Firmness evaluation of melon using its vibration characteristic and finite element analysis

Abstract

Abstract:The "Huang gua" melons were measured for their physical properties including firmness and static elastic modulus. The vibrational characteristics of fruits and vegetables are governed by their elastic modulus (firmness), mass, and geometry. Therefore, it is possible to evaluate firmness of fruits and vegetables based on their vibrational characteristics. Analysis of the vibration responses of a fruit is suggested for measuring elastic properties (Firmness) non-destructively. The impulse response method is often used to measure firmness of fruits. The fruit was excited using three types of balls (wooden, steel and rubber) and the vibration is detected by an accelerometer. The Instron device was used to measure the static elastic modulus of the inner, middle and outer portions of melon flesh. Finite element (FE) technique was used to determine the optimum excitation location of the chosen measurement sensor and to analyze the mode shape fruits. Four types of mode shapes (torsional or flexural mode shape, first-type, second-type spherical mode and breathing mode shape) were found. Finite element simulation results agreed well with experimental results. Correlation between the firmness and resonant frequency (r 2 =0.91) and between the resonant frequency and stiffness factor (r 2 =0.74) existed. The optimum location and suitable direction for excitation and response measurement on the fruit were suggested.

Qualitative and Quantitative Evaluation of Pomelo Maturity Using Multivariate Combination of Chemical and Physical Properties

“…This was probably due to small variations in the pomelo size. The result agreed partially with reports that the square of the second resonant frequency was linearly associated with Young's modulus of apple (Lu and Abbott 1997) and the firmness showed high correlation ( R 2 = 0.91) with the resonant frequency of the melon (Nourain et al. 2005).…”

“…Many studies report successful techniques that can be used to evaluate firmness (Chen et al. 1985, 1996; Chen and De Baerdemaeker 1993; Shmulevich 1998; Nourain et al. 2005; Diezma‐Iglesias et al.…”

Internal bruising prediction in watermelon compression using nonlinear models

“…They noted that the simulated patterns of failure closely agree with those observed after compressive loading on fruits. Also, several studies have appeared in the scientific literature on modal analysis of fruits using the finite element method (Chen et al, 1996;Jancsok et al, 2001;Nourain et al, 2005).…”

The relation between the texture properties of mangosteen (Garcinia<br>mangostana Linn.) and the resonance frequency in detection of the<br>translucent and yellow gummy latex

“…These authors impacted each fruit near the stem and read the frequency at the opposite side using an accelerometer. Moreover, the nondestructive vibration used to determine the maturity levels of durian (Kongrattanaprasert et al, 2001), the acoustic measurement and an intrusive method for determining tissue firmness were compared to assess the textural properties of kiwifruit (Muramatsu et al, 1997), firmness measurement of muskmelons by acoustic impulse transmission (Junichi et al, 2005), the vibration element analysis to determine firmness evaluation of melon (Nourain et al, 2005). In addition, the Laser Doppler Vibrometer (LDV) technique was monitor ripening behavior temperature (Shoji et al, 2006), the acoustic impulses were detected internal hollow in watermelon (Diezma et al, 2002), the acoustic response evaluation of the storability of Piel de Sapo melons (Lleó et al, 2005).…”