Analysis Of The Dynamic Characteristics Of Vibratory Microtillage Based On Finite Element Simulation Analysis

Handheld Micro tiller is a typical small and medium-sized agricultural machinery,widely used in orchards,greenhouses and various small pieces of land.In the process of farming,there is serious vibration,which reduces the comfort and reliability of the equipment,and even leads to the operator’s white finger disease in serious cases.The research on vibration of micro-tiller focuses on vibration test and simulation analysis of vibration system.The soil cutting process of the knife roller is an important part that affects the dynamic characteristics of the micro-tiller.The coupling of the soil cutting process to the vibration model of the micro-tiller has an important significance.In view of the above problems,this paper has conducted the following research:Based on the LS-DYNA-explicit dynamics software,the soil cutting process was analyzed by SPH particle method,and the average error was 22.93% to verify the correctness of the simulation model.The simulation analysis shows that the speed and vertical cutting force.And the energy distribution of the tool and the soil was extracted and analyzed.It shows that although the rotation speed is positively correlated with the soil kinetic energy,the percentage of the kinetic energy obtained by the soil decreases.With the increase of tillage depth,both the kinetic energy and the percentage of kinetic energy obtained by the soil have increased.It shows that it is not feasible to improve the rotation speed to improve the soil tillage effect,and increasing the tillage depth has positive significance to optimize the soil tillage effect.Secondly,through the method of roller eccentric,realize the vibration rotary tillage,based on the finite element model of SPH particle method,the vibration rotary tillage process under the action of different eccentric distance of the simulation analysis,the results show that the soil cutting force significantly reduced,and the minimum soil cutting resistance at the offset of 0.05 m.Vibration rotary tillage is an effective means to reduce soil cutting resistance.The structure of 1 WGQ 4-70 micro-tiller is simplified,and the soil cutting force based on SPH particle simulation is coupled to the vibration model of the micro-tiller,and the interaction force between the tool and the soil is established,and the vibration characteristics of the micro-tiller are analyzed.The RMS value of the engine and the knife roller vibration is compared with the vibration test,and the error is 27.66% and13.08% respectively,which proves the effectiveness of the vibration model.Then,the vibration model of microtiller is established.Compared with non-vibration rotary tillage,the RMS value of the main components of the tiller increases slightly;but in the range of 0.0.050 m,the RMS value of the offset is0.040 m to 0.060 m.Therefore,in the process of vibration tillage,in order to achieve the best resistance and vibration reduction effect,the value of eccentric should be chosen reasonably selected.