, and MATLAB software was applied to simulate the motion trajectory as well as to verify the feasibility of the trajectory planning scheme and the picking strategy. Finally, an apple-picking test bed was set up, the corresponding picking control system program was designed, and 45 apples were selected for picking tests. The results showed that during the robot's picking process, the average time for picking each fruit was 7.59 seconds, the fruit recognition success rate was 86.67%, and the picking damage rate was 5.13%.

282-289

Authors: Zhouhua LIU, Xin YOU, Penghui QIAO, Mengjun CHEN, Weiwei CHEGN

Passive solar greenhouses are developing rapidly in China and they can significantly increase crop yields. The main reason for this increase in crop yield is the availability of a suitable thermal environment. In order to investigate the thermal environment of the heliostats in the high latitude water-scarce and cold region of Shanxi, the thermal environment of the heliostats in this region was measured in this paper, and the results showed that the highest temperature of the heliostats was located in the eastern part of the crop area at about 4m from the back wall; the highest and lowest temperatures of the heliostats were located in the eastern part of the crop area;the maximum and minimum temperatures in the greenhouse were located in the eastern part of the crop area, and the temperatures in most of the crop area exceeded 30°C. This research can provide theoretical support for the construction and management of solar greenhouses in low heat and water areas at high latitudes.

301-318

Authors: Haijun BI, Pengcheng JIA, Kuan QIN, Lei YU, Chengmao CAO, Dongsong XIA, Xinliang GUO, Yang LIU, Bin CHEN, Yuzhen BI

The gas–solid coupling of a porous hot-air tea de-enzyming and carding machine was studied by means of computational fluid dynamics and discrete element coupling. In the numerical model, the discrete phase of tea particles was simulated using Rocky-DEM software, while the gas phase was described by ANSYS Fluent software. A mathematical model of the movement characteristics of tea particles in air was established according to the principle of fluid mechanics, to carry out dynamic analysis of tea particles’ movement process and derive how the motion of gas and tea particles is governed. Three sets of prototype tests were carried out on the basis of the design and simulation, and the average of their results taken. This showed that the hourly output of the test prototype was 3.89 kg/h, the bar-type rate was 89.14%, the de-enzyming moderation rate was 91.67%, and the average value of the measured effective operating temperature of the pot slot was 189 °C. The performance of the prototype was also tested and analyzed. After conducting a tea sensory evaluation expert appraisal, the sensory evaluation indices of the prototype-processed tea satisfied all current market requirements, being superior to those of the conventional de-enzyming and carding machine. The quality of the finished tea also met the agronomic standards and the operational requirements of the de-enzyming and carding machine.

327-334

Authors: Guoliang YOU, Yaoming LI, Hanhao WANG

The value of high moisture content crops is higher and the planting area is wider. However, in the harvest process, due to the high moisture content, the cleaning loss is greater. In order to reduce the adhesion between the crop extraction mixture and improve the cleaning performance, a method of hot air cleaning was proposed. By using the fan design theory and thermodynamics, the prototype design of the hot air fan was completed. Through orthogonal test, the most suitable parameter combination is 1445r/min fan speed and 85℃ air inlet temperature. Computational fluid dynamics (CFD) was used to observe the air velocity and air temperature of the outlet under the optimal combination of parameters to check whether it meets the requirements of hot air cleaning. The reliability of numerical simulation was tested by bench test. Finally, a field experiment was carried out with the hot air fan to observe the difference between the cleaning effect and the fan under the optimal parameter combination, and compare the cleaning loss rate.

345-355

Authors: Kuizhou JI, Yaoming LI, Binbin JI, Zhenwei LIANG, Tuo DU

In this paper, the basic rigid unit and discrete element rigid model of reed stem and discrete element flexible model of reed stem were established by means of multi-spherical filling and other methods. Then, three-point bending test was carried out in EDEM software to complete the calibration of bonding parameters. Finally, simulation analysis was carried out with the loss rate as the index. The simulation results show that the optimal parameter combination is 46 r/min for the transverse transmission device, 53 r/min for the vertical clamping longitudinal transmission device, and 470 mm for the center distance of the drum. Finally, the initial field test verifies that the maximum parameter combination of the harvester header is 49 r/min for the transverse conveying device of the header, 51 r/min for the vertical clamping longitudinal conveyor and 1.1 m/s for the field forward speed of the reed harvester, and the loss rate of the harvester is 3.36%, and the optimal parameter combination is consistent with the simulation analysis results.

367-378

Authors: Svitlana YUKHYMCHUK, Serhii YUKHYMCHUK, Mykola TOLSTUSHKO, Igor TSIZ, Nataliya TOLSTUSHKO

The article describes a new design of the disc-belt flax-pulling apparatus, which will increase the durability of the pulling belts and reduce the material consumption of the flax gleaning machine. The geometrical parameters of the pulling section of the disc-belt flax-pulling apparatus have been established. The energetics of the process of picking flax stalks, which are clamped in the curved longitudinal pulling stream of the disc-belt flax-pulling apparatus, have been theoretically investigated. The dynamics of changes in the components of pulling power when moving the flax stalk along the pulling stream were studied, depending on: the initial inclination of the flax stalk; from the forward speed of the flax harvester; from the angle of inclination of the pulling apparatus to the horizon. The energy per second of pulling and the value of its components are determined.

391-405

Authors: Zhiguo PAN, Tianfeng SUN, Xiaomeng WANG, Qiuqiang HOU, Shiting LV, Luming ZHANG, Zhenfei YANG, Xuehui ZHANG

To overcome inadequate functional integration, irregular pits, and insufficient agricultural machinery and agronomy in tobacco seedling transplanting equipment under film, a digging transplanting integrated machine was built. The machine uses parallel four-bar mechanism. The excavation equipment uses conical spiral blades. Using the trajectory approach, the four bar mechanism's fundamental parameters can be reversed. This method meets the requirements for coordinated excavation and transplantation. Mechanical study of soil units determines upward movement characteristics. Additionally, spiral angle, spiral blade outer diameter, and spiral blade speed are quantified to affect soil movement. The range of factors is derived. Based on three factors binary regression orthogonal combination simulated optimization experiment, a discrete element analysis was performed to enhance parameters. Experimental factors optimized include a spiral angle of 19°, a spiral blade diameter of 378 mm, and a rotational speed of 258 rpm. The two optimized test indicators are: a 193 mm hole depth and 350 mm hole diameter. The improved results were verified by field validation studies using a 191 mm hole depth and 347 mm hole diameter. The simulation optimization results and field validation experiment results are very similar. This study provides a technical basis for tobacco farming concurrent drilling and transplanting research.

419-428

Authors: Shandong YANG, Chuang MA, Baochang ZHANG, Yinping ZHANG, Jinchang YANG

Aiming at the problems of low land utilization and serious water waste in the existing wheat planting pattern, a two-high and two-low wheat high-low border spaced apart planting mode was proposed, and a high and low borders wheat no-till planter that can finish stubbing, fertilization, border construction, seeding and other tasks was designed. The design and analysis of the ship-type ridging device were carried out, and the construction process was simulated to determine the optimal parameters. A field test was carried out, the average sowing depth was 3.17 cm, the qualification rate was 95%, the standard deviation was 0.38 cm, and the coefficient of variation was 12.06%. The average value of the width of the seedling belt was 9.40 cm, the qualification rate was 91.67%, the standard deviation was 0.29 cm, and the coefficient of variation was 3.09%. The average height difference between the high and low borders was 9.26 cm, the pass rate was 100%, the standard deviation was 0.35 cm, and the coefficient of variation was 3.83%. The average width of the borders was 52.18 cm, the qualified rate of the border width was 100%, the standard deviation was 1.00 cm, and the coefficient of variation was 1.93%. The differences between each index and the theoretical design are small and meet the agronomic requirements.

441-450

Authors: Xihang SUN, Ziwen GUO, Guanghui WANG, Chen CAI, Zhiqin WANG

This study analyzes the drying of alfalfa using hot air, infrared and combined drying techniques. Different temperatures, radiation heights, radiation power and wind speed are used as control factors, and drying time, color, crude protein and specific energy consumption are used as evaluation indicators. After assigning weights to each indicator, the comprehensive evaluation index is calculated. The comprehensive evaluation index of alfalfa drying after combined drying is between 1.00 and 1.30, which is overall higher than hot air drying and infrared drying. Combined drying technology can effectively improve the efficiency and quality of the alfalfa drying process.

459-469

Authors: Zeyuan YAN, Ming SUN

In recent years, the problem of “rural labor shortage” in China has become increasingly serious, with a large number of young laborers going out to work, leading to an increasing amount of idle rural land. The intensification of population aging and the reduction of agricultural labor force in China resulted in an urgent demand for agricultural robots. With the rapid development of agricultural machinery and automation technology, agricultural robots have been continuously developing. They can better adapt to the development of biotechnology in agriculture, and traditional harvesting methods may undergo significant changes, with an increased focus on the cultivation of crops. Therefore, this paper introduces a new encoding scheme on the basis of traditional genetic algorithm (GA) and proposes an improved double encoding GA. This new encoding scheme is used on the crossover link, whereas the path node sequence encoding scheme is still used on the mutation link. The selection operation is placed after the mutation, and the merging sorting and elitist selection are performed on the parent population, crossover population, and mutation population before selection, thereby accelerating the convergence speed. On the basis of the improved GA, the three-dimensional path of the apple harvesting robot is designed and planned, with the addition of adaptive adjustment function during the progress. The experimental simulation results show that the three-dimensional path planning of the apple harvesting mobile robot based on the improved GA can minimize the number of paths and loops and well meet the operational requirements of the harvesting robot.

483-498

Authors: Adrian IOSIF, Edmond MAICAN, Sorin BIRIȘ, Lucretia POPA

Quality assessment of apples is a pivotal task in the agriculture and food industries, with direct implications for economic gains and consumer satisfaction. Traditional methods, whether manual, mechanical or electromechanical, face challenges in terms of labor intensity, speed, and quality control. This paper introduces a solution using machine learning algorithms – specifically, Convolutional Neural Networks (CNNs) – for a more nuanced and efficient apple quality assessment. Our approach offers a balance between the high-speed capabilities of electromechanical sorting and the detailed recognition achievable with human evaluation. A dataset consisting of over 2000 apple images, labeled as 'Good' or 'Damaged', was compiled for training and validation purposes. The paper investigates various architectures and hyperparameter settings for several CNN models to optimize performance metrics, such as accuracy, precision, and recall. Preliminary evaluations indicate that the MobileNet and Inception models yield the highest levels of accuracy, emphasizing the potential of machine learning algorithms to significantly enhance apple quality assessment processes. Such improvements can lead to greater efficiency, reduced labor costs, and more rigorous quality control measures.

511-521

Authors: Iuliana GĂGEANU, Florbela CARVALHEIRO, Adam EKIELSKI, Luis C. DUARTE

The focus of the research was to evaluate the use of lignin from different sources as an agent for the removal of diverse types of microplastics when present in wastewater. Organosolv lignin was obtained from three different sources (Miscanthus sp., pine bark and solid anaerobic digestates from Organic Fraction of Municipal Solid Wastes) by an ethanol-based organosolv treatment carried out in a pressurized stirred-tank reactor. The lignins obtained were evaluated as an adsorbent for diverse types of microplastics: High-density polyethylene (HDPE), Polystyrene (PS), Expanded Polystyrene (EPS), and Polypropylene (PP). All lignins used had the capacity to capture plastic particles from all plastic types, but a differential absorbance potential was found both for plastic types and lignin samples. EPS was the least adsorb type for all lignin sources, with the remaining plastics presenting equivalent results. Pine bark lignin was the best adsorbent among the tested feedstocks, always presenting the best performance for all plastic types. The direct utilization of organosolv hydrolysates, avoiding lignin recovery presented a similar behaviour. These results open the possibility to develop new natural, plant-based, adsorbents for microplastic removal from contaminated wastewater.

535-547

Authors: Fengkui ZHANG, Wenxi SHAO, Shijie ZHAO, Jikui ZHU, Ping LI

To improve the quality of air suction jujube picker, the CFD-DEM coupled method is used to numerically simulate the conveying process of jujube particles and explore the motion state, particle collision and energy loss of jujube particles in the pipeline. The erosion rate is selected as an evaluation index to discuss the influence of wind velocity, bending angle and diameter on the conveying process. The simulation results show that the collisions between jujubes, as well as the collisions between jujubes and pipe wall have an impact on the conveying performance, and the latter is more significant. The erosion rate is positively correlated with the wind velocity, negatively correlated with the pipe diameter, and the bending angle first decreases and then increases. The influence degree of factors on the erosion rate is: wind velocity > bending angle > pipeline diameter. The optimal parameter combination is a wind velocity of 28 m•s-1, a bending angle of 105 °, and a pipe diameter of 130 mm. At this time, the value of erosion rate is the lowest and the number of collisions and energy loss between jujube particles are reduced by 37.3 % and 13.87 % year-on-year, and those between jujube particles and pipe wall are reduced by 17.45 % and 17.61 % year-on-year, respectively. The test results show that the conveying pipe with optimized structural parameters can reduce the jujube skin damage rate by 2.06 %. The results of this study can provide a reference for the design and optimization of the air suction jujube picker.

558-565

Authors: George IPATE, Constantin Daniel COTICI, Alina-Daiana IONESCU, Viorel FATU, Iuliana GAGEANU, Dan CUJBESCU, Ana Maria NICOLAU

In this research, the data from temperature measurements obtained with the InfiRay T2S+ device, an infrared thermal imaging camera have been checked to monitor plant thermal behaviour. Plant leaf temperature is a parameter frequently used as representative for stomatal conductance, as stomatal confinement results in attenuated transpiration, and consequently leads to increased plant temperature. Also, to identify the stress of the plant, indices of thermal and modified stress have been calculated. The results obtained show that the Kalanchoe blossfeldiana species chosen for this study, when exposed to extreme values of temperature or water requirements, presented significant changes in the infrared electromagnetic wave spectra.

573-582

Authors: Qian SUN, Yang SONG, Zhigang YANG, Xiaorui LIU, Shimao CUI

Chinese solar greenhouses (CSGs) are the important agricultural building facility with highly efficient and sustainable utilization of solar energy. In order to improve the thermal insulation performance and reduce the heat loss, different insulation cover measures were applied to Chinese solar greenhouses. In this study, a solar greenhouse with an internal insulation blanket (SG1), a greenhouse with an internal blanket and an internal plastic film (SG2) and a greenhouse with an external blanket, an internal blanket and an internal plastic film (SG3) were chosen as experimental objects to analyze their indoor temperature environment. The results indicated that the differences of solar radiation interior among three greenhouses were similar, which was not the main reason that caused the differences of the temperature environment in the three greenhouses. During the tests, the nighttime average temperature was increased by 2.1-3°C by adding the cover materials, and the duration of nighttime temperature greater than 8°C was increased by 33.5%-38.2%. In addition, the cost is increased by adding the insulation cover materials, but it will be beneficial for greenhouse production to reduce additional energy consumption.

599-610

Authors: Jinbao LIU, Xuan ZHENG, Yanhui ZHANG, Yuying SONG, Zhihui TANG

During the tillage of two-way ploughing equipment in rocky and barren soil, due to hard objects such as stones, the plough and the key working parts such as plough column are deformed and broken, thereby reducing the reliability and service life of machines and tools. As such, an anti-overload automatic obstacle avoidance mechanism for two-way ploughing is developed. The maximum obstacle avoidance height is 40 cm, and the obstacle avoidance angle α is designed. The rotation range is 4.6 ~51.5°, and the effective compression stroke of the spring after pre-tightening is 39.34 mm. The motion equation and quasi-static force equation of the mechanism are established. The plowing resistance in the equilibrium state is 9.74 KN, and the required spring preload is 9.75 KN. Under the safety factor of 1.3, different spring elastic coefficients change with the rotation angle of the mechanism. The virtual prototype simulation model of the anti-overload automatic obstacle avoidance mechanism is established. The simulation results show that the mechanism can effectively perform the obstacle avoidance action. Bench test verifies that the mechanism can avoid obstacles according to the predetermined load. The field test shows that the stability coefficient of the ploughing depth of the mechanism is less than 8%. The results can effectively realize the obstacle avoidance function and ensure the farming quality, and provide an efficient and reliable anti-overload obstacle avoidance structure and parameter basis for the rocky land.

625-636

Authors: Lijuan FAN

Currently, drones have been gradually applied in the field of agriculture, and have been widely used in various types of agricultural aerial operations such as precision sowing, pesticide spraying, and vegetation detection. The use of agricultural UAVs for pesticide spraying has become an important task in the agricultural plant protection process. However, in the crop spraying process of agricultural UAVs, it is necessary to traverse multiple spray points and plan obstacle avoidance paths, which greatly affects the efficiency of agricultural UAV crop spraying operations. To address the above issues, traditional particle swarm optimization (PSO) algorithms have strong solving capabilities, but they are prone to falling into local optima. Therefore, this study proposes an improved PSO algorithm combined with the A* algorithm, which introduces a nonlinear convergence factor balancing algorithm for global search and local development capabilities in the traditional PSO algorithm, and adopts population initialization to enhance population diversity, so that the improved PSO algorithm has stronger model solving capabilities. This study designs two scenarios for agricultural UAV crop spraying path planning: one without obstacles and one with obstacles. Experimental simulation results show that using the PSO algorithm to solve the obstacle-free problem and then using the A* algorithm to correct the path obstructed by obstacles in the obstacle scenario, the agricultural UAV crop spraying trajectory planning based on the PSO-A* algorithm is real and effective. This research can provide theoretical basis for agricultural plant protection and solve the premise of autonomous operation of UAVs.

647-656

Authors: Ştefania-Adriana HOŢEI, Cristina Ioana MARGHESCU, Rodica Cristina NEGROIU, Andrei DRUMEA

Climate change is having a strong impact on agriculture, and those most affected are small farmers and those practicing subsistence agriculture. Better management of resources is also needed in this context. IoT monitoring tools enable real-time monitoring of crops to make decisions, for example, regarding irrigation. For them to be used by smallholder and subsistence farmers, the system must be inexpensive and easy to use, preferably with interfaces with which the user is already familiar. We wanted to develop a low-cost system with commercially available components and a familiar interface. Since most households in Romania have Internet access or a cell phone with data, data transfer via WiFi was chosen, and Google Sheets was used for data management. For power supply, different methods were tested, from batteries to autonomous systems with solar cells and supercapacitors. The system has successfully passed the first tests and is now being implemented.

667-680

Authors: Petru CARDEI, Nicolae CONSTANTIN, Vergil MURARU, Catalin PERSU, Raluca SFIRU, Daniel LATEŞ

The investigation on the unpredictability of the distribution of traction resistance forces on the working bodies of a specific type of MCLS complex cultivator is presented in the paper. The validation of the random character of the force that loads the active bodies is used to indicate the mathematical model that must be followed for the research of the soil processing system. Also, the research results elucidate some hypotheses issued in the conception and design of the machine: the more intense load for the working bodies from the lines of working bodies located immediately after the tractor, the existence of working bodies that are constantly more intensively requested and the causes. According to the literature, it is to be assumed that the forces that demand the working bodies, the supports, and the machine frame have a random nature. The conclusions of the descriptive, inferential statistical study (which do not quantify the random intensity) are explained together with the results. The experimental loads are compared to some of the most random strings to produce a quantitative estimate of the random intensity. As a result, processes that use random functions and the entirety of their approach are recommended in mathematical modelling for further research

690-702

Authors: Puhang LI, Xinyue ZHANG, Hao ZHANG, Zeyu WANG, Shiwei WEN, Jun CHEN

Aiming at the problems of high damage rate and loss rate of the existing safflower harvesting equipment, this study designed a rotary cutting safflower harvesting end effector by combining the growth characteristics and mechanical properties. Through force analysis of the cutting tool, the key factors, which affects the harvesting performance, were clarified to be the blade inclination and the knife shaft speed. The Fluent software was used to analyze the flow field of the harvesting chamber, which aims to determine the appropriate wind speed. To improve the working performance of the rotary cutting safflower harvesting end effector, a three-factor, three-level orthogonal test was carried out with the blade inclination, knife shaft speed and wind speed as the influencing factors, and with the recovery rate, damage rate and loss rate as the response indexes. A regression model for the three-factor interaction was developed and optimized based on the results of the Box-Behnken test. The optimal parameter combination is: the blade inclination is 15°, the knife shaft speed is 1570 r/min, and the wind speed is 6 m/s. A test of the optimization results showed that the recovery rate was 91.47%, the damage rate was 7.51%, and the loss rate was 4.67%. This study can provide theoretical basis and technical reference for the mechanized harvesting of safflower.

713-724

Authors: Weisong ZHAO, Yongsheng CHEN, Weiqiang LIN, Zhenwei WANG, Qimin GAO, Hu XIE, Biao MA, Mingjiang CHEN, Jingjing FU

In order to study the mechanical properties of compression and stress relaxation of manure under drainage conditions, the experiment was carried out with cattle manure as the object, and the constitutive models were improved to describe the stress-strain curves of compression and stress relaxation. The defined constitutive model was determined by parameter identification, and the influence laws of moisture content and filling mass on the compression and relaxation process were investigated. The results show that the improved Nishihara model and the five-component generalized Maxwell model can better describe the compression and stress relaxation properties of cattle manure, and the coefficients of determination of the parameters of the fitted intrinsic model are all greater than 0.9, with high fitting accuracy. The compression process was divided into three stages: exhaust, drainage, and viscoelastic-plastic deformation. The stress decay rate tended to change quickly and then slowly, and there was a negative correlation between the compressed mass, moisture content, and stress decay rate. Duncan's mean comparisons revealed that the differences in elastic modulus between different moisture content / compressed mass groups in the parameters of the cattle manure compression principal model were all significant (P<0.05). The differences in elastic modulus and coefficient of viscous attenuation between different moisture content groups in the parameters of the stress relaxation model were all significant. The study's results can provide the theoretical basis for the study and simulation of CM's compression and dewatering mechanism and provide support for the solid-liquid separator for livestock and poultry manure.

734-744

Authors: Bai-wei WANG, Gang CHE, Lin WAN, Nai-chen ZHAO, Zhan-nan GUAN

Aiming at the problem of poor uniformity and stability of fertilizer discharge caused by the operation of the fertilizer discharger in the variable fertilization operation of rice. Combined with the agronomic requirements of deep fertilization on the northeast side, an impeller type variable side deep fertilizer was designed. According to the change of the prescription map, change the adjustment factors to achieve reasonable fertilization. Based on EDEM simulation, using the fertilizer discharge stability and uniformity coefficient of variation as indicators, under different impeller blades, different impeller speeds and different fertilizer discharge port angles, a secondary orthogonal rotation combination test was carried out, using Design-Expert. V8.0.6.1 is analyzed and tested, the regression equation and the response surface diagram are obtained, the interaction between the influencing factors is analyzed, and the best combination is determined. It is concluded that the stability and uniformity coefficient of variation of fertilizer discharge have reached the quality evaluation index of fertilization machinery According to technical specifications, the coefficient of variation of stability is 0.67%~2.85%, and the coefficient of variation of uniformity is 2.7%~16.4%. When the number of blades is 6, the fan angle of the fertilizer outlet is 35.7°, and the impeller speed is 18.85 r·min-1, the minimum variation coefficient of stability is 0.67%, and the minimum variation coefficient of uniformity is 2.1%. The bench test results are basically consistent with the optimal combination of simulation, and meet the design requirements.

755-764

Authors: Junhui SUN, Jinliang GONG, Yanfei ZHANG

In order to solve the problem of poor flexibility of existing picking manipulators, a picking manipulator with a wrist joint has been designed, the wrist is capable of rotating 45° forward and backward around the x and y axes. Firstly, ANSYS was used to simulate the performance of different hoses under different conditions, and finally a 4*6 mm PVC hose was selected to replace the internal cardan joint as the transmission component. Secondly, the wrist structure was optimised using genetic algorithm to reduce the tendon rope variation differences to 0.31 mm and 0.24 mm. Finally, the results of orchard picking experiments indicate that the end-effector rotation of 720° can ensure that the fruit stalks can be unscrewed, the time required to complete the picking is 1.6 s, and the overall picking success rate was 100%. After 9 days of placing the harvested fruit, both the flesh and skin are intact, indicating that the manipulators can complete the non-destructive picking operation.

776-784

Authors: Christos I. DIMITRIADIS, Dimitrios KATERIS, Panagiotis XYRADAKIS, Aspasia GIALAMA, Theodoros GIALAMAS

Operator fatigue during work with agricultural machinery is a significant factor contributing to fatal accidents in Greece. Workers operating agricultural machinery, especially those working with tractors and off-road machines, constitute one of the most hazard-prone groups due to mechanical vibrations transmitted from the ground to the operators’ seats. Operators of tractors and off-road machines are exposed to intense mechanical vibrations, underscoring the importance of cumulatively calculating permitted working hours. This work presents a study that was conducted at the Laboratory of Safety and Ergonomics of Agricultural Machinery, Department of Agriculture – Agrotechnology, Faculty of Agricultural Sciences, University of Thessaly, in order to evaluate the vibrations generated when operators work with agricultural tractors and off-road machinery. The results of the study showed that the highest levels of vibration occurred during disc harrowing operation, particularly when the disc harrow moved vertically or at an angle of 30° to the ploughing direction. For seed bed preparation, it is recommended to use tractors equipped with a suspension system for the operator's cabin and a seat with an adjustable range of perceived vibration. Additionally, to prevent fatigue or health problems for tractor operators, it is advisable to limit permitted working hours to fewer than 8 hours per day.

798-807

Authors: Iulian VOICEA, Petru CÂRDEI, Vlad-Nicolae ARSENOAIA, Nicoleta UNGUREANU, Florin NENCIU, Nicoleta VANGHELE

The paper proposes a statistical method for assessing the impact of multiple nutritional recipes on fish growth, raised in polyculture systems, a useful tool in selecting diets within small and medium-sized farms. After designing an experimental installation that produces pelletized feed, the study investigated the associations dependent on the feeder composition for three fish species involved in the experiment (Cyprinus carpio, Hypophthalmichthys nobilis and Carassius carassius). The fish relative mass and size variations have been used as performance parameters. The authors also issued hypotheses on the relations created between the studied species and determined the Feed Conversion Ratio.

818-833

Authors: Volodymyr BULGAKOV, Hryhorij KALETNІK, Oleksandra TROKHANIAK, Svitlana LUTKOVSKA, Mykola KLENDII, Semjons IVANOVS, Lucretia POPA, Vitalii YAROPUD

Restoration of the soil fertility is an important task for scientists and practitioners. Based on the constructed mathematical model of the surface of a screw-type working body, rotating around a fixed horizontal axis, there are determined the work and power of penetration of the screw-type working body into the soil, loosening the soil and overcoming the soil friction. It has been established that the cutting power is proportional to the square root of deepening of the working body (а1/2), and the radius of the working body (R1/2) is directly proportional to the speed of the unit V. On the basis of a complex of experimental studies, regression dependencies were derived to determine the traction resistance when cultivating the soil with a harrow, equipped with screw-type working bodies. It has been found that the dominant impact upon the value of the traction resistance Рх is exerted by the depth of tillage h, then by the angle of attack β of the battery of the screw-type working bodies, but the least impact is made by the change in the speed of the harrow V. The difference between the calculated and the experimental values of the traction resistance ranges from 9.6...11.2%.

843-856

Authors: Valentin VLĂDUŢ, Sorin-Ștefan BIRIŞ, Gigel PARASCHIV, Nicoleta UNGUREANU, Sorin Tiberiu BUNGESCU, Iulian VOICEA, Dan CUJBESCU, Iuliana GĂGEANU, Evelin LAZA, Lorena-Diana POPA, Gheorghe MATEI, Atanas ATANASOV

Vibrations are part of the category of dynamic phenomena and are manifested in some medium as a consequence of an external excitation in the form of oscillations. These oscillations have negative effects on the medium in which they manifest. In the particular case where the medium is represented by the human body, the negative effects are felt at the level of its health, and the consequences are sometimes irreversible. In this context, it is necessary to study and know the effects that vibrations have on the human body. The main purpose of researches carried out in this field is to establish the limit up to which man can work in medium that generate vibrations, without the vibrations affecting his state of health.

865-881

Authors: Guoli HAN, Shuming MA

In today's increasingly accelerating globalization, environmental protection and sustainable development have become the focus of common concern for all countries. Public environmental awareness, that is, the public's understanding and attitude towards environmental issues, has a significant impact on environmental protection work. Meanwhile, with the rise of green product trade, the market trading of green products is becoming increasingly active. As one of the means to regulate the relationship between public environmental awareness and green product trade, the role of policies and legal texts is increasingly prominent. This article will explore the relationship between public environmental awareness and green product trade and analyze the regulatory role of policies and legal texts in it. This article explores the impact of trade and environmental policies on the financial system through computer software. It constructs a theoretical hypothesis model to explore the moderating effect of policy and legal texts on the relationship between public emotional perception of environmental policies and green product trade. After empirical testing, all research hypotheses in this study have been supported. The results showed that at a test level of 0.01, consumers' perception of green efficacy, perceived green responsibility, green purchasing behavior, emotional arousal, and moderate values were significantly positively correlated. Among them, the R-value of perceived green efficiency and green purchasing behavior is 0.701, and the R-value of perceived green responsibility and green purchasing behavior is 0.638, indicating the degree of correlation between perceived green efficiency, perceived green responsibility, and green purchasing behavior. Green purchasing behavior is highly correlated. The conclusion indicates that the government has further increased export subsidies for the clean industry, implemented differentiated environmental tax policies, and emphasized the coordinated use of procedures, promoting the development of the clean industry and the upgrading of industrial structure.

891-903

Authors: Vasilica ȘTEFAN, Radu CIUPARCĂ, Emil TUDOR, Mihai MATACHE, Ionuț VASILE, Ion Cătălin SBURLAN, Ana ZAICA

The article presents the results obtained from experimental research conducted with an electric equipment (a watercraft) for harvesting aquatic biomass (reed, cattail, water lily, etc.), remote controlled, symbolized as ERBA. This equipment was designed and built in Romania by researchers from INMA Bucharest and ICPE-CA, at the level of experimental model. The purpose of this equipment is to develop a national system of machines for cleaning lakes, navigable canals, and specific areas of the Danube Delta Biosphere Reserve from excess biomass that needs to be removed for the proper functioning of aquatic ecosystems. The harvested biomass is used as raw material for the production of liquid and gaseous fuels, as well as biofertilizers, which can be utilized as inputs in the bioeconomy. The phenological characteristics of the harvested biomass, the structural and functional characteristics of the vessel, the laboratory experimental records, the nautical indices, the exploitation indices, and the energy consumption were measured under different working conditions and regimes, and with different types of biomass.