Research And Design Of Lightweight Leafy Vegetable Harveste

At present,the mechanization of leafy vegetables harvesting process in China has been improved,but the adaptability of harvesting process is poor in different leafy vegetables planting areas,especially in small areas,and it is impossible to achieve the characteristics of both lightweight and harvesting performance.Therefore,it is of great significance to strengthen the research and design of leafy vegetable harvesting machinery to improve the production level of leafy vegetables.Under this background,this paper has completed the research and design of a lightweight leafy vegetable harvester.The final equipment needs to achieve a harvesting rate higher than 95%,a damage rate lower than 5%,and a lightweight design requirement.The main research contents are as follows:(1)According to the design requirements of leaf vegetable planting,a reasonable harvesting scheme is worked out.The principle analysis and structural design of the main frame,cutter equipment,scraper chain lifting conveyor,height adjustment device and other key components of the harvester are carried out.The three-dimensional modeling of each device is completed by SolidWorks software,and finally the virtual assembly of each component is carried out in the software to obtain the three-dimensional model of the whole machine.(2)Through the analysis of working conditions,it is concluded that the influencing factors of cutting performance are blade parameters and cutting speed ratio,and its parameter design is obtained by using the functional relationship between cutting state and blade parameters.Combined with the movement state and cutting diagram of leafy vegetables under different cutting speed ratios,the optimal cutting speed ratio interval is determined to be 1.15-1.25.Then Adams software is used to simulate the kinematics of the cutting device.By analyzing the curves of speed and displacement,the correctness of the selection of cutter motor and driving motor is reflected,and the rationality of the design of the cutting device is verified.(3)The statics and modal analysis of the main frame,driving shaft,cutting device and other key components of the harvester are completed in ANSYS.The calculated equivalent stress nephogram,equivalent deformation nephogram,and 1-6 modal shapes are analyzed to verify the stiffness,strength and natural frequency safety of key components.Topology optimization is carried out on the cutting device which is prone to stress concentration and resonance damage,so as to reduce the weight and stress of the cutting knife.Finally,the rationality of the strength and stiffness of the equipment is verified by the statics analysis of the whole machine.(4)Complete the processing and assembly of the harvester and select the performance index,and then carry out the test in the vegetable field.By using SPSS software,the curve estimation of the advancing speed,picking rate and damage rate of the equipment was obtained.By analyzing the solved curve,the optimal advancing speed of the leafy vegetable harvester was finally determined to be 0.5m/s,at which time the picking rate and damage rate both met the design requirements.