Pulse Wave Blood Pressure Estimation Corrected for Vessel Size
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for estimating cardiovascular characteristics like blood pressure without a cuff, such as pulse wave analysis (PWA) and pulse wave velocity (PWV), face inaccuracies due to variations in blood vessel size and contact pressure, leading to errors in estimation.
Innovation Solution
An apparatus and method using a first sensor to measure pulse wave signals of different wavelengths and a second sensor to measure force/pressure, generating an oscillometric waveform envelope, predicting blood vessel size, and correcting feature values to estimate bio-information like blood pressure, using a bio-information estimation model.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If pulse wave analysis or pulse wave velocity methods are used to estimate blood pressure without a cuff, then the ease of operation is improved, but the measurement precision deteriorates due to variations in blood vessel size and contact pressure
Solution Approach 1:
The patent applies parameter changes by using multiple wavelengths (first and second wavelengths) for pulse wave signals and incorporating force/pressure measurements to dynamically adjust and correct the oscillometric waveform envelope, thereby compensating for variations in blood vessel size and contact pressure to improve measurement precision
Solution Approach 2:
The patent implements feedback by using the second pulse wave signal and force/pressure measurements to predict blood vessel size, then correcting the feature values extracted from the oscillometric waveform envelope based on this predicted size, creating a closed-loop system that improves measurement accuracy
2Measurement precision
If oscillometric waveform envelope is generated and corrected based on multiple parameters, then the measurement precision is improved, but the device complexity increases
Solution Approach 1:
The patent applies universality by using the first sensor to measure both first and second pulse wave signals at different wavelengths, and by having the processor perform multiple functions including generating the oscillometric waveform envelope, extracting feature values, predicting blood vessel size, and correcting measurements, thereby reducing device complexity through multi-functional components
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
Improves accuracy in estimating bio-information by accounting for variations in blood vessel size and contact pressure, providing precise measurements of blood pressure and other cardiovascular characteristics.
Implementation Method 1
a first sensor configured to measure a first pulse wave signal of a first wavelength and a second pulse wave signal of a second wavelength from an object
Data Source
AI summary
An apparatus for estimating bio-information is provided. According to an embodiment of the present disclosure, the apparatus for estimating bio-information includes: a first sensor configured to measure a first pulse wave signal of a first wavelength and a second pulse wave signal of a second wavelength from an object; a second sensor configured to measure at least one of a force or a pressure applied to the object; and a processor configured to: generate an oscillometric waveform envelope based on the first pulse wave signal of the first wavelength and the at least one of the force or the pressure applied to the object; obtain a feature value from the oscillometric waveform envelope; predict a size of a measured blood vessel based on the second pulse wave signal of the second wavelength; correct the feature value based on the size of the measured blood vessel; and estimate the bio-information based on correcting the feature value.