AHFE Open AccessHuman Factors and Wearable Technologies
Editors: Tareq Ahram, Christianne Falcão
Topics: Wearable Technologies
Publication Date: 2022
ISBN: 978-1-958651-05-6
DOI: 10.54941/ahfe1001467
Articles
Real-Time Breath Pattern Detection from Helmet
In this paper, we developed a remote breath pattern from a helmet-mounted thermal sensor while providing real-time feedback from the head-up display on the helmet. We use Lucas-Kanade Tracking and the Fast Fourier Transform to estimate and display a subject’s breaths per minute and breathing waveform in an embedded systems environment. In addition to respiration rate (RR), our visualization shows the waveform of the subject’s breathing pattern, which provides real-time diagnostic information. Our system was able to predict respiration rate with high accuracy and stability in all trials of subjects wearing face masks, due to the heat-trapping effect of facial coverings. In the unmasked cases, the error rates are higher than the masked cases, due to the higher signal-to-noise ratio and other causes. In future work, we would like to focus on unmasked RR detection to improve accuracy and robustness with better color mapping from the raw data to pixel colors, improve the tracking accuracy, improve the thermal resolution, apply signal filters, and reduce the sampling region of interest that is more sensitively tracked and centered around the nostrils.
Yang Cai, Tomas Vancura, Haocheng Zheng, Lenny Weiss
Open Access
Article
Conference Proceedings
Designing wearables devices to build emotional relationships
The focus of this paper is designing wearable devices to support the emotional relationship between users. The research reflects that any attempt by designers to produce outcomes aimed at helping design wearable devices must be grounded in an understanding of emotional engagement, convenient access, and intimate interaction. Emotionally positive experiences can inspire attempts to develop rich experiential devices. The case is made through several student projects that deal with particulars rooted in human relationships.
Suresh Sethi
Open Access
Article
Conference Proceedings
University footballers’ preference for smart trousers
This paper describes the development of smart trousers for self-training purposes during Covid-19, based on the requirements of two footballers from a Taiwanese University team. The two professional athletes aimed to be able to adapt their play as a result of self-training data that would be received visually from the smart trousers. The researcher collected feedback via two interviews, undertaken during the design preparation and garment fitting phases to ensure the garment design would be ready for production.The semi-structured interview technique and Kawakita Jiro method were adopted by the researcher. Firstly, the study investigated the footballer’s preferred smart trouser design in interview. Secondly, smart trousers were developed as initial garment prototypes, both virtually and physically. Thirdly, after the two athletes had been fitted with and worn the trousers for self-training purposes, the researcher issued a questionnaire and conducted a second interview to collect wearer feedback. The results showed that using both emulator data for a virtual prototype and physical garment sample in the step of prototype development has high degree of accuracy to assist pattern-making, fitting and sizing. The users’ feedback focused on three issues: pocket size, comfort of hem stitching, and label position.
Ying-Chia Huang, Wei-Hao Yang
Open Access
Article
Conference Proceedings
Using Inertial Measurement Units (IMU) and Comparative Trajectory Analysis for Modeling Micro-level Human Motion Dysfunction
Ubiquitous sensing from smartphones and wearable devices has proven to be useful for applications ranging from sports to modern medicine. The aim of this paper is to propose a visualization framework to illustrate the points in time when a query trajectory is deviating the most from a reference trajectory. Validation is performed through the use of a novel post ACL reconstruction dataset. Validation is performed through wearable sensing data collected from 11 patients recovering from ACL reconstruction and 10 healthy participants. Results provide promising insights about how this method can be used to visualize anomalies in motion trajectories and to detect abnormal motion patterns.
Robert Gutierrez, Joe Hart, Laura Barnes, Mehdi Boukhechba
Open Access
Article
Conference Proceedings
Actigraphy vs Polysomnography measurements for sleep arousals
This study sought to better understand how actigraphy may be practically applied to interpret useful information about sleep arousals when used in future studies of home-based sleep. For this purpose, we analysed a small cohort of healthy adult’s sleep using polysomnographic (PSG) measurements and actigraphy.Significance: Used to evaluate objective measure of motility and rest, actigraphy is commonly applied to assess physiological sleep parameters. While PSG recordings of sleep physiology have been shown to provide high fidelity measurements of key sleep parameters, the portability, ease of set-up, and low participant burden make actigraphy advantageous for measuring sleep parameters over extended nights of home-based sleep. Despite the ready uptake of actigraphy for clinical sleep assessments, this modality has lower accuracy in detecting periods of wake (AW) and a high magnitude of false positives when detecting sleep [1]. Methods: Ten healthy adults (50% male:female, mean age 25.9±3.2 years) with no history of sleep pathology took part in the study over four/five nights of sleep. To remove confounding aspects related to sleep pathologies/co-morbidities, healthy participants were studied. Participants were provided with an Actiwatch Spectrum Pro (Phillips Respironics Inc) to wear nightly on their non-dominant (in all cases left) wrist. Actiware (V6.0.9) was utilised to collate, and score the actigraphy measurements, with all 15-second epochs scored as either ‘wake’ or ‘sleep’, and a pre-set activity threshold (‘medium’) selected on the basis of preliminary testing.At the same time, the participant underwent ambulatory PSG using a Nox A1 (Nox Medical) PSG system. This is a portable polysomnography device used in our local sleep clinic to capture in-home PSG metrics. Sleep metrics from the Nox A1 were scored visually by a highly experienced, clinical sleep technician using the Noxturnal Software System (Vsn 6.0, Nox Medical), according to international scoring guidelines. Scoring was based on 15-second epochs and arousals lasting longer than this were considered ‘wake’. Analysis for this study focussed on comparison of arousal counts from PSG and actigraphy using Pearson linear correlation.Discussion of Results: A total of 41 nights of sleep measurements were collected. To better understand the relationship between PSG- and actigraphy-measured arousals, and mindful that the Actiwatch was worn on the left arm, customised arousal scoring for: 1) AA arousals (all scored physiological arousals); 2) LMA arousals (only physiological arousals that included a left arm movement); were scored. Spearman correlation analysis showed a significant, low-strength, positive relationship (rho=0.314, p=0.045) between PSG AA and Actiwatch awakenings, and sensitivity and specificity were calculated as 97% and 37%, respectively when comparing LMA with awakenings. However, a significant, high-strength, positive relationship (rho=0.660, p<0.001) was observed between PSG LMA and Actiwatch awakenings with increased specificity of 58%. This strong agreement between LMA arousals and actigraphy awakenings highlighted the utility of actigraphy in measuring sleep related arousals, although caution is needed when interpreting physiological ‘body-related’ awakenings vs limb-related motility associated with physiological awakenings. The low user cost associated with actigraphy for long-term home-based sleep studies, makes it a preferred alternative to PSG, and study results will assist to interpret actigraphy-based data in future studies of other populations.[1] Paquet et al, 2007. Sleep, 30(10), 1362-1369
Judith Paige Little, Selina Ho, Lionel Rayward, Glenice Uhrle, Daniel Green, Mark Pearcy
Open Access
Article
Conference Proceedings
Automation of the Collection and Processing of Physiological Functions from Wearable Sensors
The current period is evidence of the massive replacement of human strength by the results of the mental cognitive work of researchers. To cope with this situation, it is necessary to examine the impact of these technologies on the quality of life in the work and home environment when introducing new technologies. The main purpose of this work will be the collection of physiological functions such as heart rate in real-time from wearable sensors by creating an application that automatically collects sensor data. The work also proposes a mobile application that will be able to read the sensor data from the database and display it. The data from the sensors will be later used in a complex system and its proposal will also be described in this paper. Such a system could be used in many industries, like the automotive industry, industrial factories, smart homes and even education.
Kristian Fodor, Zoltán Balogh
Open Access
Article
Conference Proceedings
Affective computing for stress, anxiety and cybersickness detection in virtual reality
The prevalence of stress and anxiety has increased dramatically in recent decades, especially with the global COVID-19 pandemic. In parallel, effective ways of objectively assessing and quantifying these conditions have continued to be explored. Affective computing is one such technique that has gained popularity recently, using physiological signals to interpret, and infer human emotion. Additionally, virtual reality (VR) is a rapidly developing tool with promising advancements in the health sciences. Given the emergence of new unobtrusive wearables and biosensors-instrumented VR headsets, the combined use of VR and affective computing has enabled the development of new immersive applications to objectively evaluate stress and anxiety. In this paper, we examine various affective computing methods that have been combined with VR with the goal of quantitatively measuring stress and anxiety levels. Additionally, we explore how affective computing has been used in the assessment of cybersickness. In particular, we surveyed current VR studies and summarized the most common physiological measurements used to characterize stress, anxiety, and cybersickness. Methods monitoring heart rate, skin conductance, muscle movement, and brain activity are described. We highlight the current challenges and propose opportunities for future research directions.Keywords: Stress, Anxiety, Affective Computing, Physiological Measurements, Virtual Reality (VR), Cybersickness
Belmir Jose De Jesus Junior, Tiago Henrique Falk, Yuvika Dandiwal, Helen Alemu
Open Access
Article
Conference Proceedings
Sensory Fusion for Remote Multi-body Temperature Monitoring
We present a prototype of the remote multi-body temperature screening system that uses an RGB-D camera for face tracking and distance measurement and a thermal imaging camera for temperature detection. An automated calibration algorithm is implemented based on the distance to the target, the ambient temperature, and a reference object. Our field tests include outdoor and in-vehicle body temperature monitoring. We found that face tracking and distance measurements help to improve the dynamic automatic remote body temperature monitoring. Wearing a face mask would impair face tracking, with sensor fusion of thermal, RGB, and depth data, we have reduced the false detection of faces. In addition to the indoor environment, we evaluated the system in extreme conditions, including multiple types of face masks, outdoor, vehicle checkpoints, and under a canopy. We found that the vehicle drive-through and canopy offer improved performance over outdoors.
Sean Hackett, Florian Alber, Haocheng Zheng, Yang Cai
Open Access
Article
Conference Proceedings
Assessing the Effect of a Powered Ankle Exoskeleton on Human Agility with Inertial Measurement Units
Human agility describes the capacity to quickly adjust body movements in response to the environment. This study quantifies agility through performance on 0º, 45º, 90º, and 180º turns on an outdoor agility course. Participants (n=17) walked the course while wearing an ankle exoskeleton in powered and unpowered states, and their own shoes before and after the exoskeleton trials. Agility was quantified using Inertial Measurement Units placed on the feet. All metrics varied significantly with turn type and exhibited larger effect sizes than with changes in condition. Stride duration moderately increased in both exoskeleton conditions on 0º, 45º, and 90º turns. On 180º turns, the unpowered exoskeleton moderately decreased radial acceleration while the powered exoskeleton moderately increased speed and tangential acceleration. The results suggest that the evaluated ankle exoskeleton would be unobtrusive for similar healthy young users in their daily environments. The methods propose a framework for further study of exoskeletons and agility in a broader set of users with additional exoskeleton systems.
Katelyn King, Sarah Gonzalez, Leia Stirling
Open Access
Article
Conference Proceedings
Measurement of Spine Curvature using Flexicurve Integrated with Machine Vision
Many Spinal disorders require medication and prolonged rehabilitation, which consist of physical exercise and posture control. During restoration, frequent monitoring of spine curvature is necessary. The professionals do not suggest the radiography method more frequently since it has harmful effects on our bodies. Flexicurve has been widely used in much research to measure spine curvature in the sagittal plane. However, the data extraction from Flexicurve are not standardized or the current methodology adopted is difficult and time-consuming. Researchers use a graph (by hand) based method to extract curvature data from Flexicurve. Changes in spine curvature measurements can lead to the wrong methodology for correcting it. So, it is necessary to automate the data collection while measuring spine curvature with Flexicurve. This study proposes a method to automatically record the spine curvature data using the machine vision technique.
Ramnaath M, Mounika D, Murali Subramaniyam, Seung Nam Min
Open Access
Article
Conference Proceedings
Design and Research of Flexible Wearable Medical Testing Equipment for Pregnant Women
Pregnant women, as a special group, bear the mission of nurturing and continuing human life. Pregnant women need to experience psychological and physiological changes in the tenth month of pregnancy. In the special "post-epidemic era", it is hard and unsafe for pregnant women to go to the hospital regularly for birth check-up. In order to make pregnant women have a better prenatal experience, our team wants to design a wearable device, which can monitor the fetal heart rate and the frequency of fetal movement, so that pregnant women can also realize routine detection of the fetal condition at home, and protect the growth health and safety of the fetus. In this design, questionnaire interview, literature search and collaborative story telling are used to deeply understand the pain points of pregnant women's antenatal examination, the development status of wearable devices for pregnant women at home and abroad, pregnant women's preferences and so on. Then, determine the product use process, product functional structure and product packaging. This design adopts cutting-edge technologies such as flexible sensors, and combines ergonomics and kansei engineering. The product obtains the data and information of pregnant women and fetuses, and then through sorting and analysis, the results are intuitively transmitted to pregnant women, pregnant women's relatives or doctors in the matching APP, so that users can clearly obtain the health data of pregnant women in real time. Realize early warning of physical abnormalities of infants and mothers, early warning and early treatment, so as to better protect the safety and health of pregnant women and fetuses during pregnancy. After the usability test, the interviewed pregnant women thought that the design had a certain effect.
Luoyu Fu, Peiqi Yi, Zikun Gao, Yan Gan
Open Access
Article
Conference Proceedings
Simultaneous assessment of upper limb usage and sedentary behavior time among white- and blue-collar workers using wrist-worn accelerometers
The use of wrist-worn accelerometers to perform assessment of physical activity features and posture recognition, has significantly increased in the last decades, but remains limited in ergonomic contexts. In particular, to our knowledge, no studies employed them to investigate symmetry of use of upper limb (UL) during actual work shifts, even though such information would be useful to identify potentially unbalanced use of dominant and non-dominant limb. In the present study we aimed to estimate intensity and symmetry of use of UL while, at the same time, analyzing the amount of time spent in sedentary behavior in workers engaged in physically demanding and sedentary tasks.2.MethodsTwenty-two full-time workers employed in a metalworking company were recruited for the study and divided into two groups (n=11 each) according to the task they usually performed as follows:1)Machine tools operators, who are required to perform several kinds of machining processes such as cutting, turning, milling, etc.2)Administrative staff, who spend most of their shift time on a desk, in a sitting position using a PC, mouse and keyboard. Upper limb activity was measured for 4 consecutive hours of a regular working shift using two wrist-worn tri-axial accelerometers (Actigraph GT3X-BT, Acticorp Co., USA). The raw accelerations were processed to calculate the following parameters:a) vector magnitude (VM) counts, a composite measure of the accelerometric counts on the three planes of motion;b) Bilateral Magnitude (BLM), which is the sum of the VM values of dominant and non-dominant limb;c) Use Ratio (UR): is the ratio between the minutes of use calculated for the non-dominant and the dominant limb respectively. UR = 1 indicates an equal use of dominant and non-dominant limb, while UR < 1 (>1) indicates longer periods of use for the dominant (non-dominant) limb;d) Magnitude Ratio (MR) is the natural logarithm of the ratio between the VM counts calculated for the non-dominant and the dominant limbs respectively. A value of MR = 0 indicates perfect symmetric use of both limbs in terms of movement intensity. MR < 0 (> 0) denotes higher intensity activity of the dominant (non-dominant) limb;e) Time spent in sedentary (sitting) behaviour calculated according to the procedure proposed by Straczkiewicz et al. (2020)We performed one-way MANCOVA and ANCOVA using the number of steps as covariate because the arm swing associated with walking represents a source of accelerometric counts. The independent variable was the group (i.e. machine tools operator or administrative staff), while the dependent variables were: 1.The three UL activity parameters (i.e., BLM, MR and UR); 2.The time spend in sedentary (sitting) behavior.The level of significance was set at p = 0.05 and the effect of size was assessed using the eta-squared coefficient. Univariate ANOVAs were carried out as a post-hoc test on the adjusted group means.3.ResultsAfter controlling for number of steps, MANCOVA detected a significant main effect of group on UL activity and symmetry parameters [F(3,17) = 5.512; p = 0.008 Wilks’ λ = 0.507; η2 = 0.493]. In particular, the follow-up analysis revealed that machine tool operators performed a more asymmetrical activity in favor of their dominant limb with respect to those engaged in office tasks both in terms of intensity (MR = -0.18 vs. -0.02, p=0.004) and minutes of use (UR = 0.89 vs. 0.99, p=0.001). As regards the sedentary behavior, the ANCOVA revealed that the administrative staff spent significantly longer time in sitting position with respect to machine tools workers (158 minutes vs. 70, p=0.021). This value represents approximately 66% of the monitoring period.4.Discussion and conclusionThe results obtained from the experimental analysis identified the existence of significant asymmetry in the machine tools workers in terms of both duration of UL use and activity intensity. In particular, their markedly higher intensity of use of dominant limb is probably due to the fact that during activities such as cutting, turning, milling, etc. the dominant arm tends to perform dynamic tasks, while the non-dominant is devoted more to stabilizing position by contrasting the forces imposed by the dominant limb. Also, as expected, they spend little time in sitting position (30% of the monitoring period) compared with administrative staff, which perform a typical sedentary work. The findings of the present study, although carried out on a restricted sample in terms of working activities and number of subjects tested, suggest that accelerometer-based data allow discriminating among important features of different job occupations, at the same time highlighting potentially harmful conditions associated with the asymmetrical use of the dominant and non-dominant limbs. This can be extremely important in properly planning suitable ergonomic interventions.
Micaela Porta, Bruno Leban, Massimiliano Pau
Open Access
Article
Conference Proceedings
Hypoglycemia Vehicle Detection System Using Non-Invasive Sensors Applying Both EEG And HRV Real Time Measures: Neuroergonomics Theoretical Design
During COVID 19 pandemic the global needs for online shopping, ride-sharing transportation, and food delivery services have been dramatically increased. The drivers who suffer from diabetes especially low blood sugar level (Hypoglycemia) are more likely at risk than others. Earlier literature has revealed that hypoglycemic issues in patients with diabetes are correlated with significant changes in scalp electroencephalography (EEG); signals amplitude (time domain) or power spectral density (frequency domain). In addition, Haret rate variability HRV which reflects the balance between the sympathetic and parasympathetic nervous system has been proven as one of the indicators of Hypoglycemia. The aim of this paper to propose a conceptual design of a Vehicle detection system using both EEG and HRV measures at the same time in real time feed using non-invasive sensors to reduce the potential of driver’s cognitive dysfunction.
Awad Aljuaid
Open Access
Article
Conference Proceedings
Human Gait Recognition Using Bag of Words Feature-Representation Method
In this paper, we propose a novel gait recognition method based on a bag-of-words feature representation method. The algorithm is trained, tested and evaluated on a unique human gait data consisting of 93 individuals who walked with comfortable pace between two end-points during two different sessions. To evaluate the effectiveness of the proposed model, the results are compared with the outputs of the classification using extracted features. As it is presented, the proposed method results in significant improvement accuracy compared to using common statistical features, in all the used classifiers.
Nasrin Bayat, Elham Rastegari, Qifeng Li
Open Access
Article
Conference Proceedings
Opportunities for Wearable Technology to Increase the Safety of Rail Sector Workers
Transport Canada’s Innovation Centre supports emerging transportation technologies to help ensure Canadians can benefit from a safe, secure, clean, and integrated transportation system. From the standpoint of safety in rail transportation, the Centre is interested investigating the viability of using wearable technologies to increase the safety of rail sector workers. Although wearable technologies have proven to be useful in other industries, their adoption in Canadian rail has yet to gain traction. This study aims to show that wearable technologies have the potential to increase the safety of rail sector workers and that further investigation of specific use cases could be valuable.To achieve the objectives of the study, FactorSafe Solutions, an Ottawa, Ontario based human factors consultancy, was contracted to collect and analyse relevant data from multiple sources and then to report on their findings. The data collection methods were three-fold: a literature and market review of known human factors considerations of trackside and yard workers and existing technologies that may be suited to address those considerations; an analysis of the past five years of reported rail occurrences found on the Transportation Safety Board’s Rail Occurrence Database System to determine the most common types of occurrences where wearable technologies may have mitigated the risk levels; and a series of interviews with subject matter experts from the rail industry as well as researchers in the field of rail safety and associated technologies to validate the previous findings as well as uncover new information.By synthesizing the analysed data from the three data collection tasks, it was concluded that there are 11 relevant occurrence types, the highest priority of which include non-main track derailments, non-main track collisions, and movements exceed limits of authority, for which yard and trackside workers could potentially benefit from the implementation of specific wearable technologies. The 11 occurrence types are spread across both the yard and tracksideenvironments and could potentially be addressed through a variety of different wearable technologies. An important conclusion of the study is that there is not likely to be a single solution to meet the needs of all workers, environments, or tasks.Finally, a research framework is proposed to guide Transport Canada’s Innovation Centre through the potential next steps. The framework includes foundational research to build on the knowledge of the prioritized use cases and technologies, pilot studies conducted in nonoperational simulated settings with small groups of participants, and then larger field trials to assess performance of the wearable technologies during actual operations. A key successfactor to the research framework is to engage with the rail industry to benefit from their knowledge and resources, including incorporating their safety management systems with a human factors risk assessment during pilot studies to ensure that the wearable technologies do not introduce new safety risks.
Adam Freed, Heather Colbert, Daniel Blais
Open Access
Article
Conference Proceedings
Comparative evaluation of cervical exoskeletons using IMUs
Musculoskeletal disorders and pain in the neck and shoulders are commonly reported in workers whose activities imply overhead tasks. Repetitive passive head support or traumatic movements of the neck can cause damage to the ligaments and tendons of this region, with mild to severe long-term consequences. Exoskeletons are one of the solutions to help workers and their evaluation requires scientific methods and protocols to prove their effectiveness and make recommendations (Crea et al., 2021) (De Bock et al., 2022). Cervical exoskeletons could therefore be a valuable ergonomic solution to reduce stress on the neck and shoulders. However, while the growth of exoskeleton technology has led to multiple systems available on the market, it is still difficult to objectively determine which type or model of neck exoskeleton is the best adapted for overhead work and if the user’s perception matches with biomechanical outcomes.In this randomized crossover design study, 8 participants (3 women) performed dynamic and static extensions of the head in sitting position without trunk support for a period of 3 minutes (then 3 minutes of rest) while wearing three different head/neck exoskeletons in comparison with a situation without an exoskeleton. This allowed us to evaluate comfort, utility, usability, safety and impact (AFNOR, 2017) (Giovanelli & Touchard, 2018). A solution, based on synchronized merger of wireless inertial sensors, EMG signals, Polar OH1+ optical heart rate sensor (Hettiarachchi et al., 2019) and videos of the task (Motion CAPTIV, TEA, France) (Peeters et al., 2019) was used to examine joint angles of the head and spine movements, the bioelectrical activity of the sternocleidomastoid muscle and heart rate. Further these biomechanical and physiological outcomes, the perception of intensity was assessed by the Borg scale (Meyer, 2014) : CR10 Scale for the cervical and lumbar spine as well by the Rated Perceived Exertion (RPE) Scale for the global level of activity.The synthesis of this comparative analysis was carried out and compiled in the form of a conceptual basis from the C-K theory (Hatchuel & Weil, 2003) from the analysis of the design logic of exoskeletons.The results of this comparative analysis showed differences in terms of comfort, utility, usability, safety depending on the design logic of the solutions tested, but also depending on the morphology of the testers.
Yonnel Giovanelli, Fréderic Puel, Camélia Mahdi, Arnaud Gouelle, William Bertucci
Open Access
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Conference Proceedings