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A series of 2BMFJ type no-tillage planter has been proposed to serve as a feasible operation mode of “preparation of side-way anti-blocking seed bed and concurrently covered with uniform straw”. The amount of straw mulching can generally determine the effect of straw returning on soil improvement and crop growth benefit. If the amount of straw mulching is too small, there is no obvious effect on the soil moisture conservation and fertilizer cultivation. In this case, it is recommended that the straw can be returned to field in the whole amount. Nevertheless, if the straw mulching is too large, the yield of crop can decline due to “low temperature effect” and “biochemical effect” in some areas with high content of soil organic matter. As such, the proportional straw returning to the field can be used in a straw proportion regulation technology and supporting device under the operation mode of lateral straw cleaning, according to the environmental conditions in soil. The structural parameters of device can be determined using various theoretical analysis. In this study, a multi-link mechanism was designed to control the throwing trace of straw by adjusting the deflection angle of spring-tooth. Two correction coefficients of kx and ky were introduced to the model of straw throwing trace for an accurate simulation. The high speed camera system was selected to in-situ capture the throwing process of straw. The movement and distribution of straw throwing can be achieved, in order to determine the proportion of straw return to field. A cloud map was performed on a Matlab platform, thereby to quantify the distribution of straw. The deflection angle of throwing control baffle and gravity was 45°, when the proportion of straw returning to field was not less than 50%. The field experiment was carried out at the Xiangyang farm of Northeast Agricultural University from October 21 to 22, 2019, where a corn stubble field with the soil hardnessof28.1 kg/m² and soil moisture content of 21.7%. Four factors and five levels quadratic regression orthogonal rotation center combined experimental method can be applied to optimize the influence of various parameters on straw returning proportion, the structure and working parameters in a proportion regulation device. The deflection angle of spring-tooth, area of recovery port, operating speed and straw mulching amount were selected as influencing factors, where as the proportion of straw returning to field were selected as the evaluation index of performance. The test results showed that the area of recovery port and deflection angle of spring-tooth had an extremely significant impact on the test indicators (P<0.01), while the straw mulching amount and operating speed had a secondary impact (0.01

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Non-till farming has attracted increasing attention in developing sustainable agriculture, but the straws and the stubbles left over after harvest could block dispatch of fertilizer and seeds in seed drilling, which could detach the seeds and soil and result in nonuniform seed drilling both vertically and horizontally. Therefore, developing devices able to clean and crush the corn straw on seedbed before fertilization and seed drilling/spraying are demanded. However, the existing blade in such devices for laterally cutting the stubbles cannot completely clean and transport the stubble. The leftovers in soil make seed drilling problematic as they could block seed dispatch, increase energy consumption and, under certain circumstances, even make the sowing device unbale to operate. In order to resolve these problems, we designed a device to laterally cut and remove the stubbles from corn field. In this paper, we analyzed its efficacy in stubble clearance, soil disturbance, energy consumption, as well as conveying and throwing the cut/cleaned stubbles. The optimal structure of the stubble-cleaning blade and the working parameters of the device were calculated by taking the bending angle of the blade α, the transverse cutting edge B, and the angular velocity of the blade ω as determinants, and the stubble clearance ratio, soil disturbance ratio and equivalent energy consumption of the blade as quantitative indexes of its performance, using the three-factor and three-level orthogonal test and the fuzzy comprehensive evaluation method. The results showed that the stubble clearance ratio was significantly impacted by the bending angle, while the performance indexes were significantly impacted by the width and angular velocity of the blade. The factors that affected the performance of the device were ranked in the order of bending angle > transverse cutting edge > angular velocity. It was also found that soil disturbance ratio was mostly impacted by the transverse cutting edge, followed by the bending angle and the angular velocity, while the equivalent energy consumption was mostly affected the transverse cutting edge, followed by the bending angle and the velocity of the cutter tooth angle. The optimized results for the device operation were that when the operation speed was 7.2 km/h, the bending angle was 0.86 rad, the transverse cutting edge was 50 mm, and the angular velocity was 52 rad/s, the associated stubble clearance ratio was 94.3%, soil disturbance ratio was 54.3%, and the equivalent energy consumption was 3.4 kW. Under these conditions, clogging and straw entanglement did not occur. The results in this paper are helpful for designing devices to clear straw and stubbles left over after harvest in no-till farming. [ABSTRACT FROM AUTHOR]

Reasonable planting pattern can increase soybean yield. At present, soybean cultivation models in the cold region of northeast China mainly include conventional ridge planting mode, three row planting pattern on big ridge and four row planting mode on big ridge. The compact planting pattern of big ridge three-row is becoming popularizing gradually. The big ridge three-row reduces the row spacing, increases plant spacing and plant density than the traditional planting pattern. This way of planting soybean increases crop yield by reducing row spacing between soybean plants to increase planting density and to increase the number of plants protected per unit area. The three-row soybean planting pattern means that three rows of soybean are planted evenly on the ridge table of 1.1 m big ridge, and the marginal effect of the ridge platform is fully utilized. The outermost two rows of soybean are 400 mm apart and the spacing of each row of soybean is 200 mm. According to the agronomic requirement and technology for the model of compact planting soybean with three rows on 1.1 m grand ridge, the problem of compact structure and poor passing ability on planting unit are caused by the matching planter that uses single-row planting unit devices in dislocation parallel. The pneumatic cylinder precision seed-metering device for soybean matching compact planting soybean with three rows on 1.1 m grand ridge is designed, combined the features of mechanical clearing and gravitational dropping. The structural parameters of the key components of the three-row soybean seed-metering device on ridge are determined. The diameter of the cylinder is 200 mm, the length of the cylinder is 500 mm, the axial hole of the cylinder is 3 rows and the distance is 200 mm, and the number of single row holes is 40. The sealing problem of the pneumatic cylinder seed-metering device is solved through the innovative design of the structure. In order to effectively remove multiple seeds adsorbed on the hole and keep only one seed in each hole, a scraper seed cleaning device is designed. In order to ensure that the seed can be planted freely in the seeding area, a pressure relief device for isolating the pressure difference inside and outside the hole is designed. In this study, the key structural parameters and the mechanical model of seed-filling process were determined through theoretical analysis. The experiment was employed through the method of quadratic orthogonal rotating center combination of three factors and five levels according to the GB6973-2005 national standard. In test, soybean seed Heinong 48 was selected as experimental material. Combining with extensive pre-experiment and theoretical analysis, the vacuum degree, forward speed and hole diameter were taken as main influencing factors, the seed qualified index, multiple index, missing index and variation coefficient of apiece row seeding mass were taken as response index. The results showed that: the order of the contribution rates on the effect of qualified index was vacuum degree, working speed, hole diameter, the order of the contribution rates on the effect of multiple index was vacuum degree, hole diameter, working speed, the order of the contribution rates on the effect of missing index was vacuum degree, working speed, hole diameter, the order of the contribution rates on the effect of variation coefficient of apiece row seeding mass was, working speed, vacuum degree, hole diameter. The optimal combination of parameters was as follows, the hole diameter was 4.5 mm, the vacuum degree was between 4.7 and 5.9 kPa, the working speed was lower than 9.1 km/h, and under the optimal combinations, the qualified index was not less than 95%, the multiple index was not more than 3%, the missing index was not more than 2%, and the variation coefficient of apiece row seeding mass was not more than 6.5%. The verification test was repeated 10 times on the JPS-12 seed-metering test beds, the results were indicated that the actual test results were in agreement with the optimization results. The results of the research laid a foundation for the development of pneumatic cylinder grand ridge three-row seed-metering device for soybean, and provided a reference for the research of soybean narrow-row and flat-dense planter. [ABSTRACT FROM AUTHOR]