Research On Header Profile System Of Orderly Harvester For Leafy Vegetables

Leafy vegetables are widely planted in China,but the level of mechanization in the production process is low,and the labor intensity in the harvesting process accounts for nearly half of the total work intensity.Traditional leafy vegetable harvesting operations rely solely on labor,which time-consuming,laborious,and increased production costs.Therefore,the development of leafy vegetable harvesting equipment is in line with the trend of large-scale vegetable production.The existing leafy vegetable harvesting equipment has problems such as poor collection,and the improper cutting position of the cutting knife during the harvesting process leads to high leafy vegetable cutting residuals and even damage to the machinery.The harvest quality and efficiency of the leafy vegetable harvesting process are directly related.It affects the appearance of harvested leafy vegetables and the interests of producers.Therefore,the development of intelligent equipment for low-loss and orderly harvesting of leafy vegetables is of great significance to improve the quality of leafy vegetables harvest and reduce production labor intensity.Aiming at the above-mentioned problems,this paper studies the cutting table profiling system of an orderly harvesting equipment for leafy vegetables.The main research contents are as follows:(1)By studying the geometric characteristics and spatial distribution of leafy vegetables during the harvest period,as well as the ridge height and ridge surface fluctuation changes,the profiling detection device of the header profiling system,the header executive device and the electrical control system were demonstrated,and the leafy vegetables were finally determined.The cutting head profiling system of the orderly harvester adopts the left and right sets of front profiling detection,the head profiling adjustment and lifting hydraulic system based on the ridge surface,and the general layout and working principle of the corresponding electrical control system.(2)According to the demand analysis of the profiling system of the header,the main structure and key dimensions of the profiling detection mechanism are designed,and the detection results are calibrated;through theoretical analysis,the main factors affecting the detection performance of the profiling detection mechanism are obtained,and according to The initial angle,spring preload,spring stiffness coefficient,and operating speed are selected as the main influencing factors of the profiling detection performance;the single factor test is used to determine the response surface test level of each parameter,and the detection performance of the profiling detection mechanism is determined by the response surface method.Perform bench test,analyze and finally determine that the optimal parameters of the profiling detection mechanism are the initial angle of 55°,the spring preload of 5N,the spring stiffness coefficient of 0.477N/mm,and the operating speed of 0.16m/s.At this time,the normal ridge surface subsidence amount The average value is 2.4mm,the amount of depression on the convex ridge surface is 5.2mm,and the amount of depression on the concave ridge surface is 0.6mm.(3)According to the requirements of harvester’s header lifting and profiling adjustment,the plan was demonstrated and selected,and the pure hydraulic adjustment method was finally selected;the header elevating and profiling adjustment mechanism and the schematic diagram of the hydraulic system were designed,and the execution cylinders and headers/cutters were calculated.The geometric change relationship between the heights and the parameters of each cylinder are determined;the ADAMS software is used to simulate and analyze the lifting and profiling adjustment system of the header,and it is verified that the relevant parameters of the designed execution cylinder can meet the requirements of the lifting and profiling adjustment.According to this,the relevant parameters of the hydraulic system are designed;the relevant hardware of the designed hydraulic system is selected,and the hydraulic system is assembled and debugged.(4)Carry out the hardware equipment configuration of the header profiling control system and the specific configuration of related expansion modules and the writing of software programs.The hardware part mainly includes the CPU module and the corresponding expansion module,the specific hardware parameter configuration,and the sensor selection;the software part mainly completes the profiling detection information processing,the cylinder position signal acquisition,the profiling adjustment calculation and response processing,and the profiling adjustment execution The design of submodule programs;the logic and function of the designed program are verified by the simulator and the program is modified according to the simulation results.(5)Prototype trial production and flat ground and field test,through the virtual prototype design and verify the feasibility of the system structure,prototype trial production;through the header profiling system flat ground test,the header profiling execution cylinder motion parameters and system response time were tested,and the test results showed The motion parameters of the header profiling execution cylinder are relatively stable under different ridge height environments;the average stubble height,the coefficient of variation of the stubble height,the profiling control accuracy of the header,and the number of times the cutter touches the soil are used as the evaluation indicators for the field test.,The absolute error between the average stubble height and the preset stubble height is less than 2mm,the average profiling control accuracy is 91%,the average number of soil touches is 2,and the average coefficient of variation of the stubble height is 22.35%,indicating that the design in this paper The header profiling system has a good control effect.