Physiologic-range flow and pressure sensor for respiratory systems

• Main Authors: Lui Holder-Pearson, J. Geoffrey Chase
• Format: Article
• Language: English
• Published: Elsevier 2021-10-01
• Series: HardwareX
• Subjects: Respiratory analysis; Reusable sensor; Mechanical ventilation; Customisable sensor
• Online Access: http://www.sciencedirect.com/science/article/pii/S2468067221000560

A low-cost but reliable flow and pressure sensor is an impediment to development of medical equipment, and studies of human respiratory function, which is characterised by relatively low pressures and flows. A Venturi tube (D1=15mm,D2=10mm) connected to a differential pressure sensor (SDP816-125 Pa) allows accurate measurement of flow between 5-75L·min-1, with Pearson Correlation over 4 min at 50Hz ⩾0.97, and distance correlation ⩾0.96. The pressure measurement was similarly accurate using a MPVZ4006GW7U. Both sensors provide an analogue output from a 5.0V supply, aiding compatibility and customisation. Each populated PCB costs approximately $50USD, and each Venturi sensor costs approximately $1USD. Multiple configurations exist, allowing flow rates up to 250L·min-1, increased resolution for specific ranges, and different physical characteristics.