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In this study, to address the problems of difficulties in harvesting side rows, poor quality of cutting and tanning laying, and poor passing performance of the machine caused by low chassis of conventional cutter-rower and the structure type of vertical cutting table with lateral laying, a horizontal cutter-rower was designed with the form of middle laying and the drive system was driven by hydraulic motor. The structure of the machine was mainly composed of eccentric grain wheel, suspension lifting device, grain splitting device, transverse reciprocating cutter, transverse spiral conveyor drum, frame, transmission system, and hydraulic system. The cutting diagrams under different unit forward speed and different crank speed were drawn by using MATLAB programming. The orthogonal test was conducted with the laying uniformity coefficient and cutting and tanning loss coefficient as experimental indexes and with the forward speed of the machine and the main drive shaft speed as the test factors. The results showed that the machine worked best when the forward speed was 1.07 m/s and the main drive shaft speed was 449 r/min, and the average value of the laying uniformity coefficient was 1.08 and the average value of the cutting and tanning loss coefficient was 1.55. The field test results showed that the cutter-rower could complete the cutting and laying of oats at one time under normal working condition, with neat stubble cutting, smooth conveyance and orderly laying, it could meet the requirements of subsequent drying and picking and threshing operations. [ABSTRACT FROM AUTHOR]

Caragana korshinskii (C.K.) flat stubble residue is an abundant biomass energy source in China. Because branch cutting is closely related to the harvesting of forest biomass, it is practical for forestry production and ecological development to investigate the effects of cutting parameters on the peak cutting force and cutting energy consumption of C.K. branches. In this study, the effect of cutting parameters on the peak cutting force and cutting power consumption of branches was investigated by single-factor and multi-factor tests using an independently developed reciprocating cutting test bench, and an optimization model was established. The interaction term of average cutting speed and tool cutting edge inclination angle significantly affected the peak cutting force, while the interaction term of cutting clearance and wedge angle had a significant effect on the cutting energy consumption. The optimal combination of cutting parameters was an average cutting speed of 0.5 m/s, cutting clearance of 1.4 mm, wedge angle of 25°, and tool cutting edge inclination angle of 20°. With this combination of parameters, the corresponding peak cutting force was 644.38 N, and the cutting energy consumption was 5.90 J, which was less than 5% relative error between each performance index and the theoretical optimized value.

Chinese high-quality tea can be specially required for the appearance quality of tea leaves. Particularly, every single tea bud should be intact with the uniform length of all buds. Chinese famous tea is still widely picked by hand, due to the high breakage of tea shoots that are plucked by machines even the state-of-the-art ones. However, manual harvesting cannot fully meet large-scale tea production in recent years, leading to high labor intensity with low efficiency. It is absolutely necessary and urgent to investigate the suitable plucking machines for Chinese high-quality tea at present. Among them, the commonly-used reciprocating-cutting-type cutter was the core reason for the high tea crushing rate in the bulk tea plucking machine. As a result, the machine cannot be suitable for the high-quality tea. In this study, an optimization experiment was carried out on the structure and parameters of the cutter, in order to develop an excellent plucking tool for the high-quality tea. Firstly, the specific structure of the cutter was introduced to analyze the motion characteristics of the blade. The cutter device consisted of two blades, a double eccentric cam shaft, a driving box, and some standard units. When actuated by the motor through the shaft, the motion of the blade approximated a sine function without considering the micro deformation. The cut diagram was then drawn to determine the main factors for the high crushing rate of the machine. The results show that the main factors influencing the picking quality included the machine moving speed, speed ratio between cutter and machine, reciprocating movement stroke, and cutter tooth height, referring to the moving speed, speed ratio, stroke, and tooth height, respectively. These resulting factors interacted with each other for the complex tea plucking. Hence, comprehensive optimization was very necessary to clarify the plucking effect of every single factor, rather than the cut diagram only. Secondly, an electrical test platform was designed with the rail-type tea plucking to permit the setting of exactly the velocity values of cutting and driving needed in the experiment within a certain range. The self-propelled tea plucking machine was also designed before. The high precision values were achieved in the 0.1 (r/min) and 0.01 (m), respectively. A quadratic regression orthogonal rotary center combination test was carried out on the test platform. The nine pairs of blades were produced with different structure parameters, according to the test scheme. Then, the parameter optimization model was established with the evaluation indexes (including the integrity percentage of sprout leaves, leakage rate, and complete rate stubble roughness). The improved model was solved with the genetic algorithm (GA). The best combination of parameters was obtained for the machine as follows: the blade speed was about 0.4 m/s, the speed ratio was 1.2, the stroke was 23 mm, and the tooth height was 25 mm. The calculated integrity rate of bud and leaf was 86.89% under these conditions. Finally, the new cutter blade was developed, according to the parameter optimization. The experimental verification was achieved as follows: the integrity rate of bud and leaf was 82.6%, the leakage rate was 0.24%, and the stubble roughness was 2.8 mm, indicating better consistency with the optimized test. The integrity rate of tea picking increased by more than 20% after optimization, indicating the significantly improved quality of tea plucking. The finding can lay a sound foundation for the efficient technology mode of “machine picking and grading” during high-quality tea harvesting. This improved mode can be expected as a broad application prospect in the tea industry. The adaptive optimization of tea varieties and the dynamic process can be used further to promote the plucking tea quality during the reciprocating cutting plucking. [ABSTRACT FROM AUTHOR]

As agricultural labor is decreasing, famous tea production is nearly hard to sustain and is getting more and more expensive in China. To improve the mechanization of tea plucking, this paper designs a self-propelled track-type tea plucking machine that integrates mechanic, hydraulic and electronics. The main parameters of chassis were optimized based on conditions of tea garden. And, three different kinds of cutter blades were designed and analyzed about vibration performance with finite element software. Also, a rigid-flex mixed motion model was established. Based on the model and plots, it is explicit that: 1) the blades move in a sine law; 2) the blades take a symmetrical deform from middle to end while moving; 3) the deformation increases along the blade from the center to sides. The single factor experiment revealed that both travel speed and speed ratio of cutting and travelling had a significant effect on quality indexes (integrity rate, unpicking rate, stubble unevenness) of plucked tea leaf. By universal rotary combination experiment of quadratic regression, the regression equations of three indexes about two experimental factors were established. And, the comprehensive optimization of three indexes was conducted with software Design expert. The optimal operating parameters of machine are as follow: travel speed is 0.41 m/s, speed ratio of cutting and travelling is 1.06; prediction of three indexes are that integrity rate could be reach to 78.26%, unpicking rate reduced to 0.82%, stubble unevenness reduced to 1.30 mm. The results of verification experiment are that: integrity rate could be reach to 77.41%, unpicking rate reduced to 0.87%, stubble unevenness reduced to 1.23 mm. These test indexes that are very close to the predicted values, all surpass the requests specified in the standard of tea plucking with machine. In all, the optimized parameter set is indeed synthetically optimal one that enables the wide use of this tea plucking machine, which can be used in the tea garden that has a lengthways slope less than 18°, a crosswise slope less than 20°, and a height of tea trees between 50-120 cm. From above, the tea plucking machine investigated in this paper provides an effective solution to present tea picking problem that is the bottleneck of tea industry. Further studies need to do for making this machine more automated and intelligent. [ABSTRACT FROM AUTHOR]

China is one of the most important cotton-producing areas in the world. It is well known that cotton stalk is a kind of renewable biomass energy resource and can be widely used. Therefore, it is very important to research the harvesting techniques and equipment of cotton stalk, and design the cutting blade of cotton stalk. The conception of cutting effective rate was put forward on the basis of analyzing the cutting pattern of the reciprocating cutter, and it was used to describe the cutting characteristics of reciprocating cutter, because the cutting pattern of the reciprocating cutter could describe the cutting quality and height of the stubble of cotton stalk. In order to explore the effect of the knife section structural parameters(the width, height, and leading end width of the knife section) as well as the operating parameters(the average cutting velocity was 0.9 m/s, and the ratio of cutting velocity to feeding velocity was 1.25) on cutting effective rate of cotton stalk reciprocating cutter, and optimize the structural parameters of the knife section, the simulation test was performed with the ADAMS software. The simulation testing scheme designed with the box-behnken design(BBD) method was a three-factor three-level testing scheme, and the testing factors were the width of the knife section, the height of the knife section cutting edge, and the width of the leading end. The response surface analysis method was used to analyze the simulation testing data and optimize the knife section structural parameters of the cotton stalk reciprocating cutter. In order to observe and analyze the cutting process and morphological structure of the stubble as well as optimize the profile of the knife section, the cutting test was performed with a cutting test bench of cotton stalk by the high-speed photography technology. The samples were the ripe cotton stalks with the diameter of 11.7-13.2 mm, and the moisture content of 31%-37%, which were collected from a cotton field located at Shanghe County, Shandong Province. The results obtained from the response surface test showed that the effects of the width of the knife section, the height of the knife section cutting edge, and the width of the leading end on the objective value(the cutting effective rate) were significantly different(P<0.01), and the effects of the interactions between the width of the knife section and the height of the knife section cutting edge, between the width of the knife section and the width of the leading end, and between the height of the knife section cutting edge and the width of the leading end on the objective value were also significantly different(P<0.01).By analyzing the sequence images of cutting process of cotton stalk from the cutting test by the high-speed photography technology for cotton stalk, it was known that the effects of the different profile of the leading ends on the cutting quality of cotton stalk and the height of the stubble of cotton stalk were significantly different. It was concluded that the optimal combination of the knife section structural parameters of cotton stalk reciprocating cutter was that the width of knife section was 90 mm, the height of knife section cutting edge was 52 mm, the width of leading end was 15 mm, and the profile of leading end was arc-shaped. On the basis of the results of the verifying tests, it was found that the cutting effect of cotton stalk for cotton stalk reciprocating cutter with the new knife section was good, the height of cotton stalk cutting stubbles of the optimized knife section was 5.9 mm shorter than the standard knife section′s, the average value of cutting power per unit area of cotton stalk for the optimized knife section was 6.1% less than the standard knife section′s, and the smoothness of cutting stubble section of cotton stalk for the optimized knife section was 12% more than the standard knife section′s. The results of this research can provide technical support not only for developing a new cotton stalk cutter, but also for designing the equipment for harvesting hard stalk with a large planting area. [ABSTRACT FROM AUTHOR]

Cutting diagram is an important means of performance analysis of reciprocating cutter. The evaluation of working performance of reciprocating cutter principally depends on the size of 3 featured areas (repeated cutting area, area failing to cut and once cutting area), which can be observed from the cutting diagram. Drawing cutting diagram by the traditional manual tracing method has the disadvantages of low efficiency and imprecise result. Meanwhile the system of cutting diagram drawing and analyzing which is based on the MATLAB and other homemade programs cannot carry on the continuous analysis of parameter. Aiming at the inconvenience of the traditional methods, a cutting diagram analytic system was developed based on visualization platform. This paper took the standard ordinary I type reciprocating cutter as main research object, performed the kinematic analysis to cutting blade and obtained the moving-track curve of featured points. Method to calculate the 3 featured areas was deduced based on the kinematic analysis of the cutting blade. Moreover, 3 special situations which may happen during the calculation process were analyzed, and the respective solution for each situation was proposed. The software was developed based on VISUAL STUDIO 2008. The main interface of this system mainly consists of cutter parameter configuration zone, working property feature analyzing zone and cutting diagram drawing zone. After inputting the cutting parameter by user, system can draw corresponding cutting diagram and calculate the area of featured areas. The drawing of cutting diagram uses Picturebox control and GDI+ (graphics device interface plus) technology, and it can carry on the coordinate conversion to the actual dimension of cutting blade depending on the dimension of drawing zone. In order to adapt the calculation characteristics of computer, it uses the numerical analysis method in calculation process, including obtaining the coordinates of key points through the dichotomy solution to single-variable equation and calculating the area of featured areas by using the trapezoidal method to do definite integral calculation. The main content of working performance analysis is calculating the proportional relationship among the 3 featured areas under different working parameters, thus to find the best working parameters. Traditional method is to carry on comparative analysis by drawing many cutting diagrams, however, it has the shortages of hefty workload and imprecise result. This paper proposed a working performance analytical method depending on stepping calculation, which used the steeping method to automatically calculate and analyze the areas of 3 feature regions according to the cutter dimension parameters specified by users, and generated the corresponding curve graphs in set working parameter range. This provided the basis for users to analyze working properties of cutters and determine the best working parameters. The analysis of the standard ordinary I type reciprocating cutter showed that there was no area failing to cut when the rotator width was less than 44 mm, and no repeated cutting area when the rotator width was greater than 94 mm, moreover, when the rotator width equaled 61 mm, the area proportion of once cutting area reached the highest value which was 88%. Application result showed that the software had the advantages of convenient use, independence of the third platform and precise calculation result, which provided an efficient mean to optimize the operation of the reciprocating cutter. [ABSTRACT FROM AUTHOR]