Vibratory Harvesting Mechanism for Tree Fruit Based on Epitrochoid

Abstract:

To further improve the efficiency of vibratory harvesting on tree fruit and reduce the mechanical damage on tree body, a hypothesis about ideal fruit tree excitation pattern was put forward based on the working principle of vibratory harvesting mechanism. The influence of different kinds of displacement patterns on vibratory fruit harvesting was simulated based on finite element software (ANSYS). According to the simulation results, a vibratory fruit harvesting mechanism was designed based on planetary gear train to generate epitrochoid trajectory. Then, its characteristics and working principle were analyzed and its kinematics model was established to derive the equations of vibratory displacement and acceleration amplitude. By meeting the requirement of displacement and acceleration amplitude, main parameters of the epitrochoid mechanism were optimized based on the parameterguided optimization algorithm. A prototype of vibratory harvesting mechanism for fruit tree was manufactured and its trajectory was recorded by highspeed photography system. Trajectories of experiment, theoretical analysis and virtual simulation were consistent, which verified the design of this harvesting mechanism. A dynamic response test of one fruit tree sample was carried out in lab. Statistics results on the mean value and standard deviation of the maximum synthesized acceleration of the test points on the tree sample confirmed that the epitrochoid mechanism could stimulated the fruit tree effectively.