A domestic research team has developed a wireless electronic patch that can measure blood flow in real time simply by sticking it to the skin.
Professor Kwon Kyung-ha's team in the School of Electrical Engineering at KAIST said on the 5th that it developed a wireless wearable blood-flow measurement system that combines Deep Learning and multilayer thermal sensing technology. The research findings were published in the international journal "Science Advances" in February.
Until now, blood flow has been measured using ultrasound or optical methods. However, there were limitations such as bulky equipment or reduced accuracy depending on vessel depth.
Noting that minute heat transfer occurs around flowing blood, the team developed a multilayer thermal sensing technology that places temperature sensors at different depths to three-dimensionally analyze heat transfer paths. By applying an artificial intelligence (AI) algorithm, it separated and extracted in real time the vessel depth and actual blood-flow speed from complex body-temperature distributions.
In experiments, the team succeeded in measuring blood-flow speeds in the 1–10 mm per second range with an error within 0.12 mm/s, and vessel depths in the 1–2 mm range with an error within 0.07 mm. This margin of error is smaller than the thickness of a human hair and is a level of precision difficult to achieve with typical wearable devices.
In particular, when this technology is combined with a photoplethysmography (PPG) sensor used in smartwatches, it was shown to reduce blood-pressure measurement errors by up to 72.6%.
This electronic patch can be used in emergency medical settings to detect changes in a patient's condition in real time. It can also be applied to personalized health management for patients with hypertension or diabetes and to the early detection of acute risk signals such as shock.
Professor Kwon Kyung-ha said, "This technology is a fundamental platform that can measure blood flow and blood pressure more accurately," adding, "When combined with a smartwatch, it will raise the level of everyday health monitoring by a notch."
References
Science Advances (2026), DOI: https://doi.org/10.1126/sciadv.aea8902