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The reciprocating cutting system is one of the key parts of a tea harvester; and its cutting performance directly determines the cutting power consumption and harvesting quality of the machine. Because the structural parameters of reciprocating cutting systems do not match the tea cut; resulting in larger cutting resistance, it is necessary to optimize the structural parameters. The cricket mouth part has outstanding performance in tea tree fiber cutting; and the curved structural characteristics of the upper jaw of the cricket have been useful to improve the cutting efficiency of cutting system. Quantitative analysis of the structure of the upper jaw revealed that the arc-shaped structure of the incisor lobe would inspire new bionic blades and bionic cutters to solve the above problems. The cutting performance experiment of the cutting blade was designed for investigating the effects of inter-node number; tea variety and blade type (ordinary blade; bionic blade e and bionic blade f) on the cutting force and cutting power consumption. Experimental results of cutting performance have shown that the bionic blade could reduce cutting resistance and cutting power consumption. Tea varieties had little effect on cutting force and cutting power consumption. In addition, the orthogonal test was carried out to study the influence of cutter type with the cutting speed ratio and cutting angle on the integrity rate and missing rate of tea shoot. The field cutting experiment showed that the cutting angle was the most important for the integrity rate and missing rate of tea shoot; followed by the cutter speed ratio; and finally, the cutter type. The optimum combination of parameters was a cutting speed of 0.8 m/s; a forward speed of 1.0 m/s; a cutting angle of −3°, and using the bionic cutter e. With the optimal parameter combination, the integrity rate and missing rate of the tea shoot were 92.7% and 3.9%, which were increased by 13.2% and decreased by 6.4% compared to those under the condition of the 0° cutting angle and an ordinary cutter. As a result, the bionic cutter could obviously reduce cutting resistance; reduce cutting power consumption and improve the harvesting quality. These results would provide guidance for the design of the reciprocating cutting system of tea harvesters and other stalk cutting machinery. [ABSTRACT FROM AUTHOR]

Vegetable production is facing the problems of low resource utilization rate and serious environmental pollution. Vegetable sowing and planting with fertilizer have the characteristics of extensive and low efficiency. An intelligent monitoring system of vegetable fertilization and seeding is designed in this paper. The system uses CAN bus communication protocol to collect sensor signals and PLC to control the execution part. The seeding and fertilization monitoring were carried out by photoelectric sensing technology and piezoelectric thin film technology, respectively. The system is composed of sowing and fertilizing machinery, monitoring system of seed leakage, alarm system of fertilizer blockage, variable-rate fertilization control system and on-board computer. The system uses the GPS module to get the location information of the machine. Combined with the pre-loaded plots map of soil prescription, the target fertilization amount in the current position is determined. Pressure sensor and microcomputer control are used to calculate the current fertilization rate and flow information, and the fertilization rate is adjusted in real time according to the moving speed of the machine. Finally, the detection of miss-seeding, blocking and precision fertilization is realized. The field test results show that the accuracy of monitoring is over 91%. The alarm error of fertilizer blockage is less than 4%. The accuracy of variable fertilization is more than 94%. The whole machine monitoring system can adapt to complex field environment and has better practicability and economy. [ABSTRACT FROM AUTHOR]

The new cleaning system, mainly composed of light impurities cleaning device and stems separating device was designed. The former used cross-flow fan to clean light impurities, and the latter used the differences of radial geometry size between peanut pods and stems to separate stems from peanut pods. By means of theoretical calculation and graphic analysis, the structure motion parameters of the main working parts were determined and the performance experiments were carried out. According to the experimental results, the influence law of the structure motion parameters of peanut cleaning system on cleaning performance was analyzed and optimal combination of parameters was obtained. When the rotation speed of cross-flow fan was 920 r/min, the distance between sliding screen and fan impeller was 100mm, and the width of discharging exit was 50 mm, the clearance of separation rollers was 2mm, the rotation speed of separation roller was 300 r/min, and the angle between separating device and horizontal plane was 35°, the impurity content was 0.89%, and the cleaning loss rate was 0.62%, which met the requirement of peanut harvester. [ABSTRACT FROM AUTHOR]

• Design a high-speed and precise seeding control system for rice seedlings, and develop human–computer interaction software. • The dual position feedback adjustment (DPFA) method is used to improve the high-speed sowing effect of rice pot seedlings. • Use fuzzy PID to optimize the control system to improve system response time, speed regulation accuracy and robustness. • Explore the changing rules of seeding effect and verify the effectiveness of the control system based on DPFA. To improve the alignment accuracy of the mechanical drum-type rice bowl seedling raising precision seeding line under the high-speed sowing operation state between the seed outlet and the bowl hole. This paper proposes a high-speed and precise positioning seeding control system for rice seedlings based on dual position feedback adjustment (DPFA). Based on Siemens PLC controller, through sensor selection and installation, controller parameter acquisition and calculation, and human–computer interaction software development. We have completed the design of the high-speed and precise alignment seeding control system for rice pot seedlings. Realize the dual position detection of the mechanical drum-type seed wheel and the 406-hole tray. Applying the fuzzy PID controller optimized the dual-position feedback regulation rice pot seedling high-speed and precise alignment planting control system. The response time was shortened to 0.0432 s, the overshoot was 4.5 %, and the adjustment time was 0.1105 s. The sowing test was conducted with sowing speed and height as the main influencing factors and sowing uniformity, leakage rate, and sowing pass rate as the evaluation indexes. The test results show that the sowing speed is within 500 trays/h ∼ 600 trays/h, the sowing uniformity is higher than 65 %, the missed seeding rate is less than 1.5 %, and the qualified rate of sowing is above 94 %. Among them, the maximum sowing uniformity was 66.27 %, the minimum value of missing seeding was 0.89 %, and the sowing qualification rate was 97.06 %. The accuracy rate of material shortage alarms is 100 %. The DPFA-based high-speed and precise alignment sowing control system for rice pot seedlings can realize the exact alignment control function of the mechanical drum-type seedling raising and sowing line. [ABSTRACT FROM AUTHOR]