| This paper was based on an environment of Fresh food E-commerce.Apples,which belong to one of the fresh products had been chosen as the research object.And at the meanwhile,a common packaging buffer cushion had been used with different specifications.In order to comply with the sale mode of Fresh food E-commerce in the future,mechanization and collection of shipment will be the development tendency,vibration condition therefore has the potential to significantly reduce the value of the apples during transportation.A research on vibration damage characteristics was carried out on transport packaging composed of apples and buffer cushion.This paper was based on the prior research of vibration damage characteristics,to evolve a rule to establish vibration proof packaging database of fruits,and to put forward a proposal to develop the vibration proof packaging CAD system of fruits.The main contents of this study are as follows:(1)Established the basic idea and design thought of fruit vibration proof packaging system.And then the research on vibration damage of Apples is based on the design thought,to make research method and target coordinate with each other.(2)In the study of Apple's resonance damage,stress values of apples was taken as the standard to judge whether the apple tissue was damaged.Compressive tests was also carried out to determine the critical stress value when the apple tissue was damaged.It turned out that the critical stress value is approximately equal to stiffness of apples(The diameter of the probe tip is 8mm,and with a compression speed of 25mm/min).Therefore,Apple's hardness value can be used to judge that whether the apple tissue is damaged.lt is also found that the biological yield load value on the bottom part is higher than the side part.(3)The thickness and density of the buffer cushions are respectively 3mm?5mm?10mm and 18kg/m~3?25kg/m~3?32kg/m~3,Compression test which aimed to obtain S-?X curves(S:theoretical contact area,?X:relative deformation of material)and F-?X curves(F:Theoretical load,?X:relative deformation of material)was carried out with universal material machine?graph paper and inkpad.According to the processed data,the fitting equations were obtained with a goodness-of-fit of 95%.The stress value of the apple in the process of vibration is obtained by S-?X curves and F-?X curves,and then compared with critical stress values of apples to determine whether it is damaged because of resonance.lt is worth mentioning that Halcon software were used to process the data during the test,the pixel values in special regions were extracted toachieve the contact area of apples and materials.(4)Sine sweep vibration test of transport packaging for apples in different ranges of quality,diameter,hardness were carried out with different specifications of EPE cushion.A series of curves oftransmissibility were obtained,and a method of creating the database of products and materials were provided as while.(5)Resonance check combined with critical stress value of applesn S-?X curves?F-AX curves?curves of transmissibility and load spectrum which is a representation of transport conditions;and vibration fatigue check used the results of vibration fatigue test.Finally,a CAD software was designed by MATLAB/GUI. |
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