Optimal design and experiment on vibratory fruit harvesting mechanism with three-dimensional excitation

Abstract: With the growth of orchard area and fruit yield in recent years, it is still a big problem for farmers to harvest fruit efficiently in China. Because the shaking-type harvester can make mature fruit detached quickly and effectively, the existing fruit harvesters are mostly shaking type, but the efficiency of shaking-type harvester is not good enough, the effect of various dimensional excitations on fruit tree was discussed in this paper. After comparing the distribution of acceleration responses on the fruit tree by simulation under different kinds of excitation, a three-dimensional excitation method was proposed and the vibratory harvesting mechanism with three-dimensional effect was designed. Then the kinematics of the mechanism was analyzed, and major parameters of the component dimension were optimized based on the genetic algorithm. Finally, the prototype of this mechanism was built according to the optimization results. A tree was tested to compare the excitation provided by the prototype and an eccentric vibration motor, which is to inspect the effect of these two shaking methods. Results show that it had a smaller variation coefficient when the tree was excited by the three-dimensional vibratory harvester, which means it may take less time to excite all branches into a certain vibration when using the three-dimensional vibratory harvester, thus the harvesting efficiency can be improved.