No abstract

In China, low degree of automation seriously affects the working efficiency and quality in vegetable transplanting. As one of the most important vegetables in China even in the world, tomato was taken as the research object in this study. An automatic single-row transplanting device was designed, based on the statistical analysis of the physical and mechanical properties of tomato seedlings of a typical variety. Based on the technology of mechatronics, the device integrated the functions of transporting seedling tray, automatic seedling extraction and mechanical planting. The kinematics orthogonality solution combined with the dynamic sequence solution method was used to optimize and analyze the kinematic parameters of the automatic seeding mechanism, and the "sickle" trajectory was obtained. According to the position and movement requirement for taking and dropping seedling, the mechanical conditions and the working parameters of key execution parts were obtained by using analytic drawing method to analyze the mechanical condition of seedling collecting mechanism. The transplanting experiment was conducted at room temperature of 25°C, and the age and moisture content of the seedlings were 40 d and 55%, respectively. The results showed that the highest success rate was 92.59%, and the lowest rate of leakage was 23.13%, when the transplanting frequency was 60 plants/min. The lowest success rate was 77.78%, and the highest rate of leakage was 38.75%, when transplanting frequency was 120 plants/min. When the transplanting frequency is between 60-90 plants/min, the device can meet the requirement of high speed transplanting for potted vegetable seedling.

No abstract

No abstract

In order to improve the efficiency and quality of transplanting vegetables in dry land, based on the seedling technology, transplanting effect and analysis of the planting process, a potted vegetable seedlings transplanting machine was designed. It mainly comprised rotary disc type feeding mechanism, five-bar duckbill type planting mechanism (simulated duckbill mechanism, disc cam, connecting rod, crank, fork, cable) and power transmission system. Based on the physical parameters of the seedlings and design requirements, it was determined that the diameter of the duckbill was D=90 mm, the opening and closing angle was 25°, and the taper angle was 17°. A test bench with adjustable parameters was built by analyzing the structure of the planting mechanism and the motion of the working process. The digital speckle technique was used to optimize the parameters, so that the length of the crankshaft Ι was S 1 =100 mm, the length of the crankshaft ΙΙ was S 2 = 80 mm, the length of the connecting rod Ι was S 3 =140 mm, the length of the connecting rod ΙΙ was S 4 =260 mm, the length of rod to connecting the rack was S 6 =314 mm, and the height of planting track was H=450 mm. According to the above parameters and the control requirements of the duckbill mechanism, the cam stroke was determined to be S=15 mm. And the initial phase difference between the two cams was 180°. The experiment was carried out with pepper seedlings as transplanting objects. The results showed that when the planting frequency was 50-70 plants/min, the seedling upright rate was 93%-91.1%, the planting depth qualified rate was 96%-92%. The leakage rate was 0-0.26%, the variation coefficient of plant spacing was 0.37%-0.67%, the injury rate was 0%, and the mechanical damage degree of the mining surface was 2.43-3.77 mm/m 2. The machine can effectively improve the quality of transplanting, which can meet the production needs and design requirements of the mechanism.