Low-Cost Capacitive Humidity Sensor for Application Within Flexible RFID Labels Based on Microcontroller Systems

Author

Pelegrí-Sebastiá, José ; García-Breijo, Eduardo ; Ibanez, J. ; Sogorb, Tomas ; Laguarda-Miro, Nicolís ; Garrigues, Josí

Author_Institution

Inst. de Investig. para la Gestion Integrada de Zonas Costeras, Univ. Politec. de Valencia, Grao de Gandia, Spain

Volume

61

Issue

2

fYear

2012

Firstpage

545

Lastpage

553

Abstract

This paper reports on the fabrication of a capacitive-type relative humidity (RH) sensor using screen printing processes for electrode film deposition. The applied measurement method based on microcontrollers is also reported. In this specific case, the microcontroller is used to measure RH by means of a capacitive sensor with a simple low-cost electronic system. In addition, a comparison between two different types of polyester substrates [Melinex (DuPont) and CG3460 (3M)] is shown. Both polyester substrates have similar properties, and only the thickness is different (175 μm for Melinex and 100 μm for CG3460). A nonlineal response has been obtained in this type of sensors. In order to linearize the response and reduce the external hardware, an artificial neural network embedded into the microcontroller has been used.

Keywords

capacitive sensors; computerised instrumentation; electrodeposits; humidity sensors; microcontrollers; neural nets; radiofrequency identification; RH sensor; artificial neural network; electrode film deposition; external hardware; flexible RFID label; low-cost capacitive humidity sensor; low-cost electronic system; microcontroller; polyester substrates; screen printing processes; size 100 mum; size 175 mum; Capacitance; Humidity; Ink; Microcontrollers; Printing; Radiofrequency identification; Substrates; Artificial neural network (ANN); capacitive-type sensor; humidity sensor; microcontroller; radio frequency identification (RFID) label; screen printing;

fLanguage

English

Journal_Title

Instrumentation and Measurement, IEEE Transactions on

Publisher

ieee

ISSN

0018-9456

Type

jour

DOI

10.1109/TIM.2011.2164860

Filename

6032101