| As a vegetable with great local characteristics,black leaf-drooped vegetable is entering people’s lives with a thriving trend.In recent years,due to the strong support of the black leaf-drooped vegetable planting industry in Rugao,Jiangsu Province,the number of large-scale black leaf-drooped vegetable planting bases in the area has steadily increased,and the brand effect has also formed.However,the development of the black leaf-drooped vegetable planting industry is restricted by the limited level of harvesting mechanization.At present,many companies and universities have made gratifying progress in the research and creation of leafy vegetable harvesters.However,these harvesting machines generally have the disadvantages of poor adaptability and are not suitable for the unique black leaf-drooped vegetable.In order to fill the gap of harvester of black leaf-drooped vegetable and improve the level of harvesting of black leaf-drooped vegetable in Rugao,it is urgent to design a vegetable harvesting machine that has strong adaptability and pertinence for black leaf-drooped vegetable in Rugao.In this paper,considering the unique growth characteristics of black leaf-drooped vegetable,combined with its growth environment,a small electric crawler harvester of black leaf-drooped vegetable is designed.The harvester integrates the cutting,conveying and collecting functions of black leaf-drooped vegetable.And it has far-reaching significance for improving the efficiency of vegetable harvesting,reducing the labor intensity of farmers,and promoting the development of the regional vegetable planting industry.The specific research contents are as follows:1.Test and analysis of mechanical properties of the rhizomes of black leaf-drooped vegetable.The parameters of compression strength,shear strength and elastic modulus of the rhizomes were obtained by the mechanical characteristic test,which laid the foundation for the subsequent design calculation of the cutting device and the setting of the finite element analysis parameters.2.The design of the overall scheme of the small electric crawler harvester of black leaf-drooped vegetable.Taking the special growth characteristics of black leaf-drooped vegetable into account,the harvester was required to cut into the soil,to poke the leaves,and to function reliably.According to the specific design requirements,the overall structure of the small electric crawler harvester included the following devices:crawler chassis walking device,cutting device,conveying device,stubble height adjustment device and so on.3.The design and power demand analysis of the key components of the small electric crawler harvester of black leaf-drooped vegetable.According to the overall design plan of the harvester,the structure design and selection of the crawler chassis walking device,cutting device,conveying device and stubble height adjustment device of the harvester were carried out.Calculated the theoretical power required by the above device according to the requirements,and selected the appropriate motor model.4.Finite element analysis of the frame and cutting process of the small electric crawler harvester of black leaf-drooped vegetable.Through adopting the finite element analysis software ANSYS-Workbench,the corresponding structural statics analysis of the frame was carried out,and the deformation and stress cloud diagram after loading was obtained.The simulation results showed that the deformation and stress of the material were in its allowable use during the working process of the frame.The vibration modal analysis of the frame was carried out,and the 6th order vibration shape of the frame was obtained.The output frequency of the motor was compared with the 6th order vibration shape.It could be seen that the frame would not suffer from resonance phenomenon during the working process of the harvester.Through the explicit dynamics analysis,the condition that the disc cutter cutting the rhizomes of the black leaf-drooped vegetable under the soil at different speeds was simulated,and the most suitable speed of the cutter was obtained from the simulation results,which could ideally realize the cutting of the rhizomes.5.Prototype manufacturing and test of the small electric crawler harvester of black leaf-drooped vegetable.Together with Taizhou Xiechuang Agricultural Equipment Co.,Ltd.to complete the prototype manufacturing,then designed and carried out field trials that met the specifications,and comprehensively evaluated the test results of the harvester from the aspects of harvesting efficiency,missed cutting rate,and power consumption.The test results showed that the harvesting efficiency of the harvester was about0.1 hm2·h-1,the missed cutting rate was less than 5%,and the power consumption was about28.77 k W·h/hm2.The test indicators met the expected requirements.The small electric crawler harvester of black leaf-drooped vegetable designed in this paper could realize the cutting,conveying and collecting operations of black leaf-drooped vegetable,and effectively solved the problems in the harvesting process.At the same time,it could liberate manpower to a greater extent,improve farmers’sense of happiness and quality of work,and shorten the time of work;also,the harvester used green power battery as the power source,which conformed to the concept of environmental protection. |
