Submit to Sensors Review for Sensors Propose a Special Issue

Journal Browser

State-of-the-Art Sensors Technology in Sweden

Print Special Issue Flyer
Special Issue Editors
Special Issue Information
Published Papers

A special issue of Sensors (ISSN 1424-8220). This special issue belongs to the section "State-of-the-Art Sensors Technologies".

Deadline for manuscript submissions: closed (30 June 2021) | Viewed by 18891

Share This Special Issue

Special Issue Editor

Dr. Nebojsa Malesevic

E-Mail Website
Guest Editor

Department of Biomedical Engineering, Faculty of Engineering, Lund University, 223 63 Lund, Sweden
Interests: electrical stimulation; sensory feedback; rehabilitation; motor control; biomedical signal processing; machine learning
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

In the current age of the fourth industrial revolution, advancement related to the efficiency and the effectiveness of any new process, method, and device is backed by the development of specialized sensors. New sensors that can accurately and robustly measure specific physical properties are key components for designing optimal process control. Thus, the number and diversity of sensors that could be found in modern manufacturing processes, medical equipment, automotive industry, transportation, robotics, and modern technology in general, is in constant expansion. Furthermore, as personal consumer technology and assistive devices rapidly evolved in the previous decade, various sensors, made with the purpose of intimate interaction between man, machine, and surroundings, have become an integral part of our lives.

Considering that Sweden, as one of the most highly industrialized countries, actively promotes technological advances in all fields, this Special Issue will address all types of sensors made by Swedish companies, research and innovation centers, and academia.

Dr. Nebojsa Malesevic
Guest Editor

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.

Published Papers (6 papers)

Download All Papers

Research

13 pages, 2869 KiB

Open AccessArticle

Modified Thermocouple Sensor and External Reference Junction Enhance Accuracy in Indoor Air Temperature Measurements

by Hans Lundström and Magnus Mattsson

Sensors 2021, 21(19), 6577; https://doi.org/10.3390/s21196577 - 01 Oct 2021

Cited by 3 | Viewed by 3166

Abstract

Indoor air temperature belongs to the most important climatic variables in indoor climate research, affecting thermal comfort, energy balance, and air movement in buildings. This paper focuses on measurement errors when using thermocouples in indoor temperature measurements, with special attention on measurements of air temperature. We briefly discuss errors in thermocouple measurements, noting that, for temperatures restricted to indoor temperature ranges, a thermocouple Type T performs much better than stated in “standards”. When thermocouples are described in the literature, industrial applications are primarily considered, involving temperatures up to several hundred degrees and with moderate demands on accuracy. In indoor applications, the temperature difference between the measuring and the reference junction is often only a few degrees. Thus, the error contribution from the thermocouple itself is almost immeasurable, while the dominant error source is in the internal reference temperature compensation in the measuring instrument. It was shown that using an external reference junction can decrease the measurement error substantially (i.e., down to a few hundredths of a degree) in room temperature measurements. One example of how such a device may be assembled is provided. A special application of room temperature measurements involves measuring indoor air temperature. Here, errors, due to radiation influence on the sensor from surrounding surfaces, were surprisingly high. The means to estimate the radiative influence on typical thermocouples are presented, along with suggestions for modification of thermocouple sensors to lower the radiation impact and thereby improve the measurement accuracy. Full article

(This article belongs to the Special Issue State-of-the-Art Sensors Technology in Sweden)

► Show Figures

Figure 1

12 pages, 4453 KiB

Open AccessArticle

Signal Quality Assessment of a Novel ECG Electrode for Motion Artifact Reduction

by Hesam Halvaei, Leif Sörnmo and Martin Stridh

Sensors 2021, 21(16), 5548; https://doi.org/10.3390/s21165548 - 18 Aug 2021

Cited by 5 | Viewed by 2600

Abstract

Background: The presence of noise is problematic in the analysis and interpretation of the ECG, especially in ambulatory monitoring. Restricting the analysis to high-quality signal segments only comes with the risk of excluding significant arrhythmia episodes. Therefore, the development of novel electrode technology, robust to noise, continues to be warranted. Methods: The signal quality of a novel wet ECG electrode (Piotrode) is assessed and compared to a commercially available, commonly used electrode (Ambu). The assessment involves indices of QRS detection and atrial fibrillation detection performance, as well as signal quality indices (ensemble standard deviation and time–frequency repeatability), computed from ECGs recorded simultaneously from 20 healthy subjects performing everyday activities. Results: The QRS detection performance using the Piotrode was considerably better than when using the Ambu, especially for running but also for lighter activities. The two signal quality indices demonstrated similar trends: the gap in quality became increasingly larger as the subjects became increasingly more active. Conclusions: The novel wet ECG electrode produces signals with less motion artifacts, thereby offering the potential to reduce the review burden, and accordingly the cost, associated with ambulatory monitoring. Full article

(This article belongs to the Special Issue State-of-the-Art Sensors Technology in Sweden)

► Show Figures

Figure 1

20 pages, 24628 KiB

Open AccessArticle

A Sensing System Based on Public Cloud to Monitor Indoor Environment of Historic Buildings

by Zhongjun Ni, Yu Liu, Magnus Karlsson and Shaofang Gong

Sensors 2021, 21(16), 5266; https://doi.org/10.3390/s21165266 - 04 Aug 2021

Cited by 6 | Viewed by 3095

Abstract

Monitoring the indoor environment of historic buildings helps to identify potential risks, provide guidelines for improving regular maintenance, and preserve cultural artifacts. However, most of the existing monitoring systems proposed for historic buildings are not for general digitization purposes that provide data for smart services employing, e.g., artificial intelligence with machine learning. In addition, considering that preserving historic buildings is a long-term process that demands preventive maintenance, a monitoring system requires stable and scalable storage and computing resources. In this paper, a digitalization framework is proposed for smart preservation of historic buildings. A sensing system following the architecture of this framework is implemented by integrating various advanced digitalization techniques, such as Internet of Things, Edge computing, and Cloud computing. The sensing system realizes remote data collection, enables viewing real-time and historical data, and provides the capability for performing real-time analysis to achieve preventive maintenance of historic buildings in future research. Field testing results show that the implemented sensing system has a 2% end-to-end loss rate for collecting data samples and the loss rate can be decreased to 0.3%. The low loss rate indicates that the proposed sensing system has high stability and meets the requirements for long-term monitoring of historic buildings. Full article

(This article belongs to the Special Issue State-of-the-Art Sensors Technology in Sweden)

► Show Figures

Figure 1

14 pages, 9194 KiB

Open AccessArticle

Electrotactile Feedback for the Discrimination of Different Surface Textures Using a Microphone

by Pamela Svensson, Christian Antfolk, Anders Björkman and Nebojša Malešević

Sensors 2021, 21(10), 3384; https://doi.org/10.3390/s21103384 - 12 May 2021

Cited by 8 | Viewed by 2005

Abstract

Most commercial prosthetic hands lack closed-loop feedback, thus, a lot of research has been focusing on implementing sensory feedback systems to provide the user with sensory information during activities of daily living. This study evaluates the possibilities of using a microphone and electrotactile feedback to identify different textures. A condenser microphone was used as a sensor to detect the friction sound generated from the contact between different textures and the microphone. The generated signal was processed to provide a characteristic electrical stimulation presented to the participants. The main goal of the processing was to derive a continuous and intuitive transfer function between the microphone signal and stimulation frequency. Twelve able-bodied volunteers participated in the study, in which they were asked to identify the stroked texture (among four used in this study: Felt, sponge, silicone rubber, and string mesh) using only electrotactile feedback. The experiments were done in three phases: (1) Training, (2) with-feedback, (3) without-feedback. Each texture was stroked 20 times each during all three phases. The results show that the participants were able to differentiate between different textures, with a median accuracy of 85%, by using only electrotactile feedback with the stimulation frequency being the only variable parameter. Full article

(This article belongs to the Special Issue State-of-the-Art Sensors Technology in Sweden)

► Show Figures

Figure 1

21 pages, 56646 KiB

Open AccessArticle

Textile Electrodes: Influence of Knitting Construction and Pressure on the Contact Impedance

by Luisa Euler, Li Guo and Nils-Krister Persson

Sensors 2021, 21(5), 1578; https://doi.org/10.3390/s21051578 - 24 Feb 2021

Cited by 30 | Viewed by 5028

Abstract

Textile electrodes, also called textrodes, for biosignal monitoring as well as electrostimulation are central for the emerging research field of smart textiles. However, so far, only the general suitability of textrodes for those areas was investigated, while the influencing parameters on the contact impedance related to the electrode construction and external factors remain rather unknown. Therefore, in this work, six different knitted electrodes, applied both wet and dry, were compared regarding the influence of specific knitting construction parameters on the three-electrode contact impedance measured on a human forearm. Additionally, the influence of applying pressure was investigated in a two-electrode setup using a water-based agar dummy. Further, simulation of an equivalent circuit was used for quantitative evaluation. Indications were found that the preferred electrode construction to achieve the lowest contact impedance includes a square shaped electrode, knitted with a high yarn density and, in the case of dry electrodes, an uneven surface topography consisting of loops, while in wet condition a smooth surface is favorable. Wet electrodes are showing a greatly reduced contact impedance and are therefore to be preferred over dry ones; however, opportunities are seen for improving the electrode performance of dry electrodes by applying pressure to the system, thereby avoiding disadvantages of wet electrodes with fluid administration, drying-out of the electrolyte, and discomfort arising from a “wet feeling”. Full article

(This article belongs to the Special Issue State-of-the-Art Sensors Technology in Sweden)

► Show Figures

Figure 1

22 pages, 7979 KiB

Open AccessArticle

Calibrating Range Measurements of Lidars Using Fixed Landmarks in Unknown Positions

by Anas Alhashimi, Martin Magnusson, Steffi Knorn and Damiano Varagnolo

Sensors 2021, 21(1), 155; https://doi.org/10.3390/s21010155 - 29 Dec 2020

Cited by 1 | Viewed by 2007

Abstract

We consider the problem of calibrating range measurements of a Light Detection and Ranging (lidar) sensor that is dealing with the sensor nonlinearity and heteroskedastic, range-dependent, measurement error. We solved the calibration problem without using additional hardware, but rather exploiting assumptions on the environment surrounding the sensor during the calibration procedure. More specifically we consider the assumption of calibrating the sensor by placing it in an environment so that its measurements lie in a 2D plane that is parallel to the ground. Then, its measurements come from fixed objects that develop orthogonally w.r.t. the ground, so that they may be considered as fixed points in an inertial reference frame. Moreover, we consider the intuition that moving the distance sensor within this environment implies that its measurements should be such that the relative distances and angles among the fixed points above remain the same. We thus exploit this intuition to cast the sensor calibration problem as making its measurements comply with this assumption that “fixed features shall have fixed relative distances and angles”. The resulting calibration procedure does thus not need to use additional (typically expensive) equipment, nor deploy special hardware. As for the proposed estimation strategies, from a mathematical perspective we consider models that lead to analytically solvable equations, so to enable deployment in embedded systems. Besides proposing the estimators we moreover analyze their statistical performance both in simulation and with field tests. We report the dependency of the MSE performance of the calibration procedure as a function of the sensor noise levels, and observe that in field tests the approach can lead to a tenfold improvement in the accuracy of the raw measurements. Full article

(This article belongs to the Special Issue State-of-the-Art Sensors Technology in Sweden)

► Show Figures

Figure 1

Journal Menu

Journal Browser

State-of-the-Art Sensors Technology in Sweden

Share This Special Issue

Special Issue Editor

Special Issue Information

Published Papers (6 papers)

Research

Further Information

Guidelines

MDPI Initiatives

Follow MDPI