Assistant Professor - Measurement, Instrumentation, and Sensors

Wireless shirt for physiological monitoring

The ability to monitor the health status of elderly patients or patients undergoing home therapy allows significant advantages in terms of cost and convenience of the subject. However, these non-clinical applications of biomedical signals acquisition require different monitoring devices having, between the other characteristics, reduced size, low power and environment compatibility.

The research activity concerns the development of a new wireless shirt for physiological monitoring that can monitor the main physiological parameters of a person in a non-invasive manner. All sensors have contactless characteristics that permit to avoid the direct contact with the skin. This system is a useful solution for monitoring the health condition of patients at home. The wireless shirt consists of two subsystems: first, a wearable data acquisition hardware, in which the sensors are integrated for the acquisition of biomedical parameters, and secondly, a remote monitoring station located separately and connected to Internet for telemedicine applications.

The physiological parameters that are monitored are electrocardiogram (ECG), heart rate (HR), derived from ECG signals through the determination of RR intervals, respiratory rate, and three-axis motion (acceleration and position) of the subject measured using an accelerometer. All sensors are designed using contactless measurement techniques, thus avoiding the use of gel for the conduction of the signal and possible skin irritation due to contact. The electrodes for measuring ECG signal are capacitive, while the measure of respiration is obtained by plethysmography, which does not require direct contact with skin. In order to design and construct the signal acquisition circuits in an efficient and simple manner, modular design concept is adopted in this research. The flexible signal conditioning modules are designed and assembled together. The human parameters can be recorded and analyzed continuously during work activities at home. The correct evaluation of these parameters allows the medical staff to assess to the state of health, to know accidental injury or other danger occurred in patients at home.