Blood Pressure Sensing from a Smart Phone

Was involved in defense department look at how to do inobtrusive, non mechanical blood pressure sensng.   Was considered impossible at one time.   The method described does not require complex calibration. Availability not mentioned. Includes video.

New Smartphone Sensor Checks Your Blood Pressure
It’s more convenient than a cuff   and could help patients monitor hypertension at home
By Emily Waltz in IEEE Spectrum

For years, scores of engineers have been trying to develop a more unobtrusive, convenient device for blood pressure monitoring. Now, researchers at Michigan State University and University of Maryland appear to have succeeded.

In a paper published today in Science Translational Medicine, the researchers described a prototype blood pressure sensor that can be incorporated into a smartphone, and requires only the press of a fingertip.  

The convenient device could encourage people to check their blood pressure more often, allowing them to catch hypertension—persistently high blood pressure—sooner, says Ramakrishna Mukkamala, a biomedical engineer at Michigan State, in East Lansing, who led the study.   ... "