Design And Experiment Of Portable Camellia Fruit Layered Harvesting Device

The distance between rows of horticultural cultivated Camellia was small,so it was difficult for the current development of Camellia fruit picking machinery to work in the Camellia forest.For this reason,an portable Camellia fruit layered harvesting device was designed.In order to reduce the damage rate of flower bud during mechanical picking of Camellia fruit,an innovative layer mechanism was designed.The principle of picked fruit branches in layers was analyzed.ANSYS Workbench was used to simulate the stress of Camellia branches under the action of layer mechanism and layer picking device.In order to improve the picking efficiency and shorten the running time of the layer mechanism,the layer mechanism was optimized in ADAMS.In Creo6.0,a three-dimensional model of portable Camellia fruit layered picking device was established.Based on the simulation analysis,two generations of physical prototypes were developed.The experiment was conducted in Camellia planting base of Jiangxi Academy of Forestry Sciences.The main results of this paper are as follows:(1)In order to reduce damage to Camellia bud during mechanical picking of Camellia fruit,the principle of layer picked was innovatively put forward in this paper,and the entry conditions of layer mechanism were analyzed.Through the theoretical analysis of the simplified model of the interaction between the layer mechanism and the fruit branch,it was known that the comprehensive normal stress and shear stress of the fruit branch increased with the increase of the distance between the layering rubber roller.Through the theoretical analysis of the simplified model of the interaction between the layer picking device and the fruit branch,it was found that the comprehensive normal stress and shear stress of the fruit branch increased with the decrease of the rubber roller clearance.(2)In ANSYS Workbench,the finite element model of the interaction between layer mechanism and fruit branches,and the finite element model of the interaction between layer picking device and fruit branches were established respectively.Stress simulation results showed that : when the fruit branch interacted with the layer mechanism,the maximum normal stress of the fruit branch was 11.3MPa,which was less than 26.44 MPa of the verification test,the maximum shear stress of fruit branch was 0.78 MPa,which was less than 9.02 MPa of verification test;when the fruit branch interacted with the layer picking device,the maximum normal stress and the maximum shear stress of the fruit branch were 0.75 MPa and 0.44 MPa,which were less than the verification test values.The feasibility of layer picking was verified.In order to shorten the running time of the layer mechanism and improve the picking efficiency,the layer mechanism was optimized in ADAMS.The optimization results showed that the running time is shortened by 1.9s when the same distance of layering rubber roller was360 mm.(3)According to the row spacing of Camellia forest and the height range of Camellia fruit distribution,the overall structure of the portable Camellia fruit layered harvesting device were determined.In order to enhance the working reliability of the picking device,a hydraulic motor was used to drive the picking head.In order to meet the needs of Camellia fruit picking test,a oil inlet throttle speed control loop was designed to control the speed of hydraulic motor by adjusting the flow of throttle valve.(4)The orthogonal test was carried out with the layer thickness,layer depth,rubber roller gap and rubber roller speed as experimental factors,the leakage rate of Camellia fruit and the damage rate of flower bud as experimental indexes.The test results showed that:compared with the picking device without layer mechanism,the average damage rate of flower bud of layer picking device was reduced by 6.22%.By comprehensive scoring method,the optimum picked parameters for Ganwu No.1Camellia were obtained:layer thickness 360 mm,layer depth 290 mm,rubber roller gap18 mm,rubber roller speed 65r/min.Under this working condition,the leakage rate of Camellia fruit is 13.33%,and the damage rate of flower bud is 6.33%.