Blood Oxygen Level Monitoring System

Published on . Written by

Blood Oxygen Level Monitoring System
Today, most countries are struggling with the increased number of patients and increased costs of patient care per patient. This is happened because of an unhealthy lifestyle, habits, including stress which increasingly leads to chronic illness such as heart disease even in younger age. Also, it is difficult for doctors to monitor the particular patient for total working hours. In many critical conditions such as the patient is located far away from the hospital or also in case of an old patient who suffers from heart disease and physical disorders, continuous monitoring of the patient is not possible. Normally it is difficult to keep track of abnormalities in patient itself manually. Body temperature is 37 degree Celsius for a normal human being. Patients are not well with manual treatment which doctors normally used for tracking, so there must be a device which would help patient keep track of their health by themselves.

Read more..
Oxygen gas is necessary for human life. It is integral for countless biological processes. The transport of oxygen throughout the human body is performed by the circulatory system, and more specifically, hemoglobin in red blood cells. Critical medical information can be obtained by measuring the amount of oxygen in the blood, as a percentage of the maximum capacity. A pulse oximeter is a medical instrument that can detect heart-rate and oxygen saturation as signatures of our level of health condition. It can be implemented as a small device, and therefore, has been used widely in different applications.

Project Requirements:

  1. Temperature Sensor: LM35 used as temperature sensor which gives voltage variations for changes in the ambience temperature. The pin 2 which is output pin is connected at ADC0 pin of the microcontroller, while the pin 1 and 3 are Vcc and ground respectively.
  2. Thermistor: Thermistor 10K NTC 1% accuracy, Measuring range -20 to +105 degree Celsius, Cable Length 1 meter with 2.54mm pitch 2 pin JST connector. Here, one pin of the sensor is connected to the ground while other is connected to the PA1 (ADC1) pin of the microcontroller via a potential divider circuit.
  3. SPO2 Sensor: This sensor is useful in making Pulse oximetry, which is a test that measures what proportion of the oxygen-carrying molecules in the blood (called hemoglobin) are actually carrying oxygen. This is known as oxygen saturation or SpO2. It consists of IR and Red LED on one side and Light Detector on another side. A finger pulse oximeter is composed of two light emitting diodes (LED) for sensing blood volume and blood oxygen saturation in the finger.
  4. ATmega32 Microcontroller: The Atmel’s ATmega series microcontrollers are based on RISC architecture, which facilitates single cycle execution for most instructions. Also, the maximum allowed operating frequency of these controllers is 16MHz, thus allowing 16 million instructions execution in a single second @ 16MHz. It has two UARTs (Universal Asynchronous Receiver and Transmitter) hardware which makes it easier to interface it with the GSM modem.
  5. LCD Screen: The LCD screen shall be used to continuously display various status/error information in the GSM operation thus making us easy to debug the problems if any. Also, the LCD screen will display the actual real-time sensor data. We used 20x4 text LCD screen.
  6. GSM Module: GSM uses Time Division Multiple Access technology as their air interface standard. GSM uses Digital Communication System and is the world’s main 2G standard. GSM module is used for communication between the patient and a doctor.

Project Implementation:


    Skyfi Labs Projects
    The system we will be building is about a monitoring of vital parameters in a hospitalized person requiring constant measurement of his/her blood oxygen levels along with his/her body temperature. The system is built around an 8-bit µC ATmega32. It uses spo2 to measure blood oxygen levels in the patient in a non-evasive way, i.e., just by contacts and without any needles or blood samples. The room temperature is measured with the use of analog sensor LM35.

    The patient’s body temperature is being measured with the use of NTC thermistor of 10k value. The system displays the real-time values on the 20x4 LCD screen. The system is also capable of transmitting the measured values to a distance user by means of GSM communication on receiving the request from the user about the same. To achieve this, the system makes use of a separate communication module called SIM900 which is interfaced to the microcontroller at UART.

Kit required to develop Blood Oxygen Level Monitoring System:
Technologies you will learn by working on Blood Oxygen Level Monitoring System:


Any Questions?


Subscribe for more project ideas