Design of the Heart Rate Measurement Module in a Telemonitoring Device for First Responders Deployed in Extreme Environments

Abstract

This paper presents results of the SIXTHSENSE project, a research and innovation action within the H2020 program, aiming to develop new methods for unobtrusive monitoring of first responders based on multimodal sensing. The goal is to determine Heart Rate signal from ECG recorded by a multi sensor smart patch in the specific conditions the first responders are facing on their deployments. In addition to the challenges commonly faced when processing ECG signals recorded by wearables in high intensity activities, the work presented tackles the issues of noise generated by active sensors collocated with the ECG electrodes. Furthermore, the ergonomic requirements of the targeted users, namely firefighters and mountain rescuers, imposed positioning the multi sensor smart patch on the user’s back, making the analysis of recorder ECG signal more challenging. Initial experiments were conducted to determine the optimal electrode position on the back for ECG recording, and the design of the patch that would allow robust measurement of the signals, while not impeding the user during intense physical activity.Analysis of different algorithms for ECG signal processing was performed, considering both the specific distortions for ECG signals recorded on the back, and the effects of active system modules on the acquisition, namely electrotactile stimulation and iontophoretic analyte extraction.The prosposed multi sensor patch design and processing algorithm are presented and demonstrated in experiments simulating relevant conditions for the application of interest.