AIRware

Files for the AIR project.

External Libraries

LiquidCrystal_I2C (https://github.com/fdebrabander/Arduino-LiquidCrystal-I2C-library/blob/master/LiquidCrystal_I2C.h)

How To Use

If the software is loaded as is onto the Arduino, and the:

• One button (black, on our design) cycles through age group settings
  • These can only be toggled while ventilation is not in progress
• Potentiometers adjust volume, pressure, and rate settings
  • These can be adjusted at any time
  • Volume measurements are calibrated as explained below
• If the airway is blocked, the servo will draw too much current and a blockage is predicted (see how to calibrate this below)

Volume Output Characterization

• Record volume outputs at various servo angles
• In scripts/volume_character.py, place these values into raw_vol and raw_ang
• Take the average volume output at each servo angle, place these values into vol and ang
• If any validation takes place, place these volumes and servo angles into val_vol and val_ang
• Note: the ang_to_vol function was determined by fitting a cubic to the volume output vs servo angle data in Excel

Blockage Detection Characterization

• Blockage detection is only implemented in adults right now
• Any adjustments to mechanical design requires recalibration
• To calibrate, output the volume, pressure, and current_sum value upon releasing the bag (around line 400 or so)
• Save this data in Excel in the format shown in current_data.xlsx, which contains the most recently-used data for characterization
• Run scripts/current_character.py to fit a surface function to the data and output the coefficients [a, b, c, d, e, f]
  • polynomial of the form z = a + bx + cx^2 + dy + ey^2 + fxy
• Apply these coefficients in predict_current() function