sensors-logo

Journal Browser

Journal Browser

Advanced Sensors Using Smart Materials

A special issue of Sensors (ISSN 1424-8220). This special issue belongs to the section "Sensor Materials".

Deadline for manuscript submissions: 10 July 2024 | Viewed by 7471

Special Issue Editors

Department of Aerospace Engineering, Embry-Riddle Aeronautical University, Daytona Beach, FL, USA
Interests: flexible sensors; acoustics; wireless; embedded sensors; additive manufacturing

E-Mail Website
Guest Editor
Department of Mechanical Engineering, University of Wisconsin, Madison, WI, USA
Interests: piezoelectrics; SMA; self-healing materials; ultrasonics; sensor integration
Special Issues, Collections and Topics in MDPI journals

E-Mail Website
Guest Editor
Department of Mechanical Engineering, Virginia Tech, Blacksburg, VA, USA
Interests: acoustics; vibrations; piezoelectric materials; metamaterials; acoustic tweezers

Special Issue Information

Dear Colleagues,

Sensor technologies have rapidly advanced opening new doors to true digital transformation, connecting machines, products, and people through industrial internet of things and digital twin platforms. With an increased focus on new sensing technologies, the development of advanced sensors that possess unique or multifunctional properties using various attributes of intelligent materials is accelerating the pace of the hyper-connected industrial revolution.

The goal of this Special Issue is to highlight the state-of-the-art research on the development of advanced sensors that utilize smart materials, which are formed in various sizes and shapes for diverse engineering and scientific fields. We sincerely invite you to submit original unpublished work on the listed or related topics.

Topics of interest include, but are not limited to, the following:

  • Smart materials for sensing
  • Sensing principles and technologies
  • Sensors with additive manufacturing
  • Flexible and wearable sensors
  • Biomedical sensors
  • Embeddable sensors
  • Metamaterial sensors
  • Multifunctional sensors
  • Wireless and remote sensors
  • Theory and modelling of advanced sensors
  • Design, manufacturing, data analysis of advanced sensors
  • AI and machine learning related to advanced sensors

Dr. Daewon Kim
Dr. Nathan Salowitz
Dr. Zhenhua Tian
Guest Editors

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Sensors is an international peer-reviewed open access semimonthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2600 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  • smart materials
  • sensing principles and technologies
  • sensors with additive manufacturing
  • flexible and wearable sensors
  • biomedical sensors
  • embeddable sensors
  • metamaterial sensors
  • multifunctional sensors
  • wireless and remote sensors
  • theory and modelling of advanced sensors
  • design, manufacturing, data analysis of advanced sensors
  • AI and machine learning related to advanced sensors

Published Papers (7 papers)

Order results
Result details
Select all
Export citation of selected articles as:

Research

15 pages, 3624 KiB  
Article
Polymer Nanocomposite Sensors with Improved Piezoelectric Properties through Additive Manufacturing
by Rishikesh Srinivasaraghavan Govindarajan, Zefu Ren, Isabel Melendez, Sandra K. S. Boetcher, Foram Madiyar and Daewon Kim
Sensors 2024, 24(9), 2694; https://doi.org/10.3390/s24092694 - 24 Apr 2024
Viewed by 271
Abstract
Additive manufacturing (AM) technology has recently seen increased utilization due to its versatility in using functional materials, offering a new pathway for next-generation conformal electronics in the smart sensor field. However, the limited availability of polymer-based ultraviolet (UV)-curable materials with enhanced piezoelectric properties [...] Read more.
Additive manufacturing (AM) technology has recently seen increased utilization due to its versatility in using functional materials, offering a new pathway for next-generation conformal electronics in the smart sensor field. However, the limited availability of polymer-based ultraviolet (UV)-curable materials with enhanced piezoelectric properties necessitates the development of a tailorable process suitable for 3D printing. This paper investigates the structural, thermal, rheological, mechanical, and piezoelectric properties of a newly developed sensor resin material. The polymer resin is based on polyvinylidene fluoride (PVDF) as a matrix, mixed with constituents enabling UV curability, and boron nitride nanotubes (BNNTs) are added to form a nanocomposite resin. The results demonstrate the successful micro-scale printability of the developed polymer and nanocomposite resins using a liquid crystal display (LCD)-based 3D printer. Additionally, incorporating BNNTs into the polymer matrix enhanced the piezoelectric properties, with an increase in the voltage response by up to 50.13%. This work provides new insights for the development of 3D printable flexible sensor devices and energy harvesting systems. Full article
(This article belongs to the Special Issue Advanced Sensors Using Smart Materials)
Show Figures

Figure 1

15 pages, 4908 KiB  
Article
Electromechanical Properties of Smart Vitrimers Reinforced with Carbon Nanotubes for SHM Applications
by Javier Gómez-Sánchez, Xoan F. Sánchez-Romate, Francisco Javier Espadas, Silvia G. Prolongo and Alberto Jiménez-Suárez
Sensors 2024, 24(3), 806; https://doi.org/10.3390/s24030806 - 26 Jan 2024
Viewed by 917
Abstract
The Structural Health Monitoring (SHM) capabilities of a well-studied self-healing epoxy resin based on disulfide bonds, through the addition of carbon nanotubes (CNTs), are studied. Since these materials demonstrated, in recent works, a high dependency of the dynamic hardener content on the repair [...] Read more.
The Structural Health Monitoring (SHM) capabilities of a well-studied self-healing epoxy resin based on disulfide bonds, through the addition of carbon nanotubes (CNTs), are studied. Since these materials demonstrated, in recent works, a high dependency of the dynamic hardener content on the repair performance, this study aimed to analyze the effect of the vitrimeric chemistry on the electromechanical properties by studying different 2-aminophenyl disulfide (2-AFD) hardener and CNT contents. The electrical conductivity increases with both the CNT and AFD contents, in general. Moreover, an excess of AFD close to the stoichiometric ratio with a low CNT content improved the tensile strength by 45%, while higher AFD contents promoted its detriment by 41% due to a reduced crosslinking density. However, no significant difference in the mechanical properties was observed at a higher CNT content, regardless of the AFD ratio. The developed materials demonstrate a robust electromechanical response at quasi-static conditions. The sensitivity significantly increases at higher AFD ratios, from 0.69 to 2.22 for the 0.2 wt.%. CNT system, which is advantageous due to the enhanced repair performance of these vitrimeric materials with a higher hardener content. These results reveal the potential use of self-healing vitrimers as integrated SHM systems capable of detecting damages and self-repairing autonomously. Full article
(This article belongs to the Special Issue Advanced Sensors Using Smart Materials)
Show Figures

Graphical abstract

22 pages, 7764 KiB  
Article
Dynamic Characterization of a Low-Cost Fully and Continuously 3D Printed Capacitive Pressure-Sensing System for Plantar Pressure Measurements
by Andrew T. Gothard, Jacob W. Hott and Steven R. Anton
Sensors 2023, 23(19), 8209; https://doi.org/10.3390/s23198209 - 30 Sep 2023
Viewed by 1051
Abstract
In orthopedics, the evaluation of footbed pressure distribution maps is a valuable gait analysis technique that aids physicians in diagnosing musculoskeletal and gait disorders. Recently, the use of pressure-sensing insoles to collect pressure distributions has become more popular due to the passive collection [...] Read more.
In orthopedics, the evaluation of footbed pressure distribution maps is a valuable gait analysis technique that aids physicians in diagnosing musculoskeletal and gait disorders. Recently, the use of pressure-sensing insoles to collect pressure distributions has become more popular due to the passive collection of natural gait data during daily activities and the reduction in physical strain experienced by patients. However, current pressure-sensing insoles face the limitations of low customizability and high cost. Previous works have shown the ability to construct customizable pressure-sensing insoles with capacitive sensors using fused-deposition modeling (FDM) 3D printing. This work explores the feasibility of low-cost fully and continuously 3D printed pressure sensors for pressure-sensing insoles using three sensor designs, which use flexible thermoplastic polyurethane (TPU) as the dielectric layer and either conductive TPU or conductive polylactic acid (PLA) for the conductive plates. The sensors are paired with a commercial capacitance-to-voltage converter board to form the sensing system. Dynamic sensor performance is evaluated via sinusoidal compressive tests at frequencies of 1, 3, 5, and 7 Hz, with pressure levels varying from 14.33 to 23.88, 33.43, 52.54, and 71.65 N/cm2 at each frequency. Five sensors of each type are tested. Results show that all sensors display significant hysteresis and nonlinearity. The PLA-TPU sensor with 10% infill is the best-performing sensor with the highest average sensitivity and lowest average hysteresis and linearity errors. The range of average sensitivities, hysteresis, and linearity errors across the entire span of tested pressures and frequencies for the PLA-TPU sensor with 10% infill is 11.61–20.11·10−4 V/(N/cm2), 11.9–31.8%, and 9.0–22.3%, respectively. The significant hysteresis and linearity error are due to the viscoelastic properties of TPU, and some additional nonlinear effects may be due to buckling of the infill walls of the dielectric. Full article
(This article belongs to the Special Issue Advanced Sensors Using Smart Materials)
Show Figures

Figure 1

19 pages, 3215 KiB  
Article
Electrochemical Sensing Platform Based on Carbon Dots for the Simultaneous Determination of Theophylline and Caffeine in Tea
by Paola Di Matteo, Alessandro Trani, Martina Bortolami, Marta Feroci, Rita Petrucci and Antonella Curulli
Sensors 2023, 23(18), 7731; https://doi.org/10.3390/s23187731 - 07 Sep 2023
Viewed by 1037
Abstract
A simple and selective method for the determination of caffeine (CAF) and theophylline (THEO) has been developed for a glassy carbon electrode (GCE) modified with a composite including carbon dots (CDs) and chitosan (CS). To our knowledge, there are no previous studies that [...] Read more.
A simple and selective method for the determination of caffeine (CAF) and theophylline (THEO) has been developed for a glassy carbon electrode (GCE) modified with a composite including carbon dots (CDs) and chitosan (CS). To our knowledge, there are no previous studies that analyze a CDs-modified GCE for the presence of CAF and THEO. The electrochemical behavior of a GCE modified with a CDs-CS composite was studied in acidic medium by cyclic voltammetry (CV) and differential pulse voltammetry (DPV). Considering the sensor analytical parameters, the same linear concentrations range was found for CAF and THEO ranging from 1 × 10−5 to 5 × 10−3 mol L−1 with the same detection limit (LOD) of 1 × 10−6 mol L−1. The reproducibility and repeatability data were satisfactory in terms of RSD%. Moreover, the storage stability was evaluated, evidencing good results whatever the experimental conditions used. The developed sensor was applied for the simultaneous determination of CAF and THEO in tea and drug, and results were compared with those obtained with HPLC-ESI-MS in SIR mode as an independent method optimized on purpose. The electrochemical sensor presents the undoubled advantages in terms of cheapness, portability, and ease of use, since it does not require skilled personnel. Full article
(This article belongs to the Special Issue Advanced Sensors Using Smart Materials)
Show Figures

Figure 1

13 pages, 2652 KiB  
Article
Development of Fiber-Bragg-Grating-Integrated Artificial Embedded Tendon for Multifunctional Assessment of Temperature, Strain, and Curvature
by Robertson Pires-Junior, Anselmo Frizera, Carlos Marques and Arnaldo Leal-Junior
Sensors 2023, 23(17), 7332; https://doi.org/10.3390/s23177332 - 22 Aug 2023
Viewed by 766
Abstract
This paper presents the development and application of an optical fiber-embedded tendon based on biomimetic multifunctional structures. The tendon was fabricated using a thermocure resin (polyurethane) and the three optical fibers with one fiber Bragg grating (FBG) inscribed in each fiber. The first [...] Read more.
This paper presents the development and application of an optical fiber-embedded tendon based on biomimetic multifunctional structures. The tendon was fabricated using a thermocure resin (polyurethane) and the three optical fibers with one fiber Bragg grating (FBG) inscribed in each fiber. The first step in the FBG-integrated artificial tendon analysis is the mechanical properties assessment through stress–strain curves, which indicated the customization of the proposed device, since it is possible to tailor the Young’s modulus and strain limit of the tendon as a function of the integrated optical fibers, where the coated and uncoated fibers lead to differences in both parameters, i.e., strain limits and Young’s modulus. Then, the artificial tendon integrated with FBG sensors undergoes three types of characterization, which assesses the influence of temperature, single-axis strain, and curvature. Results show similarities in the temperature responses in all analyzed FBGs, where the variations are related to the heterogeneity on the polyurethane matrix distribution. In contrast, the FBGs embedded in the tendon presented a reduction in the strain sensitivity when compared with the bare FBGs (i.e., without the integration in the artificial tendon). Such results demonstrated a reduction in the sensitivity as high as 77% when compared with the bare FBGs, which is related to strain field distributions in the FBGs when embedded in the tendon. In addition, the curvature tests indicated variations in both optical power and wavelength shift, where both parameters are used on the angle estimation using the proposed multifunctional artificial tendon. To that extent, root mean squared error of around 3.25° is obtained when both spectral features are considered. Therefore, the proposed approach indicates a suitable method for the development of smart structures in which the multifunctional capability of the device leads to the possibility of using not only as a structural element in tendon-driven actuators and devices, but also as a sensor element for the different structures. Full article
(This article belongs to the Special Issue Advanced Sensors Using Smart Materials)
Show Figures

Figure 1

14 pages, 12249 KiB  
Article
Paintable Silicone-Based Corrugated Soft Elastomeric Capacitor for Area Strain Sensing
by Han Liu, Simon Laflamme and Matthias Kollosche
Sensors 2023, 23(13), 6146; https://doi.org/10.3390/s23136146 - 04 Jul 2023
Viewed by 1216
Abstract
Recent advances in soft polymer materials have enabled the design of soft machines and devices at multiple scales. Their intrinsic compliance and robust mechanical properties and the potential for a rapid scaling of the production process make them ideal candidates for flexible and [...] Read more.
Recent advances in soft polymer materials have enabled the design of soft machines and devices at multiple scales. Their intrinsic compliance and robust mechanical properties and the potential for a rapid scaling of the production process make them ideal candidates for flexible and stretchable electronics and sensors. Large-area electronics (LAE) made from soft polymer materials that are capable of sustaining large deformations and covering large surfaces and are applicable to complex and irregular surfaces and transducing deformations into readable signals have been explored for structural health monitoring (SHM) applications. The authors have previously proposed and developed an LAE consisting of a corrugated soft elastomeric capacitor (cSEC). The corrugation is used to engineer the directional strain sensitivity by using a thermoplastic styrene-ethylene-butadiene-styrene (SEBS). A key limitation of the SEBS-cSEC technology is the need of an epoxy for reliable bonding of the sensor onto the monitored surface, mainly attributable to the sensor’s fabrication process that comprises a solvent that limits its direct deployment through a painting process. Here, with the objective to produce a paintable cSEC, we study an improved solvent-free fabrication method by using a commercial room-temperature-vulcanizing silicone as the host matrix. The matrix is filled with titania particles to form the dielectric layer, yielding a permittivity of 4.05. Carbon black powder is brushed onto the dielectric and encapsulated with the same silicone to form the conductive stretchable electrodes. The sensor is deployed by directly painting a layer of the silicone onto the monitored surface and then depositing the parallel plate capacitor. The electromechanical behavior of the painted silicone-cSEC was characterized and exhibited good linearity, with an R2 value of 0.9901, a gauge factor of 1.58, and a resolution of 70 με. This resolution compared well with that of the epoxied SEBS-cSEC reported in previous work (25 με). Its performance was compared against that of its more mature version, the SEBS-cSEC, in a network configuration on a cantilever plate subjected to a step-deformation and to free vibrations. Results showed that the performance of the painted silicone-sCEC compared well with that of the SEBS-cSEC, but that the use of a silicone paint instead of an epoxy could be responsible for larger noise and the under-estimation of the dominating frequency by 6.7%, likely attributable to slippage. Full article
(This article belongs to the Special Issue Advanced Sensors Using Smart Materials)
Show Figures

Figure 1

14 pages, 3851 KiB  
Article
Chemometric-Assisted Litmus Test: One Single Sensing Platform Adapted from 1–13 to Narrow pH Ranges
by Lisa Rita Magnaghi, Giancarla Alberti, Camilla Zanoni, Marta Guembe-Garcia, Paolo Quadrelli and Raffaela Biesuz
Sensors 2023, 23(3), 1696; https://doi.org/10.3390/s23031696 - 03 Feb 2023
Cited by 3 | Viewed by 1262
Abstract
A novel 3 × 4 colorimetric sensing platform, named the chemometric-assisted litmus test (CLT), has been developed by covalently anchoring commercial pH indicators to ethylene vinyl alcohol (EVOH). The proposed device can be exploited for pH determinations in a wide range from 1 [...] Read more.
A novel 3 × 4 colorimetric sensing platform, named the chemometric-assisted litmus test (CLT), has been developed by covalently anchoring commercial pH indicators to ethylene vinyl alcohol (EVOH). The proposed device can be exploited for pH determinations in a wide range from 1 to 13 and in specific narrow ranges, achieving sufficient accuracy and errors below 0.5 pH units. The experimental procedure is simple, quick and reliable; equilibration is reached in less than 2 h, CLT pictures are acquired by a camera, and data treatment is performed applying chemometric techniques such as principal component analysis (PCA) and partial least square regression (PLS) to RGB indices. Full article
(This article belongs to the Special Issue Advanced Sensors Using Smart Materials)
Show Figures

Figure 1

Planned Papers

The below list represents only planned manuscripts. Some of these manuscripts have not been received by the Editorial Office yet. Papers submitted to MDPI journals are subject to peer-review.

Title: A Low-Cost Fully 3D-Printed Capacitive Force Sensor for Plantar Pressure Measurements
Authors: Andrew T. Gothard1, Jacob W. Hott1, and Steven R. Anton1*
Affiliation: 1Dynamic and Smart Systems Laboratory, Department of Mechanical Engineering Tennessee Technological University, Cookeville, TN 38505
Abstract: The evaluation of footbed pressure distribution maps using pressure-sensing insoles has become a valuable gait analysis technique that aids physicians in diagnosing musculoskeletal and gait disorders. However, current pressure-sensing insoles face the limitations of low customizability and high cost. This work explores the feasibility of continuously printed capacitive pressure sensors for pressure-sensing insoles using three sensor designs. The designs use flexible thermoplastic polyurethane (TPU) as the dielectric and either conductive flexible thermoplastic polyurethane or conductive polylactic acid (PLA) for the conductive plates. Dynamic sensors performance is evaluated via sinusoidal compressive tests at frequencies of 1, 3, 5, and 7 Hz, with pressure levels varying from 15 to 25, 35, 55, and 75 N/cm2 at each frequency.

Title: Paintable Silicone-based Corrugated Soft Elastomeric Capacitor for Strain Sensing
Authors: Han Liu1, Simon Laflamme1,2, Matthias Kollosche3
Affiliation: 1 Department of Civil, Construction, and Environmental Engineering, Iowa State University, Ames, IA, USA 2 Department of Electrical and Computer Engineering, Iowa State University, Ames, IA, USA 3 Harvard John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, USA
Abstract: The authors have previously proposed and developed corrugated soft elastomeric capacitor (cSEC) based on styrene-ethylene-butadiene-styrene (SEBS) to create large-area strain sensors. A key limitation of the technology is in the required use of an epoxy to adhere the sensor onto the monitored surface, mainly attributable to the use of toluene in the sensor's fabrication that limits its direct deployment through a painting process. Here, we study an improved solvent-free fabrication method. The new cSEC is fabricated using a silicone matrix filled with Titania particles to form the dielectric, and with the same silicone but filled with carbon black particles to form the electrodes. The sensing performance of the silicone-based cSEC is characterized and its performance when directly painted onto a monitored surface assessed.

Back to TopTop