Dual Resonant Frequencies Effects on an Induction-Based Oil Palm Fruit Sensor

Sensors

Noor Hasmiza Harun²  Norhisam Misron²  Roslina Mohd Sidek²  Ishak Aris²  Hiroyuki Wakiwaka¹ 

[1] Faculty of Engineering, Shinshu University, Wakasato 4-17-1, Nagano 380-8553, Japan; E-Mails:;Faculty of Engineering, University Putra Malaysia, Serdang 43400, Selangor, Malaysia; E-Mails:

关键词: induction;    resonant frequency;    air coil;    oil palm;    frequency characteristics;    maturity classification;    inductive concepts;   

DOI  :  10.3390/s141121923

来源: mdpi

【 摘 要 】

As the main exporter in the oil palm industry, the need to improve the quality of palm oil has become the main interest among all the palm oil millers in Malaysia. To produce good quality palm oil, it is important for the miller to harvest a good oil palm Fresh Fruit Bunch (FFB). Conventionally, the main reference used by Malaysian harvesters is the manual grading standard published by the Malaysian Palm Oil Board (MPOB). A good oil palm FFB consists of all matured fruitlets, aged between 18 to 21 weeks of antheses (WAA). To expedite the harvesting process, it is crucial to implement an automated detection system for determining the maturity of the oil palm FFB. Various automated detection methods have been proposed by researchers in the field to replace the conventional method. In our preliminary study, a novel oil palm fruit sensor to detect the maturity of oil palm fruit bunch was proposed. The design of the proposed air coil sensor based on the inductive sensor was further investigated mainly in the context of the effect of coil diameter to improve its sensitivity. In this paper, the sensitivity of the inductive sensor was further examined with a dual flat-type shape of air coil. The dual air coils were tested on fifteen samples of fruitlet from two categories, namely ripe and unripe. Samples were tested within 20 Hz to 10 MHz while evaluations on both peaks were done separately before the gap between peaks was analyzed. A comparative analysis was conducted to investigate the improvement in sensitivity of the induction-based oil palm fruit sensor as compared to previous works. Results from the comparative study proved that the inductive sensor using a dual flat-type shape air coil has improved by up to 167%. This provides an indication in the improvement in the coil sensitivity of the palm oil fruit sensor based on the induction concept.

【 授权许可】

CC BY   
© 2014 by the authors; licensee MDPI, Basel, Switzerland.