Design And Development Of Automatic Fruit Sorting System

China is a large country of fruit planting and output area,but there are problems of low sorting capacity of fruit grade,most of which are manual sorting,high cost and low efficiency.The traditional sorting equipment is based on the physical characteristics of fruit,which can not detect the content of internal substances of fruit.Therefore,the development of fruit sorting equipment based on the detection of the substance content is great significance.I take millennium fruit as an example in this paper,A kind of automatic fruit sorting equipment is designed.At the same time,the equipment can be changed and upgraded for other fruit.This paper mainly designs and develops the sorting equipment from the following aspects:(1)The whole mechanical structure design of sorting equipment is put forward,which mainly includes synchronous belt conveyor,modular tray mechanism and loading device.Considering that the transport device needs assist the loading device,unloading device and spectrum detection,the transmission scheme of synchronous belt drive combined with tray mechanism is proposed under the analysis of the existing transmission mode.Design and select the synchronous belt,determine the size parameters of synchronous belt and synchromesh gear.Collect the size of 60 millennium fruits,and design the tray mechanism,loading device and unloading mode.(2)Based on the comparison and analysis of the existing control schemes,a servo control system is proposed to realize the control process,including the hardware design and the upper computer software design.The hardware part includes industrial computer,PCI motion control,terminal board module IO distribution,servo driver and servo motor selection.The software includes interface design,motion logic control design and unloading control design.The predicted value of sugar and acidity content is taken as the grade data,the coding position of the sorting motor is calculated by combining with the initial coding position of the spectral detection motor,finally the air solenoid valve is controlled to carry out the compressed gas.(3)A mathematical model for predicting the degree of sugar and acidity content in millennium fruit was established by using NIRS spectroscopy and partial least square regression analysis.In this paper,NIRS spectroscopy(wavelength:605.95-1102.6nm)is used to collect the absorbance values of millennial fruit at each wavelength through transmission,andSG convolution smoothing filter and SNV variable standardization correction are carried out successively.Partial least square regression cross validation method is used to establish the prediction mathematical model of sugar and acidity content,the external prediction test is carried out and get a good prediction results.Through the design of mechanical mechanism and control system and the establishment of mathematical model for prediction of sugar and acidity content,the assembly of the whole prototype is completed.the relevant parameters are set and optimized in combination with relevant experiments.