|
Fibre Bragg grating (FBG) optical fibre sensors provide highly sensitive measurements of mechanical movements of the skin surface. However, state of the art interrogators are bulky, bench top components that are not compatible with long term, ambulatory monitoring. We are interested in continuous blood pressure monitoring. The standard techniques for blood pressure measurements face several difficulties due to the continuous measurement of blood pressure requires an invasive procedure by arterial catheterisation, whereas the standard non-invasive devices do not provide a continuous reading.
The wearable/ambulatory FBG interrogator consists of a miniature interrogator (FiSpec FBG X100, FiSens, Rolleiwerke GmbH) and a microcontroller (ESP32 WROOM 32D, Espressif, Shanghai) communicated using UART, then signal information transmitted is parsed in the microcontroller and streamed in a web application via Wi-Fi. The power management of the device uses batteries with a typical cycle life of 300 – 500 (charge, discharge cycles). Using this device, the movement in blood vessels due to pulsatile blood flow synchronous to the cardiac cycle was measured in a human participant. Moreover Pulse Transit Time (PTT) measurements for continuous blood pressure were performed in a cardiovascular phantom.
|
