FYP2 : Week 3

Sensor changes

Objective : 

• To replace sensor to be use for the project

• To ensure which sensor suitable to be as replacement

Activity: I had already tried survey market price for photoplethysmographic (PPG) sensor which this sensor is to detect the blood pressure reading. However, none of this sensor sold in Malaysia.  Its only available at overseas market. Besides, the price for the sensor is 75$ which cost RM 311.70 as shown in figure 1.This sensor price is expensive and not affordable for a student and also for user under B40 group. So, this sensor need to be change to other sensor that might produce almost similar function.

Figure 1 PPG sensor's price

The most common sensor been used in other medical projects to detect vital reading is pulse sensor. This sensor can detect heart rate reading from the blood circulation. The sensor is available on Malaysia's market and the price of this sensor is only RM 20.90. Moreover, the coding of the pulse sensor have a lot of open source coding for it which can be refer in making this project. It also have official website for the sensor which is https://pulsesensor.com/ .  The size of this sensor is small which is only around 16mm of diameter with thickness only 3mm which make it suitable for this project as this project need to be in a compact size as it is a wearable device. It support voltage from 3V to 5V which same with others component in this project. Here I attached the datasheet of the pulse sensor : Datasheet Pulse Sensor  

Figure 2 Pulse sensor

Conclusion : The PPG sensor which to measure the blood pressure changed to pulse sensor as it easier to get in market and the price is more affordable. However, pulse sensor is to detect the heart rate of the user. As this project is focusing on blood pressure abnormality, the relationship between heart rate and blood pressure need to be study.