A spirometer is a lung capacity measurement device that is a primary indicator of airway or lung disease. Users (typically children) undergo routine assessments; however, adherence to tests is low and the tests, mind-numbing. Most commercial spirometers today require computers, and do not share designs or data collected.
We built a custom spirometer with an open data interface for analysis. Using an off-the-shelf laminar flow tube with a pressure sensor to measure the flow, the hardware connects to any bluetooth-enabled device to display the data. Some of the features of the 3in x 1.5in board are:
- A Texas Instruments MSP430F5437, with enough processing to run data filtering algorithms
- Interface to any pressure-based laminar flow tube
- Bluetooth connection to Android smartphones and tablets
- Run on two AA batteries for days of testing
- Custom Android API for data filtering and application design
- Auto-startup without the need for user configuration
- A switch and LED for the user interface
In addition to the custom PCB, I concurrently designed a 3D-printed case for the spirometer.