To address the issue of the single-crop adaptability of current head-forming leafy vegetable harvesters in China-which limits their ability to harvest multiple vegetable varieties-a universal cabbage-Chinese cabbage harvesting platform was designed. This design was based on the statistical analysis of the physical and planting parameters of major cabbage and Chinese cabbage varieties in Jiangsu and Zhejiang provinces. The harvesting platform adopts a modular design, enabling the harvesting of both Chinese cabbage and cabbage by replacing specific components and adjusting relevant parameters. Through the theoretical analysis of key components, the specific parameters of each part were determined, and a soil-trough harvesting test was conducted. The results of the Chinese cabbage harvesting test showed that at a forward speed of 1 kmh-1 and a conveyor belt speed of 60 RPM, the platform achieved optimal performance, with an extraction success rate of 86.7%, a clamping and conveying success rate of 92.3%, and an operational damage rate of 6.7%. The cabbage soil-trough harvesting test results indicated that when the extraction roller speed was 100 RPM, the conveyor belt speed was 60 RPM, and the forward speed was 1 kmh-1, the extraction and feeding success rate reached 93.3%, the conveying success rate was 100%, and the operational loss rate was 6.7%, representing the best overall performance. This study provides theoretical support and references for the design of universal harvesters for head-forming leafy vegetables.

To address problems encountered in current potato harvesting machines in hilly and mountainous areas, such as potato damage, poor adaptability, low operational efficiency, and the inability of traditional harvesters to meet the requirements in these areas, a new potato harvester equipped with excavation and a multi-stage separation conveyor was developed by using design and simulation programs as an innovative way to identify the best operating factors. SolidWorks Software was used to design an excavation and a multi-stage separation conveyor. ANSYS Workbench machine static structure analyzed stress, strain, and deformation. The working process of soil and tuber separation was tested and kinematically analyzed by EDEM-RecurDyn and a 5F01M camera. A field experiment was also conducted on the machine under several factors: working speed (W), excavation depth (D), vibration intensity level (V), and conveyor inclination angle (N). The quadratic regression orthogonal rotating combination experiment tested four factors with five levels. The results of the non-load experiment showed that the lowest ratio of impurities was at the linear speed level (Q3, S5, O3) for the first and second separation conveyor and the side conveyor, respectively. The results of the field experiment showed that the optimal parameters were the working speed of 1.05 m/s, the digging depth of 180 mm, and the vibration force II inclination angle on the screen surface of 22 degrees, which gave the highest potato lifting rate of 98.8%, and the bruising rate was 1.37%. The damage rate was 1.43%, superior to national industry standards. With its exceptional performance, the machine can effectively meet and solve the challenges of harvesting requirements, making it a valuable tool for the industry.

Given the significant damage rate observed during the transportation of current garlic combine harvesters in China, this study aims to design a new garlic combine harvester capable of achieving minimal harvest losses. The designed machine can simultaneously complete operations for garlic digging, clamping transport, seedling-bulb separation, soil cleaning, and fruit collection across two rows. Through the use of theoretical analysis and calculation of garlic harvesting operations, the key parameters of soil-breaking device, clamping transport device, length-limiting cutting device, and soil cleaning conveyor were determined. The BoxBehnken test technique was utilized within Design-Expert software, and orthogonal experiments were conducted with the unit's forward speed, digging depth, and soil-breaking angle as test factors, and the stem cutting rate and bulb damage rate as test indices. The test results showed that when the unit's forward speed, digging depth, and soil-breaking angle were 0.49 m/s, 100 mm, and 20 degrees, respectively, the working parameter combination was the best, and the rate of stem cutting and damage were 95.71% and 3.10%, respectively. The findings from the field experiment and optimization aligned closely. This study can provide reference for the development of mechanized garlic harvesting.

Aiming to address the problems of poor separation of peanuts and soil and severe damage of pods during peanut harvesting in saline soil, a peanut digging and harvesting machine was designed using extrusion shaking vibration and roller extrusion. Theoretical calculations determined the structural parameters of critical components. The law of motion of the seedling soil assemblage at the stage of separation and transportation was derived by analyzing the kinematic properties. The soil extrusion vibration crushing dispersion and sieving process was analyzed, and the factors affecting soil crushing and separation were determined by establishing the extrusion collision model. One-way and orthogonal tests used soil content, breakage, and loss rates as test indicators. The orthogonal test showed that the working parameters were as follows: working speed was 0.889 m/s, the inclination angle was 21.5 degrees, the working line speed of the sieve surface was 2.00 m/s and the roller gap of the roller squeezing device was 37 mm, the peanut harvesting rate of soil content was 1.36%, the breakage rate was 0.78%, and the loss rate was 1.15%. The paper references developing a peanut harvester for clay-heavy soil with soil separation performance improvement.

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.

In China's Yangtze River and Yellow River basin cotton-growing regions, the complex terrain, scattered planting areas, and poor adaptability of the existing machinery have led to a mechanized cotton harvesting rate of less than 10%. To address this issue, we designed a crawler chassis for a brush-roller cotton harvester. It is specifically tailored to meet the 76 cm row spacing agronomic requirement. We also conducted a theoretical analysis of the power transmission system for the crawler chassis. Initially, we considered the terrain characteristics of China's inland cotton-growing regions and the current cotton agronomy practices. Based on these, we selected and designed the power system and chassis; then, a finite element static analysis was carried out on the chassis frame to ensure safety during operation; finally, field tests on the harvester's operability, stability, and speed were carried out. The results show that the inverted trapezoidal crawler walking device, combined with a hydraulic continuously variable transmission and rear-drive design, enhances the crawler's passability. The crawler parameters included a ground contact length of 1650 mm, a maximum ground clearance of 270 mm, a maximum operating speed of 6.1 km/h, and an actual turning radius of 2300 mm. The maximum deformation of the frame was 2.198 mm, the deformation of the walking chassis was 1.0716 mm, the maximum equivalent stress was 216.96 MPa, and the average equivalent stress of the entire frame was 5.6356 MPa, which complies with the physical properties of the selected material, Q235. The designed cotton harvester crawler chassis features stable straight-line and steering performance. The vehicle's speed can be adjusted based on the complexity of the terrain, with timely steering responses, minimal compaction on cotton, and reduced soil damage, meeting the requirements for mechanized harvesting in China's inland small plots.

Cassava is one of the world's top three tuber crops, and its harvesting mechanization level is low. Digging- pulling cassava harvester is the main research direction of cassava harvesters. However, the soil-loosening components of the existing digging-pulling harvesters have poor loosening effect, high tuber damage rate, and large pulling force of cassava tubers after loosening. The two-sided loosening shovel that digs and loosens the soil on both sides of the tubers has low working resistance and is not easy to damage the tubers, but there are few reports on the impact of its operating performance. Therefore, this study focuses on three common types of two-sided soil-loosening shovels: the offset-wing shovel (OWS), L shovel (LS), and double-wing shovel (DWS). A two-factor, three-level orthogonal experiment is conducted, taking tillage depth (h) and shovel distance (b) as variables, then range analysis and factor impact analysis are carried out. Finally, through comprehensive comparison and optimization, a shovel type with best operational effects and its optimal working conditions are identified. The results show the LS demonstrated optimal performance when the breakage rate and pulling force were minimized. At the optimal combination of h of 0.25 m and b of 0.6 m, the LS has a breakage rate of 7.576% and a pulling force of 291.608 N. This study can provide basis for optimizing the design of loosening parts of digging-pulling cassava harvester.

The limited separation efficiency of potato-soil separation equipment in the southern potato planting areas is attributed to the high viscosity of the soil. To enhance the performance of the lifting chain separation device, a concave bar was designed. Structural parameters influencing the efficiency of potato-soil separation by bars were determined through kinetic analysis during the separation and transportation of potato-soil mixtures. Both a potato simulation model and a sticky soil simulation model were developed. Simulation tests indicated that the concave bar outperforms the straight bar in separation efficiency. Key factors investigated include the angle of the concave side, the width of the concave bar, the depth of the concave bar, and the installation angle. Orthogonal simulations were conducted using separation efficiency and the maximum force on potatoes as evaluation metrics. The results demonstrated that with a concave side angle of 15 degrees, a concave bar width of 450 mm, a concave bar depth of 60 mm, and an installation angle of 30 degrees, the separation efficiency of the potato-soil mixture reached 79.7%, with a maximum force on potatoes of 35.218 N, achieving the highest separation efficiency. Based on these results, test devices were constructed, and field tests were performed. The field test results showed a damage rate of 1.58%, a potato epidermal injury rate of 1.03%, and a loss rate of 2.87%. These results comply with national standards and validate the reliability of the simulation findings.

At present, the potato's mechanized harvesting rate in hilly and mountainous areas is very low. The reasons for this are that in heavy soil, the separation of potato rhizomes from soil or vines is not sufficient, harvesting machinery is seriously damaged by the potato epidermis, and the harvested potato is easily buried in soil, resulting in a missed harvest. In this paper, a two-stage cleaning potato harvester with wave-type and roller-group-type separating mechanisms was designed, and its overall structure and working principle are introduced in detail. The new cleaning mechanism can increase the effective separating length and effective contact area of the potato-soil mixture so as to achieve the purpose of removing clay and heavy soil. The main separator uses a structure that combines offset waves with opposite waves and a staggered arrangement of large-small diameter straight bars. The secondary separator adopts a device combining left-hand and right-hand separating rollers. The discrete element model of the whole machine was established, and the results of the theoretical analysis were verified by simulation. The key factors affecting the harvest quality were analyzed by variance analysis and response surface analysis, and the field experiment was carried out with the rate of clean potatoes, damaged potatoes, and peeled potatoes harvested as the indexes. The field experiments showed that the machine achieved a rate of photos on or out of the earth of 98.87%, a damaged potato rate of 0.91%, and a peeled potato rate of 1.13%. The research results provide theoretical support and a technical reference for the design and optimization of potato harvesters, as well as the improvement of the potato-soil separating efficiency and harvest quality.

Traditional methods for harvesting medicinal materials with long roots, like Astragalus membranaceus, require extensive soil excavation, leading to problems like inefficient soil separation, low stemming rates, and blockages in conveyor chains. To address these challenges, this study introduces a prototype machine capable of digging, separating soil, crushing soil, and collecting the medicinal materials in one continuous process. The paper focuses on the machine's design and working principle, with theoretical analysis and calculations for key components like the digging shovel, multi-stage conveyor, and soil-crushing device. Specific structural parameters were determined, and the screening efficiency of the roller screen was analyzed using EDEM 2020 software, comparing scenarios with and without rollers. A motion model for the medicinal materials during conveyance was established, allowing for the determination of optimal linear velocity and mounting angle for the conveyor. Additionally, a motion model for the second-stage conveyor chain and rear soil-crushing device was used to optimize their placement, ensuring efficient soil crushing without affecting the thrown Astragalus. Compared to traditional Chinese medicine diggers, this machine boasts superior resistance reduction and soil-crushing capabilities. Compared with traditional harvesters, the drag-reducing and soil-crushing device of this machine is more efficient, reducing the damage to Astragalus during the harvesting process, reducing the labor intensity of farmers, and improving the quality and efficiency of Astragalus harvesting. Field experiments have shown that when the operating speed of the prototype is 1.0 m/s and the roller-screen speed is 130 similar to 150 rpm, the operating performance is optimal, and comparative experiments can be conducted under the optimal parameters. From the experimental results, it can be seen that the improved equipment has increased the bright-stem rate by about 4%, the digging and loosening rate by 97.42%, and the damage rate by 2.44%. The equipment design meets the overall design requirements, and all experimental indicators meet national and industry standards. This provides a reference for the optimization and improvement of the soil-crushing device and the structure of the Astragalus membranaceus harvester.