The article highlights the integration of wearable technology in patient care and how these devices are reshaping healthcare delivery and enhancing the monitoring of vital signs.

Because of the COVID-19 pandemic's effects on the planet, remote vital sign monitoring and healthcare services are now critically necessary. The measurement of body temperature, heart rate, and blood oxygen level is vital for both illness management and appropriate medical attention.

What are wearable devices?

Wearable devices (WD), often called "wearables," offer users hands-free functionality to carry out various tasks, including recording personal data like fitness and health information. A part of the wider Internet of Things (IoT) ecosystem, wearables allow connected devices to communicate and function independently.

What is the role of wearable devices in healthcare?

WD has sensors that use electrical impulses to identify physiological signs. The application of wearable biomedical sensors for medical use has grown significantly in the past decade, aiming at real-time vital sign monitoring to treat chronic conditions. 

One of the most important vital signs to evaluate a patient's health is their body temperature. It offers vital details regarding a patient's state and can reveal the existence of a disease or infection.

Standard Framework of Wearable Device for Measuring Temperature

This article discusses a wireless device created to measure body temperature using the National Digital Observatory of Smart Environments (OBNiSE), part of the Center for Research, Innovation, and Technological Development at the University of the Valley of Mexico (CIIDETEC-UVM).

The OBNiSE framework is an organized system that lets you monitor and build smart systems for making IoT-based solutions. It also ensures that large amounts of data are managed securely and efficiently at different levels.

Proposed Framework of Wearable Devices

The six levels that make up the OBNiSE architecture, as shown in Fig. 1, have distinct functions, which are as follows:

Fig 1 Framework of the wearable device. Source: MDPI

Device or Physical layer

The physical layer gathers all of the sensor data. The WD, as shown in Fig. 2, is made up of:

  • A microcontroller
  • Two non-contact temperature sensors

Fig 2 Sensors and battery connections on a wearable device. Source: MDPI

NodeMCU

It can manage jobs requiring a lot of computational power and low-power sensors. The ESP32-D0WDQ6 chip included in this module can be modified to satisfy certain needs. It has two CPU cores with 80–240 MHz frequency adjustments and a coprocessor that handles energy-saving functions, including peripheral control.

The module also provides possibilities for connecting to several peripherals, including:

MLX90614 Non-Contact Infrared Temperature sensor

The first temperature sensor is worn on the wrist, and the second one measures the forehead to gather data simultaneously from both. It has a:

  • A low-noise amplifier
  • A high-resolution 17-bit ADC
  • A DSP MLX90302

A 0.01 °C resolution of the computed object and ambient temperatures is provided. The manufacturer calibration ranges for the MLX90614 are broad: −40 to 125 °C for the ambient temperature and −70 to 382.2 °C for the object temperature.

Network Layer

Using the I2C communication protocol bus, the MLX90614 sensors and microcontroller NodeMCU work together to transmit information to the cloud via Wi-Fi using the MQTT (Message Queuing Telemetry Transport) protocol. 

The three main parts of the network are:

  • Tools
  • User profiles
  • Data accessibility

Tools

Examples of tools are:

  • Graphics cards
  • Memory
  • Other auxiliary connections that facilitate device configuration

User profiles

Two types of user profiles that exist are:

  • Viewers
  • Managers or administrators

Viewers have the ability to access the information using a PC or mobile device. In contrast, managers have the added capability to view the data and modify the data processing.

Data accessibility

Data accessibility governs communication, and the device uses Wi-Fi, Bluetooth, or ZigBee to connect with people or other devices.

Data Processing Layer

The processing layers are crucial in the IoT ecosystem. It serves as the central processing unit of an IoT system, where data is analyzed, pre-processed, and stored for future use.

Cloud Layer

The cloud storage layer is where data is managed and saved. It offers a flexible and expandable storage system suitable for handling data. Data availability, security, and accessibility for authorized users and applications are the responsibilities of the cloud storage layer.

Application Layer

This layer is essential because it allows the IoT system's components to connect, which is what transfers data from endpoint devices to central servers via the IoT pipeline.

A cloud platform called ThingSpeak was created especially for Industry 4.0 and IoT initiatives. It makes managing devices, data storage, and analysis easier. Users can import cloud data into ThingSpeak via an Application Programming Interface (API).

Security Layer

To protect IoT devices and their networks from numerous cyber threats, the Security Layer is a critical component of the IoT design. Since IoT devices come in a wide variety of forms, from basic sensors to intricate systems, it is crucial to secure them to preserve the reliability of the data they manage. Their functions include data encryption, authorization and authentication, and more.

To conclude, this study creates new ways to easily and accurately check body temperature. It also shows how important smart tech and advanced analytics are to the future of healthcare.

There are more topologies for monitoring bodily vital signs; these will be covered in later subsections.

Summarizing the Key Points

  • Wearable devices are revolutionizing healthcare by enabling remote vital sign monitoring and enhancing patient care.
  • The framework of a sensor-based wearable device typically consists of several layers that work together to gather, process, and transmit data effectively.
  • NodeMCU is the microcontroller that gathers sensor data, manages computational tasks, and facilitates communication with peripherals and sensors.
  • The non-contact temperature sensor, such as the MLX90614, is vital in wearable temperature measurements. It lets the device gather temperature data without physical contact, ensuring user comfort and convenience.

Reference

Mata-Romero, Marcela E., Omar A. Simental-Martínez, Héctor A. Guerrero-Osuna, Luis F. Luque-Vega, Emmanuel Lopez-Neri, Gerardo Ornelas-Vargas, Rodrigo Castañeda-Miranda, Ma. del Rosario Martínez-Blanco, Jesús Antonio Nava-Pintor, and Fabián García-Vázquez. “A Low-Cost Wearable Device to Estimate Body Temperature Based on Wrist Temperature.” Sensors 24, no. 6 (March 18, 2024): 1944. https://doi.org/10.3390/s24061944

Hayes, Adam. “What Is Wearable Technology (Wearables)? Definition and Examples.” Investopedia, July 11, 2022.
https://www.investopedia.com/terms/w/wearable-technology.asp