Progress Report, Week 8: March 28th

On Monday, we picked up the prototype that was left in Dr. Liu's lab. The exterior of the jar has solidified and does not appear "sticky" anymore; however, the interior still had areas of "stickiness". This has since disappeared as we have worked on the device throughout the week.

During Monday's lecture, discussion of testing has led us to believe that our current amplification system may not be enough to see our visual indicator. We have chosen to mimic the current stethoscope chestpiece design and add a cone to more specifically redirect the pressure. Our understanding of how amplification works in a stethoscope suggests that there will be better transmission and amplification in the chamber with this design, as opposed to open space between the lower and upper membrane. Our desired material is aluminum from a typical soda can. During Friday's lab time, we determined the geometry and shape that we must have in order to create the desired shape and dimensions of our device. 

Additionally, on Friday, we did further research into this conical design and planned to test the device, but did not have a readily available soda can. Instead, we fabricated a cone out of paper to better understand the manufacturing of the cone. Furthermore, we have resumed examination of the arduino code. The implementation of the millis() function before and after the bulk of the evaluating code has given us this table (truncated for simplicity):

Notably, the difference between counts (the last column) is not equivalent to our desired value of 100ms. We will decide next week whether we would like to use this new value to change our delay in the code, or if we should use the difference between the Time1 and Time2 values to determine non-uniform sampling.

Jibril Ashiru-Balogun and Ada Tsoi