Even though this week was short because of the Fourth of July, we made a lot of progress! We consolidated our circuit for the blood pressure monitor onto one bread board, which was more challenging than we anticipated. We spent all of Monday and part of Tuesday troubleshooting, only to find that one of our parts (the current amplifier) was faulty.

Once we finally fixed it, we could move along. We were able to install five LEDs that light up based on the pressure. For example, pressures that are unhealthily low, the blue LED is lit. The red LED lights up when the pressure is extremely high. Here are our LEDs:

 

At the end of the week, we were able to install a cuff and a manual pump that allows us to actually take blood pressure. However, since we don’t yet have a way for the arduino to know when to take a pressure reading (based on Korotkoff sounds), at this point it is still up to the user to listen to the pulse sounds. At appropriate Korotkoff sounds, the user can look at the LCD or the LEDs to see the numerical pressure value as well as its severity.

This week, our goal is to integrate the pulse sensor into our design and begin testing. We don’t have the sensor yet, but once it arrives, we will be able to use it to listen to Korotkoff sounds and thus tell the arduino when to take pressure readings. By the end of the week, we should have a working prototype that we can begin testing (by comparing the readings our device gives to the readings of a mercury sphygmomanometer).