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Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Garlic is one of the most important cash crops which cultivated widely in China. An enormous number of farms in developed countries have wide planting area, and almost all harvested garlic are sent to deep processing. Thus, there is poor requirement of garlic seed scaly direction. The high-level mechanization and automation garlic planter has been used in production as early as 1960s. In contrast, garlic is grown mostly in hills and plains, such as Hebei, Jiangsu and Shandong. The garlic planting time is about 20 days, the agronomic requirement of garlic planting is “scaly bud is upward while root is downward, and erectly planting”. In view of this special agronomic requirement, the artificial planting mode has been used in a long time, that is farmers insert garlic seed into soil in accordance with agronomic requirement and then covering soil by hands. This mode has obvious disadvantages of great labour intensity, low working efficiency and high employment cast. In addition, most foreign garlic planters are not usually suitable for use in China. Thus, an efficient precision garlic planter plays a crucial role to the development of garlic planter mechanization in China. However, the bottleneck of garlic planter research and development is how to conquer garlic seed directing technology. On the basis of this present situation, a number of universities and related scientific research institutions have carried out a series of studies and achieved periodic results. An automatic directing garlic planter was designed in this study. In terms of it, there are seed taking device, garlic seed directing device, inserted planting device and pneumatic control system, and so on. The structure of key components had been designed. A small caterpillar base plate was applied to chassis, which reduced effectively the degree of soil compaction and powered by a diesel engine. The seed taking device is composed of chain drive, seed taking spoon, chain plate and vibrating mechanism. Garlic seeds have appearance characteristics of slender scaly bud, wide tail and shape of a half moon. Based on overall dimension of garlic seeds, a seed taking spoon was designed with length as 35 mm, width as 25 mm and depth as 15 mm. The seed taking spoons were mounted on chain plate with mode of staggered arrangement in double-rows, the longitudinal space of adjacent 2 groups seed taking spoons is calculated as 228 mm. The garlic seed directing device includes 3 stages conical hopper, hopper pointed conical half top angle decreases gradually which used to assist garlic seed in adjusting postures. The best angle combination is designed by experiment as 45°, 40° and 30°. The inserted planting device includes duckbill inserted planting apparatus and reciprocating lifting apparatus. The pneumatic control system was used for realizing precise matching between chassis, seed taking device and garlic seed directing device. The main influence factors of seed taking effect and seed scaly bud directing effect were proved through experiment study. Seed taking experiment result showed that the rate of taking single seed was 93.50 %, taking multiple seeds was 2.30 %, and miss taking was 4.20 % when planter speed was 0.10 m/s. The seed directing experiment result showed the rate of seed scaly upward was 94.44 % when longitudinal space between adjacent 2 stages hoppers was 100 mm and time interval of hoppers opening was 0.4 s. Field test results showed that the rate of seed scaly upward, sowing multiple seeds and miss sowing were 89.2 %, 3.2 % and 2.0 %, respectively, the productivity scope of garlic planter was from 500 to 650 m2/h, and all indexes meet the standard requirement of garlic planting. the planter exhibited a great performance. [ABSTRACT FROM AUTHOR]

Garlic is one of the major cash crops in China, and it is mainly distributed in Shandong, Henan and Jiangsu Provinces. Single grain sowing is crucial for garlic planting, it needs to follow the agronomic requirements of root down and scaly bud upward, and therefore garlic planting mainly uses artificial means, but this method has shortcomings of strong labor intensity and low efficiency. Correspondingly, some developed countries like America and Korea have realized garlic planting mechanization in 1950-1960s, which have extensive arable land and indefinite requirement of garlic scaly bud direction when planting, and thus foreign garlic planting machinery is not suited to China’s national conditions. In recent years, the garlic planter is developed towards automation and intelligence. However, existing garlic planter is hard to distinguish the direction of garlic scaly bud, and it also has complex structure and low efficiency. The scaly bud direction distinguishing is a core technology of garlic planter, and it is also the most difficult technical operation. Therefore, how to ensure direction of the garlic seed scaly bud in the process of planting has been a key technical problem of garlic planter. According to present condition, a full-automatic extraction and release device of garlic seed box was designed based on garlic seed box method, and it can automatically track driving according to the travel speed of machine. The full-automatic extraction and release device of garlic seed box consists of drive system, conveying device, extraction and release device, speed encoder, photoelectric sensor and MCU (micro-controller unit) system. The drive system consists of stepper motor, sprocket and chain, and it has 2 parts, and one provides transmission power for the whole machine walking, and the other controls conveying device working. The conveying device consists of conveying belt, roll shaft and bearing housing, the conveying belt is transversely mounted on the frame through roll shaft and bearing housing, and its working state is controlled by MCU system. The conveying device mainly carries out transverse transportation of garlic seed boxes. The extraction and release device consists of steering wheel, central actuator, mechanical arm, auxiliary actuator and manipulator, among which the manipulator consists of U shape rotating frame, L shape mounting panel, distance controlling actuator, special shaped gear disk, connecting rod, connecting arm and claws, and it mainly realizes the functions of garlic seed boxes precision capture, smooth traffic and seamless release. The velocity measurement encoder is used for detecting unit movement speed, and provides speed messages to central actuator and distance controlling actuator. The photoelectric sensor is used to detect whether the garlic box is in place. The garlic seed box planting method reduces the damage of garlic seed and improves work efficiency, and solves the problem of the direction of garlic seed. This paper designed mechanical arm and manipulator, the mathematical model of each key component was established through the theory analysis, and thus the structure and working parameters of mechanical arm and manipulator were determined. At the same time, the influence rule of the speed of device marching on operation parameters of mechanical arm and manipulator was proved, and the influencing factors of the clearance of adjacent garlic seed boxes were specified. The test was carried out for testing the influence of the speed of device marching on the clearance of adjacent garlic seed boxes after they were released. The results showed that when the speed of marching is 0.90 km/h, and the speeds of central actuator, auxiliary actuator and distance controlling actuator are 26.04, 26.04, and 13.89 r/min, respectively, the clearance of adjacent garlic seed boxes is less, which is 5.6 mm, and the release effect is better. The machine has better stability and release effect, and work efficiency of device has been improved obviously. The research results can provide reference for realizing automation of garlic planting. [ABSTRACT FROM AUTHOR]

In order to study the damage and mechanism of corn during corn ear picking, this paper analyzed the force of corn ear when picking corn ear, and then found that there were 3 kinds of forces working on corn ear, which were the reacting force, the frictional forces of stripping roller and the force of stripping roller rib, and caused the corn ear damage with different forms. This paper made the mathematical model of forces, and analyzed their change law and their influence on the damage of corn ear. With the rising of corn ear diameter, the reacting force, the frictional forces of stripping roller and the seed loss increased. The experiments of corn ear picking were carried out on test bed. The results showed that the damage of corn seed increased as the length of corn ear was greater than 175 mm. Because with the increase of the corn ear, the center of gravity for corn ears was upward and the corn ear swing increased when it was picked, the probability of collision increased. The rate of corn damage descended as the rotating speed of stripping roller changed from 650 to 800 r/min. When the rotating speed of stripping roller was more than 800 r/min, the corn damage increased significantly. When the rotation of stripping roller became faster, the down velocity of corn ears became bigger, the impact between corn ear and stripping roller increased, and the corn damage rose. Besides, the reduction of friction between the maize straw and stripping roller was another reason for the increasing of corn damage. The corn seed loss rate decreased and then increased as the rotating speed of stripping roller changed from 650 to 750 r/min, and the corn seed loss rate decreased again as the rotating speed of stripping roller changed from 750 to 850 r/min. Because when the rotation of stripping roller became faster, the corn ear down speed became bigger, the impact between the corn ear and stripping roller increased. The corn damage and seed loss decreased and then increased as the stripping roller clearance changed from 8 to 15 mm. The corn damage and seed loss were the minimum when the stripping roller clearance was 10 mm, and then with the clearance of stripping roller increasing, the corn damage and seed loss ascended, which was consistent with the result of theoretical analysis. And the mechanical damage form of corn usually included corn nibbled, corn impacted, corn extruded and broken corn ear. The process of corn ear picking was recorded with the high-speed camera and the movement of corn ear was analyzed. The results indicated that the moving velocity of corn ear had no effect on corn damage. It was also observed from the record that the moving state of corn ear picking had 3 types: first, corn ear was picked smoothly and entered the conveyer device; second, corn ear bounced; third, corn ear picking became difficult or corn ear contacting stripping roller for a long time. And the corn ear damage became more serious with the increasing of the contacting time between corn ear and stripping roller. [ABSTRACT FROM AUTHOR]

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)