Simulation And Experimental Research Of Micro-power Tiller Frame’s Vibration Characteristics

The main terrain of the southwest China is mountainous and hills. The complex terrain is difficult to cultivate. The arable land is small and scattered in there, even though the southwest region is one of the most important rice production place of China. So it is urgent to improve agricultural mechanized levels. Currently, micro-power tiller is the main machine for cultivating in hilly terrain, because it is convenient and lightweight. At the same time, micro-power tiller is simple to use. Most of the tillers are able to meet the basic requirements at this stage in China, but the strong vibration and noise bring greatly physical and psychological harm to the operator while working. The production efficiency is dropped for this reason. Therefore, how to solve the vibration and noise problems when tillers are at work is the key factor of tillers’development. While it is a key point to achieve agricultural mechanization and to improve production efficiency.In this paper, a common type tiller in Chongqing is chosen to research its vibration theory. According to the requirements for analyzing and building the FEM model, the tiller is divided into several parts as key components, such as frame, gearbox, engine and knife rolls, etc. Then the components were modeled by UG to import ANSYS for the next simulation analysis. This article focuses on the analysis of vibration characteristics of the micro-power tiller’s frame. First of all simplify the gearbox, engine, knife rolls and other component to model3D geometric models in UG of the frame, the handle of frame, engine bracket and other key parts. Second we build their FEM models in ANSYS Workbench, and analysis their unconstrained modal respectively. So we can get the natural frequency and modes of them. Then we use the LMS Test. Lab to do experimental modal testing, and get the experimental modal result like their natural frequencies and mode shapes, etc. of the frame’s handle and engine bracket. While the result of the experimental modal and simulation results can be compared to verify the validity of the FEM models for adjusting and optimizing the model. Well the FEM models were right though comparing the two results. Finally, we got the main vibration source by comparing the vibration characteristics of the frame and other parts of the micro-power tiller: one is from the engine; another is from the knife rolls. They can also cause resonant with the frame. So we can strengthen the stiffness of the frame to avoid resonant. At the same time, we can install some vibration isolation equipment to reduce the vibration from the engine and knife rolls.