Abstract:In order to improve the uniformity of fruit tree vibration harvesting response and the fruit harvesting efficiency, and to reduce energy consumption and the damage of fruit trees and fruits, a dual body multidirectional device was designed in this study. The device was mainly composed of eccentric blocks, transmission gears, transmission shafts and boxes. With establishment of the vibration device-fruit tree vibration system the multidirectional load effects produced by the combination of six different eccentric block speed ratios and eccentric moment ratios were analyzed. Firstly, three-dimensional models of fruit trees were obtained by using multi-view three-dimensional reconstruction technology. Then, the harmonic response of fruit trees were analyzed using ANSYS to find out the optimal working frequency of the excitation device. Finally, ADAMS was used to set the dynamic simulation model of fruit tree, and comparatively analysis of the acceleration response of fruit tree under the multidirectional load, linear load and circumferential load. The simulation results showed that with the speed ratio of two eccentric blocks 3∶1 and the ratio of eccentric moment 1∶1, the average acceleration response of fruit trees under the multidirectional load was 194.35 m/s2, which was higher than that under linear load(186.28 m/s2) and slightly lower than that under circumferential load(204.41 m/s2). The coefficient of variation of acceleration response for multidirectional load was 0.575, which was lower than linear load(0.625) and circumferential load(0.622), indicating that multidirectional load had a more uniform acceleration response. Field experiments showed that the harvesting efficiency of the device was 92.2%, and the fruit damage rate was 4.6%, showing better performace over the single eccentric vibration device.