Design And Simulation Of Automatic Grading Equipment For Asparagus

Green asparagus is an edible species of the genus Asparagus in the lily family.With its tender young stems as an ingredient,it is a low-calorie,nutritious,medicinal and high-grade vegetable that has become popular with consumers in recent years.China ranks first in the world in terms of asparagus production and cultivation area.The size(maximum diameter at the base)of the harvested asparagus varies and its sales value is greatly affected by it.In order to increase the sales price of asparagus,grading is essential,but the current grading method(manual)has disadvantages such as high labour costs,low automation,low efficiency,damage and poor precision.Furthermore,the long,thin,irregular and soft shape of asparagus makes it difficult to determine the maximum size and damage during grading.Therefore,it is important for the asparagus industry to design a high performance automatic asparagus grading equipment to address the shortcomings of manual grading and the difficulties in the grading process.Firstly,according to the requirements put forward by the enterprise and the difficulties in the process of asparagus grading,the demand analysis of the asparagus automatic grading equipment was carried out using the exhaustive grasping key method,then the functional analysis method was applied to the scheme design of its main mechanisms,after which the hierarchical analysis method was used to evaluate the decision to determine the final structural design scheme,and finally the design parameters were determined in conjunction with the enterprise and the overall layout.The modeling software solid works is used to design the structure and determine the key parameters of the main components of the asparagus automatic grading equipment,as well as the selection and calculation of some standard parts and the layout of the whole machine.Secondly,the machine vision inspection section was designed for problems such as difficulty in determining the location of the maximum size of the asparagus base.In the asparagus image acquisition module,a detailed design selection of image acquisition hardware including cameras,lenses and light sources was made,and in the asparagus image processing module,a comparative study of typical methods in each of its processes(pre-processing,image segmentation,contour extraction and size detection)was carried out,and in the size detection the measurement of the maximum diameter of the asparagus base based on the outer wrapping rectangle method was proposed,and from 10 asparagus The experimental results of the inspection showed that the maximum detection error was 0.5mm(less than 2mm,within the specified error range)and the grading was correct up to 100%.A design analysis was then carried out on the entire control section of the equipment,including control flow analysis,I/O allocation,hardware wiring and ladder programs.Finally,the asparagus automatic grading equipment was simulated and verified by using Adams software.The results show that:the force and velocity changes of asparagus in each stage of grading process are within reasonable range;the predetermined movements and functions can be realized.A virtual prototype of asparagus automatic grading equipment was finally obtained,while the simulation verified the feasibility and rationality of its design,which provided support for the development of the whole machine in the future,and also provided reference for the size detection of other irregular plants.