Research

22 pages, 7552 KiB

Open AccessArticle

Automated and Continuous Fatigue Monitoring in Construction Workers Using Forearm EMG and IMU Wearable Sensors and Recurrent Neural Network

by Srikanth Sagar Bangaru, Chao Wang and Fereydoun Aghazadeh

Sensors 2022, 22(24), 9729; https://0-doi-org.brum.beds.ac.uk/10.3390/s22249729 - 12 Dec 2022

Cited by 10 | Viewed by 2671

Abstract

About 40% of the US construction workforce experiences high-level fatigue, which leads to poor judgment, increased risk of injuries, a decrease in productivity, and a lower quality of work. Therefore, it is essential to monitor fatigue to reduce its adverse effects and prevent [...] Read more.

About 40% of the US construction workforce experiences high-level fatigue, which leads to poor judgment, increased risk of injuries, a decrease in productivity, and a lower quality of work. Therefore, it is essential to monitor fatigue to reduce its adverse effects and prevent long-term health problems. However, since fatigue demonstrates itself in several complex processes, there is no single standard measurement method for fatigue detection. This study aims to develop a system for continuous workers’ fatigue monitoring by predicting the aerobic fatigue threshold (AFT) using forearm muscle activity and motion data. The proposed system consists of five modules: Data acquisition, activity recognition, oxygen uptake prediction, maximum aerobic capacity (MAC) estimation, and continuous AFT monitoring. The proposed system was evaluated on the participants performing fourteen scaffold-building activities. The results show that the AFT features have achieved a higher accuracy of 92.31% in assessing the workers’ fatigue level compared to heart rate (51.28%) and percentage heart rate reserve (50.43%) features. Moreover, the overall performance of the proposed system on unseen data using average two-min AFT features was 76.74%. The study validates the feasibility of using forearm muscle activity and motion data to workers’ fatigue levels continuously. Full article

(This article belongs to the Special Issue Environmental and Workplace Monitoring for the Assessment of Occupational Risks and Worker Comfort)

► Show Figures

Figure 1

15 pages, 2417 KiB

Open AccessArticle

Long-Term Assessment of a Set of CO₂ Concentration Sensors in an In-Use Office Building

by Carmen Serrano Lapuente, Héctor Herrada, María José Jiménez and María Nuria Sánchez

Sensors 2022, 22(23), 9403; https://0-doi-org.brum.beds.ac.uk/10.3390/s22239403 - 02 Dec 2022

Cited by 1 | Viewed by 1277

Abstract

The measurement of the CO₂ concentration has a wide range of applications. Traditionally, it has been used to assess air quality, with other applications linked to the experimental assessment of occupancy patterns and air renewal rates. More recently, the worldwide dissemination of [...] Read more.

The measurement of the CO₂ concentration has a wide range of applications. Traditionally, it has been used to assess air quality, with other applications linked to the experimental assessment of occupancy patterns and air renewal rates. More recently, the worldwide dissemination of COVID-19 establishing a relationship between infection risk and the mean CO₂ level has abruptly led to the measurement of the CO₂ concentration in order to limit the spread of this respiratory disease in the indoor environment. Therefore, the extensive application of this measurement outside of traditional air quality assessment requires an in-depth analysis of the suitability of these sensors for such modern applications. This paper discusses the performance of an array of commercial wall-mounted CO₂ sensors, focusing on their application to obtain occupancy patterns and air renovation rates. This study is supported by several long-term test campaigns conducted in an in-use office building located in south-eastern Spain. The results show a spread of 19–101 ppm, with a drift of 28 ppm over 5 years, an offset of 2–301 ppm and fluctuations up to 80 ppm in instantaneous measurements not related to concentration changes. It is proposed that values averaged over 30 min, using a suitable reference value, be used to avoid erroneous results when calibration is not feasible. Full article

(This article belongs to the Special Issue Environmental and Workplace Monitoring for the Assessment of Occupational Risks and Worker Comfort)

► Show Figures

Figure 1

26 pages, 7829 KiB

Open AccessArticle

Human Error Prediction Using Heart Rate Variability and Electroencephalography

by Nahoko Takada, Tipporn Laohakangvalvit and Midori Sugaya

Sensors 2022, 22(23), 9194; https://0-doi-org.brum.beds.ac.uk/10.3390/s22239194 - 26 Nov 2022

Cited by 2 | Viewed by 1757

Abstract

As human’s simple tasks are being increasingly replaced by autonomous systems and robots, it is likely that the responsibility of handling more complex tasks will be more often placed on human workers. Thus, situations in which workplace tasks change before human workers become [...] Read more.

As human’s simple tasks are being increasingly replaced by autonomous systems and robots, it is likely that the responsibility of handling more complex tasks will be more often placed on human workers. Thus, situations in which workplace tasks change before human workers become proficient at those tasks will arise more frequently due to rapid changes in business trends. Based on this background, the importance of preventing human error will become increasingly crucial. Existing studies on human error reveal how task errors are related to heart rate variability (HRV) indexes and electroencephalograph (EEG) indexes. However, in terms of preventing human error, analysis on their relationship with conditions before human error occurs (i.e., the human pre-error state) is still insufficient. This study aims at identifying biological indexes potentially useful for the detection of high-risk psychological states. As a result of correlation analysis between the number of errors in a Stroop task and the multiple HRV and EEG indexes obtained before and during the task, significant correlations were obtained with respect to several biological indexes. Specifically, we confirmed that conditions before the task are important for predicting the human error risk in high-cognitive-load tasks while conditions both before and during tasks are important in low-cognitive-load tasks. Full article

(This article belongs to the Special Issue Environmental and Workplace Monitoring for the Assessment of Occupational Risks and Worker Comfort)

► Show Figures

Figure 1

16 pages, 3758 KiB

Open AccessArticle

Validation of an Embedded Motion-Capture and EMG Setup for the Analysis of Musculoskeletal Disorder Risks during Manhole Cover Handling

by Rémy Hubaut, Romain Guichard, Julia Greenfield and Mathias Blandeau

Sensors 2022, 22(2), 436; https://0-doi-org.brum.beds.ac.uk/10.3390/s22020436 - 07 Jan 2022

Cited by 13 | Viewed by 3402

Abstract

Musculoskeletal disorders in the workplace are a growing problem in Europe. The measurement of these disorders in a working environment presents multiple limitations concerning equipment and measurement reliability. The aim of this study was to evaluate the use of inertial measurement units against [...] Read more.

Musculoskeletal disorders in the workplace are a growing problem in Europe. The measurement of these disorders in a working environment presents multiple limitations concerning equipment and measurement reliability. The aim of this study was to evaluate the use of inertial measurement units against a reference system for their use in the workplace. Ten healthy volunteers conducted three lifting methods (snatching, pushing, and pulling) for manhole cover using a custom-made tool weighting 20 and 30 kg. Participants’ back and dominant arm were equipped with IMU, EMG, and reflective markers for VICON analysis and perception of effort was estimated at each trial using a Visual Analog Scale (VAS). The Bland–Altman method was used and results showed good agreement between IMU and VICON systems for Yaw, Pitch and Roll angles (bias values < 1, −4.4 < LOA < 3.6°). EMG results were compared to VAS results and results showed that both are a valuable means to assess efforts during tasks. This study therefore validates the use of inertial measurement units (IMU) for motion capture and its combination with electromyography (EMG) and a Visual Analogic Scale (VAS) to assess effort for use in real work situations. Full article

(This article belongs to the Special Issue Environmental and Workplace Monitoring for the Assessment of Occupational Risks and Worker Comfort)

► Show Figures

Figure 1

12 pages, 1421 KiB

Open AccessArticle

Assessing Post-Driving Discomfort and Its Influence on Gait Patterns

by Marko M. Cvetkovic, Denise Soares and João Santos Baptista

Sensors 2021, 21(24), 8492; https://0-doi-org.brum.beds.ac.uk/10.3390/s21248492 - 20 Dec 2021

Cited by 1 | Viewed by 2633

Abstract

Professional drivers need constant attention during long driving periods and sometimes perform tasks outside the truck. Driving discomfort may justify inattention, but it does not explain post-driving accidents outside the vehicle. This study aims to study the discomfort developed during driving by analysing [...] Read more.

Professional drivers need constant attention during long driving periods and sometimes perform tasks outside the truck. Driving discomfort may justify inattention, but it does not explain post-driving accidents outside the vehicle. This study aims to study the discomfort developed during driving by analysing modified preferred postures, pressure applied at the interface with the seat, and changes in pre- and post-driving gait patterns. Each of the forty-four volunteers drove for two hours in a driving simulator. Based on the walking speed changes between the two gait cycles, three homogeneous study groups were identified. Two groups performed faster speeds, while one reduced it in the post-steering gait. While driving, the pressure at the interface and the area covered over the seat increased throughout the sample. Preferred driving postures differed between groups. No statistical differences were found between the groups in the angles between the segments (flexed and extended). Long-time driving develops local or whole-body discomfort, increasing interface pressure over time. While driving, drivers try to compensate by modifying their posture. After long steering periods, a change in gait patterns can be observed. These behaviours may result from the difficulties imposed on blood circulation by increasing pressure at this interface. Full article

(This article belongs to the Special Issue Environmental and Workplace Monitoring for the Assessment of Occupational Risks and Worker Comfort)

► Show Figures

Figure 1

16 pages, 3165 KiB

Open AccessArticle

Monitoring and Assessment of Indoor Environmental Conditions after the Implementation of COVID-19-Based Ventilation Strategies in an Educational Building in Southern Spain

by Antonio J. Aguilar, María L. de la Hoz-Torres, Mª Dolores Martínez-Aires and Diego P. Ruiz

Sensors 2021, 21(21), 7223; https://0-doi-org.brum.beds.ac.uk/10.3390/s21217223 - 30 Oct 2021

Cited by 22 | Viewed by 2801

Abstract

Since students and teachers spend much of their time in educational buildings, it is critical to provide good levels of indoor environmental quality (IEQ). The current COVID-19 pandemic has shown that maintaining a good indoor air quality level is an effective measure to [...] Read more.

Since students and teachers spend much of their time in educational buildings, it is critical to provide good levels of indoor environmental quality (IEQ). The current COVID-19 pandemic has shown that maintaining a good indoor air quality level is an effective measure to control the transmission of the SARS-CoV-2 virus. This study used sensors to monitor key IEQ factors and assess several natural ventilation scenarios in a classroom of the University of Granada. Subsequently, the IEQ factors (temperature, relative humidity, CO₂ concentration, acoustic environment, and air velocity) were evaluated for the selected ventilation scenarios in the occupied classroom, and the field monitoring was carried out in two different assessment periods, winter and summer. The obtained results show that the CO₂ concentration levels were well below the recommended limits. However, the maintenance of the recommended thermal and acoustic IEQ factors was significantly affected by the natural ventilation strategies (temperature and relative humidity values were very close to the outside values, and the background sound pressure level was over 35 dBA during the entire assessment). The proper measurements and careful selection of the appropriate ventilation scenarios become of utmost importance to ensure that the ventilation rates required by the health authorities are achieved. Full article

(This article belongs to the Special Issue Environmental and Workplace Monitoring for the Assessment of Occupational Risks and Worker Comfort)

► Show Figures

Graphical abstract

22 pages, 4660 KiB

Open AccessArticle

An Internet of Things and Fuzzy Markup Language Based Approach to Prevent the Risk of Falling Object Accidents in the Execution Phase of Construction Projects

by María Martínez-Rojas, María José Gacto, Autilia Vitiello, Giovanni Acampora and Jose Manuel Soto-Hidalgo

Sensors 2021, 21(19), 6461; https://0-doi-org.brum.beds.ac.uk/10.3390/s21196461 - 27 Sep 2021

Cited by 11 | Viewed by 2856

Abstract

The Internet of Things (IoT) paradigm is establishing itself as a technology to improve data acquisition and information management in the construction field. It is consolidating as an emerging technology in all phases of the life cycle of projects and specifically in the [...] Read more.

The Internet of Things (IoT) paradigm is establishing itself as a technology to improve data acquisition and information management in the construction field. It is consolidating as an emerging technology in all phases of the life cycle of projects and specifically in the execution phase of a construction project. One of the fundamental tasks in this phase is related to Health and Safety Management since the accident rate in this sector is very high compared to other phases or even sectors. For example, one of the most critical risks is falling objects due to the peculiarities of the construction process. Therefore, the integration of both technology and safety expert knowledge in this task is a key issue including ubiquitous computing, real-time decision capacity and expert knowledge management from risks with imprecise data. Starting from this vision, the goal of this paper is to introduce an IoT infrastructure integrated with JFML, an open-source library for Fuzzy Logic Systems according to the IEEE Std 1855-2016, to support imprecise experts’ decision making in facing the risk of falling objects. The system advises the worker of the risk level of accidents in real-time employing a smart wristband. The proposed IoT infrastructure has been tested in three different scenarios involving habitual working situations and characterized by different levels of falling objects risk. As assessed by an expert panel, the proposed system shows suitable results. Full article

(This article belongs to the Special Issue Environmental and Workplace Monitoring for the Assessment of Occupational Risks and Worker Comfort)

► Show Figures

Graphical abstract

21 pages, 4069 KiB

Open AccessArticle

Analysis of Impact of Natural Ventilation Strategies in Ventilation Rates and Indoor Environmental Acoustics Using Sensor Measurement Data in Educational Buildings

by María L. de la Hoz-Torres, Antonio J. Aguilar, Diego P. Ruiz and María Dolores Martínez-Aires

Sensors 2021, 21(18), 6122; https://0-doi-org.brum.beds.ac.uk/10.3390/s21186122 - 12 Sep 2021

Cited by 12 | Viewed by 3454

Abstract

Indoor environmental conditions can significantly affect occupants’ health and comfort. These conditions are especially important in educational buildings, where students, teachers and staff spend long periods of the day and are vulnerable to these factors. Recently, indoor air quality has been a focus [...] Read more.

Indoor environmental conditions can significantly affect occupants’ health and comfort. These conditions are especially important in educational buildings, where students, teachers and staff spend long periods of the day and are vulnerable to these factors. Recently, indoor air quality has been a focus of attention to ensure that disease transmission in these spaces is minimised. In order to increase the knowledge in this field, experimental tests have been carried out to characterise the impact of natural ventilation strategies on indoor air quality and the acoustic environment. This study has evaluated three ventilation scenarios in four different classrooms in buildings of the University of Granada, considering different window and door opening configurations. Ventilation rates were estimated using the CO₂ Decay Method, and background noise recordings were made in each classroom for acoustic tests. Results show that specific natural ventilation strategies have a relevant impact that is worth considering on the background noise in indoor spaces. In this sense ventilation rates provided by the different configurations varied between 3.7 and 39.8 air changes per hour (ACH) and the acoustic tests show a background noise ranging from 43 to 54 dBA in these scenarios. Consequently, managers and teachers should take into account not only the ACH, but also other collateral impacts on the indoor environmental conditions such as the thermal comfort or the acoustic environment. Full article

(This article belongs to the Special Issue Environmental and Workplace Monitoring for the Assessment of Occupational Risks and Worker Comfort)

► Show Figures

Figure 1

Journal Menu

Journal Browser

Environmental and Workplace Monitoring for the Assessment of Occupational Risks and Worker Comfort

Share This Special Issue

Special Issue Editors

Special Issue Information

Keywords

Published Papers (8 papers)

Research

Further Information

Guidelines

MDPI Initiatives

Follow MDPI