Vital EKG: a wearable multi-sensor system for medical diagnostics and patient monitoring

Continuous vital signs monitoring is of utmost importance for many people. Consequently, devices able to perform such monitoring, also called Personal Health System (PHS), have been gaining a lot of research and market interest in the last few years. This thesis work deals with the design of a comprehensive PHS able to perform EKG, measure heart rate (HR) and blood oxygen saturation (SpO2) as well as monitoring skin temperature and humidity and tracking activity. Vital EKG has a wrist band form factor. This choice simplifies the management of the device with respect to chest straps; EKG trace and SpO2 and HR readings are offered on demand and require the user to place two fingers on the device. Vital EKG has been designed using off the shelf, modern Surface Mount Technology (SMT) components. The layout of a Semi-Flex Printed Circuit Board (PCB) is also considered to account for assembly in the 3D printed case. HR and SpO2 measurements accuracy have been checked against a professional Vital Sign Simulator; furthermore, real-life tests have been performed and results have been confronted with a professional Fingertip Pulse Oximeter. EKG traces provided by Vital EKG have been tested as well against professional medical equipment. To sum up, further studies could use hardware and firmware developed in this work to provide detailed informations about anomalies of the heart, such as atrial fibrillation.