DESIGN AND DEVELOPMENT OF IOT BASED HEALTHCARE MONITORING SYSTEM DESIGN AND DEVELOPMENT OF IOT BASED HEALTHCARE MONITORING SYSTEM HO CHI MINH CITY UNIVERSITY OF TECHNOLOGY AND EDUCATION
INTRODUCTION
The Role of the Research
The rapid advancement of technology has made smart healthcare gadgets familiar to many, enabling continuous collection and analysis of health data These devices empower individuals to monitor key health indicators and receive alerts about potential issues before they escalate, significantly enhancing illness prevention and early detection.
Monitoring medication is crucial for elderly individuals who often need prescriptions for managing health conditions Smart devices can help seniors keep track of their medication schedules, ensuring they take the right doses at the right times, which prevents forgetfulness and misuse.
In emergencies like falls or sudden health issues, smart devices play a vital role by sending immediate alerts This feature is particularly important for the elderly, who may face memory challenges that can lead to getting lost or forgetting how to return home Such capabilities can be life-saving in dangerous situations.
The Role of the Research Topic for Science and Practice
Understanding electronics and programming is essential for developing health monitoring systems tailored to the elderly Combining these disciplines fosters innovative engineering solutions that address the unique needs of older adults A thorough analysis of design thinking, weight, size, and safety considerations is crucial to identify the requirements and limitations faced by seniors, ultimately ensuring their safety and convenience in health monitoring.
This research project focuses on the importance of monitoring the health of elderly individuals, offering significant practical benefits The monitoring device aids families in supporting their elderly relatives by overcoming various challenges and obstacles related to health management.
The project's innovative goods and technology have the potential to enhance health management systems, ensuring secure and reliable tracking of senior citizens' health conditions The study's findings address the challenges faced by families and caregivers, promoting more efficient methods to safeguard the well-being of the elderly population While the research has its limitations, it offers valuable insights that could lead to practical solutions for families and communities dealing with elder healthcare monitoring.
Objectives
Creating a system for monitoring the health of the elderly requires:
• Health monitoring: monitor heart rate and blood oxygen levels
• Falling detection: set up an automated monitoring system that automatically sends out emergency calls and messages on itself when it falls
• Track location: locate your location and use a push button to send emergency calls and messages in case getting lost
• Event reminder: set notifications for exercise, medicine, and drinking water events.
Research scope and value
This research targets individuals aged sixty and older, emphasizing the importance of understanding their specific needs to effectively develop a device tailored for them The study will also explore additional metrics to formulate algorithms that enhance accuracy A key priority will be to ensure precise and timely monitoring of vital signs such as heart rate and oxygen levels.
The group's main goal will be to create a little gadget with optimal proportions for user comfort To guarantee the best possible affordability, a comprehensive cost study will also be conducted
To enhance device usage duration and minimize user frustrations with battery charging, it is essential to optimize the power supply to meet device requirements Key to this process is the careful adjustment and monitoring of parameters, which will help reduce measurement errors and ensure accurate tracking.
To effectively study and evaluate appropriate resources for research, it is essential to analyze various documents, reports, books, past studies, and online data This comprehensive review aids in gaining a deeper understanding of the research field, its pertinent issues, and the proposed solutions.
To gather information about parameters, technical standards, requirements, and potential health issues may encounter, conduct surveys or investigations.
Format of the project
Chapter 2: Synopsis of the project’s study
Chapter 3: Attributes and Components of the system
SYNOPSIS OF PROJECT’S STUDY
Methodology of monitoring
An essential measure of the state of health is heart rate We have many ways of measuring heart rate, each with positive and negative aspects
Figure 2.1 The standard heart rate monitor
Measuring heart rate manually is a straightforward and safe method, allowing individuals to feel the pulse with their fingers However, this technique may lack accuracy, as the perception of the pulse can vary among different individuals.
Figure 2.2 The electronic heart rate monitor
Electronic heart rate monitors utilize sensors to accurately measure heartbeats, offering greater precision than traditional manual methods While this technology enhances measurement accuracy, it necessitates medical equipment and may present challenges for the individual being monitored.
Optical heart rate measurement utilizes optical light to assess changes in heart rate through the skin, allowing for continuous monitoring However, this method may not provide the same level of precision as electronic heart rate measurement techniques.
To measure heart rate using a smartphone application, users can easily follow a straightforward method that requires only their device While this approach is convenient and user-friendly, it is important to note that it generally offers lower accuracy compared to other heart rate measurement techniques.
Users can choose the best heart rate measurement method based on their needs For a quick and accessible option, heart rate can be measured using a phone application or optical measurement However, if high accuracy is required for multiple readings, the manual measuring method is recommended.
The body uses blood oxygen concentration (SpO2) as a key signal to determine how well the blood is oxygenated Adults have a SpO2 index between 95% and 100%
Monitoring your SpO2 levels is crucial, as deviations from the normal range may indicate potential health issues, including heart or respiratory problems, necessitating prompt medical attention SpO2 can be assessed through various methods, primarily categorized into intrusive and non-invasive techniques.
Figure 2.3 The oxygen in the blood
Venous blood sampling using a needle is an invasive method for measuring SpO2 levels This technique allows for precise analysis of the oxygen content in the blood sample, providing high accuracy in results However, it is important to note that this approach can be uncomfortable for the patient.
In essence, pulse oximetry is a non-invasive, painless technique for determining a person's blood oxygen saturation level
Oxygen saturation is a key indicator of lung function, as it measures how effectively the lungs transfer oxygen from inhaled air into capillaries These tiny blood vessels then carry oxygen-rich blood to the heart, which pumps it throughout the body via arteries.
2.1.3 MAX30100 (Heart Rate and Blood Oxygen Concentration Sensor)
The MAX30100 sensor measures blood oxygen concentration (SpO2) and pulse rate using two optical LEDs to absorb light Its low noise and stable signal processing ensure consistent accuracy and long-lasting durability in monitoring heart rate and SpO2 levels.
The MAX30100 sensor consists of a light emitter and a photodetector, utilizing LED lights to absorb and emit red light For accurate readings, the LED must be placed on or near the skin, where blood vessels are accessible The photodetector measures light transmission to calculate oxygen concentration (SpO2) and heart rate, transmitting the data to the sensor's control center for processing.
There is a maximum error of ±1 to ±5 beats per minute between 30-
200 beats per minute and the real value, PW 200às, 50sps
70%–100% accuracy with ±2% error SpO2 does not vary by more than ±2% PW = 200às, 50sps in reality
INT Non-active at low level (logic 0)
2.1.4 Accelerometer Sensor GY-521 with 6 Degrees of Freedom IMU MPU6050
The GY-521 6DOF IMU MPU6050 speed sensor is an essential tool for real-time applications, offering valuable data on speed and angular rotation This compact device integrates a three-axis accelerometer with a three-axis gyroscope, providing comprehensive motion tracking capabilities.
The MPU6050 is a six-degree-of-freedom sensor designed to track an object's rotation angles and velocity in three-dimensional space It combines a gyroscope and an accelerometer within a single chip, making it an essential component for various applications in motion detection and orientation sensing.
X, Y, and Z are the three axes along which the MPU6050 can monitor acceleration It offers details on variations in the object's speed
The MPU6050 features a 3-axis gyroscope that accurately measures roll, pitch, and yaw angles, allowing it to detect changes in an object's rotation Alongside its accelerometer, this sensor effectively tracks rotational movements, making it a vital component for various applications.
I2C communication standard: The MPU6050 communicates with other devices, like microcontrollers or computers, by using the I2C communication protocol to send data regarding rotation angles and acceleration
Table 2.3: GY-521 6DOF IMU MPU6050’s Characteristics
Table 2.4: Ports of GY-521 6DOF IMU MPU6050
INT Non-active at low level (logic 0)
The GY-NEO 6M V2 GPS positioning module leverages the US GPS satellite system for accurate global positioning Designed with multiple power settings, it is ideal for battery-operated applications, delivering fast and precise location determination.
• The principal for GPS NEO 6M-V2 operation:
The U-blox NEO-6M GPS chip, measuring less than a postage stamp, offers impressive capabilities, including tracking up to 22 satellites across 50 channels with a sensitivity of -161 dB while consuming only 45 mA of current It can deliver 5 location updates per second with a horizontal accuracy of 2.5 meters and features a Time-To-First-Fix (TTFF) of under 1 second Notably, the chip includes a Power Save Mode (PSM) that significantly lowers power consumption to just 11 mA, making it ideal for power-sensitive devices like GPS wristwatches The NEO-6M's data pins are conveniently arranged in 0.1” pitch headers, allowing for easy communication with microcontrollers via UART, supporting baud rates from 4800 bps to 230400 bps, with a default setting of 9600 bps.
Figure 2.6 The GPS NEO 6M-V2 sensor
There are several applications for the GPS sensor NEO 6M-V2, including:
- GPS Positioning: the GPS sensor NEO 6M-V2 locates unidentified devices vehicles (UAVs), tablets, smartphones, and other devices
Significations
Heart rate monitors, smart wristbands, and smartwatches are popular health-tracking devices that allow users to monitor their heart rate in real time These devices collect heart rate data and automatically upload it to cloud storage services, where it can be accessed through a smartphone app for easy viewing.
You can monitor your heart rate as needed with this tool When you believe it is necessary, you can use it to monitor your heart rate
SpO2, or blood oxygen levels, is a crucial health indicator that measures the amount of oxygen in your bloodstream Low SpO2 levels can indicate potential health issues, including infections or diseases affecting the heart or lungs.
Monitoring blood oxygen levels is a key feature of health evaluation devices like pulse oximeters, smart wristbands, and smartwatches, akin to heart rate monitoring This capability allows users to track their blood oxygen levels in real-time After collecting the SpO2 measurements, the device promptly sends the data to cloud storage, which can then be accessed through a smartphone app for easy viewing.
Automated fall detection is an essential feature of health monitoring devices, especially for elderly individuals or those at high risk of falls This technology enhances safety by promptly detecting falls and alerting users, significantly reducing the likelihood of accidents that could result in severe injuries or fatalities.
The automatic fall detection feature utilizes sensors such as accelerometers to monitor user movements These sensors detect sudden changes in motion, including abrupt shifts in direction or speed, which indicate a fall.
The automatic fall detection feature alerts users or selected contacts when a fall is detected, initiating an emergency call to designated contacts and providing the user's location data.
Location tracking is an essential feature of health monitoring devices for individuals who want to keep tabs on their activities or seek assistance during emergencies This capability allows for real-time tracking of the user's location, enhancing safety and support.
In case of getting lost, individuals can use the emergency button on their mobile app to alert loved ones about their location and initiate an emergency call This app enables family members to utilize GPS technology to navigate to the specified location upon receiving the alert.
Fall location tracking enables users to quickly alert their loved ones by sending a message with their location and an emergency call when they are lost The mobile app utilizes GPS technology, allowing family members to navigate to the specified location upon receiving the alert.
This tool enables users to create calendar reminders that encompass essential details like date, time, and location, making it easier for family members to monitor seniors' schedules and important events Family members can set up reminders for various activities, including workout routines, medication timings, and medical appointments Additionally, the application sends automatic notifications to family members' phones as these scheduled events approach, ensuring they stay informed and engaged.
Analyze the system’s architecture
The hardware device serves as the foundational component of the system overview, responsible for data gathering and control processing To continuously display the collected data, a mobile app is utilized, while database storage services are essential for retrieving values from the hardware The team chose cloud data storage services for their reliability and ease of use.
• The SIM Module block: facilitates the sending and receiving of SMS, in addition to phone calls and GPRS data transfer
• Central Processing Block: This unit powers the remaining components, including the sensor unit It gathers and analyzes the sensor units' signals
• Location block: Using longitude and latitude data, this unit provides and pinpoints the location of the monitored object The central processing unit receives these values
• Central Processing Block: This unit powers the remaining components, including the sensor unit It gathers and analyzes the sensor units' signals
• User Interaction block: When a button is pressed, this device sends forth signals
• Power Supply block: This component powers the SIM module and the central processing unit
In this segment, we will connect 2 sensors, including:
- Sensor for Monitoring Blood Oxygen and Pulse: This sensor keeps track of blood oxygen and pulse data Additionally, it gives the central processing unit access to the measured values
- Intelligent Fall Detection Senor: The sensor supplies acceleration and angular velocity data to the central processing unit It autonomously detects falls by analyzing acceleration and angular velocity parameters
Firebase, developed by Google, is a leading platform for building mobile and web applications, providing essential tools and features for effective app development and management.
In this project, our team will utilize Firebase's real-time database to store measured values and user registration data We will also implement Firebase's authentication service to verify users during the account registration process.
With the widespread accessibility of mobile phones, families often prefer to monitor health-related statistics through an app instead of a web interface Consequently, the team has decided to present user-related information through a mobile application, which is developed using the Android operating system.
Essential features of the app will include user registration for new users and the presentation of pertinent user data.
Analyze and Design
My team selected the Accelerometer Sensor GY-521 with 6 Degrees of Freedom IMU MPU6050 and the MAX30100 pulse and blood oxygen sensor based on the project requirements
The operating voltage for both the MAX30100 and MPU6050 sensors is 3.3V The MAX30100 sensor has a current consumption of 0.0007 mA, while the MPU6050 sensor consumes 3.9 mA By summing the individual current consumptions of the MPU6050 (IMPU6050) and MAX30100 (IMAX30100), we can calculate the total current consumption of the sensors (ICB).
Figure 3.4 MAX30100 connect to MPU6050
The NEO 6M-V2 GPS module utilizes the UART interface to enable seamless data communication with the ESP32 This interface simplifies the data transmission process between the two devices To connect the NEO 6M-V2 GPS module to the ESP32 via the UART interface, specific pin configurations must be established.
- NEO 6M-V2 TX (Transmit) -> ESP32 RX (Receive)
- NEO 6M-V2 RX (Receive) -> ESP32 TX (Transmit)
- NEO 6M-V2 VCC (Power) -> ESP32 3.3V or 5V (depending on module voltage requirement)
- NEO 6M-V2 GND (Ground) -> ESP32 GND (Ground)
GPS NEO 6M-V2 runs at a voltage of 5V The schematic diagram that follows shows how the pins on the ESP32 and the GPS NEO 6M-V2 are connected
Figure 3.5 GPS NEO 6M-V2 connected to ESP32
The SIM800L module, connected to the ESP32's UART port, requires a 5V operating voltage and a current of 1 to 2A, which exceeds the ESP32's maximum output To ensure proper functionality of the SIM module, it is essential to use a power supply sourced from an LM2596 voltage regulator module.
Figure 3.6 Module SIM800L connected to ESP32
The system uses a text message to communicate coordinates and features a push button linked to the ESP32 for user notifications When the button is pressed, the pin reads a value of 1 (HIGH logic) due to its connection to VCC and GND via a 10kΩ resistor Conversely, when the button is not pressed, the pin connected to GND through a 10kΩ resistor registers a value of 0 (LOW logic).
Figure 3.7 The button segment and connected to ESP32
The component features multiple operational modules, primarily powered by a 5V supply It processes signals from various sensors and transmits data across modules using I2C and UART communication standards We have selected the Moule ESP32 Mini Wemos D1 WiFi Bluetooth as the core processor due to its compact size, which meets all specifications, and its ample interface capabilities, providing 31 digital I/O pins and 1 analog I/O pin for simultaneous communication with multiple modules.
To ensure reliable and portable power for the gadget, it requires a dependable off-grid energy source A 3.7V Lipo battery meets these needs due to its long lifespan, energy efficiency in standby mode, and compact size, making it ideal for mobile devices Consequently, the team has opted to utilize two 3.7V Lipo batteries to effectively power the gadget.
To design an effective power block for a circuit, it is essential to consider the voltage and current requirements of each component By understanding the current consumption of individual components, we can calculate the total current needed for the circuit to operate efficiently This involves summing the current usage of all components to ensure the power block provides adequate voltage and current for optimal functionality.
Table 3.1: The voltage and current consumption of all components in the system
The team opted for a power source consisting of two 3.7V LiPo batteries in series, yielding a total voltage of 7.4V, based on collected data To regulate this voltage, an LM2596 voltage regulator is employed to reduce it to 5V, with a maximum current output of 3A Each battery offers a capacity of 2500mAh, and with the total current consumption for all devices estimated at around 750mA, the team calculated the expected device usage time accordingly.
Consumption Time = Battery Capacity (mAh) / Current Consumption (mA)
Consumption Time = 2500mAh / 750mA ≈ 3.3 hours
It has been noted that the battery can run the gadget for more than three hours
As a result, the group has chosen to power the circuit using two 3.7V Lipo batteries connected in series.
Full systems’s schematic
Following the design, computation, and integration of each system block into a unified whole, the system's overall schematic diagram can be summed up as follows:
Workflow Diagram
Figure 3.10 The flow of the system’s operation
The system comprises multiple subprograms designed to fulfill specific functionalities based on defined specifications These applications enable users to register customer information via an app, monitor vital signs like blood pressure and pulse, determine their location, detect falls, provide directions if they become lost, and send reminders for upcoming events.
3.5.2 Flow of programming to upload data
Figure 3.11 The flow of uploading data
To access the app for the first time, users must create an account by providing personal details and information about the elderly individual being monitored Once the necessary information is submitted, the system checks Firebase's real-time database to verify if the user's phone number is registered If the number is not registered, an OTP code is sent to the user's phone via Firebase's authentication service, leading to the OTP verification screen After successful login, the provided information is securely stored in Firebase's real-time database for future reference.
3.5.3 Flow of oxygen and heart rate metering
Figure 3.12 The flow of oxygen and heart rate metering program
The sensor measures pulse and blood oxygen levels by making contact with a fingertip, subsequently transmitting the data to the ESP32 for analysis Once the measurement is complete, the system checks for internet connectivity If connected, the pulse rate and blood oxygen values are uploaded to Firebase for storage, enabling users to view this information in real-time through the software.
3.5.4 Flow of program located by app
Figure 3.13 The flow of the program located by app
The GPS positioning script functions like blood oxygen and pulse measurement programs by automatically connecting and collecting location data, including latitude and longitude, upon device activation This data is processed by the ESP32 and then transmitted to Firebase, allowing users to track their location through Google Maps using the gathered information.
3.5.5 Flow of fall detection program
Figure 3.14 The flow of the fall detection program
The software will read the acceleration angles along the Ox and Oy axes, performing this reading and conversion process every two seconds for early fall detection The ESP32 processor unit will calculate the angular values for both axes by analyzing the acceleration data collected.
When computing values exceed the specified threshold, the system alerts the registered phone number with a warning message that includes the incident location Upon clicking the link in the message, the app will automatically open and provide directions to assist the family member in distress.
3.5.6 Flow of locating missing cases
Figure 3.15 The flow of locating missing cases
When the user presses the designated button on the device, it signals that they are lost The ESP32 promptly detects this signal and triggers an SMS phone call, sending a notification that includes the current map coordinates—latitude and longitude By clicking on this notification, users can access the app, which provides directions to their lost location.
3.5.7 Flow of calendar reminds program
Figure 3.16 The flow of calendar reminder program
IMPLEMENTATION AND EVALUATION
Overview
The PCB circuit model was successfully deployed and verified following the completion of the calculation and design phases We constructed, packaged, and tested the circuit to ensure optimal performance Ultimately, the development of the PCB circuit significantly improves the stability of the circuit's architecture.
Implementation
Before constructing the PCB, we need to prepare the equipment and tools:
- Using Proteus to draw and export the circuit as file PDF
- Cutting copper board to fit the size of the printed
- Place the printed image down onto the side of copper board
- Using the ink to iron and applying on copper board
- Getting the board into water for 1 to 2 minutes, then peel that paper
- Soaking the board until the unprotected copper areas are completely corroded
- Rinsing the board with water
- Using solder to prevent the copper from oxidation
- Checking for circuit continuity by using multimeter
- Drilling holes and get all components attached to the board
When we implement the circuit, designing the wiring illustration is essential The following steps shows the printed diagram
Figure 4.1 Circuit illustration drawn using Proteus
Creating a component layout diagram is crucial for visualizing the arrangement of components in a project At the center of the diagram is the ESP32, with the LM2596 voltage regulator positioned in the upper right corner and the SIM800L module located in the lower right Adjacent to the SIM800L are the Max30100 sensor and the MPU6050 Additionally, the buzzer, switch, resistor, and terminal are placed next to the ESP32, ensuring a clear and organized layout for effective project implementation.
After obtaining the display diagram and do all the checks up, we can print the PCB design with dimensions of 10.5 x 8
Figure 4.3 PDF file of the circuit
To ensure user-friendly and visually appealing equipment that is protected from external impacts for safe operation, we will finalize the implementation The component box will be designed using 3D printing technology to create a durable case for the device.
Figure 4.5 The shell to protect
Outcome product and evaluation
The group has established a registered account and password for users to access the mobile application User personal information is securely stored in Firebase, allowing for a safe login experience through the provided account credentials.
4.3.1.2 Blood oxygen and heart rate function
The Max30100 sensor, conveniently located at the center of the device, allows users to comfortably measure their blood oxygen levels and heart rate By placing their finger on the sensor, the LED activates to scan the finger, providing accurate readings of blood oxygen concentration and heart rate.
Figure 4.7 Check oxygen and heart rate using finger
After measuring, the value will be uploaded into firebase and appear in application on device
The group decided to use Open Street Map because of the easy and user-friendly interface to located user’s position
• When the user gets lost
The device features an integrated button that allows users to send emergency calls and messages to a pre-registered phone number By pressing this button, the accompanying application can also obtain the user's location for immediate assistance.
Figure 4.10 Message and calls for emergency situation
By clicking the provided link, users can access their current location, activating the map feature that enables navigation to help them find their way when lost.
In emergency situations, calls and messages will include the user's location at the time of a fall This location data is obtained using the MPU6050 sensor, which measures motion and orientation, and is compared against a predefined threshold to detect falls accurately.
Figure 4.11 Message and calls for falling
By clicking the link, users can access their location, activating the map feature and enabling navigation to their current destination.
When click into the reminder feature, we have an interface calendar containing 3 options contain exercise event, medication event and examination event as shown below
To set up reminders for events, users need to input the date, time, event name, and a description After successfully adding an event, the application will notify them at the designated time and date.
- Gathering blood oxygen and heart rate value then show on the application
- Using GPS to obtain the location and show on the application
- Sending messages and emergency calls to the numbers registered when problems happened for instance falling or getting lost
- Creating notifications when adding events like exercise, medicine, and examination
The implementation, afterward, the group has reached the goals and conditions
- The project uses and operates easily
- The completed shell is tough and high stable
- The cost is low for the project
- Used in various locations and features a rechargeable battery
- The interface is user-friendly and intuitive
- Hard to get the location because GPS is unstable in narrow or indoor space, unable for antenna signal acquisition
- The accuracy of heart rate and blood oxygen is not high because of the quality of the sensor and contact position as the method relies on optical light absorption
- Need a quality 3G or wifi for the system
The system is designed to help monitor health indicators Additionally, its size and usage time are improved for convenience.
CONCLUSION
Conclusion
Our research team, in collaboration with Associate Professor Ph.D Phan Van Ca, has successfully achieved the project goals through extensive study and analysis.
- The product fulfills the conditions about controlling and monitoring of the status of devices
- Data obtained by sensors are show on the application
- A warning notification for users by application, buzzer, messages and calls
Time and knowledge constraints lead to several disadvantages for devices, such as limited data availability, weak signal strength in certain areas, an unappealing user interface, and delays in data transmission and reception.
Improvement
The team will try to enhance functions along with getting pass the current shortages of the project, improving system to increase accuracy and practicality
Our goal is to minimize the timer's system delay while enhancing user experience We are implementing an additional navigation feature within the app to streamline the storage and retrieval of test results, making it easier for family members and doctors to access important information.
Our system is designed to operate in two modes: an active mode for full functionality and an idle mode for energy conservation This dual-mode approach aims to maximize energy savings while ensuring the system remains operational 24 hours a day.
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