The peaks and valleys of the pressure and RIP signals were automatically identified and used to flag a change in the direction of chest movements, as well as calculate the timing and duration of individual inhalation and exhalation segments.
Only local peaks that were greater than 2 pressure units above or below a previous one were flagged to avoid finding many rapid ‘breaths’ in a noisy signal .
The overlap between labeled inspiration segments of the three signals were measured both with and without adjusting for the ∆T value. Shifting the delayed signal improves the overlap percentage and brings the pressure to RIP overlap to within 11% of the overlap between the RIP bands. Table suggests that when corrected for ∆T delay, the direction change is synchronized. RESULTS
FUTURE WORKS Future work will focus on chest movement analysis and determine particular monitoring needs of older adults in the smart home context.
An unobtrusive pressure sensor array beneath the mattress to determine the duration of each inspiration phase, expiration phase and initiation time of each movement.
cross-correlation was used to align signals from a pressure array, and local signal peaks were detected to identify chest wall movements from two types of sensors.
convenient assessments and long-term monitoring of population groups with a greater prevalence of lung and respiratory disorders through passive and discrete sensors.
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