Mechanization in agriculture & Conserving of the resources
Vol. 69 (2025), Issue 4, pg(s) 95-98

MECHANIZATION IN AGRICULTURE

Modeling the Shaking Process of a Walnut Tree:

  • 1 Technical University of Moldova

Abstract

The results of a study of the shaking process of a walnut tree are presented. Shakers used in harvesting machines are specialized equipment that is attached to the tree trunk and generates controlled vibrations, causing the fruit to fall to the ground or into special catching devices. Thus, universal shakers for various types of nuts, including walnuts, almonds and hazelnuts, ensure fast and uniform harvesting without significant damage to the trees. When harvesting nuts by shaking, the dynamic properties of the trees are important. Therefore, it is necessary to calculate the natural frequency of the system’s oscillations, and it plays a key role in the occurrence of the resonance effect.Thus, during the shaking process, the natural frequency of the system includes the tree and other elements interacting with it, which makes it possible to determine the optimal operating modes of the vibrators to ensure the required completeness of fruit removal with the least energy expenditure. For this purpose, the Euler-Bernoulli theory is used, according to which, when solving a dynamic equation for specific fastening conditions, the natural frequencies and corresponding vibration modes are determined, at which the beam oscillates without external forces.

Keywords

References

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