Research And Design Of Camellia Oleifera Fruit Harvesting Equipment With Simple Structure And High Efficiency

At present,most of the fruit harvesting machinery on the market is large-scale machinery produced abroad.This kind of machinery is not suitable for orchards in China because of its large requirement of tree row spacing,high price and lack of applicability.In China,there are few people engaged in mechanized harvesting of fruits,and the research on harvesting device is not mature.In response to this situation,with the goal of improving the efficiency and applicability of harvesting equipment,a set of Camellia oleifera fruit picking machine and collecting machine were designed.The main contents of the paper are as below:(1)According to the design requirements of the Camellia oleifera fruit harvesting machine,it is determined that the inverted umbrella-shaped collecting and the hand-held comb picking method are combined to harvest the fruit.Field measurements have obtained the average plant spacing,plant height and crown width of Camellia oleifera,which will provide reference for the design of harvesting equipment.Choosing the mobile platform,determining the angle of the inverted umbrella,and the picking method of the picker will lay the foundation for the following design.(2)The self-propelled loading truck was modified as the mobile platform of the collector.The unfolding mechanism composed of the front rotating rod and the middle rotating rod was designed,and the impact force generated when the fruit fell was calculated.By finite element simulation,the stress,strain,and displacement diagrams of the rods during harvesting were obtained,and the dynamic simulation of the transmission system composed of rack and pinion verified the rationality of the design.(3)Designed a control system that can remotely control the walking and turning of the collector,and expand and raise the collecting surface.According to the hydraulic schematic diagram,the components are selected,and the hydraulic system is simulated by AMESim software.The simulation results show that the working pressure of the lifting hydraulic cylinder is 3.2MPa,the flow rate is 11.8L/min,and the unfolding hydraulic cylinder can move in place within 2s.(4)According to the design requirements of the picking machine,the comb-brushing fruit picking machine was designed.The hand-held sucker rod and the whole machine are analyzed by the finite element method.The simulated natural frequency of the handheld rod and the whole machine are both greater than the external excitation frequency,and no resonance occurs during operation.The modal test results show that the model is accurate,and the analysis results are more consistent with the modal test and the modes of each order are more consistent,indicating that the built handheld machine model can reflect the inherent vibration characteristics of the whole machine.The finite element model is valid.(5)The Camellia oleifera fruit harvesting equipment were built and assembled.The collecting machine worked well under complex terrain.It can walk and turn under remote control.The average time to unfold the collecting surface is about 2s.It can completely surround the tree and form an inverted umbrella-shaped collecting surface.The picking machine can complete harvesting a Camellia oleifera tree in less than 6minutes,with an average recovery rate of 93.3%.The damage rate to flower buds and stamens is 9.2% and 13.3%,respectively,and the picking efficiency is twice that of manual way,which meets the design requirements.