# Trimodal Watch-Type Wearable Health Monitoring Device
###### Abstract  
In the domain of healthcare, wearable health monitoring devices have emerged as essential tools for the advancement of patient health tracking. These devices facilitate the provision of real-time medical data to clinicians, enabling early diagnosis, timely intervention, and enhanced management of individual health. This study introduces an innovative trimodal wearable health monitoring device in the form of a wristwatch. The device integrates a breath analyzer for the assessment of gaseous phase biomarkers, a sweat analyzer for the evaluation of aqueous-phase biomarkers, and an infrared sensor for the measurement of body temperature in the optical phase. Engineered on a compact 3 cm \(\times\) 3 cm printed circuit board, the device has been optimized for wearability, power efficiency, and seamless integration with both wired and wireless charging and communication systems. Furthermore, custom software applications, designed for both Windows and Android platforms, have been developed to facilitate intuitive data visualization and storage on personal computers and smartphones. Empirical results from real-time chemical testing substantiate the device's efficacy and potential as an advanced solution for wearable health monitoring. wearable health monitoring; trimodal sensing; embedded system; point-of-care testing; real-time biomarker detection; health tracking +
Footnote †: journal: Medical  
increasingly utilized for the surveillance of various health metrics, including heart rate, respiratory rate, and physical activity levels. Multi-mode detection in wearable health monitoring devices involves the integration of diverse sensors and technologies to concurrently monitor multiple health parameters, thereby augmenting functionality and versatility. For example, aqueous phase detection in these devices is engineered to analyze various biomarkers present in bodily fluids such as sweat, saliva, and tears [3; 4; 5; 6; 7]. These systems are particularly advantageous for non-invasive health surveillance, providing continuous, real-time data on physiological metrics, including glucose levels for diabetes management, dopamine for stress and hormonal regulation, and other critical biomarkers. Conversely, gaseous phase detection is designed to measure and analyze gasses exhaled or emitted from the body, offering valuable insights into an individual's health status. Such devices are capable of detecting volatile organic compounds (VOCs), carbon dioxide (CO\({}_{2}\)), oxygen (O\({}_{2}\)), and other gasses, which act as indicators of metabolic and physiological processes [7; 8; 9; 10; 11] and assist in managing respiratory conditions such as asthma and COPD [8]. Additionally, optical phase detection employs light-based technologies to measure physiological parameters including heart rate, blood oxygen saturation, body temperature, and, in some cases, blood pressure [12; 13]. To date, no existing studies have demonstrated the ability to conduct trimodal measurements--incorporating gaseous, aqueous, and optical phase analyses--within a single device. We posit that implementing multi-modal detection is crucial for comprehensive monitoring of patient-generated symptoms, facilitating accurate diagnostics, and catering to a diverse array of users across various demographics and clinical contexts [14; 15]. This study presents proof of concept for an innovative trimodal wearable health monitoring device that incorporates gaseous, aqueous, and infrared sensor, within a single compact wristband form factor, enabling the provision of real-time data for early diagnosis and enhanced health management. The device is optimized for low-power consumption and includes an intuitive graphical user interface (GUI) for Windows and a dedicated smartphone application, ensuring user accessibility. To validate the device's efficacy, the gaseous phase is evaluated through the detection of VOCs, the aqueous phase is assessed by measuring dopamine levels, and the optical phase is tested via body temperature assessment.