Fig 3 - uploaded by Afonso Raposo
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Flash as light source and rear camera as light detector (left) and display as light source and front camera as light detector (right).
Source publication
Non-expensive methods for measuring heart rate and oxygen saturation are of great importance in the scope of the COVID-19 outbreak to follow up on the symptoms and help to control the disease.Smartphones are widely available and their cameras can be used to acquire relevant physiological data, such as Photo-plethysmography (PPG) signals. Covering a...
Contexts in source publication
Context 1
... this work, the first method was studied, since it is the most robust for free-living usage. The typical approach in smartphones uses the flash LED as a white light source and the back camera as a light detector [2], [3], [4], as shown in Figure 3 (left). Another approach uses the screen as a light source and the front-facing camera as a light sensor [5], Figure 3 (right). ...
Context 2
... typical approach in smartphones uses the flash LED as a white light source and the back camera as a light detector [2], [3], [4], as shown in Figure 3 (left). Another approach uses the screen as a light source and the front-facing camera as a light sensor [5], Figure 3 (right). Unlike the flash LED method that emits all wavelengths in the visible range, using the display as light source results in a narrower band of emitted wavelengths. ...
Citations
... It is worth mentioning that the BITalino has been widely used within the research community for EDA acquisitions using the BITalino EDA sensor (as used in this experiment) [37][38][39]41]. Furthermore, this device has also been used for PPG acquisitions in laboratory research contexts [42,43]. For these reasons, the BITalino was selected as the gold standard device for reference data acquisitions in this study. ...
Wearable devices have been shown to play an important role in disease prevention and health management, through the multimodal acquisition of peripheral biosignals. However, many of these wearables are exposed, limiting their long-term acceptability by some user groups. To overcome this, a wearable smart sock integrating a PPG sensor and an EDA sensor with textile electrodes was developed. Using the smart sock, EDA and PPG measurements at the foot/ankle were performed in test populations of 19 and 15 subjects, respectively. Both measurements were validated by simultaneously recording the same signals with a standard device at the hand. For the EDA measurements, Pearson correlations of up to 0.95 were obtained for the SCL component, and a mean consensus of 69% for peaks detected in the two locations was obtained. As for the PPG measurements, after fine-tuning the automatic detection of systolic peaks, the index finger and ankle, accuracies of 99.46% and 87.85% were obtained, respectively. Moreover, an HR estimation error of 17.40±14.80 Beats-Per-Minute (BPM) was obtained. Overall, the results support the feasibility of this wearable form factor for unobtrusive EDA and PPG monitoring.
