Implementation of a manually operated blood pressure monitor based on energy harvesting for use in resource-constrained settings

Health workers who screen for hypertension in rural and resource-constrained settings face many challenges including limited training, difficulties in correctly performing blood pressure (BP) measurements, and electrical grid unreliability. The aim of this study is to present the implementation of a manually operated BP monitor which assists health workers in overcoming some of these challenges by harvesting energy during manual cuff inflation and then discharging it in a controlled manner to power BP data acquisition, storage and wireless transmission. A prototype device was fabricated using a rotary alternator, flywheel and capacitor which harvests and stores energy when the bulb is squeezed during cuff inflation. Testing of the prototype revealed that an average of 1.55 J of energy can be scavenged during 30 s of cuff inflation. This is sufficient for BP data acquisition, storage and wireless transmission to a near-by smartphone even when accounting for losses.