Bionic Press Device With Profiling Mechanism For Soybean Precision Planter

As one of the most soybean major producers in the word, due to the low level of agricultural modernization, the behindhand technology of mechanized production and the small and scattered production clusters, the soybean production cost of China is much higher than the United States, Brazil and other major producers. The high production cost has been severely restricting the international competitiveness of Chinese soybean. Northeast cold region is one of the biggest soybean production areas in China, so there are great significances to solve a series of problems happened in the development of soybean cultivation in the northeast cold region. It will increase the soybean yield, reduce soybean production cost, enhance the international competitiveness of soybean and ensure national food security. In order to realize soybean production mechanization in the northeast cold region of China, it is necessary to combine agricultural machinery and modern agronomical requirement and develop soybean production equipments under the cultivation technique of double(or more) row ridge. The soybean precision planter is one of the most important equipments to realize soybean production mechanization.Soil compaction after sowing is a key link in the process of seeding operation, and the most simple and effective method to improve the quality of soil compaction is to design an appropriate device for planter. Currently, in the northeast cold region of China, a drill unit soybean precision planter is furnished a press roller which can generally compact two lines at the same time. However, traditional press roller, which does not have the function of horizontal profile, causes an uneven pressure in horizontal direction and different soil physical properties of seedbed easily, and then impacts soybean emergence consistency and soybean yield. In addition, traditional press roller has some problems in the working process, such as big soil adhesion, high slip rate, long longitudinal size and so on. Therefore, it is necessary to develop the press device of soybean precision planter under the cultivation technique of double row ridge in the northeast cold region of China.The bionic press roller with profiling mechanism for soybean precision planter, which is a core component of the press device studied in this paper, whose structure design is divided into two parts to describe: the profiling mechanism and the reducing soil adhesion and anti slip structure. The profiling mechanism has good capacities of vertical and horizontal profile, which can ensure the more uniform pressure. The reducing soil adhesion and anti-slip structure can reduce soil adhesion of roller surface and slip rate to improve the operation quality of press roller.The profiling mechanism adopts the built-in symmetric double-row elastic spokes structure. Through theoretical analysis, ADAMS movement simulation and tests in the soil bin, the order of the factors influenced performances of the profiling mechanism was get: applied load F>stiffness coefficient K>working speed V(working speed V is not a significant factor), the optimal combination of the factors: applied load F=800N, stiffness coefficient K=5N/mm, working speed V=0.5m/s. So the test results and the simulation results are in good agreement. At the same time, the largest amount of vertical profile is 75.9 mm and the largest amount of horizontal profile is 32 °.The reducing soil adhesion and anti slip structure consists of rubber bulges bionic ribs. Through the analysis on movement behavior of the worms in the soil, The reducing soil adhesion and anti slip structure was designed. The orthogonal combining experiment was done in the soil bin. The test results were processed in the Design-Expert software, the order of the factors influenced qualities of soil adhesion was get: rubber bulge height H > rib height L> applied load F; The order of the factors influenced slip rate was get: rib height L > rubber bulge height H > applied load F(applied load F is not a significant factor). At the same time, the optimal combination of the factors: applied load F=450 N, rubber bulge height H=13.9 mm, rib height L =15.1 mm.From Field experiments, the difference of cone index, the quality of soil adhesion and the slip rate in bionic press roller with profiling mechanism(BPR) treatments were separately lower 20.9%, 60.1% and 54.3% than that in traditional press roller(CPR) treatments. The results proved that the optimal combination of BPR was reliable.Field experiments were conducted to investigate the effects of BPR on seedbed properties and soybean emergence compared with CPR under cultivation technique of double row ridge. Under the same experimental conditions, the soil moisture content in BPR1 and BPR2 treatments was higher than that in CPR treatment. The cone index increased with the increase of soil depth. The cone index values in BPR1 and BPR2 treatments were 61.5% and 34.6% higher than that in CPR treatment. Compared with CPR, the higher soil moisture content in BPR1 and BPR2 treatments ensured the lower value of mean emergence time. The highest value of percentage of emergence value and seedling height value appeared in BPR2 treatment, and the lowest value of percentage of emergence and seedling height value appeared in CPR treatment. The good vertical and horizontal profile ability of BPR ensure pressure uniformity in the working process, which produced the better consistency of seedling height. In consequence, the best results of seedbed properties and soybean emergence were obtained from the block with BPR2.According to the practical problems of soybean production in the northeast cold region of China, a bionic press device with profiling mechanism was researched in this paper. The two structures, the built-in symmetric double-row elastic spokes structure and the reducing soil adhesion and anti slip structure, were innovatively put forward, and can effectively resolve the problems of uneven pressure, soil adhesion and high slip rate under the cultivation technique of double row ridge. The bionic press device with profiling mechanism has a new structure and good performance, so it will have good popularizing prospect.