Sensing with Earables: A Systematic Literature Review and Taxonomy of Phenomena

Earables have emerged as a unique platform for ubiquitous computing by augmenting ear-worn devices with state-of-the-art sensing. This new platform has spurred a wealth of new research exploring what can be detected on a wearable, small form factor. As a sensing platform, the ears are less susceptible to motion artifacts and are located in close proximity to a number of important anatomical structures including the brain, blood vessels, and facial muscles which reveal a wealth of information. They can be easily reached by the hands and the ear canal itself is affected by mouth, face, and head movements. We have conducted a systematic literature review of 271 earable publications from the ACM and IEEE libraries. These were synthesized into an open-ended taxonomy of 47 different phenomena that can be sensed in, on, or around the ear. Through analysis, we identify 13 fundamental phenomena from which all other phenomena can be derived, and discuss the different sensors and sensing principles used to detect them. We comprehensively review the phenomena in four main areas of (i) physiological monitoring and health, (ii) movement and activity, (iii) interaction, and (iv) authentication and identification. This breadth highlights the potential that earables have to offer as a ubiquitous, general-purpose platform

Analysis and Quantification of Physical Fatigue in Automobile Drivers: A Biomedical Approach

Vehicular accidents from fatigue due to sleep-deprived driving are rapidly increasing among heavy vehicle drivers. Consequently, a critical analysis of drivers’ fatigue in real time, using established clinical parameters, and subsequent scoring is of dire need in automobile sector. Such a scoring system would be helpful in validating the fatigue detecting devices based on non-contact features that can be installed onboard. Therefore, this study aimed to analyze and quantify physical fatigue during sleep-deprived simulated driving and their utility in developing objective score for fatigue assessment. The genesis and progression of physical fatigue was also analyzed in apparently healthy and pathological condition such as tauopathy. In the first set of experiments, the behavioral changes, cognition and motor performance in response to induced fatigue was analyzed in αCAMK-II-4R tau (transgenic/Tg) mice model of tautopathy (n=24) and were compared with those of wild-type mice (n =24). The mice were subjected to Accelerated Rotarod Test (ART), Open Field Test (OFT), Elevated Plus Maze Test (EPMT), Light and Dark Transition Test (LDT) and Forced Swimming Test (FST) for a comprehensive motor and cognitive performance analysis. Results showed that, genesis and progress of fatigue followed similar trend under physiological condition and pathological condition like tauopathy although the signs and symptoms of physical fatigue in mice models of tauopathy were more pronounced compared to healthy ones. Thus, a fatigue score system developed on healthy individuals may also be applied on pathological conditions that make the subjects vulnerable to fatigue. Subsequently, to quantify the manifestations of physical fatigue, twelve seasoned drivers were subjected to simulated driving session for 30 h and electroencephalogram (EEG),electrocardiogram (ECG) and spirometer recordings were taken for each individual at 3h intervals. In addition, peripheral blood samples were collected and analyzed at 8 h intervals for random blood sugar (RBS), blood urea (BUN) and serum creatinine. Results revealed that, energy and entropy features of EEG showed significant discrimination across time points in α and θ-bands at Cz electrode. The power spectrum density of HF (high frequency) components of ECG decreased with advancing stress and fatigue indicating sympathetic predominance with severity in fatigue. Spirometer recording confirmed gradual decrease in FEV1/FVC ratio (Forced Expiratory Volume at 1stsec / Forced Vital Capacity) as fatigue progressed. On the other hand, all blood biomarkers increased with the progress of fatigue but RBS and creatinine showed better discrimination across time-points....