Search Results (15)

China boasts abundant straw resources but grapples with notable challenges in straw processing: returning straw to fields can lead to soil compaction and aggravated pests/diseases, while baled straw for off-field storage and transportation tends to scatter. Additionally, domestic netting technology for square bales remains underdeveloped, and imported equipment is ill-suited for small-scale farmers. To tackle these issues, this study developed an integrated straw baling and netting machine by modifying the 9YFSG-2.2 square straw baler. It integrates a conveying mechanism, an offset crank–connecting rod compression mechanism (300 mm crank, 885 mm connecting rod), a two-stage gear-driven net-wrapping mechanism (with hollowed-out large gears for weight reduction), and a sensor-controlled net-cutting device, forming a complete workflow of “straw pick-up–shredding–conveying–compaction–net wrapping–net cutting”. Via coupled simulation using RecurDyn 2019, EDEM 2020, and ANSYS Workbench 2018, straw particles were modeled as 28-mm-long segments (composed of three 7 mm spheres). Simulations showed straw compaction in 0.48 s, with the compression chamber and plate having equivalent stresses of 0.2767 MPa and 173.44 MPa and maximum deformations of 0.0012 mm and 0.66 mm—both well below structural steel’s yield strength. Field tests in Xinxiang, Henan (straw moisture 30.03%), yielded results exceeding standards: 99.4% bale formation rate, 96% regular bale rate, 93% drop resistance rate, 170 kg/m³ bale density, and 12 s per bale efficiency. Controlling netting time further boosted efficiency and reduced consumption, successfully realizing integrated straw baling and netting. Full article

This paper aims to address the problem of the low success rate of seedling picking and throwing, and the high damage rate of pot seedling, caused by the unclear interaction and parameter mismatch between the seedling picking end effector and the pot seedling during the seedling picking and throwing process of automatic transplanters. An EDEM–RecurDyn coupled simulation was conducted, through which the disturbance of substrate particles in the bowl body during the inserting, extracting, and transporting processes by the seedling picking end effector was visualized and analyzed. The force and motion responses of the particles during their interaction with the seedling picking end effector were explored, and the working parameters of the seedling picking end effector were optimized. A seedling picking end effector using two fingers and four needles is taken as the research object, a kinematic mathematical model of the seedling picking end effector is established, and the dimensional parameters of each component of the end effector are determined. Physical characteristic tests are conducted on Shanghai bok choy pot seedlings to obtain relevant parameters. A discrete element model of the pot seedling is established in EDEM 2022 software, and a virtual prototype model of the seedling picking end effector is established in Recurdyn 2024 software. Through EDEM-Recurdyn coupled simulation, the force and movement of the substrate particles in the bowl body during the inserting, extracting, and transporting processes of the seedling picking end effector under different operating parameters were explored, providing a theoretical basis for optimizing the working parameters of the end effector. The inserting and extracting velocity, transporting velocity, and inserting depth of the seedling picking end effector were used as experimental factors, and the success rate of seedling picking and throwing, and the loss rate of substrate, were used as evaluation indicators; single-factor tests and three-factor, three-level Box–Behnken bench tests were conducted. Variance analysis, response surface methodology, and multi-objective optimization were performed using Design-Expert 13 software to obtain the optimal parameter combination: when the inserting and extracting velocity was 228 mm/s, the transporting velocity was 264 mm/s, the inserting depth was 37 mm, the success rate of seedling picking and throwing was 97.48%, and the loss rate of substrate was 2.12%. A verification experiment was conducted on the bench, and the success rate of seedling picking and throwing was 97.35%, and the loss rate of substrate was 2.34%, which was largely consistent with the optimized results, thereby confirming the rationality of the established model and optimized parameters. Field trial showed the success rate of seedling picking and throwing was 97.04%, and the loss rate of substrate was 2.41%. The error between the success rate of seedling picking and throwing and the optimized result was 0.45%, indicating that the seedling picking end effector has strong anti-interference ability, and verifying the feasibility and practicality of the established model and optimized parameters. Full article

This study addresses the challenges encountered in mechanized agricultural fields, particularly the soil disruption associated with conventional horizontal rotary straw cleaning equipment. To mitigate the inefficiency of straw cleaning observed in the current vertical rotary apparatus, this study introduces a vertical rotary fixed-angle straw cleaning device. The essential conditions for establishing the cutter tooth angle were identified through theoretical analysis. Analyzing the kinematics of the cutter tooth to direct the movement of the straw, we determined that the deflection angle of the cutter tooth group (DA) is a critical parameter for enhancing the effectiveness of straw cleaning. A multiphase interaction model encompassing soil, straw, and machinery components was developed utilizing a coupled simulation approach with RecurDyn and EDEM software. The Box–Behnken response surface methodology was employed to systematically investigate the interaction effects of three critical parameters on both the straw cleaning rate and the soil disturbance rate: operation speed (OS), rotation speed of the straw cleaning rotary table (RS), and the DA. For optimization experiments where the OS is set to 2.4 m/s, RS is 400 r/min, and DA is 48°, the straw cleaning rate reaches 94.1% and the soil disturbance rate is 27.2%. This device can efficiently create a localized clean seeding belt for no-till planters without significantly damaging the soil structure, providing an innovative solution for the development of low-disturbance, high-efficiency conservation tillage equipment. Full article

Existing force-measuring devices lack versatility in studying the dynamic coupling process between the seedling-picking device and the plug seedling pot during automatic transplanting. This research developed a universal force-measuring device featuring a centrally symmetrical clamping needle layout and a simultaneous insertion and clamping mechanism. The force-measuring device enables the flexible adjustment of the number of clamping needles (2/3/4 needles) via a modular structure. It can also modify the insertion depth and angle of the clamping needles to accommodate three specifications of plug seedlings, namely 50-hole, 72-hole, and 128-hole plug seedlings. A real-time monitoring system with dual pull-pressure sensors is integrated to precisely acquire the dynamic response curves of the clamping force (F_J) and the disengaging force (F_N) of the plug seedling pot during the seedling-picking process. Taking water spinach plug seedlings as the research object and combining with EDEM-RecurDyn coupling simulation, the interaction mechanism between the clamping needle and the plug seedling pot was elucidated. The performance of the force-measuring device was verified through systematic force-measuring experiments. The main research findings are as follows: The force-measuring device designed in this study can successfully obtain the mechanical characteristic curve of the relevant seedling plug pot throughout the automatic seedling-picking process. The simulation results show high consistency with the experimental results, indicating that the force-measuring device can effectively reveal the dynamic coupling process between the seedling-picking device and the plug seedling pot. The verification experiment demonstrates that the force-measuring device can effectively quantify the mechanical properties of the of plug seedling pots under different plug seedlings specifications and different clamping needles configurations. Reducing the hole size and increasing the number of clamping needles can effectively decrease the peak value of the disengaging force (F_Nmax). The peak clamping force (F_Jmax) is approximately inversely proportional to the needle number, with the four-needle layout providing the most uniform force distribution. The force-measuring device developed in this study is functional, applicable, and versatile, offering a general force-measuring tool and a theoretical foundation for optimal seedling-picking device design. Full article

To mitigate the high stubble rates (root residue rates) and plant damage associated with the current mechanized harvesting of Shanghai Green (Brassica rapa subsp. chinensis), this study developed and optimized a novel soil loosening and root lifting device. A theoretical dynamic model was first established to analyze the device’s operational principles. Subsequently, a coupled multi-body dynamics and discrete element method (RecurDyn-EDEM) model was established to simulate the complex interactions between the device, soil, and plant roots. Response surface methodology was employed to optimize key operational parameters: walking speed, loosening depth, and vibration frequency. The simulation-based optimization was validated by field tests. The optimal parameters were identified as a walking speed of 0.137 m/s, a loosening depth of 34.5 mm, and a vibration frequency of 1.34 Hz, under which the Shanghai Green pulling force was 35.41 N, yielding optimal extraction performance. Field tests conducted under these optimal conditions demonstrated excellent performance, achieving a qualified plant posture rate of 87.5% and a low damage rate of 7.5%. This research provides a robust design and validated operational parameters, offering significant technical support for the development of low-loss harvesting equipment for leafy vegetables. Full article

To address the inefficiency and high cost of manual potato pickup in segmented harvesting, a dual-disc potato pickup and harvesting device was designed. The device utilizes counter-rotating dual discs to gather and preliminarily lift the potato–soil mixture, and combines it with an elevator chain to achieve potato–soil separation and transportation. Based on Hertz’s collision theory, the impact of disc rotational speed on potato damage was analyzed, establishing a maximum speed limit (≤62.56 r/min). Through kinematic analysis, the disc inclination angle (12–24°) and operational parameters were optimized. Through coupled EDEM-RecurDyn simulations and Box–Behnken experimental design, the optimal parameter combination was determined with the potato loss rate and potato damage rate as evaluation indices: disc rotational speed of 50 r/min, disc inclination angle of 16°, and machine forward speed of 0.6 m/s. Field validation tests revealed that the potato loss rate and potato damage rate were 1.53% and 2.45%, respectively, meeting the requirements of the DB64/T 1795-2021 standard. The research findings demonstrate that this device can efficiently replace manual potato picking, providing a reliable solution for the mechanized harvesting of potatoes. Full article

In view of the problems of low work efficiency and high operating costs caused by manual harvesting of Chinese cabbage in China, in this study, a Chinese cabbage harvester with agronomic integrity was designed. The harvester is mainly composed of a crawler chassis, a drawing device, a flexible clamping device, a cutting device, and a horizontal delivery device. Firstly, physical properties of Chinese cabbage such as diameter, plant height, weight, and drawing rate of Chinese cabbage were measured and analyzed to provide necessary basic data for the design of the harvester. Secondly, simulation tests were conducted on the Chinese cabbage harvesting process; a 3D model of Chinese cabbage using SolidWorks 2022 was established and filled with particles using the three-layer stacking method. At the same time, SolidWorks was applied to simplify the model of the Chinese cabbage harvester. The belt of the machine model was set as a flexible body through RecurDyn 2023 software and coupled with EDEM 2022 for simulation analysis. Based on single factor tests, the BBD model was applied to conduct multi-factor response surface analysis on the above factor levels. The optimal working conditions of the harvester were obtained as follows: the rotating speed of the cutting device was 207.85 r/min, the rotating speed of the flexible clamping conveyor belt was 165.51 r/min, the rotating speed of the drawing device was 102.38 r/min, and the machine walking speed was 1.37 km/h. The qualified rate of Chinese cabbage harvesting was the highest, achieving a maximum theoretical value of 97.91%. Field validation tests were conducted on the designed Chinese cabbage harvester. Based on the actual operating conditions of the Chinese cabbage harvester and the simulated operating parameters, the optimal parameter combination was finally determined as follows: rotating speed of the root cutting device was 200 r/min, rotating speed of the flexible clamping conveyor belt was 160 r/min, rotating speed of the drawing device was 100 r/min, and machine walking speed was 1.4 km/h, respectively. Through field verification tests, the highest qualified rate of Chinese cabbage harvesting reached 93.19%, showing a good harvesting effect, which approximates the simulated optimal qualified rate of 97.91%, meeting the mechanized harvesting demand of Chinese cabbage. This study provides reference to the further design and development of Chinese cabbage harvesters in the future. Full article

This study addresses the issues of high operating resistance, incomplete separation in ascending transport chains, and significant wear and tear in existing licorice harvesters. A new licorice harvester has been designed that incorporates a lift chain conveyor separation device, enabling excavation, separation, collection, and centralized stacking to be completed in a single operation. The paper describes the harvester’s overall structure and provides detailed analyses and designs of its key components, including the digging shovel, roller screen, conveying and separating screens, and soil-crushing roller. Multi-body dynamics (MBD) and discrete element models (DEM) for licorice and soil were developed, and the entire harvesting process was simulated using the coupled DEM–MBD method to analyze the trajectory and speed of the licorice. Field tests confirmed that the conveyor separation screen operates smoothly, effectively separates licorice rhizomes from soil, and minimizes damage to the licorice. Field test results show a net digging rate of 96.2%, a damage rate of 4.3%, and an average digging depth of 580 mm. The operational indexes meet the standards for harvesting root and stem Chinese herbal medicines. The machine operates stably and exhibits exceptional conveying and separating effects, demonstrating its suitability for mechanized harvesting of root and stem herbs. Full article

The purpose of this paper is the design of a potato drip irrigation tape recycling machine that would not require manual assistance or suffer from broken tapes. To clarify the recycling performance of the new potato drip irrigation tape recycling machine under different working parameters, a single-factor performance experiment was conducted. To investigate the reasons for variations in the performance indexes of the machine under different operating parameters, RecurDyn-EDEM coupled simulation experiments were carried out, with the peak height of soil and the maximum bending angle of the drip irrigation tape during the recycling process as the experimental indexes. To determine the optimal working parameter combinations and to clarify the effects of the interaction of various factors on the performance indexes, a response surface experiment was conducted. Following this, an analysis of variance was performed, and a mathematical regression model was established based on the experimental results. The findings revealed that a machine forward speed of 2.4 km/h, a shovel angle of 12°, and a conveyor sprocket speed of 270 r/min resulted in a drip irrigation tape recovery rate of 95.2%, meeting the relevant standards for drip irrigation tape recycling operations. Full article

The planting mechanism of existing transplanters cannot meet the agronomic requirements of planting densely planted vegetables with multiple rows, small plant spacing, and small row spacing. In order to solve this current problem, an eight-row duckbill planting mechanism driven by a motor and a cylinder was designed. According to the agronomic guidance and mechanism design requirements for transplanting densely planted vegetable seedlings, this paper analyzes the working principle of the planting mechanism, establishes its kinematic theoretical model, and determines the structural parameters of the driving device and opening and closing device in the planting mechanism. Aimed at the problem of large planting resistance when eight-row planting end effectors of the planting mechanism are planting at the same time, based on the existing research, three duckbill planting end effectors with double incisions, four incisions, and conical structures were selected, and the planting process was simulated using an EDEM 2022-RecurDyn 2024 coupling simulation. The single-factor analysis method and the interactive factor Box–Behnken response surface analysis method were used. It is concluded that the duckbill end effector with double incisions has the smallest planting resistance, and the rationality of the mechanism design is preliminarily verified. A planting resistance measurement platform was built based on the STM32 platform and HX711 module, and a planting resistance test of the duckbill planting end effector was carried out to verify the correctness of the planting mechanism simulation results. The planting mechanism performance test was carried out, and the test results showed that the planting qualification rate of the prototype reached 96.62%, the planting spacing variation coefficient was only 3.55%, and the planting efficiency reached about 7135 plants/h, which met the agronomic requirements of small plant spacing and small row spacing for densely planted vegetables and verified the feasibility and practicality of the planting mechanism. Full article

In view of the challenges faced by cotton dibbler in Xinjiang under high-speed operation, a novel crawler-type delayed hole-forming device has been designed to address the seed throwing and floating issues in high-speed cotton dibbling in Xinjiang, enhancing the duck bill’s performance. This mechanism increases the sowing speed to 6 km/h by extending the duck bill horizontally. Utilizing agronomic principles, the mechanism’s layout and key components were optimized for efficient hole-forming. DEM and multi-body dynamics simulations were employed to analyze the motion, focusing on the fixed the tilt angle of the duck bill (A), the depth of the duck bill hole-forming into the soil (B), and the angle of rotation of the moving duck bill (C) as factors affecting hole dimensions (longitudinal length of hole Y₁ and hole-forming depth of cotton seed hole Y₂). Quadratic regression test using RecurDyn-EDEM coupling identified optimal parameter settings for maximum hole-forming performance. When A was 2.4°, B was 42.4 mm, and C was 30.5°, the performance of the hole-forming was the best. Under the optimal parameter combination, the bench verification test was carried out. The error between the bench verification results and the simulation results is small, indicating that the model has high accuracy. The average opening time of the duck bill at a speed of 6 km/h is 0.45 s, which is much longer than the time required for cotton seeds to fall from the duck bill (0.11 s). It meets the requirements of high-speed cotton planting in China and facilitating advancements high-speed planter technology. Full article

The problem of soil and Chuanxiong tuber congestion on vibrating screens usually exists during the Chuanxiong mechanized harvesting process. To address this problem, the conveyance performance of a crankshaft rocker vibrating screen was studied. By establishing and solving the dynamics and kinematics equations for the crankshaft rocker vibrating mechanism and Chuanxiong soil residue, the acceleration of the vibrating screen and Chuanxiong-soil residue was studied. The sliding speed, motion process, and conveying distance of the Chuanxiong soil residue were also analyzed. The theoretical analysis results indicated that the acceleration of the vibrating screen depends on the rod lengths of the vibrating mechanism and the crank rotational speed and position. The displacement of the Chuanxiong-soil residue along the positive sliding direction in a cycle was more significant than that of the negative sliding direction. The appropriate advancement speed of the harvester was also obtained. The RecurDyn and EDEM coupling simulation was conducted. The simulation results verified the theoretical analysis. In the simulation, the Chuanxiong-soil residue was effectively conveyed. The field tests were conducted to verify the theoretical analysis. The harvester was tested in the field with crank rotational speeds of 0 r/min, 120 r/min, and 240 r/min, and advancement speeds of 0.5 m/s, 1 m/s, 1.5 m/s, and 2 m/s. The results showed that there was no congestion in the screen during the working process when the rotational speed of the crank was 240 r/min, and the advancement speed of the harvester was no faster than 1.5 m/s. When the crank rotational speed was 240 r/min, and the advancement speeds were 0.5 m/s, 1 m/s, and 1.5 m/s, the weights of Chuanxiong and soil on the screen after the test were 71.5 kg, 84.7 kg, and 105.7 kg, respectively. The field tests verified the conveyance performance of the vibrating screen. This study can provide a theoretical reference for designing the crankshaft rocker vibrating mechanism for the rhizome harvesting machine. Full article

This paper addresses the hole-forming process of a duckbilled hole-forming device. Based on a coupled simulation using the multi-body dynamics software RecurDyn and the discrete element software EDEM, the hole-forming mechanism of a duckbilled hole-forming device and the influence of control parameters on the hole-forming performance of the hole-forming device were studied. In this paper, we analyze the direction and speed of soil particles transported under soil disturbance by a hole-forming device through the simulation and study of the hole-forming mechanism of the hole-forming device. By controlling parameters such as the traction angle, forward speed, and mass of the hole-forming device, the influence of the control parameters on the hole-forming trajectory of the duckbilled hole-forming device was investigated. Orthogonal tests determined the optimal combination of control parameters. The results show that the hole-forming process of the hole-forming device mainly comprises squeezing and shearing the soil to form holes, and the hole-forming performance of the hole-forming device was optimal when the traction angle was 17.3°, the forward speed was 1.11 m/s, and the mass of the hole-forming device was 17.9 kg. Full article

The electric cable shovel (ECS) is one of the core pieces of equipment used in open-pit mining, and the prediction of its excavating resistance is the basis and focus of optimization design, such as excavation trajectory planning and structure optimization of the ECS. Aiming to predict the excavating resistance of an ECS, a computer simulation method for the excavating resistance based on EDEM-RecurDyn bidirectional coupling simulation is proposed herein. Taking the China-made WK series ECS as the research object, a 1/30 scale model of the ECS was set up, a prototype model test bench of the ECS was built, and the kinematics solution and force analysis of the excavating process were carried out. According to the actual excavation conditions and excavating process of the ECS, a discrete element model of the material stack and a multibody dynamics model of the ECS prototype were established. The EDEM-RecurDyn bidirectional coupling simulation of the excavating process were realized using interface technology, and the excavating resistance levels under different speed combinations and different material repose angles were simulated and analyzed. In order to verify the accuracy of the simulation results, the feasibility and reliability of the EDEM-RecurDyn bidirectional coupling simulation were verified by physical experiments. The results show that the simulated excavating resistance is basically consistent with the excavating resistance measured in the experiment in terms of peak value and change trend, which verifies the feasibility and reliability of the EDEM-RecurDyn bidirectional coupling simulation to study the excavating resistance of an ECS. Full article

Soybean seeding monomers can realize the process of opening, seed throwing, covering, and compacting when they work. Due to the complexity of their working process, the relevant process cannot be analyzed by the discrete element method (DEM) alone. The DEM coupled with the multi-rigid body dynamics method (MBD) can solve the above problem, and the simulation analysis of the above process is realized by coupling the EDEM software with RecurDyn software. The changes in the position of soybean seed particles before and after covering and compacting are analyzed. The results show that when the working speed of the seeding monomer increases, the distance along the vertical direction of the soybean seed particles after covering gradually increases, and the distance along the horizontal direction gradually decreases. The effect of different working speeds of seeding monomer on the opening situation and the variation in seed particle positions is studied. The results show that the ditch angle gradually decreases as the working speed of the seeding monomer increases. The distribution of seed particle spacing is also analyzed. The above tests are simulated, and the results show a high agreement between the simulation and test results, proving the accuracy of the coupling method. This paper applies the coupling method for the first time to the simulation of the seeding monomer. This method can be applied not only to the analysis of the sowing process of soybean seeding monomers, but also be applied to the analysis of other machinery working processes, such as the tillage process, the sieving process, the planting and harvesting processes of crops, etc. It also deepens the application of the discrete element method in the field of agriculture. Full article