A device, method and system for calculating, estimating, or monitoring the blood pressure of a subject. A first signal representing heart activity of a subject may be received. A plurality of second signals representing time-varying information on at least one pulse wave of the subject may be received from a plurality of body locations of the subject. A first feature of the first signal may be identified. For each of the plurality of second signals, a second feature may be identified. A pulse transit time based on a difference of the first feature and at least one of the second features may be computed. A blood pressure of the subject may be calculated according to a model based on the computed pulse transit time. The model may include a compensation term relating to the plurality of second signals or the second features thereof.

A system for non-invasively determining an indication of an individual's blood pressure is described. In certain embodiments, the system calculates pulse wave transit time using two acoustic sensors. The system can include a first acoustic sensor configured to monitor heart sounds of the patient corresponding to ventricular systole and diastole and a second acoustic sensor configured to monitor arterial pulse sounds at an arterial location remote from the heart. The system can advantageously calculate a arterial pulse wave transit time (PWTT) that does not include the pre-ejection period time delay. In certain embodiments, the system further includes a processor that calculates the arterial PWTT obtained from the acoustic sensors. The system can use this arterial PWTT to determine whether to trigger an occlusive cuff measurement.

A blood pressure measuring apparatus according to an aspect of the present invention includes: a touch sensor; a pulse wave measurer configured to measure pulse waves from a user; a contact force measurer including at least three force sensors and configured to measure a contact force between the touch sensor and the user by using the at least three force sensors; a contact area measurer configured to measure a contact area between the user and the touch sensor; and a processor configured to determine a vertical direction error, which indicates a degree of deviation of a direction of force, applied by the user to press the touch sensor, from a vertical direction to a surface of the touch sensor based on sensor values sensed by the at least three force sensors, and estimate blood pressure according to a determination result of the vertical direction error based on the pulse waves, the contact force, and the contact area.

A plurality of modules are simultaneously positioned at locations that correspond to different angiosomes. Each of these modules has a front surface shaped and dimensioned for contacting a person's skin, a plurality of different-wavelength light sources aimed in a forward direction, and a plurality of light detectors aimed to detect light arriving from in front of the front surface. Each module is supported by a support structure (e.g., a strap or a clip) that is shaped and dimensioned to hold the front surface adjacent to the person's skin at a respective position. Perfusion in each of the angiosomes is monitored using these modules, and the surgeon can rely on this information to guide his or her intervention.

The disclosure relates to digital twin of cardiovascular system called as cardiovascular model to generate synthetic Photoplethysmogram (PPG) signal pertaining to disease conditions. The conventional methods are stochastic model capable of generating statistically equivalent PPG signals by utilizing shape parameterization and a nonstationary model of PPG signal time evolution. But these technique generates only patient specific PPG signatures and do not correlate with pathophysiological changes. Further, these techniques like most synthetic data generation techniques lack interpretability. The cardiovascular model of the present disclosure is configured to generate the plurality of synthetic PPG signals corresponding to the plurality of disease conditions. The plurality of synthetic PPG signals can be used to tune Machine Learning algorithms. Further, the plurality of synthetic PPG signals can be utilized to understand, analyze and classify cardiovascular disease progression.

A wearable blood pressure detecting device is provided. The wearable blood pressure detecting device includes a pulse detecting module, a processing unit, a memory unit, a model selecting unit, and a blood pressure calculating unit. The pulse detecting module is configured to generate a pulse waveform. The processing unit is configured to capture the pulse waveform to generate at least one pulse characteristic value. The memory unit is configured to store at least two blood pressure models corresponding to different pulse characteristic value ranges. The model selecting unit is configured to select a corresponding blood pressure model according to the at least one pulse characteristic value. The blood pressure calculating unit is configured to calculate a blood pressure value by the selected blood pressure model.

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.

A blood pressure measuring apparatus according to an aspect of the present invention includes: a touch sensor; a pulse wave measurer configured to measure pulse waves from a user; a contact force measurer including at least three force sensors and configured to measure a contact force between the touch sensor and the user by using the at least three force sensors; a contact area measurer configured to measure a contact area between the user and the touch sensor; and a processor configured to determine a vertical direction error, which indicates a degree of deviation of a direction of force, applied by the user to press the touch sensor, from a vertical direction to a surface of the touch sensor based on sensor values sensed by the at least three force sensors, and estimate blood pressure according to a determination result of the vertical direction error based on the pulse waves, the contact force, and the contact area.

A camera sensitive to near infrared light is placed proximate to the skin of a user and the area illuminated by one or more infrared light sources. A set of images of one or more blood vessels is obtained at successive times. The images are processed to determine a change in size of the vessel(s) from one time to another, corresponding to expansion and contraction of the vessels responsive to contraction of the user's heart. This change may be used to determine pulse rate, elasticity of the vessel, blood pressure, or other data about the user's physiological status. The data may be used to assess health status at a particular time, determine health trends for the user, and so forth.

An electronic device and a method for controlling the electronic device are provided. The electronic device includes a motion sensor and optical sensors. Each of the optical sensors includes a light emitter and a light receiver. The optical sensors are separately driven to determine a respective signal characteristic of each of the optical sensors. A current state of an object to be measured is determined, based on at least one signal received through the motion sensor or the optical sensors. A light emitter of at least one of the optical sensors is driven, based on the respective signal characteristics of the optical sensors according to the current state of the object to be measured. Based on the respective signal characteristics of the optical sensors, a light signal sensed through a light receiver of at least one of the optical sensors is selected and received.