1. Damage Detection in Eggshell Using Lamb Waves

The application of Lamb waves is gaining attention in the scientific community for diagnosing defects in the thin-walled structures. The lamb waves have also been extensively employed in the aerospace, civil, and mechanical industries for detection of damage especially in the thin-walled plate or cylindrical structures. In the same direction, we have explored the application of Lamb waves in crack detection of chicken’s egg. Eggshell is primarily composed of calcium carbonate (CaCO₃) stabilized by a protein matrix. This protein matrix provides mechanical strength to the CaCO₃ layer. The eggshell damage while laying and transportation is a major problem faced by the poultry industry. Eggshell damage also results in major economic loss as the cracked eggs must be discarded while sorting and selling. The cracked eggshells have been identified manually which is a laborious and time-consuming process. Thus, for rapid and efficient detection of eggshell cracks various digital imaging-based algorithms, X-ray and gamma, optical transmission, nuclear magnetic resonance (NMR) and electrical properties-based techniques have been developed. However, the application of Lamb waves for the detection of eggshell crack has not been explored till now. This is the first study that reports the application of Lamb waves for detecting cracks in the eggshell. This technique is economical compared to other available techniques. We have carried out finite element (FE) modelling and simulations on the chicken eggshells. In order to capture the wave passing through the shell, we have calculated the minimum element size requirement for a given FE mesh and the time increments required to capture the wave in the shell. The simulation results show the accurate detection of eggshell cracks. This technique has a great potential to be employed at an industrial scale for sorting of the cracked and intact eggs.