# US 2016/0174852 A1 · Weight-bearing biofeedback devices > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2016/0174852 A1 - Document ID: US20160174852A1 - Status: Published application - Kind: A1 - Application number: 14/943,475 - Filed: 2015-11-17 - Published: 2016-06-23 - Earliest claimed: 2014-12-19 - Assignees: Quanttus, Inc. - Applicants: Quanttus, Inc. - Inventors: David Da He; Shahid Azim - Web page: https://patentgrep.com/patent/US20160174852A1 ## CPC - G01G 19/50: having additional measuring devices, e.g. for height - A61B 5/02416: {using photoplethysmograph signals, e.g. generated by infrared radiation (A61B5/14552 takes precedence)} - A61B 5/0285: Measuring or recording phase velocity of blood waves - A61B 5/11: Measuring movement of the entire body or parts thereof, e.g. head or hand tremor or mobility of a limb {(A61B5/1038 takes precedence; motion detection to correct for motion artifacts in physiological signals A61B5/721)} - A61B 5/6887: {mounted on external non-worn devices, e.g. non-medical devices} - A61B 5/7278: {Artificial waveform generation or derivation, e.g. synthesizing signals from measured signals} - A61B 5/0537: Measuring body composition by impedance, e.g. tissue hydration or fat content - A61B 5/1102: {Ballistocardiography} - A61B 5/6807: {Footwear} - A61B 5/6889: {Rooms} - A61B 5/6891: {Furniture} - A61B 5/6892: {Mats} - G01G: WEIGHING (sorting by weighing B07C5/16) - A61B: DIAGNOSIS; SURGERY; IDENTIFICATION (usefulness limited to only animals A61D) ## Abstract A weight-bearing device comprising: a weight-bearing surface configured to bear the weight of a subject; a first sensor module disposed in the device, the first sensor module configured to measure information about pulse waves propagating through blood in the subject, the subject located in contact with the weight-bearing surface; a second sensor module disposed in the device, the second sensor module configured to measure information about a motion of the subject; and a processing device configured to: receive a first dataset representing time-varying information about at least one pulse wave propagating through blood in the subject, wherein the time-varying information about the at least one pulse wave is measured using the first sensor module; receive a second dataset representing information about a time-varying motion of the subject, wherein the information about the time-varying motion is measured using the second sensor module; identify a first point in the first dataset, the first point representing an arrival time of the pulse wave at a first body part of the subject; identify a second point in the second dataset, the second point representing an earlier time at which the pulse wave traverses a second body part of the subject; and compute a pulse transit time (PTT) as a difference between the first and second points, the PTT representing a time taken by the pulse wave to travel from the second body part to the first body part of the subject. ## Claims ### Claim 1 A weight-bearing device comprising: a weight-bearing surface configured to bear the weight of a subject; a first sensor module disposed in the device, the first sensor module configured to measure information about pulse waves propagating through blood in the subject, the subject located in contact with the weight-bearing surface; a second sensor module disposed in the device, the second sensor module configured to measure information about a motion of the subject; and a processing device configured to: receive a first dataset representing time-varying information about at least one pulse wave propagating through blood in the subject, wherein the time-varying information about the at least one pulse wave is measured using the first sensor module; receive a second dataset representing information about a time-varying motion of the subject, wherein the information about the time-varying motion is measured using the second sensor module; identify a first point in the first dataset, the first point representing an arrival time of the pulse wave at a first body part of the subject; identify a second point in the second dataset, the second point representing an earlier time at which the pulse wave traverses a second body part of the subject; and compute a pulse transit time (PTT) as a difference between the first and second points, the PTT representing a time taken by the pulse wave to travel from the second body part to the first body part of the subject. ### Claim 2 (depends on 1) The device of claim 1, wherein the weight-bearing surface is flexible. ### Claim 3 (depends on 2) The device of claim 2, wherein the second sensor module includes a strain gauge. ### Claim 4 (depends on 2) The device of claim 2, wherein the second sensor module includes a motion sensor. ### Claim 5 (depends on 4) The device of claim 4, wherein the motion sensor includes one or both of an accelerometer and a gyroscope. ### Claim 6 (depends on 1) The device of claim 1, wherein the weight-bearing surface is rigid. ### Claim 7 (depends on 1) The device of claim 1, wherein the second sensor module includes a pressure sensor. ### Claim 8 (depends on 1) The device of claim 1, further comprising a mechanism affixed to an underside of the weight-bearing surface, the mechanism configured to permit the weight-bearing surface to depress. ### Claim 9 (depends on 8) The device of claim 8, wherein the mechanism is a spring. ### Claim 10 (depends on 8) The device of claim 8, wherein the second sensor module includes a motion sensor. ### Claim 11 (depends on 10) The device of claim 10, wherein the motion sensor includes one or both of an accelerometer and a gyroscope. ### Claim 12 (depends on 1) The device of claim 1, wherein the first sensor module includes a light source and an optical sensor. ### Claim 13 (depends on 12) The device of claim 12, wherein the light source is an LED. ### Claim 14 (depends on 12) The device of claim 12, wherein the optical sensor is a photodiode. ### Claim 15 (depends on 1) The device of claim 1, wherein the first sensor module includes an impedance sensor. ### Claim 16 (depends on 15) The device of claim 15, wherein the impedance sensor includes two electrodes positioned less than 4 inches of each other. ### Claim 17 (depends on 16) The device of claim 16, wherein the electrodes are positioned such that a part of the skin of the subject makes direct contact with both of the electrodes when the weight-bearing surface bears the weight of the subject. ### Claim 18 (depends on 17) The device of claim 17, wherein the electrodes are positioned such that a foot of the subject makes direct contact with both of the electrodes when the weight-bearing surface bears the weight of the subject. ### Claim 19 (depends on 15) The device of claim 15, wherein the impedance sensor includes two electrodes positioned greater than or equal to 4 inches from each other. ### Claim 20 (depends on 19) The device of claim 19, wherein the electrodes are positioned such that a first foot of the subject makes contact with one of the electrodes and a second foot of the subject makes contact with the other electrode when the weight-bearing surface bears the weight of the subject. ### Claim 21 (depends on 1) The device of claim 1, wherein the information about pulse waves propagating through blood in the subject comprises photoplethysmographic (PPG) data. ### Claim 22 (depends on 1) The device of claim 1, wherein the information about pulse waves propagating through blood in the subject comprises bio-impedance data. ### Claim 23 (depends on 1) The device of claim 1, wherein the information about a motion of the subject comprises ballistocardiogram (BCG) data. ### Claim 24 (depends on 1) The device of claim 1, wherein the information about a motion of the subject comprises seismocardiogram (SCG) data. ### Claim 25 (depends on 1) The device of claim 1, wherein identifying the first point in the first dataset includes identifying a reference point within the first dataset. ### Claim 26 (depends on 25) The device of claim 25, wherein the reference point is a local maximum, a local minimum, a zero-crossing, or a local maximum of a first derivative within the first dataset. ### Claim 27 (depends on 25) The device of claim 25, wherein the reference point is within an expected range of one or both of time and amplitude. ### Claim 28 (depends on 1) The device of claim 1, wherein identifying the second point in the second dataset includes identifying a reference point within the second dataset. ### Claim 29 (depends on 28) The device of claim 28, wherein the reference point is a local maximum, a local minimum, a zero-crossing, or a local maximum of a first derivative within the first dataset. ### Claim 30 (depends on 28) The device of claim 28, wherein the reference point is within an expected range of one or both of time and amplitude. ### Claim 31 (depends on 1) The device of claim 1, wherein the weight-bearing surface is substantially flat. ### Claim 32 (depends on 1) The device of claim 1, wherein at least one of the first sensor module and the second sensor module is attached to the weight-bearing surface. ### Claim 33 (depends on 1) The device of claim 1, wherein the weight-bearing surface is configured to directly contact the subject when the weight-bearing surface bears the weight of the subject. ### Claim 34 (depends on 1) The device of claim 1, wherein the device is a weight scale. ### Claim 35 (depends on 1) The device of claim 1, wherein the device is integrated into a floor. ### Claim 36 (depends on 35) The device of claim 35, wherein the device is a floor tile. ### Claim 37 (depends on 1) The device of claim 1, wherein the device is a bed. ### Claim 38 (depends on 1) The device of claim 1, wherein the device is a yoga mat. ### Claim 39 (depends on 1) The device of claim 1, wherein the device is a shoe. ### Claim 40 (depends on 39) The device of claim 39, wherein the weight-bearing surface is a sole of the shoe. ### Claim 41 (depends on 40) The device of claim 40, wherein at least one of the first sensor module and the second sensor module is attached to the sole of the shoe. ### Claim 42 (depends on 1) The device of claim 1, wherein the device is a chair. ### Claim 43 (depends on 1) The device of claim 1, wherein the second sensor module includes a sensor for measuring a weight of the subject. ### Claim 44 (depends on 1) The device of claim 1, wherein the processing device is further configured to determine one or more of a blood pressure, a heart rate, a respiratory rate, a blood oxygen level, a stroke volume, a cardiac output, and a temperature of the subject. ### Claim 45 (depends on 44) The device of claim 44, wherein the processing device determines the heart rate, the respiratory rate, the stroke volume, and the cardiac output based on the information measured by the second sensor module without using the information measured by the first sensor module. ### Claim 46 (depends on 1) The device of claim 1, wherein the second sensor module is configured to measure a weight of the subject. ### Claim 47 (depends on 15) The device of claim 15, wherein the device is configured to measure a body composition of the subject. ### Claim 48 (depends on 47) The device of claim 47, wherein the body composition of the subject includes a fat content of the subject. ### Claim 49 A device comprising: a weight-bearing surface configured to bear the weight of a subject; a first sensor module and a second sensor module each disposed in the device, the first sensor module and the second sensor module each configured to measure information about pulse waves propagating through blood in the subject, the subject located in contact with the weight-bearing surface; and a processing device configured to: receive a first dataset representing time-varying information about at least one pulse wave propagating through blood in the subject, wherein the time-varying information about the at least one pulse wave is measured using the first sensor module; receive a second dataset representing time-varying information about the at least one pulse wave propagating through blood in the subject, wherein the time-varying information about the at least one pulse wave is measured using the second sensor module; identify a first point in the first dataset, the first point representing an arrival time of the pulse wave at a first body part of the subject; identify a second point in the second dataset, the second point representing an arrival time of the pulse wave at a second body part of the subject; and compute a pulse transit time (PTT) as a difference between the first and second points, the PTT representing a time taken by the pulse wave to travel from the first body part to the second body part of the subject. ### Claim 50 (depends on 49) The device of claim 49, wherein at least one of the first sensor module and the second sensor module includes a light source and an optical sensor. ### Claim 51 (depends on 50) The device of claim 50, wherein the light source is an LED. ### Claim 52 (depends on 50) The device of claim 50, wherein the optical sensor is a photodiode. ### Claim 53 (depends on 49) The device of claim 49, wherein at least one of the first sensor module and the second sensor module includes an impedance sensor. ### Claim 54 (depends on 53) The device of claim 53, wherein the impedance sensor includes two electrodes positioned less than 4 inches of each other. ### Claim 55 A device comprising: a weight-bearing surface configured to bear the weight of a subject; a first sensor module disposed in the device, the first sensor module configured to measure information about pulse waves propagating through blood in the subject, the subject located in contact with the weight-bearing surface; a second sensor module disposed in the device, the second sensor module configured to measure information about electrical signals related to the heart of the subject; and a processing device configured to: receive a first dataset representing time-varying information about at least one pulse wave propagating through blood in the subject, wherein the time-varying information about the at least one pulse wave is measured using the first sensor module; receive a second dataset representing time-varying information about electrical signals related to the heart of the subject, wherein the time-varying information about electrical signals related to the heart of the subject is measured using the second sensor module; identify a first point in the first dataset, the first point representing an arrival time of the pulse wave at a body part of the subject; identify a second point in the second dataset, the second point representing an earlier time at which the heart of the subject is depolarized, wherein the pulse wave is originated from the heart of the subject in response to the depolarization; and compute a pulse arrival time (PAT) as a difference between the first and second points, the PAT representing an elapsed time between the pulse wave being originated and the pulse wave arriving at the body part of the subject. ### Claim 56 (depends on 55) The device of claim 55, wherein the PAT represents an approximate time taken by the pulse wave to travel from the heart of the subject to the body part of the subject.