• Journal of Biosystems Engineering
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• v.23 no.1
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• pp.67-74
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• 1998

A nondestructive quality inspection technique using acoustic impulse response method was developed for eggshell inspection. An experimental system was built to generate the impact force, to measure the response signal and to analyze the frequency spectrum. This system includes an impulse generating unit, an egg holding seal a microphone with preamplifier, and a DSP board installed on Personal Computer. A simple algorithm .was developed for crack detection. Using the developed system with algorithm, crack detection ability was evaluated and the error rate to estimate the normal egg as cracked was found to be 4% and the error rate to estimate the cracked egg as normal was also found to be 4%. This system could be adopted in industry with some modification.

• Current Research on Agriculture and Life Sciences
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• v.32 no.4
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• pp.231-235
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• 2014

This study performed a benefit cost analysis of an automatic eggshell crack detection system. Based on various cost benefit analysis methods, including the net present value (NPV), internal rate of return (IRR), and benefit cost ratio (B/C Ratio), the automatic eggshell crack detection system was confirmed to have economic validity. The NPVs were 175,035,645 won at a 5% discount rate and 129,082,393 won at a 10% discount rate. Plus, the IRRs were 0.686 at a 5% discount rate and 0.660 at a 10% discount rate. Finally, the B/C ratios were 1.981 at a 5% discount rate and 1.900 at a 10% discount rate.

• Journal of Biosystems Engineering
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• v.33 no.5
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• pp.348-354
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• 2008

Egg grading is determined by exterior and interior quality. Among the evaluation methods for the egg quality, a candling method is common to identify eggs with cracked shells and interior defects. But this method is time-consuming and laborious. In addition, practically, it is challenging to detect hairline and micro cracks. In this study, an on-line inspection system based on acoustic resonance frequency analysis was developed to detect hairline cracks on eggshells. A roller conveyor was used to transfer eggs along one lane to the impact position where each of eggs rotated by the roller was excited with an impact device at four different locations on the eggshell equator. The impact device was consisted of a plastic hammer and a rotary solenoid. The acoustic response of the egg to the impact was measured with a small condenser microphone at the same position as the impact device was installed. Two acoustic parameters, correlation coefficient for normalized power spectra and standard deviation of peak resonant frequencies, were used to detect cracked eggs. Intact eggs showed relatively high correlations among the four normalized power spectra and low standard deviations of the four peak resonant frequencies. On the other hand, cracked eggs showed low correlations and high standard deviations as compared to the intact. This method allowed a crack detection rate of 97.6%.