Wearable PPG Sensor Matrix for Cardiovascular Assessment

Abstract

Wearable biomonitoring systems and smart textiles
for healthcare are gaining more importance and significance in
the R&D sphere due to their potentials in healthcare and sports.
Such biomonitoring systems offer a number of advantages in
comparison to the conventional equipment proving mobility of
the wearer during a long-term monitoring of vital parameters.
There are different options to set up the physiological monitoring
using wireless and wearable technologies. One of the scenarios is
addressing textiles as a carrier of electronics. Moreover, those
differ by their functional applications, registered physiological
parameters and technology solutions. Still, the most demanded
biomonitoring smart systems focus on the examination of
cardiovascular conditions due to the urgency of the problem in
the public health. Furthermore, cardiovascular and
haemodynamic parameters are initial physiologic criteria in
sports physiology and in individual training. The common
method for cardiovascular assessment is registration of heart
electric potentials. Nevertheless, this research addresses
photoplethmography (PPG) as an optional approach to acquire
the information on cardiovascular and hemodynamic activity.
The aim of the study is to develop a textile integrated optical
sensor matrix for telemetric cardiovascular assessment. Two
reflectance sensors with single and multiple photodiodes (PDs)
based on a novel signal conversion were designed and adopted to
textiles. Designed prototypes were evaluated for their technical
parameters and biomonitoring performance in rest conditions.
The acquired physiological data was analyzed by the custom
developed software and compared to the reference data obtained
by the medical ECG monitor. Overall, the textile adopted
wearable systems with both types of PPG sensors have
demonstrated high signal accuracy and potentials for wearable
applications.