Open Access
Micro-displacement sensor based on hollow core fiber interferometers
(Optica, 2022) Sánchez González, Arturo; Rodríguez Rodríguez, Armando; Dauliat, Romain; Jamier, Raphael; Roy, Philippe; Pérez Herrera, Rosa Ana; López-Amo Sáinz, Manuel; Ingeniería Eléctrica, Electrónica y de Comunicación; Institute of Smart Cities - ISC; Ingeniaritza Elektrikoa, Elektronikoaren eta Telekomunikazio Ingeniaritzaren
An interferometric sensor based on hollow core fibers for the measurement of micro-displacement has been designed. Its characterization has resulted in a linear response, suggesting its application in pressure sensors.
Open Access
Optical fiber sensor for water velocity measurement in rivers and channels
(Nature Research, 2024) Rodríguez Rodríguez, Armando; Diéguez Elizondo, Pedro; Urroz Unzueta, José Carlos; Bravo Acha, Mikel; López Rodríguez, José Javier; López-Amo Sáinz, Manuel; Ingeniería; Ingeniaritza; Ingeniería Eléctrica, Electrónica y de Comunicación; Ingeniaritza Elektrikoa, Elektronikoa eta Telekomunikazio Ingeniaritza; Institute of Smart Cities - ISC
In this work, optical fiber Bragg grating sensors were used to measure water velocity and examine how it was distributed in open channels. Several types of coatings were incorporated into the design of the sensors to examine their effects on the strain that the fibers experienced as a result of the water flow. Due to their low elastic coefficient, which reduced the hysteresis, the results indicated that the aluminum- and acrylate-coated fibers had the best performance. ANSYS-CFX V2020 R2 software was used to model the strain encountered by the fibers under various flow rates to assess the performance of the FBG sensors. The calculations and actual data exhibited good convergence, demonstrating the accuracy of the FBG sensors in determining water velocity. The study illustrated the usability of the proposal in both scenarios by contrasting its application in rivers and channels.
Open Access
Aluminum coated fiber optic sensor for enhancing flow rate measurement
(SPIE, 2023) Rodríguez Rodríguez, Armando; Urroz Unzueta, José Carlos; Diéguez Elizondo, Pedro; Bravo Acha, Mikel; López-Amo Sáinz, Manuel; López Rodríguez, José Javier; Ingeniería; Ingeniería Eléctrica, Electrónica y de Comunicación; Institute of Smart Cities - ISC; Ingeniaritza; Ingeniaritza Elektrikoa, Elektronikoaren eta Telekomunikazio Ingeniaritzaren
A water flow and velocity aluminum-coated Fiber Bragg Grating sensor system for open channels was designed, simulated and tested. The sensing head was designed, ruggedized and customized to measure velocities at different depths, in order to calculate the discharge in open channels. This paper shows, for the first time to our knowledge, the simulation of such kind of fiber sensors in open channels.
Open Access
Development of a water flow and velocity optical fiber sensor for field testing
(Optica Publishing Group, 2022) Rodríguez Rodríguez, Armando; Urroz Unzueta, José Carlos; Diéguez Elizondo, Pedro; Bravo Acha, Mikel; López-Amo Sáinz, Manuel; López Rodríguez, José Javier; Ingeniería; Ingeniería Eléctrica, Electrónica y de Comunicación; Institute of Smart Cities - ISC; Ingeniaritza; Ingeniaritza Elektrikoa, Elektronikoaren eta Telekomunikazio Ingeniaritzaren
A water flow and velocity fiber optic sensor system was developed and tested. The sensing head was especially developed and ruggedized to measure velocities at different depths, in order to calculate the discharge in channels.
Open Access
Optical fiber pH sensors based on PAni-coated microstructured optical fibers
(IEEE, 2024-07-10) Rodríguez Rodríguez, Armando; Lopes, Guilherme; Nedoma, Jan; Pereira, Sónia O.; Fernandes, Antonio J. S.; Jamier, Raphael; Roy, Philippe; Bravo Acha, Mikel; López-Amo Sáinz, Manuel; Marques, Carlos; Ingeniería Eléctrica, Electrónica y de Comunicación; Ingeniaritza Elektrikoa, Elektronikoa eta Telekomunikazio Ingeniaritza; Institute of Smart Cities - ISC; Universidad Pública de Navarra / Nafarroako Unibertsitate Publikoa
In this article, we report the analysis of a novel optical fiber pH sensor based in polyaniline (PAni) coating applied on a trenched core-free (only-bridge) silica fiber. The results are compared to another pH sensor based on side-polished silica fiber. The pH-sensitive polymer is synthesized over the fiber sample by means of oxidative polymerization, keeping records of the time where the reaction occurs to improve the sensitivity. The response to pH is enhanced in the case of the trenched core-free bridge fiber due to the higher interaction of the evanescent field with the PAni film and, thus, the surrounding media. The sensitivity in the linear zone of operation is 1.1 mW/pH, and a total transmittance of 55% in the pH range is 4.2-8.1. The repeatability of both sensors was checked, showing a high capability to perform studies in liquid samples due to its temperature independence, good sensitivity, and long-term stability.
Open Access
Design of optical fiber Bragg grating-based sensors for flow measurement in pipes
(Taylor & Francis, 2023) Diéguez Elizondo, Pedro; Rodríguez Rodríguez, Armando; Urroz Unzueta, José Carlos; López Rodríguez, José Javier; López-Amo Sáinz, Manuel; Ingeniería; Ingeniería Eléctrica, Electrónica y de Comunicación; Institute of Smart Cities - ISC; Ingeniaritza; Ingeniaritza Elektrikoa, Elektronikoaren eta Telekomunikazio Ingeniaritzaren
In this work, optical Fiber Bragg grating (FBG) sensors were used to measure water flow in pipes. Several types of coatings were incorporated into the design of the sensors to examine their effects on the elastic strain that the fiber underwent as a result of the water flow. ANSYS-CFX V2020 R2 software was used to model the elastic strain encountered by the fiber under various flow rates in order to assess the performance of the FBG sensors. The calculations and experimental data exhibited good convergence, demonstrating the accuracy of the FBG sensors in determining water flow. These calculations and procedures can be extrapolated to any other fluid.
Open Access
Power over fiber system for heterogeneous sensors multiplexing
(IEEE, 2024-06-12) Rodríguez Rodríguez, Armando; Vanegas Tenezaca, Evelyn Dayanara; Vento Álvarez, José Raúl; López-Amo Sáinz, Manuel; Bravo Acha, Mikel; Ingeniería Eléctrica, Electrónica y de Comunicación; Ingeniaritza Elektrikoa, Elektronikoa eta Telekomunikazio Ingeniaritza; Institute of Smart Cities - ISC; Universidad Pública de Navarra / Nafarroako Uniertsitate Publikoa
This paper presents a Power-over-Fiber based remote electronic and optical fiber sensors multiplexing scheme. The system architecture consists of a 50-km linear cavity Raman-fiber laser that is used for interrogation of FBG optical fiber sensors. Simultaneously, electronic sensors information is modulated in amplitude while the optical sensors' data are encoded in the spectral information. In order to bias the electronic sensors, the residual power of the Raman pump laser is collected in an energy harvesting unit. This electric power is used for biasing an ATTiny85 control unit and two electro-optical modulators. A proof-of-concept is presented where a couple of optical fiber-Bragg-gratings sensors collect strain information that is self-compensated in temperature according to the digital data achieved from the electronic sensors. A 9.6 kbit/s data rate was achieved using Mach-Zehnder amplitude modulators and a maximum 35 ksample/s was retrieved using a high-speed C-band spectrometer and performing spectral analysis via a software developed in Python. Authors