INVESTIGATION INTO VIBRATION BEHAVIOR OF THE INTEGRATED SHALLOT HARVESTER

The study investigates the vibration dynamics of the integrated shallot harvesting machine to support design refinement, aiming to improve operational efficiency, harvesting performance, and packaging for transportation. The investigation is based on an existing integrated machine developed under a Vietnamese State-Level Scientific Research Project. A dynamic model with 17 degrees of freedom was developed to comprehensively represent the system’s motion, including the tractor, harvester, harvesting head, coupling joint, and eight wheels. Nonlinear soil characteristics were modeled using the Bekker terrain model, with specific soil parameters measured in Vietnam fields. Simulation results show notable vibrations in the integrated shallot harvesting machine and the harvesting head. At the beginning of the harvesting phase, the head experiences large amplitudes and high accelerations, which may damage shallot bulbs. The study proposes technical solutions such as optimizing damping coefficients, adjusting system stiffness, or incorporating active control systems to maintain stable harvesting depth and improve harvesting quality. The results provide a foundation for further refinement of integrated shallot harvesting machine design.