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In order to reduce ground drop loss during mechanical pepper picking and improve the net recovery rate, a drum snap finger picking device was designed. The picking device is mainly composed of a picking drum and auxiliary picking components; the picking finger arrangement was designed biomimetically and its structure and operating parameters were optimized by the DEM (discrete element method). According to the physical and mechanical characteristics of the pepper and the simplified three-dimensional model of the picking device, a virtual simulation model of the pepper-picking device was established using the EDEM software. Through simulation analysis and using the orthogonal test method, the main factors which affect the ground drop loss rate of pepper and their optimal parameter combination values were determined. The simulation results were verified by a pepper-picking field experiment. Orthogonal tests show that, when the picking drum speed ( V ′ ) is 210 rpm, the pepper-feeding speed ( V ″ ) is 1100 m m · s − 1 , the bending angle of each picking spring tooth (C) is 162°, and each group of circumferential fingers has rows, the picking device has a good picking effect. At this time, the ground drop loss rates in both the simulation and field test were 7.50% and 7.85%, respectively, and the drop error was only 4.46%, which was within the allowable range. The design form and parameter optimization simulation method in this paper provide an important reference for the design and optimization of pepper-harvesting machinery. [ABSTRACT FROM AUTHOR]

To improve the declining performance of a full-feed peanut picking device or solve the mechanical failures that occur due to fluctuations in the feeding rate during operation, the 4HLJI-3000 peanut intelligent picking combine harvester, which is a picking device with a self-adaptive adjustment of the working clearance, was developed as the research object in this study. Moreover, the key components, such as the picking roller, concave plate sieve and clearance adjustment mechanism of the concave plate sieve, were designed and analysed. Through the force analysis of the concave plate sieve of the picking device, the mathematical model of the concave plate sieve displacement of the picking device and feeding rate was obtained. The software system for monitoring, storing and analysing the concave plate sieve displacement of the picking device based on EasyBuilder Pro was designed, and the road monitoring test of displacement variation of concave plate sieve of the picking device and feeding rate was carried out. The linear function, power function, exponential function, quadratic function, compound function, logarithmic function and cubic function fitting were used to perform regression analysis of the test results by using IBM SPSS software. The results showed that the cubic function model had a higher fitting precision, and its determination coefficient was 0.992. Model verification experiments were proposed, and the results showed that the established cubic function model had a good accuracy. The absolute deviation rate ranged from 0 to 4.83%, and the average deviation rate was 2.22%. The deviation rate increased with an increasing feeding rate. The field experiments also proved that there was a cubic function relationship between the feeding rate and concave plate sieve displacement, the measured concave plate sieve displacement deviation rate ranged from 0 to 6.19%, and the average deviation rate was 2.73% compared with the calculated results. This study can provide a reference for the optimization design of the structure of full-feeding picking devices for peanuts and other crops and the intelligent measurement and control of the feeding rates. [ABSTRACT FROM AUTHOR]

In order to reduce ground drop loss during mechanical pepper picking and improve the net recovery rate, a drum snap finger picking device was designed. The picking device is mainly composed of a picking drum and auxiliary picking components; the picking finger arrangement was designed biomimetically and its structure and operating parameters were optimized by the DEM (discrete element method). According to the physical and mechanical characteristics of the pepper and the simplified three-dimensional model of the picking device, a virtual simulation model of the pepper-picking device was established using the EDEM software. Through simulation analysis and using the orthogonal test method, the main factors which affect the ground drop loss rate of pepper and their optimal parameter combination values were determined. The simulation results were verified by a pepper-picking field experiment. Orthogonal tests show that, when the picking drum speed (V′) is 210 rpm, the pepper-feeding speed (V″) is 1100 mm·s−1, the bending angle of each picking spring tooth (C) is 162°, and each group of circumferential fingers has rows, the picking device has a good picking effect. At this time, the ground drop loss rates in both the simulation and field test were 7.50% and 7.85%, respectively, and the drop error was only 4.46%, which was within the allowable range. The design form and parameter optimization simulation method in this paper provide an important reference for the design and optimization of pepper-harvesting machinery.

This study designed a handheld vibrating coffee harvester to improve the mechanized harvesting of Coffea arabica L. The proposed device was used to vibrate branches of Coffea arabica L. trees, and the shedding of coffee fruit and the operation parameters of vibrational harvesting were analyzed. Images captured using high-speed photography were used to derive a force equation that represents the forced vibration of the coffee fruit-stalk joint. In addition, the vibrations of coffee berries and branches were theoretically analyzed, and the results were used to establish a dynamic vibration model of coffee trees. The shedding of coffee berries was primarily affected by the vibration frequency, vibration amplitude, and excitation position, which were simulated using a rigid–flexible branch-machine coupling model on RecurDyn software. Furthermore, field experiments were conducted to determine the optimal working parameters for coffee harvesting using vibrations. The results indicated optimal picking performance when the vibration frequency, vibration amplitude, and excitation position were 62 Hz, 9 mm, and 0.4 L, respectively. The harvesting rates of ripe and unripe coffee were 92.22% and 8.33%, respectively, and the damage rate was 5.23%. Thus, the proposed harvester can satisfactorily achieve the optimal harvesting of Coffea arabica L. [ABSTRACT FROM AUTHOR]

This study designed a handheld vibrating coffee harvester to improve the mechanized harvesting of Coffea arabica L. The proposed device was used to vibrate branches of Coffea arabica L. trees, and the shedding of coffee fruit and the operation parameters of vibrational harvesting were analyzed. Images captured using high-speed photography were used to derive a force equation that represents the forced vibration of the coffee fruit-stalk joint. In addition, the vibrations of coffee berries and branches were theoretically analyzed, and the results were used to establish a dynamic vibration model of coffee trees. The shedding of coffee berries was primarily affected by the vibration frequency, vibration amplitude, and excitation position, which were simulated using a rigid–flexible branch-machine coupling model on RecurDyn software. Furthermore, field experiments were conducted to determine the optimal working parameters for coffee harvesting using vibrations. The results indicated optimal picking performance when the vibration frequency, vibration amplitude, and excitation position were 62 Hz, 9 mm, and 0.4 L, respectively. The harvesting rates of ripe and unripe coffee were 92.22% and 8.33%, respectively, and the damage rate was 5.23%. Thus, the proposed harvester can satisfactorily achieve the optimal harvesting of Coffea arabica L.

To achieve the purpose of Ginkgo biloba leaves continuous harvesting, a ginkgo leaf picking device is designed. The device is consisted of a picking executive composed from a round rod picking hand and a rotating drum, a frame, a motor, a motor base, a coupling, a bearing seat, a motor support frame, a deciduous box, and a connecting screw. And the picking theoretical analysis and calculation are carried out. Finally, the feasibility of the design is verified by adjusting the tilt angle and motor speed of the picking device. The experimental results show that when the inclination angle between the picking device and the horizontal plane is 30° and the motor speed is 120 r/min, the damage rate of Ginkgo biloba leaves is 1.52%. The net collection rate is 94.29%, and the damage degree of branch and stem is mild. [ABSTRACT FROM AUTHOR]

Castor has been one of the most important chemical raw and strategic materials in the aviation, chemical industry, automobile, fragrance, and medicine. The annual output of castor capsules is less than 200 000 tons, while the annual demand is more than 400 000 tons in China. Therefore, it is extremely urgent for the mechanized production of castor, particularly on the harvesting in recent years. In this study, a disc-cutting picking device was designed for the castor, according to the physiological characteristics of castor plants. The device was mainly composed of the frame, double-disc cutting, capsule recycling, feeding auger, and transmission system. The disc-cutting mechanism was first utilized to separate the castor plants, and then the plant was transported on a conveying device into the cleaning section for cleaning. An optimal combination of parameters was finally achieved for the smooth cutting free of loss, where the speed and motion trajectory were determined for the disc-cutting mechanism. Some parameters were also designed, such as the rotational speed, the radius, and the installation center distance of the cutting disc. A smooth transportation without the picking loss was implemented to quickly transfer the castor plant from the cutting mechanism to the feeding auger. A clamping force of the castor plant was calculated to determine the clamping height, spacing, and working speed of the dial-tooth chain. The structural parameters of the capsule recycling mechanism were designed to avoid the dropping from the cutting device under the vibration of the harvester. An orthogonal test was carried out with the type of cutting disc, the rotational speed of the cutting disc, and the forward speed of the harvester as the test factors, while the stubble altitude difference and picking loss rate as the indexes. The results showed that an optimal combination of parameters for the stubble altitude difference was the waved-type of the disc, the disc rotational speed was 800 r/min, and the forward speed was 0.8 m/s. The type of the disc also presented a significant effect on the stubble altitude difference, but not so the disc rotational speed and forward speed. Meanwhile, the optimal picking loss rate was obtained under the waved-type structure of the disc, where the disc rotational speed was 600 r/min, and the forward speed was 1.1 m/s. There was a significant effect of the disc rotational speed on the picking loss rate, whereas, there was a very significant effect of the disc type and forward speed. Taking the picking loss rate as the main index, the integrated balance was used to determine the operating parameter, where the structure type of the disc was waved-type, the disc rotational speed was 600 r/min, and the forward speed was 1.1 m/s. A field test was carried out to verify the data. It was found that the average difference of stubble altitude was 0.85 mm, the average picking loss rate was 3.13%. The waved-type cutting disc can be an ideal cutting tool for the castor stalk with even stubble heights, indicating an excellent cutting performance, a lower loss rate, and stronger field adaptability. The finding can provide a strong reference for the development and design of castor harvesting equipment, together with the rice or corn combine harvester. [ABSTRACT FROM AUTHOR]

This study presents a tangential-axial flow picking device for peanut combine harvesting. The device was designed with reference to the tangential-axial flow threshing mechanism of the grain combine harvesters. The main purpose of this study was to solve the problem of the high rate of loss and damage in the picking operation of the peanut combine harvesters in China. Through the theoretical analysis and design calculation of the key components of the peanut picking device, the structural and working parameters were determined. The orthogonal test was carried out by taking the feeding amount of the peanut plant, the picking clearance, the speed of the tangential cylinder, and the speed of the axial cylinder as the test factors. Additionally, the non-picking loss rate, entrainment loss rate, and damage rate of the peanut pods were used as the test indexes. The test results were analyzed by range analysis and analysis of variance, and the test parameters were optimized by fuzzy comprehensive evaluation method. The optimal parameter combination for the tangential-axial flow picking device was determined as follows. The feeding amount of the peanut plant was 2 kg/s, the picking clearance was 35 mm, the speed of the tangential cylinder was 360 r/min, the speed of the axial cylinder was 425 r/min. At this time, the non-picking loss rate was 0.52%, the entrainment loss rate was 0.54%, and the damage rate was 0.75%. The test results fully met the standard requirements of the peanut picking operation. This research provides a technical basis for the application of the tangential-axial flow picking device in peanut combine harvesters.

A dynamic model and Lagrange equation of forced vibration of camellia oleifera were established for the fruit picking machine with a shaking branch mode according to the theory of forced vibration separation. The equation of inertia force for camellia oleifera fruit was also obtained by solving the governing equation. In dynamic analysis of the equation, main factors affecting the vibration of camellia oleifera can be obtained, including the vibration amplitude, frequency, action time and clamping position of the excitation force. A high speed camera was used to record the vibration shedding process of camellia oleifera fruit. The results showed that the average shedding time of fruit decreases with the increase of vibration frequency under the same amplitude. At the same frequency, the average time of fruit shedding decreased with the increase of amplitude. The picking efficiency was better when the frequency was about 6-10 Hz and the amplitude was about 20-40 mm. The average shedding time of fruit was about 4-12 s. An integrated electromechanical and hydraulic picking device of camellia oleifera fruit was designed with the frequency between 0 and 10 Hz, and the amplitude adjustable from 20 to 40 mm. A three-level orthogonal experiment for fruit picking was designed based on four factors: dynamic amplitude, frequency, action time and vibration position. According to the fact that most camellia oleifera fruits are concentrated at a distance of about 260 mm from the tree top, the height of 0-260 mm was selected as a factor level of clamping position, with an increase of 100 mm, and 260-360 and 360-460 mm were set as the other two test levels. According to the falling time of camellia oleifera fruits under different amplitudes and frequencies, the vibration frequency was selected as 6, 8 and 10 Hz, and the vibration amplitude was selected as 20, 30 and 40 mm. Since the average shedding time of camellia oleifera was between 4-12 s, the vibration time 4, 8 and 12 s were selected. The mature period of camellia oleifera fruit is generally in late October and early November. From October 30 to November 2, 2018, during the mature and suitable period of camellia oleifera fruit, 9 camellia oleifera trees of Xianglin No. 56 in the camellia oleifera forest of Qidong County, Hunan Province were selected, and 3 canopy branches with the same physical state and similar fruits amount and flower buds were selected as the picking objects, to mark and count the total fruits and flower buds on the branches. At the end of the experiment, the remaining number of camellia oleifera fruits and damaged buds were counted and recorded. The results showed that the holding lamping position of the end-effector had the greatest influence on the picking effect, while the vibration time has the least influence. The optimal picking parameters was that the clamping position was 0-260 mm from the treetop, the vibration frequency was 10 Hz, the amplitude was 20 mm, the vibration time was 8 s, under this condition, the leakage rate of fruits was the lowest (10.87%), the bud damage rate was 31.80%. Since the damage rate of flower bud was relatively large, the machine should be further improved. [ABSTRACT FROM AUTHOR]

The cotton areas in Xinjiang exceeded 2.5×106 hm² by the end of 2018, making Xinjiang the biggest cotton producer (accounting for 80% of the national cotton areas) in China. In most cotton fields in Xinjiang, the rows are spaced 560 - 760 mm and intra-row plants are spaced 96-100 mm. The average cotton yield in southern Xinjiang was approximately 7500 kg/ hm², compared with 6000 kg/ hm² in the north. Since Xinjiang is in hinterland of Eurasia, having ample sunshine, scarce precipitation and high evaporation, irrigation is essential to safeguard its agricultural production. To keep soil moisten, the planting strips for cotton are often mulched by plastic film before sowing seeds. Since natural degradation of plastic films is slow, an accumulative use of plastic film has led to soil structure degradation and environment deterioration. Recycling plastic film residuals is hence essential to developing sustainable agriculture but is challenging because the currently-used manual pick-up is labor intensive and inefficient while the available combine machines cannot separate the film residuals from cotton straw during the pick-up process. We designed a new machine aimed to solve this problem by combining film pick-up process and straw cutting-returning process. Differing from the available machines, the new one can separate the straw from the film residuals during pick-up and returning processes. It comprised a straw-cutting device, a film picking device and a film-lifting device, with all components purposely designed for cotton cultivated in Xinjiang. The operation depth of the film-lifting shovel was 54-178 mm. An orthogonal rotation test with three five-level factors was conducted to examine the impact of the speed of the spinning fling cutter, forward-speed and operation depth of the film-lifting shovel on passing rate of the crushing length, the residual film picking rate and the membrane miscellaneous separation rate from the straw. The variances were analyzed using Design-ExpertV8.0.6.1, and a regression model was used to evaluate the responsive performance of the machine to the above three operating parameters as well as their optimization. The results showed that the optimal spinning speed of the fling cutter was 1200r/min, the forward-speed was 4.5km/h, and the operation depth of the film-lifting shovel was 100mm. Field test results were consistent with these optimal parameters, with the straw crushing length pass rate being 89.37%, the residual film picking rate being 90.31%, and the membrane miscellaneous separation rate from the straw being 93.16%. It is manifest that the combine machine meets the technological requirements, improved plastic film residuals recycle efficiency and ameliorated their environmental pollution. [ABSTRACT FROM AUTHOR]

This paper is the result of studying effects of mechanical chamomile harvesting on yield and quality of harvested chamomile. Chamomile (Chamomilla recutita (L) Rausch.) was harvested at three time intervals (T1 - 240 days, T2 - 250 days and T3 - 260 days after sowing) by three conceptually different harvesters. The results achieved indicate that the harvester type significantly influences quality of harvested chamomile, whereas it is not influenced by chamomile harvesting time. Quality of harvested chamomile was classified into four categories, and it was observed that the greater number of rotations of a picking device increased the content of the first category of quality. The harvester A achieved 54.79% of the first category of quality in respect to the harvester B achieving 50.26% and the harvester C with 42.93%. [Projekat Ministarstva nauke Republike Srbije, br. TR 31051]

Pepper is one of the most vital agricultural products with high economic value, and pepper production needs to satisfy the growing worldwide population by introducing automatic seedling transplantation techniques. Optimal design and dimensioning of picking device components for an automatic pepper transplanter are crucial for efficient and effective seedling transplantation. Therefore, kinematic analysis, virtual model simulation, and validation testing of a prototype were conducted to propose a best-suited dimension for a clamp-type picking device. The proposed picking device mainly consisted of a manipulator with five grippers and a picking stand. To analyze the influence of design variables through kinematic analysis, 250- to 500-mm length combinations were considered to meet the trajectory requirements and suit the picking workspace. Virtual model simulation and high-speed photography tests were conducted to obtain the kinematic characteristics of the picking device. According to the kinematic analysis, a 350-mm picking stand and a 380-mm manipulator were selected within the range of the considered combinations. The maximum velocity and acceleration of the grippers were recorded as 1.1, 2.2 m/s and 1.3, 23.7 m/s2, along the x- and y-axes, respectively, for 30 to 90 rpm operating conditions. A suitable picking device dimension was identified and validated based on the suitability of the picking device working trajectory, velocity, and acceleration of the grippers, and no significant difference (p ≤ 0.05) occurred between the simulation and validation tests. This study indicated that the picking device under development would increase the pepper seedling picking accuracy and motion safety by reducing the operational time, gripper velocity, acceleration, and mechanical damage.

This study presents a tangential-axial flow picking device for peanut combine harvesting. The device was designed with reference to the tangential-axial flow threshing mechanism of the grain combine harvesters. The main purpose of this study was to solve the problem of the high rate of loss and damage in the picking operation of the peanut combine harvesters in China. Through the theoretical analysis and design calculation of the key components of the peanut picking device, the structural and working parameters were determined. The orthogonal test was carried out by taking the feeding amount of the peanut plant, the picking clearance, the speed of the tangential cylinder, and the speed of the axial cylinder as the test factors. Additionally, the non-picking loss rate, entrainment loss rate, and damage rate of the peanut pods were used as the test indexes. The test results were analyzed by range analysis and analysis of variance, and the test parameters were optimized by fuzzy comprehensive evaluation method. The optimal parameter combination for the tangential-axial flow picking device was determined as follows. The feeding amount of the peanut plant was 2 kg/s, the picking clearance was 35 mm, the speed of the tangential cylinder was 360 r/min, the speed of the axial cylinder was 425 r/min. At this time, the non-picking loss rate was 0.52%, the entrainment loss rate was 0.54%, and the damage rate was 0.75%. The test results fully met the standard requirements of the peanut picking operation. This research provides a technical basis for the application of the tangential-axial flow picking device in peanut combine harvesters. [ABSTRACT FROM AUTHOR]

Pepper is one of the most vital agricultural products with high economic value, and pepper production needs to satisfy the growing worldwide population by introducing automatic seedling transplantation techniques. Optimal design and dimensioning of picking device components for an automatic pepper transplanter are crucial for efficient and effective seedling transplantation. Therefore, kinematic analysis, virtual model simulation, and validation testing of a prototype were conducted to propose a best-suited dimension for a clamp-type picking device. The proposed picking device mainly consisted of a manipulator with five grippers and a picking stand. To analyze the influence of design variables through kinematic analysis, 250- to 500-mm length combinations were considered to meet the trajectory requirements and suit the picking workspace. Virtual model simulation and high-speed photography tests were conducted to obtain the kinematic characteristics of the picking device. According to the kinematic analysis, a 350-mm picking stand and a 380-mm manipulator were selected within the range of the considered combinations. The maximum velocity and acceleration of the grippers were recorded as 1.1, 2.2 m/s and 1.3, 23.7 m/s2, along the x- and y-axes, respectively, for 30 to 90 rpm operating conditions. A suitable picking device dimension was identified and validated based on the suitability of the picking device working trajectory, velocity, and acceleration of the grippers, and no significant difference (p ≤ 0.05) occurred between the simulation and validation tests. This study indicated that the picking device under development would increase the pepper seedling picking accuracy and motion safety by reducing the operational time, gripper velocity, acceleration, and mechanical damage. [ABSTRACT FROM AUTHOR]