Study On Vibration Characteristics Of The Oil Camellia Fruit Picking Machine

In order to adapt to the rapid development of camellia oils industry and improve the harvesting efficiency of oil camellia fruit in China, it needs the deeper study of oil camellia fruit automatic picking equipment. This paper studied on vibration characteristics of the oil camellia fruit picking machine which was newly designed, and according to the relevant vibration characteristics and parameters obtained, researched whether the design of picking machine was reasonable and guided to optimize and improve the design of picking machine, thus made device structure and dynamic performance more perfect, and avoided resonance when the exciting frequency was close to the natural frequency of picking machine. The paper mainly includes the contents as follows:(1) The structure characteristics of oil camellia fruit picking machine was introduced, and the 3-D model of oil camellia fruit picking machine was built by computer aided design software Pro/E.(2) The finite element model of frame structure was built by ANSYS Workbench, then performed its model analysis and harmonic analysis. On the basis of the analyses, we could find out that the whole rigidity of frame structure was fine, and the structure design was reasonable. Frame structure could avoid the resonance frequency effectively. Vibration of picking arm mounting surface was inconspicuous by the harmonic loads, so frame structure would not cause too much effect on positioning accuracy of picking arm.(3) The finite element model of arm frame was built by ANSYS Workbench, three kinds of typical pose were selected, then its model analysis and modal matching analyses were performed. According to the results of modal analysis, we could find out that the natural frequency of arm frame was much higher than excitation frequency, so resonance phenomenon would not happen. Furthermore, the weak parts of arm frame were found out and relative improving suggestion was put forward. Through modal matching analyses, local resonance region was found out, and structural design was improved, thus the problems were solved.(4) The finite element model of picking head was built by ANSYS Workbench, then its model analysis was performed. According to the results of modal analysis, we could find out that the first natural frequency of picking head was close to work frequency, so it was possible to have a resonance. In order to solve this problem, the structure was optimized by Orthogonal Experiment Method, Neural Networks and BP Genetic Algorithm, as a result, the first natural frequency was improved, the optimization achieved the purpose of avoiding the resonance frequency.(5) According to the working principle of picking machine, applied vibration theory to build mathematical model of picking machine, and derived the differential equations, then analysed the influence of different parameters on the response by MATLAB and found out the size of the response frequency.This research shows that:From the standpoint of study on vibration characteristics, the design of picking machine is basically reasonable, as for the individual problem, it could be solved effectively by the methods adopted in this paper, thus the structure design could meet the design requirements. At the same time, this paper could also be an effective reference for the subsequent research and similar mechanical research.