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Abstract

Bluetooth earphones can facilitate communications among workers engaged in manual(e.g., professional driver)or visual tasks (e.g., security guard). If workers remove their Bluetooth earphones due to poor fit, then communication effectiveness will decline, especially during manual or visual tasks. (1) to identify which design properties of Bluetooth earphones can contribute to user comfort, and (2) to identify if person characteristics (i.e., gender and ear shapes in this study) are related to differences in comfort perception during earphone use. 198 participants were recruited for this study.Individuals used four models of Bluetooth earphones in randomized order while performing computer tasks and then completed questionnaires on comfort perception specifically designed for this study. The 2 × 3 × 4 mixed design analysis of variance (ANOVA) was conducted to investigate the effects of gender, ear shape, and model condition. Results: The results indicated that there were significant differences in model on comfort perception. For earplugs, the shape of the earphone and the elasticity of material are important ergonomic concerns to improve the comfort perception. In addition, the adjustable tail length is an important ergonomic design property for the ear-hook. The information gained in this study should be useful in improving the ergonomic fitness of Bluetooth earphones.

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... The investigation of fit and comfort perceptions is a significant aspect of designing ergonomic products, and many such studies have been conducted for various head-and ear-related products, e.g., inear wearables (Fu and Luximon, 2021;Wang et al., 2022;Chiu et al., 2014), earmuffs (Gerges, 2012;Hsu et al., 2004), helmets Skals et al., 2016;Zhang et al., 2022c), virtual reality headsets (Wang et al., 2020), and smart glasses (Kim et al., 2021;Du et al., 2022;Chang et al., 2014). Unfortunately, the quantified relationships between 3D ophthalmic anthropometric/product parameters and human perceptions of eyeglasses frames' comfort for ergonomic design are still underexplored. ...
... An investigation of the relationships between anthropometric parameters and prototype perceptions can provide guidelines for mass customization and personalization of ergonomic products (Chiu et al., 2014;Ebe and Griffin, 2000;Fu and Luximon, 2021). In this study, since there were two main attaching face components (nose pads and temple) affecting children's comfort perceptions, we focused on investigating the perceptions of position/ comfort of nose pads, fit/ comfort of temple, and overall comfort of eyeglasses. ...
... In the influence analysis results for users' gender, there were no significant differences in perceived position and comfort of nose pads or perceived fit of temple, which reflects previous studies of fit and comfort perceptions of in-ear wearables (Fu and Luximon, 2021;Chiu et al., 2014). In the analyses of the influence of users' previous eyeglasses wearing experience, there were no significant differences in perceived comfort of nose pads or perceived fit and comfort of the temples. ...
Article
Modeling the quantified relationships between anthropometric/product parameters and human perceptions provides research-driven guidelines for mass customization and personalization of ergonomic products. In particular, such models are critical for designing children’s eyeglasses; however, they are still underexplored. This study examined children’s comfort perceptions for eyeglasses with two variables (i.e., nose pads width and temple clamping force), and established quantified linkage models between subjective human perceptions and objective 3D anthropometric/product parameters. To the best of our knowledge, this is the first work to quantify these relationships for ergonomic eyeglasses design. A psychological experiment with thirdy child participants was performed, and our analyses showed that two eyeglasses variables significantly influenced the children’s comfort perceptions; static vs. dynamic conditions caused slight differences. The mathematical trendlines and trend surfaces established by our findings can estimate perceived component-specific and overall comfort scores based on 3D anthropometric/product parameters. This also allows for calculation of parameter’s allowances for sizing and grading eyeglasses while maintaining satisfactory comfort. Github: https://github.com/Easy-Shu/Eyeglasses_Comfort_Modelling
... Second, Liu (2008) [6] measured 200 ear dimensions and suggested the design dimensions of the earphones compared to the sample products, but the various human ear dimensions that affect wearing comfort were not considered by limiting the ear dimensions to the ear canal length. Third, Chiu et al. (2014) [8] conducted a study to evaluate the wearing comfort of Bluetooth earphones for 30 min in a given scenario. The difference in comfort, pain, and weight was investigated depending on the type of product, gender, ear, etc. ...
... Second, Liu (2008) [6] measured 200 ear dimensions and suggested the design dimensions of the earphones compared to the sample products, but the various human ear dimensions that affect wearing comfort were not considered by limiting the ear dimensions to the ear canal length. Third, Chiu et al. (2014) [8] conducted a study to evaluate the wearing comfort of Bluetooth earphones for 30 min in a given scenario. The difference in comfort, pain, and weight was investigated depending on the type of product, gender, ear, etc. ...
... For example, they replied that the lightest weight of 4 g was the most appropriate, but the heaviest weight of 7 g was the least appropriate. Since the ear area is more sensitive than other body parts [21], the difference between weights can be accurately recognized [8]. As the use of wireless earphones increases in the future, the wearing time and usage are expected to increase, so designs that reduce the weight of earphones are required. ...
Article
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The purpose of this study was to evaluate the wearing comfort of wireless earphones. In order to test the effects of ear dimensions with the product characteristics on wearing comfort, first, a total of six ear dimensions were selected. In addition, each ear dimension was classified into two groups using K-means clustering analysis. Second, four major factors related to wearing comfort (pain, pressure, comfort, and fixation) with four sample products were investigated, considering the characteristics of the product (kernel-type/open-type), operation method (touch-input/button-press), and shape. Finally, a total of 38 participants (23 men and 15 women) participated in the experiments. The results show that pain in the ear canal was low to the participants who had a long length of the ear canal–incisura intertragica, and the fixation of the ear canal was high in the participants with a long incisura intertragica–antitragus cluster. Compared to open-type products, kernel-type products put more pressure on the ear canal area, so the participants felt less comfortable. In terms of operation methods, operating products in touch-input types caused less pain than operating products in button-press types did. Overall, the factors affecting user satisfaction and wearing comfort determined in this study will serve as a basis for the future design of wireless earphone products.
... Multiple studies on the physical interaction between the ear and inear wearables have provided an understanding of measurement and physical comfort (Chiu et al., 2014;Fan et al., 2019;Fu and Luximon, 2022;Terroir et al., 2021;Wang et al., 2022), which found the connection between factors-such as size, tragus expansion angle caused by wearables -and discomfort. However, there are still gaps in research on the perception of pressure discomfort measurements in the ear, limited by experimental techniques and equipment. ...
... Fan et al. (2021b) discovered distinctions across a multitude of dimensions between men and women, based on the collection and examination of Chinese external auditory canal measurements. Previous studies (Chiu et al., 2014;Fu and Luximon, 2022;Lin et al., 2020) have also not established a significant correlation between perceptual variations in the ear region and gender. Most ear size measurements have been found to be positively correlated with age, weight and BMI (Fan et al., 2019). ...
Article
In an effort to mitigate the homogenization of in-ear wearables, designers have been focusing on finding new solutions to enhance user comfort. While the concept of pressure discomfort thresholds (PDT) in humans has been applied to product design, research on the auricular concha remains scarce. In this study, we conducted an experiment to measure the PDT at six points in the auricular concha of 80 participants. Our results showed that the tragus was the most sensitive area and that gender, symmetry, and Body Mass Index (BMI)had no significant effect on PDT. Based on these findings, we generated pressure sensitivity maps of the auricular concha to aid in the optimization of in-ear wearable design.
... Earphones and ear-related products are broadly used in daily life. The factors that influence the comforts of wearing these products have been studied in different research areas [1][2][3][4]. It has been proved that audiometric characteristics of the ear-related products would influence the comforts of wearing earphones [4]. ...
... It has been proved that audiometric characteristics of the ear-related products would influence the comforts of wearing earphones [4]. In terms of ergonomic consideration, the shape of the earphone and the elasticity of material were identified as important factors which were associated with the comfort perception [1]. A set of quantitative comfort indices were proposed for evaluating the earmuff comfort, which included the earmuff headband force, the earmuff temperature, and the earmuff weight [2]. ...
Conference Paper
Earphones and ear-related products are broadly used in daily life. The dimension of the earphone affects the fit of the products and further influences the comforts of users. Several studies were conducted to measure and to describe the morphology of the ear. However, the gauges and definitions of key dimensions varied across different studies and the measurements were not practical for ear-related products design. In this paper, we proposed a quick method to extract an earphone-related ear dimensions using two-dimensional (2D) image of the ear. In total, six dimensions would be calculated, including ear height, ear width, ear length, the height of cavum conchae, the width of cavum conchae, and earlobe height. The quick method to extract ear dimension is a practical way for determining the size system of earphone during product design.
... There are many factors that affect the user's comfort perception of wearable devices, which can be summarized from four aspects: the physical attributes of the product, intrinsic human factors, external environmental factors, and use scene and tasks. The physical attributes of the product include weight distribution, shape, contact area with the human body, material softness, hardness, breathability and thermal conductivity (Chiu et al., 2014;Park et al., 2019;Shimura et al., 2023). Intrinsic human factors include multi-channel information feedback, perceptual acuity of different body parts, variability in body size, and subjective cognitive bias (de Korte et al., 2012;Franz et al., 2012;Fu and Luximon, 2020). ...
Conference Paper
In recent years, the market for lightweight wearable devices for eye-, ear-, and wrist-worn has grown rapidly. For these lightweight wearable devices, comfort directly impacts consumer adoption. However, most of the existing literature on the comfort of wearable devices have focused on wearable computers that are large in size and weight, and there is still a lack of comprehensive insights for approaches to assess the comfort of lightweight wearable devices. The present study reviewed existing research on the comfort of lightweight wearable devices, discussed the characteristics and limitations of current comfort assessment approaches, and provided feasible directions for foreseeable more extensive comfort assessment research.
... to the material used, which are ergonomically important issues (Chiu, et al., 2014). ...
Article
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The use of headphones was accentuated starting from the year 2020, inserted in the online universe of meetings, conferences, congresses, lives, classes, and videos, in the home office system, due to social isolation, resource resulting from health recommendations, pandemic of Covid 19. The purpose of this work is based on the response of the survey carried out with users to assist the design when elaborating the headphones project, considering the usability and choice factors from the perspective of the user’s perception. Based on a literature review, a questionnaire was designed aimed at the perception of the fundamental requirements of the device, which led to essential factors directing future design projects, in which there is alignment between physical and cognitive ergonomics, aiming at comfort, usage satisfaction, and health of its users.
... However, past studies on the sense of fitness of ear related products were conducted with only one indicator which is simple satisfaction, without considering the complex and implicit feelings of human nature [3]. Also, studies only analyzed the sense of fitness on the earplugs, eliminating analysis on the sense of fitness for the remaining part of the headset [4]. ...
Article
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Chapter
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This study provides an accurate method for evaluating the fit of earphones, which could be used for establishing a linkage between interference/gap values with human perception. Seven commercial CAD software tools stood out and were explored for the analysis of the deviation between earphone and ear. However, the current deviation analysis method remains to be improved for earphone fit evaluation due to excessive points in the calculation (Geomagic Wrap and Siemens NX), lack of value on interference (Geomagic Control X), computation boundary required (Rapidform XOR/Redesign), repetitive computation with same points and inclined calculation line segment or even invalid calculation (Solidworks, Creo). Therefore, an accurate deviation analysis algorithm was promoted, which calculated the deviation between earphone and ear exactly and classified the interference set and gap set precisely. There are five main procedures of this algorithm, which are point cloud model pre-processing, the generation of distance vectors, the discrimination of interference set and gap set, the discrimination of validity, and statistical analysis and visualization. Furthermore, the usability and validity of the deviation analysis algorithm were verified through statistical analysis and comparing visual effects based on the earphone-wearing experiment. It is certified that the deviation analysis algorithm is appropriate for earphone fit evaluation and the eight indexes of this algorithm were proved to be related to subjective comfort scores. It is meaningful for ear-worn product fit analysis, design, and development phases.
Article
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Chapter
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Chapter
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A manikin for hearing aid and related acoustic research was designed with median human adult dimensions. Ear simulation matches the acoustic response with an auricle, an ear canal, and an eardrum that equal the median ear in dimensions, acoustic impedance and modes. Dimensions of torso and head are based on published anthropometric data, but the auricle is based on data obtained for this development. The ear canal and eardrum are adapted from the earlike coupler by Zwislocki. The ear entrance sound pressure was found to be relatively insensitive to surface or skin impedance of the head. Validating measurements show the manikin, designated KEMAR, to be like a median human in acoustic response to free fields. Subject Classification: 65.22, 65.80, 65.35,65.82.
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Age-related growth changes in the ear were analyzed by measuring the width and length of ears in 1,590 North American Caucasians between 1 year and 18 years of age. By 1 year, ear width reached 93.5% of adult size in both sexes, only 2.3 mm less than the mean value at 18 years. In contrast, ear length attained a developmental level of only 76.4% by 1 year in both sexes, requiring an increment five times greater (12.3 mm) to reach the size of the ear at 18 years of age. At 5 years, the developmental level in width (96.7%) was almost equal to that of an adult, while the length reached 86.6% in both sexes, and requires 8.2 additional millimeters to attain adult size. Annual growth increments in ear width are small, interrupted with a few periods of no growth. Ear length in males showed an early rapid growth rate (between 2 and 3 years); subsequent growth was generally limited, interrupted with short periods of no changes. The same growth pattern appeared in females. Ear width reached its mature size in males at 7 years and in females at 6 years; ear length matured in males at 13 years and in females at 12. At the time of maturation, the ear was shorter than at 18 years by a mean of 1.1 to 1.4 mm.
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The concepts of comfort and discomfort in sitting are under debate. There is no widely accepted definition, although it is beyond dispute that comfort and discomfort are feelings or emotions that are subjective in nature. Yet, beside several subjective methodologies, several objective methods (e.g. posture analysis, pressure measurements, electromyography (EMG) are in use to assess sitting comfort or discomfort. In the current paper a theoretical framework is presented, in which comfort and discomfort were defined and the hypothetical associations with underlying factors were indicated. Next, the literature was reviewed to determine the relationships between objective measures and subjective ratings of comfort and discomfort. Twenty-one studies were found in which simultaneous measures of an objective parameter and a subjective rating of comfort or discomfort were obtained. Pressure distribution appears to be the objective measure with the most clear association with the subjective ratings. For other variables, regarding spinal profile or muscle activity for instance, the reported associations are less clear and usually not statistically significant.
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The purposes of this study were (a) to determine lower extremity anthropometric and sensory factors that are related to differences in comfort perception of shoe inserts with varying shape and material and (b) to investigate whether shoe inserts that improve comfort decrease injury frequency in a military population. 206 military personnel volunteered for this study. The shoe inserts varied in arch and heel cup shape, hardness, and elasticity in the heel and forefoot regions. A no insert condition was included as the control condition. Measured subject characteristics included foot shape, foot and leg alignment, and tactile and vibration sensitivity of the plantar surface of the foot. Footwear comfort was assessed using a visual analog scale. Injury frequency was evaluated with a questionnaire. The statistical analyses included Student's t-tests for repeated measures, ANOVA (within subjects), MANOVA (within insert combinations), and chi-square tests. The average comfort ratings for all shoe inserts were significantly higher than the average comfort rating for the control condition. The incidence of stress fractures and pain at different locations was reduced by 1.5-13.4% for the insert compared with the control group. Foot arch height, foot and leg alignment, and foot sensitivity were significantly related to differences in comfort ratings for the hard/soft, the viscous/elastic, and the high arch/low arch insert combinations. Shoe inserts of different shape and material that are comfortable are able to decrease injury frequency. The results of this study showed that subject specific characteristics influence comfort perception of shoe inserts.
Article
The aim of this study was to reveal the anthropometric growth of auricula from birth to the age of 18 years and to bring out the dynamics of ear growth. A total of 1552 children in 50 groups were evaluated. Six surface measurements were performed directly on the right auricle of the subjects: the length from the superaurale to subaurale, the width from the tragus to helix, the width from the tragus to antihelix, the conchal depth, the height from the helix to mastoid at superauraler level, and the height from the helix to mastoid at tragal level. The frequency of prominent ear deformity and the degree of attachment of the lobule were also noted. Vertical auricular growth was complete in girls at the age of 11 and in boys at the age of 12, whereas the auricular width from the tragus to helix, the height from the helix to mastoid at superauraler level and the height from the helix to mastoid at tragal level were found almost complete at the age of 6. The auricular width from the tragus to antihelix attained its full size at 6 months for girls and 12 months for boys. The conchal depth was found almost complete at the age of 5 in both sexes. The incidence of prominent ear deformity and attached lobule was 9.8 and 26.5%, respectively. Different ear growth pattern and maturation size from previously published reports are obtained in different populations. There is still need for future studies comparing populations with different social and ethnic background to interpret common knowledge about the size of the ear. This study gives dimensional information and the growth pattern of the auricle, and therefore may reveal important implications for the adequate timing of the surgical treatment of auricular deformity.
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To design comfortable hand tools, knowledge about comfort/discomfort in using hand tools is required. We investigated which factors determine comfort/discomfort in using hand tools according to users. Therefore, descriptors of comfort/discomfort in using hand tools were collected from literature and interviews. After that, the relatedness of a selection of the descriptors to comfort in using hand tools was investigated. Six comfort factors could be distinguished (functionality, posture and muscles, irritation and pain of hand and fingers, irritation of hand surface, handle characteristics, aesthetics). These six factors can be classified into three meaningful groups: functionality, physical interaction and appearance. The main conclusions were that (1) the same descriptors were related to comfort and discomfort in using hand tools, (2) descriptors of functionality are most related to comfort in using hand tools followed by descriptors of physical interaction and (3) descriptors of appearance become secondary in comfort in using hand tools.
Article
To provide a database of the auricular measurements of Chinese infants born in Hong Kong. Prospective cross-sectional study. A total of 2384 healthy singleton, born consecutively at the Prince of Wales Hospital and the Union Hospital from October 1998 to September 2000, were included in the study. The range of gestation was 33-42 weeks. Measurements included ear width (EW), ear length (EL) and ear position (EP). The data show generally higher values for males in the parameters measured. When compared with previously published data for Caucasian and Jordanian term babies, Chinese babies have shorter EL. The ears were within normal position in nearly all our infants. The human ear appears to grow in a remarkably constant fashion. This study establishes the first set of gestational age-specific standard of the ear parameters for Chinese new-borns, potentially enabling early syndromal diagnosis. There are significant inter-racial differences in these ear parameters.
Article
To achieve mass customization and collaborative product design, human factors and ergonomics should play a key development role. The purpose of this study was to provide product designers with the anthropometic dimensions of outer ears for different demographic data, including gender and age. The second purpose was to compare the dimensions of various ear-related products (i.e., earphone, bluetooth earphone and ear-cup earphone) with the anthropometic database and recommend appropriate solutions for design. Two hundred subjects aged 20-59 was selected for this study and divided into four age stratifications. Further, three different dimensions of the outer ear (i.e., the earhole length, the ear connection length and the length of the pinna) were measured by superimposed grid photographic technique. The analysis of variance (ANOVA) was used to investigate the effects of gender, and age on ear dimensions. The results showed that all ear dimensions had significant gender effects. A comparison between the anthropometric dimensions and those of current products revealed that most current ear-related products need to be redesigned using anthropometric data. The shapes of earhole and pinna are not circular. Consequently, ear products need to be elongated so that users may feel more comfortably and not have the product slip off easily.
Article
This study was prompted by the prevalence of back injury and pain in the working population, particularly amongst workers who are increasingly exposed to sedentary work in industrialised countries, and the corresponding limited evidence regarding the effectiveness of seating designs currently used in the workplace. Objective: The purpose of this study was to investigate the differences in comfort, productivity, and posture between the Bambach saddle seat and a standard office chair (two chair designs used within the workplace today). A single system, multiple-baseline research design across a sample of four subjects was used. A withdrawal A1 B1 A2 B2 design was utilised, with the ordering of the sequence varying with each subject. "A" represented the standard office chair, and "B" the Bambach saddle seat. Discomfort ratings tended to increase over time regardless of the seat being used. However, while the saddle seat provided reduced levels of lower back discomfort, it demonstrated higher discomfort in the lower limbs, particularly the hips and buttocks. There were no significant differences identified in productivity between the two chairs. The saddle seat consistently promoted a greater trunk-to-thigh angle for all subjects, a position associated with optimum sitting posture. This study has implications for the treatment of low back injury and pain at work, as well as other daily activities that involve prolonged static sitting, such as those incorporated in self maintenance, leisure and rest activities. This study provides health professionals with a systematic investigation of the immediate effects of using both the Bambach saddle seat and standard office chair in sitting. The findings of this study should be considered in future research.
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Workers with disabilities are entitled to have their individual needs accommodated in a way that allows them to perform the essential duties of their job. However, adults with disabilities are often lacking in career development and are ill-prepared to negotiate workplace accommodations. This has led educators to seek workplaces that can accommodate the needs of adolescents with disabilities, so these adolescents can learn to negotiate accommodations and enhance their career development through work-based education. This paper reports on two case studies in which employers had agreed to accommodate the needs of adolescents with disabilities participating in work-based education. Social Cognitive Career Theory (SCCT) framed the analyses of these two cases - a case of a student with physical disabilities and a case of a student with developmental disabilities. SCCT proves valuable in understanding the role of work-based education in the career development of disabled youth.