Design and Fabrication of a Watermelon Ripeness Tester Using Matlab Software GUI

A non-destructive way to determine the ripeness of watermelon is very difficult, by outward characteristics such as size or external colour and used methods include different limitations. In this study a simple and intelligent method to determine the ripeness of watermelon was designed and developed by integrating a conventional method with electronics device, the ripeness of watermelon can be determined easily and reliable. Microphone was placed under the fruit sample to record a thumping signal. The recorded signals were converted into Fast Fourier Transform (FFT) waveform using MATLAB Software. The patterns of FFT waveforms were analysed using average magnitude at the frequency between 100 Hz and 4000 Hz to classify the ripeness. The average magnitude of was within the range of 0.00019 to 0.00030, and the magnitudes below 0.00025 were termed unripe and magnitudes above 0.00025 were termed ripe. Recommendations for further studies were stated.