Search

During the tillage of two-way ploughing equipment in rocky and barren soil, due to hard objects such as stones, the plough and the key working parts such as plough column are deformed and broken, thereby reducing the reliability and service life of machines and tools. As such, an anti-overload automatic obstacle avoidance mechanism for two-way ploughing is developed. The maximum obstacle avoidance height is 40 cm, and the obstacle avoidance angle α is designed. The rotation range is 4.6~51.5°, and the effective compression stroke of the spring after pre-tightening is 39.34 mm. The motion equation and quasi-static force equation of the mechanism are established. The ploughing resistance in the equilibrium state is 9.74 KN, and the required spring preload is 9.75 KN. Under the safety factor of 1.3, different spring elastic coefficients change with the rotation angle of the mechanism. The virtual prototype simulation model of the anti-overload automatic obstacle avoidance mechanism is established. The simulation results show that the mechanism can effectively perform the obstacle avoidance action. Bench test verifies that the mechanism can avoid obstacles according to the predetermined load. The field test shows that the stability coefficient of the ploughing depth of the mechanism is less than 8%. The results can effectively realize the obstacle avoidance function and ensure the farming quality, and provide an efficient and reliable anti-overload obstacle avoidance structure and parameter basis for the rocky land. [ABSTRACT FROM AUTHOR]

The accuracy of tractor plowing is an important link to ensure the quality of agricultural crops. The integrated control of draft-position in plowing is an effective plowing precision control technology which can be used to improve the tractor's plowing efficiency. The hydraulic system of the tractor hitch has the characteristics of large load and complex working environment. A differential and integral sliding mode adaptive controller (DI-SMAC) is designed for the tractor hitch hydraulic system with strong nonlinearity, uncertainty and time-varying parameters. Compared with the traditional PID controller, integral sliding mode adaptive controller(I-SMAC) and differential and integral sliding mode adaptive controller (DI-SMAC) in the electro-hydraulic hitch control system, the numerical simulation verifies the advantages of the differential and integral sliding mode adaptive controller. The real test platform of the agricultural tractor is built. The test results show that the DI-SMAC can realize the integrated control function of draft-position. In the position control mode, there is no static error, and the anti-interference ability is strong; Under the draft control mode, compared with the traditional PID controller, the range of traction error of differential and integral sliding mode controller is reduced by 32.9%, and the standard deviation is reduced by 38.6%; When the weight coefficient is changed, the traction force and tillage depth fluctuation are different with different weight coefficients. It is shown that the DI-SMAC is stable and effective, and the developed method is expected to provide technical support for the fine plowing operation of tractors. [ABSTRACT FROM AUTHOR]

The farmland in Xinjiang of China is mainly sandy loam soil, on which the crops are subject to flat planting with mulched film. Before planting, the soil should go through deep ploughing in a short operation period, thus there is high demand on the high-speed plow and it is necessary to optimize the plow based on tillage resistivity to improve its working performance. In view of optimal design of the surface of high-speed reversible plow, simulation test was adopted to optimize the resistivity model, then finite element method was used to test the force condition of the plow. At last, the tillage resistivity of the plow after optimization was tested by soil bin test. Test results showed that, at tilling depth of 300 mm, tilling speed of 12 km/hm, and when the plow height was 250 mm with cutting angle of 37° and dozer angle of 84°, the plow achieved the optimal tillage resistivity and the optimal combination was 2.85 N/cm²; at tilling depth of 300 mm, soil moisture content of 17%, and soil compactness of 220 N/cm², the maximum tensile stress on the surface of the plow was 115.61 MPa and total deformation was 2.869 mm; the maximum flexible strain of the plow was 9.38x10-4. Soil bin test showed that, at tilling depth of 300 mm, dozer angle of 84°, the optimized high-speed reversible plow reduced the tillage resistance by 17.9% compared with common high-speed reversible plow made in China, and can provide reference to the design of high-horsepower tractors. [ABSTRACT FROM AUTHOR]

Straw returning is an effective option to avoid straw open burning during harvest seasons and has been widely implemented all over the world. This study developed a plowing and rotary tillage combined machine, which could bury the straw, break the soil and prepare the soil for planting in one operation. The machine consists of plowing component, rotary component and power transmission system. The plow component was designed by the response surface analysis, which analyzed the influence of different contour line of plow surface on the burying effect and the working resistance at the speeds of 0.8m/s, 1.0m/s and 1.2m/s respectively. In combination with the working effect of the plow component, the rotary blades were arranged by the method of 4n±2. The orthogonal test results showed that the C-plow surface has the best burying effect at 1m/s. The field tests showed that the machine had a straw burying rate of 91%, surface roughness was 0.564, fuel consumption was 43.41 kg/ha and the soil-breaking rate reached 96.08%; all the performance indexes met the design requirements. The study can provide theoretical reference for parameters design of plowing and rotary tillage combined machine. [ABSTRACT FROM AUTHOR]

Soil preparation based on ploughing is a conventional method commonly adopted for cereal cultivation in silty-clay soil. Replacing this method with conservation tillage was the subject of this study based on the evaluation of eight implements used in conventional and conservative tillage. By differently combining the implements, we hypothesized eight methods and assessed the overall energy balance and quality of work for each method. Basing on test results, we proposed an approach to the choice of proper tillage methods, aiming at integrating the benefits of conventional and conservative tillage methods. [ABSTRACT FROM AUTHOR]

The objective of this study was to develop a technique for calculating the resultant force and moment of soil resistance to cutting by the blade of the earlier proposed rotary tillage tool as functions of the rotation angle on the basis of the developed mathematical model of soil-blade interaction. The dependences taking into account the constructive and functional parameters were obtained and analyzed. It was shown that the blade is subjected to repeated loads during the soil cutting, so the equivalent resultant force of soil reactions acting on the blade changes its magnitude, direction and the point of action periodically with changing the rotation angle. The obtained formulas can be used both for carrying out the long-term strength analysis of the rotary tool and for optimizing its constructive and functional parameters. The proposed technique allows to simplify experiments for determining the rotary tool force characteristics and to reduce their number significantly. Thanks to the commonality of the assumptions it can be transferred mainly to other rotary tillage tools. [ABSTRACT FROM AUTHOR]

The conducted researches on a ploughing aggregate, composed according to the "push-pull" scheme as part of the HTZ-16131 tractor with a frontal two-bottom plough and a rear-mounted four-bottom plough, show that there is a positive correlation between the input impact - the turning angle of the driven wheels of the tractor, and the output parameter - its relative bearing. The maximum value of the mutual correlation function between these parameters is quite high, reaching mark 0.88. The researched ploughing aggregate, operating according to the "push-pull" scheme, has satisfactory path indicators. The path variations of the furrow laid by this aggregate are of a low-frequency nature. Arrangement of the supporting wheel of the frontal plough outside the furrow and its movement across an undeveloped agrophone does not lead to the deterioration in the steering ability of the explored ploughing aggregate. [ABSTRACT FROM AUTHOR]

The paper analyses the bending vibrations of a plow blade, modeled as a variable cross-section beam, clamped at one end and free at the other. The study is performed by using the discretization method, while the differential equations of the free vibrations are deduced by means of the influence coefficients method. [ABSTRACT FROM AUTHOR]

This paper presents the calculation of the resistant forces that occur during the deep loosening works in a machine with active organs driven by the quadrilateral mechanism from the tractor PTO. By using the relations for calculating the resistance forces presented in the paper we determined the momentum necessary to drive the plowshares and compare it with the determined experimental values [ABSTRACT FROM AUTHOR]