| Conservation tillage is the background of design and reserch with modern agricultural equipment and will also become the inevitable trend, subsoiling is a crucial ring in the protection cultivation. There are some problems with the deep tillage machines such as operating efficiency low, large power consumption and intelligent degree low. It has already become the focus of agricultural machinery engineering research how to reduce energy consumption and implement intelligent control for the deep loosening machine as largest energy consumption in dry land farming. In order to reduce the running resistance of the deep loosening machine and to improve the intelligent level of the machine, theoretical analysis and practice is put into effect in this paper, and that relying on the National Natural Science Foundation of China, "the broken soil mechanism and drag reduction optimization of the self excitation vibration subsoiler". The vibration theory was applied to the soil cutting process of the deep loosening machine, and the mechanism of reducing the resistance of vibration was excavated by simulation, theoretical analysis and experiment, and the optimization model was built. The finite element method was applicable to study the soil cutting process aiming at the specific cohesive soil, the finite element simulation technique is used to carry out the numerical simulation.More details about the research are as follows:(1) Study on drag reduction and testing technology of deep looseningThe application of deep loosening reduction technology was studied, the problem of soil cutting with finite element method was analyzied and the online monitoring device of agricultural machinery and equipment was researched based on the research status and development trend of deep loose drag reduction and testing technology at home and abroad. Research shows, compared with other drag reduction methods, the vibration type of deep loose drag reduction is not required to be added with other auxiliary devices, which is easy to operate and has great prospects and space for the improvement of drag reduction effect; Online monitoring equipment research and development in China has just started, but the demand is great, in addition to the CAN bus communication technology in agricultural machinery and equipment has a more broad prospects for development; Finite element method simulation of soil cutting has been successfully used in many engineering fields, in the agricultural machinery research it has also commonly used to make parts of the static stress analysis and the application was scarced in vibration subsoiling process simulation, but it has the trend of development.(2) Study on the mechanism of vibration deep loosening soil and the reduction of resistanceThe vibration subsoiling drag reduction mechanism was analyzed, the structure and working principle of vibrating subsoiler was studied, and in the trial soil slot were studied in the experiment in soil cutting machine subsoiling using five rod force measuring device. Through the single factor experiment of three factors, the vibration frequency, amplitude of vibration and the advance speed of the machine tool, the correlation between the two factors was analyzed. The experimental results showed that the cutting resistance of the vibration mode was less than that of the non vibrating process, but the total power consumption was greater than the total power consumption in the process of the deep loosening.(3) Motion characteristics analysis and Simulation Research of vibration deep loosening machineFrom the vibrating subsoiling machine trajectory and the motion characteristics, it was obtained through qualitative research and quantitative research to determine the vibrating subsoiling machine vibration mechanism of drag reduction, and the vibration mechanism of UG modeling was constructed and motion simulation was analyzed. The experimental results show that the structural parameters of vibration type deep loosening machine-vibration angle has a great influence on the drag reduction. When the vibration angle is negative, the motion trajectory of the deep loosening shovel is more conducive to reducing the resistance; At this time, the unit vibration period of the deep loosening process can be split cutting, backward and after three stage, different shovel ratio configurations will largely influence trajectory. When the shovel ratio is less than 1, subsoiler is continuous cutting operation, reducing the resistance effect is the best. The results above analysis were verified with UG motion simulation analysis, and the load data was storaged for the finite element simulation of soil cutting process.(4) Finite element modeling of soil cutting process of deep loosening machineIn the foundation of UG motion simulation and ANSYS/LS-DYNA finite element technology, soil mechanics parameters were analyzed that related to the effects of soil tillage resistance and quality, soil parameters were determined. The process was put into practice for researching the effects of subsoiling soil cutting machine with the finite element simulation method. The experimental results show that the simulation model was effective and feasible; The force with deep loosening shovel in non vibrating subsoiling was larger, and mainly concentrated and shovel handle and blade tip junction, stress decreased significantly in vibrating subsoiling, and present state of fluctuation, and the corresponding soil stress has become wave trends in machine direction of radiation. This phenomenon is conducive to soil loose and broken, reduce the power consumption of the equipment in the process.(5) Design and test of the on-line monitoring system of vibratING SUBSOILERAccording to the design requirements, the hardware and software of on-line monitoring system with the vibration type deep loosening machine were designed according to the principle of the five strokes, and the corresponding test experiment was carried out. Experimental results show that the maximum absolute error was 5% and accuracy was 0.1% in 11 road AD detection circuit experiment, and it was designed to detect the sensor signal, transmit information, send the operation parameters and the position of the subsoiling operation plots with GPS by GPRS, and other functions. The device could be used in the field or laboratory research and implement long-term job parameter detection.(6) Study on the field experiment of vibrating deep loosening machineThrough the method of variance analysis, orthogonal design and field experiment, the influence of the tillage resistance was studied that include the forward speedVo, amplitude a= R sin s and vibration angle. Test results show that test equipment working resistance reached the minimum value of 3.975kN when t he advance speed of the machine was 0.75m/s, vibration amplitude was 7.5mm and vibration angle was-150. According to the optimization results, the structure of the vibrating type deep loosening machine was reformed, and the field experiment was carried out with the improved equipment and developed on line monitoring equipment. The results showed that the density of the soil decreased by 3.11%, and the soil firmness decreased by 0.67kPa, and the tillage resistance decreased by 9.45% after the parameter optimization. |
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