Discrimination of Internal Quality of Agricultural Products Using Response Properties for Vibration (Part 1)

Relationship between Quality of Watermelon and Vibrational Frequency

Abstract

An easy nondestructive discrimination method for detecting internal quality of watermelon, especially internal crack and maturity was proposed using FFT analyzing techniques.
At first, the relationships between transmitted frequency, velocity and mass and internal quality of watermelons were theoretically analyzed assuming a homogeneous elastic sphere model. Moreover, a simple hitting apparatus was developed to measure the properties of these vibrations and sounds for analyzing the theoretically obtained results. The discrimination of the internal crack and maturity of these watermelons could be carried out using the index obtained from these analyzing techniques. The internal crack ratio can also be described by dividing the difference of the maximum and the second amplitudes in the spectrum by the maximum amplitude.