In recent years, research on sensory ear-worn devices ("earables") explored measuring body temperature at different locations in and around the ears. While the tympanic membrane (eardrum) is a well-established medical gold-standard position, earables face challenges integrating body temperature sensors because of the limited space available, the diversity of earphone designs, and the obstruction of the eardrum by the audio hardware components. Therefore, to understand the trade-offs in accuracy between different sensor positions in and around the ears, we contribute the first systematic comparison of locations around the ear. Based on related work, existing earable form factors, and a pre-study with thermal ear images from four subjects, we selected five positions to compare to tympanic temperature: concha, ear canal and three positions spread behind the ear. Subsequently, we developed a custom earable with six optical temperature sensors that can measure all positions simultaneously. In a study with 12 participants at room temperature and settled isothermal conditions, we find that compared to the tympanic membrane, the mean temperature difference was 0.30 degrees C colder at the concha (sufficient according to American Society for Testing and Materials) and ear canal, and 0.6 degrees C colder at positions behind the ear. Exposing participants to varying environmental conditions and physical movements resulted in unreliable measurements which could not be calibrated.
Making a body-worn device wearable is a deceptively difficult challenge: it is not enough to make a functional device and simply put it on the body; it must also work with the wearer to create a positive body-product relationship. In order for a body-mounted device to achieve true wearability, proper attention must also be paid to a multitude of additional questions, including things like device size, mass, rigidity, comfort, aesthetics, and other critical design criteria above and beyond raw functionality. This paper reviews papers from the International Symposium on Wearable Computing (ISWC) and the Journal of Interactive, Mobile, Wearable and Ubiquitous Technologies (IMWUT) to understand the extent to which these professional communities acknowledge and incorporate fundamental questions of wearability into their work. The results found that while wearability is relatively present in the literature (84.44% of ISWC papers, 74.54% of IMWUT papers), there are many papers that fail to address wearability with the appropriate scientific rigor assuming they do address wearability at all. These results demonstrate the need for the wearables community to recognize the functional importance of wearability and its necessity to the design process.
One of the often overlooked features of wearable physiological sensing devices is the possibility for institutions to observe and manage the health and well-being of a group of people. For example, a school could use wearables to monitor for increased levels of stress or sickness within the student body. The accuracy and utility of current sensing devices make this possible. However, in real-world settings, many users do not use devices consistently or correctly. Moreover, institutional monitoring of individuals raises privacy concerns. In this study, we use real-world data to identify periods of cyclical stress in a cohort of 103 Japanese university students while preserving each student's privacy. We observe heightened waking heart rate (HR) and maximum waking HR, alongside corroborating evidence from sleep HR, sleep heart rate variability (HRV), activity patterns, and sleep phases, during periods coinciding with significant academic and societal events, suggesting clear associations with stress. We show the feasibility of detecting collective changes in stress biomarkers within a cohort using consumer wearables.
Emerging wearable construction toolkits offer new avenues for hands-on learning through an accessible and creative making process. This paper uses an on-skin wearable prototyping toolkit in hands-on workshops with a total of 45 middle-school students aged between 11 and 15. Besides investigating the effectiveness of utilizing the on-skin toolkit to foster creativity, we iteratively designed and optimized the workshop format, which consists of a hands-on tutorial, a group-making process, and a presentation of project prototypes. Our findings suggest positive engagement and interest in the making process from the middle-school students who participated in the on-skin wearable workshop.
Transportation mode detection (TMD) for wheelchair users is essential for applications that facilitate enhancing accessibility and quality of life. Yet, the lack of extensive datasets from disabled individuals hinders the development of tailored TMD systems. Our study assesses two data collection methods in TMD for disability research: using non-wheelchair users to simulate wheelchair activities (Simulation Real IMU) and generating synthetic sensor data from videos (Virtual IMU). Results show that, when using a larger dataset and multiple sensor modalities, models trained on Simulation Real IMU perform better. However, models trained on both Simulation Real IMU and Virtual IMU exhibited similar performances when sensors were restricted to accelerometer and gyroscope only. This finding guides future researchers toward the use of Simulation Real IMU for comprehensive, multimodal sensor studies, provided they have sufficient budget and time. However, the more cost and time-efficient Virtual IMU can be a viable alternative in scenarios using basic sensors.
