Title:  Unobtrusive Blood Pressure Monitoring using Pulse Transit Time: Scale and Wearable Based Approaches

Committee: 

Dr. Inan, Advisor

Dr. Wang, Chair

Dr. Butera

Abstract:

The objective of the proposed research is to develop unobtrusive sensing techniques for monitoring pulse transit time to estimate blood pressure. Developing such techniques is imperative to providing an at-home solution that is more convenient than current monitoring systems, such as an oscillometry cuff. First, a scale-based approach utilizes full-body vibrations, called the ballistocardiogram, to provide a measurement of the pulse at a proximal location to the heart. By attaching a custom-made optical sensor on the foot and thus measuring a distal pulse timing, the scale-based approach captures true aortic pulse transit time and provides a superior estimation compared to conventional timing based methods. Second, a watch-based sensor, SeismoWatch, allows the user to sense pulse timings at the chest and the wrist. SeismoWatch is non-invasive, unobtrusive, and compact, allowing for convenient and portable blood pressure tracking. As part of the proposed works, calibration methods will be explored for both the scale and SeismoWatch. Moreover, the distal timing reference will be further improved to allow users to simply stand on the scale to obtain ideal measurements. Lastly, features from both the scale and SeismoWatch data will be analyzed using machine learning algorithms to improve blood pressure estimations.