Vibration Characteristic Analysis Of Good Eggs And Cracked Eggs

As the protective film to prevent egg contents from being damaged, the intact of egg shell has an significant importance on egg’s conservation and package. Therefore, the detection of egg shell’s dilapidation also is very important. Traditional detection method is artificial detection which is done through eyes to see or ears to hear. But this kind of method is of low work efficiency and poor accuracy. In recent years, many scholars have got some achievements with the aid of vibration theory through studying some farm products’ vibration property to test their quality, such as pears, peaches, leeches, grapes and so on. O n the basis of summarizing predecessors’ idea, this paper uses the method of applying mechanical shock on egg shell to confirm the impact factor on egg shell’s vibration characteristic. Thus, it can offer another thought for the detection of egg shells’ dilapidation.(1)To establish the data acquisition systemThe data acquisition system is made up of acceleration sensor produced in America with the type of PC B356A16 and dynamic signal analysis instrument coco-80 containing a data acquisition card and a charge amplifier provided by the Crystal Instruments. It can collect vibration data quickly and accurately.(2)To study the spectrum characteristics of non-dilapidation eggs Acquiring non-dilapidation egg samples with different weight and shell intensity, tapping experiment is carried out in the data acquisition system under the condition of different tapping material, part and position. After acquiring the experiment data, fast fourier transform is carried out on the data and get the frequency response curve. Then, extract the main response frequency. After analyzing the results, it shows that egg’s weight has a significant influence on the main response frequency. As to the non-dilapidation eggs with similar shell intensity, the main response frequency of eggs with large mass is less. On the contrary, the main response frequency of eggs with small mass is larger. And, there is a good negative correlation between them which is 0.9441. The main response frequency increases with the shell intensity increasing, and there is a good correlation between them which is 0.9332. There is little change in the main response frequency o n the condition of different tapping material, position and simulation part. The spectrogram of non-dilapidation eggs shows a regularity, and it has an obvious resonance peak.(3) To study of Spectral characteristics on good eggs and crack eggs First. get a number of good shell eggs and crack eggs, then repeat the vibration test of(2).The result shows that:1, there are several large frequency with approximate amplitude and high density on response characteristics curve of crack eggs, but don’t have significant main frequency. 2.The response frequency of crack eggs is significantly higher than the main frequency of good shell eggs, and the value is great generally. 3.The main frequency of different measuring points of crack eggs have large differences.(4)To establish the main frequency response prediction model The research shows that the main characteristic parameters to distinguish the good shell eggs and the crack eggs is the response dominant frequency. Meanwhile the research analyzes the physical parameters which impact the response main frequency, and found that the shell thickness and egg shaped index has less effect on the response to the main frequency, therefore, in prediction model of response main frequency, excluding the shell thickness, egg-shaped index, to determine the prediction model of response main frequency,and analyses the significance of regression equation and physical parameters to the response main frequency.Results show that tapping method can predict the change of main frequency response, strength of eggshell and quality of egg have good correlation with response main frequency. With the increase of eggshell strength, the response main frequency increased gradually; with the increase of quality of eggs, the response main frequenc y is reduced, But the always main frequency always in a predictable range, this means that testing response main frequency of eggs by nondestructive testing technology have theoretical basis, it’s completely feasible. Response main frequency of good shell egg and crack eggs in different main frequency range also means that, using the method of tapping to discriminate good shell eggs and crack eggs is completely feasible.