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Vegetables have the largest planting areas besides grains. Machine vision navigation has been one of the most crucial indicators of mechanization, automation, and intelligence in modern agriculture. Most vegetable transplanters are still manually driven at present. It is also necessary to detect the ridge mounds before the navigation of the transplanter. Since the ridge mounds are often free of crops before transplanting, it is still challenging to find references. Therefore, it is a high demand to extract the navigation lines with crop-free ridges mounds under complex scenes. There was also similar color information and small texture difference in crop-free ridges rows. Traditional image processing cannot fully meet large-scale production. In this study, a ridge row segmentation model was proposed using an improved version of DeepLabV3+. The real-time performance of semantic segmentation was also achieved with the high applicability, accuracy, and detection speed. The traditional DeepLabV3+ network was simplified to replace the Xception backbone network with the MobileNetV2 network. The speed of detection and the real-time performance were obtained after that. The DeepLabV3+ model incorporated the Convolutional Block Attention Module attention mechanism, in order to better treat the ridge boundary information. The important details of the ridge boundary were focused to accurately detect and classify the target objects. Navigational feature points were obtained using the ridge boundary information. In cases where the seedlingless ridges were present, the navigational feature points were deviated from the intended positions. Accordingly, the feature points were adjusted for the guidance of accurate navigation. The quartiles were utilized to filter out any outliers among the navigation feature points. Any data points were identified and removed to deviate significantly from the norm. In addition, the least squares method was used to fit the navigation line using the fitted feature points. A reliable reference of the navigation line was then obtained to compensate for any deviations from the seedlingless ridges. Overall, the simplified DeepLabV3+ network with the MobileNetV2 backbone was incorporated with the CBAM attention mechanism. There were the high detection speed, real-time performance and accurate navigations, even in the challenging scenarios with the ridge boundaries. Two locations were also selected from the images, in order to improve the applicability of the model in the environments of crop-free ridges. The challenge remained on the different soil qualities, lighting conditions and seedlingless ridges in the field test. The dataset consisted of 1350 images in the training set, and 150 images in the validation set. The images were then expanded using data enhancement. The results indicate that the improved model was achieved with an average pixel accuracy of 96.27%, an average intersection and merger ratio of 93.18%, and an average detection frame rate of 84.21 frames per second. The average intersection and merger ratio, the average pixel accuracy, and the frame rate were improved by 1.78 percentage points, 0.83 percentage points, and 29.32, respectively, compared with the pre-improvement period. The best performance was then achieved in the MobileNetV2, thus meeting the requirements for navigation recognition, compared with the various backbone networks. On average, the pixel accuracies of the model were improved by 0.83 and 3.28 percentage points, respectively, compared with the Xception and MobileNetV3. Furthermore, the improved model also demonstrated better average accuracy, average intersection ratio, and frame rate than PSPNet, U-Net, HRNet, Segformer, and DeepLabV3+. The Hough transform and Random Sample Consensus were much less effective in obtaining the navigation lines from different scenes, compared with the maximum angular error of 1.2° and the maximum pixel distance error of 9 in various ridges environments. These findings can serve as a strong reference for crop-free ridge navigation in agricultural robots, thus promoting the development of intelligent agricultural equipment. [ABSTRACT FROM AUTHOR]

An end-effector is one of the most important components in the fruit picking robot. The picking mechanism of the end-effector can also dominate the picking efficiency. However, the picking end-effector with the fixed structure and parameters cannot fully meet the picking needs of different fruit diameter ranges, due to the wide variety of objects being picked at present. In this study, an underactuated articulated end-effector was designed, including four picking fingers. Each picking finger with two joints was driven by a connecting rod to simulate the human envelope-picking action. The hand with the intention of picking citrus was used to simulate a similar spherical fruit. The better performance of the end-effector was achieved in the small number of system drives, the low overall system complexity, and the small damage to the fruit during the picking process. A parametric design was also proposed using an improved genetic algorithm (GA), in order to improve the repetitive design of this type of end-effector. The picking range of fruit diameters was expanded to improve the feasibility of the movement. Microsoft Visual Studio 2012 development platform was utilized to customize the MFC design parameter interface. The end-effector structure was then previewed to input the initial parameters in the interface. The improved GA optimization was adopted to combine with the secondary development module NXOpen of NX. The parameters were assigned to the mechanism model in the form of expressions during optimization. Specifically, the structural parameters were optimized during this time. The end-effector was pre-modeled to fully meet the optimal picking conditions. Adams platform was employed to conduct the dynamic simulation analysis on the optimized grasping end-effector model. The maximum displacement offset of the optimized end-effector increased by about 29.1%. The optimal displacement value was achieved in the objective function. The simulation curve image was added into the parametric design system for display through the Python script. The correctness of the optimal design was then verified after simulation. A physical prototype was carried out indoor and orchard citrus picking experiments, according to the designed end-effector mechanism. In the laboratory environment, the success rate of envelope picking reached 100% for 20 citruses with a diameter in the range of 64-102 mm. The end-effector was connected to the self-made robotic arm. The end of the mechanical arm turned the end-effector "wrist" after the finger mechanism formed an envelope, and then twisted the fruit handle to complete the picking. Picking experiments were performed on the citrus with the different fruit diameters in the orchard. The test results show that the success rate of picking citrus with a diameter of 68-106 mm reached 92.9%. The displacement parameters of the optimized end-effector were measured to obtain the maximum displacement (61.4 mm) of the single-ended joint, similar to the Adams simulation. Since the maximum offset was set in the optimization objective function, there was a threshold for the maximum opening of the picking node, in order to reduce the interference of branches and leaves. The total success rate reached 92.9% in the picking test. The parametric design can realize the rapid deformation response of the end-effector to the spherical fruits with different fruit diameter ranges. GA was also used to optimize the working parameters of the mechanism, in order to improve the feasibility of picking and the accuracy of mechanism design. [ABSTRACT FROM AUTHOR]

Inferior bowl seedlings have posed a great threat to the survival rate of later seedling transplantation in greenhouse hole tray seedling cultivation. It is urgent to remove the matrix blocks of these holes before leaving the factory. However, the existing mechanical removal often causes the particle scattering and omission. Air suction removal can be expected to effectively compensate for this defect. In this study, a series of experiments were conducted to optimize and then verify the structural parameters in the matrix air suction removal scheme. A systematic analysis was implemented to determine the relationship between pipeline design and adsorption efficiency under negative pressure. A single factor experiment was also carried out to preliminarily select the optimal values of pipe diameter (10, 18, 26, and 32 mm), pipe spacing (0, 4, 8, and 12 mm), and pipe length (1 000, 2 000, 3 000, and 4000 mm). A optimal combination was obtained with the pipe diameter 26 mm, pipe spacing 6 mm, and pipe length 2 000 mm. Further expansion was carried out with 200-hole potted seedlings as the research object (The seedling emergence rate of the entire tray was 92%, and the health rate was 86%). Four factors were performed on the substrate removal rate, including pipe type (round tube, flat tube, and square tube), pipe diameter (inner diameter of 23, 26, and 29 mm), pipe spacing (2, 6, and 10 mm), and pipe length (1 000, 2 000, and 3 000 mm). Response surface analysis was conducted as well. The experimental results show that all four factors posed an impact on the matrix removel rate. Firstly, the pipe spacing and the pip type shared the greatest impact on the matrix removel rate, and then the pipe diameter. Nevertheless, there was the little effect of pipe length on the cleaning. Reasonable scaling was carried out in the later experimental design. Secondly, the larger the pipe diameter was, the better performance was. It was also necessary to consider the limitation of hole space and the damage to adjacent hole healthy seedlings. The smaller the pipe spacing was, the greater the negative pressure capacity was, and the better the matrix removel rate was, but the suction cup phenomenon was more serious. There was the little impact of the pipe length on the overall suction, but it cannot be ignored. Finally, the optimal combination of various factors was achieved: a square tube, an inner diameter of 26 mm at the end of the straw, a distance of 3 mm from the end of the straw to the port on the hole, and a length of approximately 1000 mm. Consequently, 95% matrix removal was achieved at the maximum negative pressure of 22 kPa,which is an average increase of 2.94% compared to before optimization. More efficient substrate removal was achieved under the same negative pressure. The better performance was gained than the mechanical removal equipment of low-quality bowl seedling substrate. This finding and also provide the data reference for the design and development of removal equipment with substrate negative pressure. [ABSTRACT FROM AUTHOR]

Rice potted-seedlings transplanting is one kind of rice planting way, and it can increase the production and improve rice quality because it has the advantages of not hurting root and not needing recovering period. The rice pot seedling transplanting will have a good prospect in the future, but at present the application of rice pot seedling transplanting machine is less in China because there are defects for domestic transplanter with tossing transplanting such as uncontrollable seedling perpendicularity, complex structure, low efficiency and heavy vibration. Foreign rice potted-seedling planting technology is not suitable in China for complicated structure and high cost, and the key to improve the mechanization of rice planting is to research the rice potted-seedling transplanting mechanism suitable to China. Aiming to the above problems, a three-transplanting-arm rice potted-seedling transplanting mechanism of planetary gear train with non-circular gears and incomplete non-circular gear, which is applied in automatic rice potted-seedling transplanter, was designed. The mechanism consists of an incomplete non-circular gear, 3 pairs of conjugate non-circular gears and 3 planting arms, which can transplant seedlings 3 times a week. It means that under the same transplanting efficiency, it can reduce the transplanting spindle rotation, so as to reduce the vibration and improve the success rate of transplanting. Firstly, the shortcomings of the rotary transplanting mechanism with 2 transplanters were analyzed, and the design requirements were put forward. According to the requirements, the implementation plan was advanced. Then, the operation principle of rice potted-seedling transplanting mechanism was introduced, the mathematical expression in parametric form for the trajectory and the equations of non-circular gears and incomplete non-circular gears were derived, and the kinematic model of transplanting mechanism was established. A computer-aided analysis and optimization software of this kind of rice potted-seedling transplanting mechanism was developed with the Visual Basic 6.0. With the method of human-computer interaction based on visualization, the optimization design of the transplanting mechanism was carried out. Using this software, by tuning the design parameters, the influence of every parameter on the optimization object could be found out. The curve of non-circular gears was optimized and the structural parameters were obtained, which can satisfy the requirements of trajectory and attitude in the transplanting process for rice potted-seedling. The 3D (three-dimensional) model of transplanting mechanism was built and assembled in UG's entity modeling module. The virtual prototype was imported into Adams software after the interference checking of 3D model assembly was finished. According to the comparison between the virtual prototype simulation and the theoretical analysis of VB (Visual Basic), the trajectory of them was fundamentally consistent, so the correctness of the model of VB was verified, and the simulation results initially showed the design of mechanism was rational. In order to further verify the correctness of the design, the core components of transplanting mechanism were machined and assembled. Then, the physical prototype of the transplanting mechanism was developed to carry out the kinematics test in the test shelf. The results turned out that the static trajectory of the elastic tip of this transplanting arm and transplanting posture were basically consistent between the virtual prototype simulation and the physical prototype test, which proved the rationality and effectiveness of the parameters of transplanting mechanism. And the feasibility of this transplanting mechanism was verified. At the same time, the mechanism proposed solved the problem of seedling lodging and low transplanting success rate, and the efficiency of transplanting was improved. The research can provide a theoretical basis f [ABSTRACT FROM AUTHOR]

In order to develop a more efficient and universal flower auto-transplantation technique, an auto-transplantation mechanism with the integrated function of seedling pick-up and transplanting has been designed. This mechanism involves gear driving and two transplanting arms of the same structure. The gear driving system is made up of one semi-circle gear, four oval planet gears and concave-convex lock-up arc. It aims to move with the non uniform speed through the operation of planet gears and pulling and imbedding of concave-convex lock-up arc. The auto-transplantation arm includes the transplanting claw, convex gear and removing gear-gap parts. It transfers the whirling operation of planet gear into straight-line operation of pick-up seedling. The manual finger scratching and planting were simulated by two pins at the end of the seedling arm. The auto-transplantation mechanism combines the pick-up and planting. The transplanting trajectory and the location of pick-up and planting were special. Thus, it is essential to design new mechanism accordance with the movement of pick-up clip and achieve “Double beak sharp” trajectory. In this paper, we designed a device of bouncing clip to lengthen the trajectory to realize the function of pick-up and planting, and it could facilitate the integration of the planting. At the same time, when the claw moves nearly to the pot seedling, the seedling needle was inserted into the soil with a certain angle of inclination, which could effectively avoid the injury of the seedlings and the interference with the seedling box. Based on the kinematics characteristics of the mechanism, a corresponding mathematic model was established, and the Visual Basic 6.0 software was used to optimize the mechanism parameters. The program was used to analyze the influence of the parameters of mechanism on the trajectory and attitude of the “Double beak sharp". Finally, the best group of mechanism parameters was selected, and then the 3D design and components assembly were carried out based on SolidWorks 2015 software. Importing the 3D model to Adams, the trajectories of seedling needle could be obtained by the kinematics simulation. Finally, the prototype test was carried out and the test trajectory of the prototype was obtained by the test platform. Through the platform, the operation process was recorded by high-speed camera. Therefore, the trajectories of seedling needle could be tracked through the Bestcam picture analysis software. The results were basically the same among the simulation trajectory, the test trajectory of the prototype and the theoretical trajectory, which verified the correctness and feasibility of the design in this paper. Experimental research was carried out using the prototype, “Marigold chrysanthemum” seedlings were selected in the experiment, the basic composition of the pot seedling combines the pearl cave and peat mud, with the water component of 46%, the seedling tray were eight lines and 16 rows, both the length and width of seedling were 31 mm, and depth was 43 mm, and the test seedlings of marigold were 35 days, with the average height of 10 cm. The rotation speed of the mechanism was set as 35 r/min, its mean efficiency was 70 stems per minute. The obtained seedling success rate was 97.27%, while the transplanting success rate was 77.62%. It reflected the practicality of the integrated transplanting mechanism; the research could provide a reference for the key technology of automatic transplanting. [ABSTRACT FROM AUTHOR]

Vegetable pot seedling transplantation has many advantages, such as high survival rate, promoting crop early maturity and improving land use rate. Mechanized transplanting of vegetable can be divided into semi-automatic transplanting and fully-automatic transplanting. Semi-automatic transplanting is mainly carried out by feeding the seedlings into the seedling transplanter manually, which has low efficiency and high labor intensity, and it is not conducive to field operations. At present, the automatic transplanting machine mainly adopts multiple mechanisms to complete a series of actions such as picking up seedling, conveying and planting, but it has the disadvantages of complex structure, high cost and low efficiency. In order to simplify the structure, the way to complete the transplanting operation with a single mechanism is proposed. However, due to the complicated working trajectory of transplanting vegetable seedling and much posture requirements, the transmission ratio of the mechanism is required to be changed greatly, which resulting in the irregular shape of the non-circular gear section of the single planetary gear is not conducive to processing and affects the transmission performance of the gear. A double-planetary non-circular gears linkage of vegetable pot seedling transplanting mechanism is proposed to solve the problem mentioned above in this paper. The transmission part of transplanting mechanism is composed of planetary gear train mechanism and crank rocker mechanism, The main planetary frame rotates at a uniform speed, through the transmission of internal gears and connecting rods, the unequal transmission of non-circular gear system and the periodic variable-speed swing of crank-rocker mechanism are superimposed, which makes the sub-planetary frame swing with respect to the main planetary frame and the transplanting arm rotate with respect to the sub-planetary frame, thus the transmission ratio needed to realize the complex transplanting trajectory and posture is obtained. Non-uniform B-spline curve is applied to fit the pitch curve of non-circular gear to obtain closed, smooth and continuous pitch curves, and the mathematical model of gear train is established based on coordinate transformation theory. Based on the development platform of Matlab, an optimization program is compiled to analyze the effect of transmission case noncircular gear pitch curve and crank rocker mechanism on the shape of trajectory. Further, the effects of the structure and position parameters of the gears and transplanting arm on the target parameters of the transplanting trajectory are analyzed. According to the requirements of 220 mm planting spacing, 120 mm seedling height and 40 mm deep pot for celery transplantation, a set of sharp beak trajectory that satisfies the requirements of the operation posture of picking up seedling and planting is optimized. The optimizing values are that the length of the picking up seedling trajectory is 33 mm, the distance from the lowest point of the trajectory to the lowest point of the planet carrier is 55 mm, the angle of picking up seedlings is 23°, the angle of change in the process of picking up seedlings is 16°, the angle of planting seedlings is 65°, the whole height of the trajectory is 355 mm, and the height of the buckle of the moving trajectory is 125 mm. A three-dimensional model of the mechanism is built and a virtual simulation is performed based on the optimization result. The results show that the simulated trajectory and velocity of the transplanting mechanism are basically consistent with the theoretical results. The trajectory and postures of the transplanting arm are analyzed by a test bench, industrial camera and image processing software. The results show that the trajectory of seedling-taking and seedling-pushing sections coincides with the simulation trajectory basically and the theoretical data, and the error is within 2 mm, which can meet the requirements of transplanting operation, the transplanting mechanism designed is reasonable and feasible. [ABSTRACT FROM AUTHOR]

In order to develop a more efficient and universal flower auto-transplantation technique, an auto-transplantation mechanism with the integrated function of seedling pick-up and transplanting has been designed. This mechanism involves gear driving and two transplanting arms of the same structure. The gear driving system is made up of one semi-circle gear, four oval planet gears and concave-convex lock-up arc. It aims to move with the non uniform speed through the operation of planet gears and pulling and imbedding of concave-convex lock-up arc. The auto-transplantation arm includes the transplanting claw, convex gear and removing gear-gap parts. It transfers the whirling operation of planet gear into straight-line operation of pick-up seedling. The manual finger scratching and planting were simulated by two pins at the end of the seedling arm. The auto-transplantation mechanism combines the pick-up and planting. The transplanting trajectory and the location of pick-up and planting were special. Thus, it is essential to design new mechanism accordance with the movement of pick-up clip and achieve “Double beak sharp” trajectory. In this paper, we designed a device of bouncing clip to lengthen the trajectory to realize the function of pick-up and planting, and it could facilitate the integration of the planting. At the same time, when the claw moves nearly to the pot seedling, the seedling needle was inserted into the soil with a certain angle of inclination, which could effectively avoid the injury of the seedlings and the interference with the seedling box. Based on the kinematics characteristics of the mechanism, a corresponding mathematic model was established, and the Visual Basic 6.0 software was used to optimize the mechanism parameters. The program was used to analyze the influence of the parameters of mechanism on the trajectory and attitude of the “Double beak sharp". Finally, the best group of mechanism parameters was selected, and then the 3D design and components assembly were carried out based on SolidWorks 2015 software. Importing the 3D model to Adams, the trajectories of seedling needle could be obtained by the kinematics simulation. Finally, the prototype test was carried out and the test trajectory of the prototype was obtained by the test platform. Through the platform, the operation process was recorded by high-speed camera. Therefore, the trajectories of seedling needle could be tracked through the Bestcam picture analysis software. The results were basically the same among the simulation trajectory, the test trajectory of the prototype and the theoretical trajectory, which verified the correctness and feasibility of the design in this paper. Experimental research was carried out using the prototype, “Marigold chrysanthemum” seedlings were selected in the experiment, the basic composition of the pot seedling combines the pearl cave and peat mud, with the water component of 46%, the seedling tray were eight lines and 16 rows, both the length and width of seedling were 31 mm, and depth was 43 mm, and the test seedlings of marigold were 35 days, with the average height of 10 cm. The rotation speed of the mechanism was set as 35 r/min, its mean efficiency was 70 stems per minute. The obtained seedling success rate was 97.27%, while the transplanting success rate was 77.62%. It reflected the practicality of the integrated transplanting mechanism; the research could provide a reference for the key technology of automatic transplanting. [ABSTRACT FROM AUTHOR]

In order to develop a more efficient and universal flower auto-transplantation technique, an auto-transplantation mechanism with the integrated function of seedling pick-up and transplanting has been designed. This mechanism involves gear driving and two transplanting arms of the same structure. The gear driving system is made up of one semi-circle gear, four oval planet gears and concave-convex lock-up arc. It aims to move with the non uniform speed through the operation of planet gears and pulling and imbedding of concave-convex lock-up arc. The auto-transplantation arm includes the transplanting claw, convex gear and removing gear-gap parts. It transfers the whirling operation of planet gear into straight-line operation of pick-up seedling. The manual finger scratching and planting were simulated by two pins at the end of the seedling arm. The auto-transplantation mechanism combines the pick-up and planting. The transplanting trajectory and the location of pick-up and planting were special. Thus, it is essential to design new mechanism accordance with the movement of pick-up clip and achieve “Double beak sharp” trajectory. In this paper, we designed a device of bouncing clip to lengthen the trajectory to realize the function of pick-up and planting, and it could facilitate the integration of the planting. At the same time, when the claw moves nearly to the pot seedling, the seedling needle was inserted into the soil with a certain angle of inclination, which could effectively avoid the injury of the seedlings and the interference with the seedling box. Based on the kinematics characteristics of the mechanism, a corresponding mathematic model was established, and the Visual Basic 6.0 software was used to optimize the mechanism parameters. The program was used to analyze the influence of the parameters of mechanism on the trajectory and attitude of the “Double beak sharp". Finally, the best group of mechanism parameters was selected, and then the 3D design and components assembly were carried out based on SolidWorks 2015 software. Importing the 3D model to Adams, the trajectories of seedling needle could be obtained by the kinematics simulation. Finally, the prototype test was carried out and the test trajectory of the prototype was obtained by the test platform. Through the platform, the operation process was recorded by high-speed camera. Therefore, the trajectories of seedling needle could be tracked through the Bestcam picture analysis software. The results were basically the same among the simulation trajectory, the test trajectory of the prototype and the theoretical trajectory, which verified the correctness and feasibility of the design in this paper. Experimental research was carried out using the prototype, “Marigold chrysanthemum” seedlings were selected in the experiment, the basic composition of the pot seedling combines the pearl cave and peat mud, with the water component of 46%, the seedling tray were eight lines and 16 rows, both the length and width of seedling were 31 mm, and depth was 43 mm, and the test seedlings of marigold were 35 days, with the average height of 10 cm. The rotation speed of the mechanism was set as 35 r/min, its mean efficiency was 70 stems per minute. The obtained seedling success rate was 97.27%, while the transplanting success rate was 77.62%. It reflected the practicality of the integrated transplanting mechanism; the research could provide a reference for the key technology of automatic transplanting. [ABSTRACT FROM AUTHOR]

In order to develop a more efficient and universal flower auto-transplantation technique, an auto-transplantation mechanism with the integrated function of seedling pick-up and transplanting has been designed. This mechanism involves gear driving and two transplanting arms of the same structure. The gear driving system is made up of one semi-circle gear, four oval planet gears and concave-convex lock-up arc. It aims to move with the non uniform speed through the operation of planet gears and pulling and imbedding of concave-convex lock-up arc. The auto-transplantation arm includes the transplanting claw, convex gear and removing gear-gap parts. It transfers the whirling operation of planet gear into straight-line operation of pick-up seedling. The manual finger scratching and planting were simulated by two pins at the end of the seedling arm. The auto-transplantation mechanism combines the pick-up and planting. The transplanting trajectory and the location of pick-up and planting were special. Thus, it is essential to design new mechanism accordance with the movement of pick-up clip and achieve “Double beak sharp” trajectory. In this paper, we designed a device of bouncing clip to lengthen the trajectory to realize the function of pick-up and planting, and it could facilitate the integration of the planting. At the same time, when the claw moves nearly to the pot seedling, the seedling needle was inserted into the soil with a certain angle of inclination, which could effectively avoid the injury of the seedlings and the interference with the seedling box. Based on the kinematics characteristics of the mechanism, a corresponding mathematic model was established, and the Visual Basic 6.0 software was used to optimize the mechanism parameters. The program was used to analyze the influence of the parameters of mechanism on the trajectory and attitude of the “Double beak sharp". Finally, the best group of mechanism parameters was selected, and then the 3D design and components assembly were carried out based on SolidWorks 2015 software. Importing the 3D model to Adams, the trajectories of seedling needle could be obtained by the kinematics simulation. Finally, the prototype test was carried out and the test trajectory of the prototype was obtained by the test platform. Through the platform, the operation process was recorded by high-speed camera. Therefore, the trajectories of seedling needle could be tracked through the Bestcam picture analysis software. The results were basically the same among the simulation trajectory, the test trajectory of the prototype and the theoretical trajectory, which verified the correctness and feasibility of the design in this paper. Experimental research was carried out using the prototype, “Marigold chrysanthemum” seedlings were selected in the experiment, the basic composition of the pot seedling combines the pearl cave and peat mud, with the water component of 46%, the seedling tray were eight lines and 16 rows, both the length and width of seedling were 31 mm, and depth was 43 mm, and the test seedlings of marigold were 35 days, with the average height of 10 cm. The rotation speed of the mechanism was set as 35 r/min, its mean efficiency was 70 stems per minute. The obtained seedling success rate was 97.27%, while the transplanting success rate was 77.62%. It reflected the practicality of the integrated transplanting mechanism; the research could provide a reference for the key technology of automatic transplanting. [ABSTRACT FROM AUTHOR]

In order to develop a more efficient and universal flower auto-transplantation technique, an auto-transplantation mechanism with the integrated function of seedling pick-up and transplanting has been designed. This mechanism involves gear driving and two transplanting arms of the same structure. The gear driving system is made up of one semi-circle gear, four oval planet gears and concave-convex lock-up arc. It aims to move with the non uniform speed through the operation of planet gears and pulling and imbedding of concave-convex lock-up arc. The auto-transplantation arm includes the transplanting claw, convex gear and removing gear-gap parts. It transfers the whirling operation of planet gear into straight-line operation of pick-up seedling. The manual finger scratching and planting were simulated by two pins at the end of the seedling arm. The auto-transplantation mechanism combines the pick-up and planting. The transplanting trajectory and the location of pick-up and planting were special. Thus, it is essential to design new mechanism accordance with the movement of pick-up clip and achieve “Double beak sharp” trajectory. In this paper, we designed a device of bouncing clip to lengthen the trajectory to realize the function of pick-up and planting, and it could facilitate the integration of the planting. At the same time, when the claw moves nearly to the pot seedling, the seedling needle was inserted into the soil with a certain angle of inclination, which could effectively avoid the injury of the seedlings and the interference with the seedling box. Based on the kinematics characteristics of the mechanism, a corresponding mathematic model was established, and the Visual Basic 6.0 software was used to optimize the mechanism parameters. The program was used to analyze the influence of the parameters of mechanism on the trajectory and attitude of the “Double beak sharp". Finally, the best group of mechanism parameters was selected, and then the 3D design and components assembly were carried out based on SolidWorks 2015 software. Importing the 3D model to Adams, the trajectories of seedling needle could be obtained by the kinematics simulation. Finally, the prototype test was carried out and the test trajectory of the prototype was obtained by the test platform. Through the platform, the operation process was recorded by high-speed camera. Therefore, the trajectories of seedling needle could be tracked through the Bestcam picture analysis software. The results were basically the same among the simulation trajectory, the test trajectory of the prototype and the theoretical trajectory, which verified the correctness and feasibility of the design in this paper. Experimental research was carried out using the prototype, “Marigold chrysanthemum” seedlings were selected in the experiment, the basic composition of the pot seedling combines the pearl cave and peat mud, with the water component of 46%, the seedling tray were eight lines and 16 rows, both the length and width of seedling were 31 mm, and depth was 43 mm, and the test seedlings of marigold were 35 days, with the average height of 10 cm. The rotation speed of the mechanism was set as 35 r/min, its mean efficiency was 70 stems per minute. The obtained seedling success rate was 97.27%, while the transplanting success rate was 77.62%. It reflected the practicality of the integrated transplanting mechanism; the research could provide a reference for the key technology of automatic transplanting. [ABSTRACT FROM AUTHOR]

To improve the efficiency of mechanization in transplanting vegetable seedlings and achieve the automation of vegetable transplanter in dry land, an automatic vegetable pot seedling transplanter for dry land was developed. This transplanter is mainly composed of 2 rotating seedling picking-up mechanisms of planetary gear train with ellipse gears and incomplete non-circular gears, a horizontal and longitudinal intermittent seedling sending device, 2 eccentric disc dibble-type planting apparatuses, and a power transmission system. Two rotating seedling picking-up devices and 2 eccentric disc dibble-type planting apparatuses were symmetrically arranged along the longitudinal surface center of the machine, constituting 2 sets of automatic seedling picking-up and planting systems. The seedlings were provided automatically from 2 standard seedling pots with 128 holes using the horizontal and longitudinal intermittent seedling sending device. The engine drive shaft could transfer power to the principal axis of the apparatus through chain drive to enable the rotating and planting of the apparatus. Meanwhile, the principal axis of the apparatus could transfer the power to the rotating seedling picking-up mechanisms of planetary gear train with ellipse gears and incomplete non-circular gear and intermittent seedling sending device. Subsequently the intermittent seedling sending device could move horizontally and longitudinally to send the seedling pots to the target place, where the seedling picking-up mechanism took the seedlings from the pot to the eccentric disc dibble-type planting apparatus. To test the performance of this automatic vegetable pot seedling transplanter for dry land, the experiments were conducted in the test field where the soil condition met the mechanical industry standard in People's Republic of China Dry Land Planting Machinery (JB/T 10291-2013). The tomato seedlings (ZheZa 809) used in this experiment were cultivated in the standard seedling pots with 128 holes and transplanted at the age of 35 days with an average height of 150 mm. The seedling sending, picking-up, delivering and planting were all carried out at a constant transplanting frequency by adjusting the speed of the input belt pulley of the walking gear-box. The seedling transplanting efficiency was tested at the low speeds of 45, 60, 75 and 84 plants/min, respectively, as well as at the high speed of 96 plants /min. The coefficient of variation for planting spacing, missing transplanting rate, qualified rate of planting depth and qualified rate of transplanting were determined according to the mechanical industry standard Dry Land Planting Machinery (JB/T10291-2013). The seedling-standing ratio was calculated based on the Technical Specifications of Quality Evaluation for Rape Transplanter (NY/T 1924-2010) according to the standards for agriculture industry in People's Republic of China. The results showed that the coefficient of variation for planting spacing and the missing transplanting rate increased slightly at the range of 6.6%-8.9% and 1.7%-2.8% accordingly when increasing the planting frequency from 45 to 96 plants/min. However, the qualified rate of planting depth, the qualified rate of planting perpendicularity and the qualified rate of transplanting decreased slightly in the range of 97.5%-98.9%, 96.7%-97.8%, and 91.1%-94.7% with the increasing of planting frequency. The coefficient of variation for planting spacing, the missing transplanting rate, the qualified rate of planting depth and the qualified rate of planting all met the requirements of the machinery industry standards (JB/T 10291-2013), and the qualified rate of planting perpendicularity was also within the specified value in the standards for agriculture industry (NY/T 1924-2010). The automatic seedling-sending device, the seedling picking-up device and the planting apparatus of the automatic transplanter coordinated well with each other to complete the process for sending seedlings, picking up seedlings, delivering seedling, planting and soil covering automatically. [ABSTRACT FROM AUTHOR]