Design and development of custom wearable systems for respiratory and joint motion monitoring

In the last decades, wearable technology has gained momentum in the framework of monitoring physiological parameters and joint motion due to their advantages in terms of cost-effectiveness, ease of use, comfortability, and portability. They allow people to be more aware of their health status on a daily basis and allow them to be more inclined towards prevention reducing the burden for care centers and hospitals. In addition to reducing the health costs, they enable an early detection of diseases and optimize their treatment, thus improving the outcomes of the therapy and the life quality, and fostering a healthy lifestyle In this context, wearable systems for health monitoring represent a valuable and cost-effective alternative to standard devices expanding their application to other scenarios such as occupational settings, sports, and home monitoring in which they are unable to operate. In addition, these systems allow to continuously and remotely monitor the parameters of interest throughout the day. Furthermore, they can be designed to be patient-tailored, by developing personalized solutions based on the patient’s needs. The present dissertation positions itself within the stream of research on wearable systems based on conductive-based strain sensors employed for monitoring physiological parameters and joint motion. It aims at presenting innovative approaches to developing wearable systems based on conductive sensors for monitoring respiratory activity and joint motion. For monitoring the respiratory activity, solutions based on detecting the chest wall motion are proposed. Special attention is reported to define a guideline for optimizing the number of sensors and their position on the chest wall depending on the application of interest. In addition, a novel manufacturing process for the employed sensors is presented to overcome some limitations (e.g., sensitivity to external influencing factors) and enhance their reliability and robustness, obtaining a multi-purpose sensor usable with different wearable supports. The remainder of this work is structured as follows: Chapter 1 presents the background of this dissertation, the reference technologies for monitoring the parameters of interest, and defines the context of the research topic. Chapter 2 proposes the description of the state-of-the-art sensing technology employed to instrument wearable systems for monitoring the respiratory activity and joint motion with particular attention to resistive sensors. Chapter 3 proposes the design, fabrication, and feasibility assessment of wearable systems based on conductive sensors developed during these three years of research. Chapter 4 discusses the main challenges, issues and future improvements for wearable systems based on conductive sensors for monitoring respiratory activity and joint motion.