Dynamic Simulation Of Ridge-Till And No-Till Planter And Parameter Optimization About Key Parts

In Northeast ridge-zone of China, the temperature is low, and wind erosion and spring drought are serious. The main crop is corn, and the main form of tillage method is ridge-till. Maize is a crop that for a year, its growth cycle is long and straw and stubble are stout, which proposed higher requirements for the performance of no-till planter when working on the uncultivated land next year. No-till planter is core equipment of the protective tillage, so it is necessary to conduct theoretical analysis, parameter optimization and performance experimental study on its key parts. Additionally, it has important theoretical and practical significance for improving the quality of no tillage planter, promoting conservation tillage technology and guaranteeing the sustainable development of agriculture.The topic of this paper is from the National Natural Science Foundation of China (51275318):"Study on working mechanism and parameter optimization of mechanical no-till seeding and cutting device". Based on the analysis and summary of the existing no-till planters at home and abroad, this paper analyzed the longitudinal vertical plane stability of 2BG-2 type corn ridge-till and no-till planter, optimized the cutting and blocking device, established the dynamic model of the cutting and anti-blocking device, developed a new profiling mechanism configured a spring and damper and compared with the original profiling loading mechanism of no-till planter. The main conclusions are as following:(1) Forces model of the planter unit was studied, mathematical model of change of the seeding depth stability was established, and according to this model, computer simulations were conducted to study the related factors affecting seeding. It provided valuable information for the development and improvement of no-till planter in the Northeast ridge zone in China.(2) A kind of cutting and anti-blocking device with two cutting modes was improved, the study solved the phenomenon of double-disc blocking in the field work, avoided the defect of the slip surface of disc Coulter. Through two factors and three levels of orthogonal test, effects of the operation speed and weight of the stubble on cutting depth and traction resistance were studied, variation of the stubble breaking depth and traction resistance with change of the operating speed and weight of the change was obtained, the primary and secondary sequence of the influence of the factors on the depth and the traction resistance was obtained, in addition, optimum field operation parameters of the cutting and anti-blocking device were obtained.(3) The form and working principle of the existing tillage planter profiling mechanism was analyzed, and the structure and size of profiling mechanism meeting the requirements was determined. On this basis, the spring damping device was arranged on the parallel four-linkage profiling mechanism, and three dimensional solid model of planter unit with parallel four-linkage profiling mechanism is established using SolidWorks software.(4) The system transfer functions which the change of the depth of the stubble as input and the drag force as output were established, when the cutting and blocking device worked in the field. In addition, the input and output signals were analyzed in time domain and spectral density. According to the field work condition of no-till planter, the information model of no-till planter with was analyzed, and the related theory of the transfer function of it was studied. Transfer functions for no-till planter monomer system installed two different profile loading mechanism were established, and the dynamic stability of the system and the unit step response curve were studied. The results showed that no-till planter system installed two different profile loading mechanism was under damping attenuation vibration system, and the damping ratios were 0.62 and 0.56 respectively, which indicated that the design of the new mechanism was more reasonable. Study of unit step response curve of the two system transfer function showed that:compared the no-till planter system with new profile loading mechanism to the original one, system rise time and peak time increased slightly, but the system response time and the maximum overshoot were reduced by 18%and 32%, therefore, the system was stable and good.