Numerical Simulation Study on the System Dynamics of Sea Buckthorn Harvester

To investigate the mechanical characteristics of the vibrational air-sucking sea buckthorn harvester, a system dynamics model integrating the harvester and the sea buckthorn tree was developed in this study.The model incorporates the adsorption force of the sucking device and the mechanical interactions between branches and fruits.Through numerical simulations, the influence of excitation frequency, lifting height, vibration isolation spring stiffness, crank radius, and adsorption force on the displacement of each component in the vibration system was systematically analyzed.Unlike vibration-only or suction-only prototypes, the proposed model simultaneously incorporates vibratory excitation and vacuum suction, which yields a 15 % higher detachment rate at 25 % lower trunk acceleration, thereby mitigating tree damage.The dynamic analysis demonstrates the vibration displacement of all components peaks at an excitation frequency of 10 rad/s.Increasing the stiffness of vibration isolation springs enhances the harvester's anti-vibration performance while amplifying the relative displacement between the tree trunk, branches, and fruits.Notably, the lifting height exhibits minimal impact on the harvest rate, whereas enlarging the crank radius significantly increases vibration displacement.Additionally, the application of adsorption force promotes fruit detachment by augmenting vibrational amplitude.This study provides theoretical insights for optimizing the design of vibration-adsorption combined harvesters.