# US 10,307,086 B2 · Gait measurement with 3-axes accelerometer/gyro in mobile devices > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,307,086 B2 - Document ID: US10307086B2 - Status: Granted - Kind: B2 - Application number: 14/622,933 - Filed: 2015-02-16 - Published: 2015-08-20 - Granted: 2019-06-04 - Earliest claimed: 2014-02-17 - Assignees: Hong Kong Baptist University - Applicants: Hong Kong Baptist University - Inventors: Jeffrey Tai Kin Cheung - Web page: https://patentgrep.com/patent/US10307086B2 ## CPC - A61B 5/112: {Gait analysis} - A61B 5/1123: {Discriminating type of movement, e.g. walking or running (A61B5/1116, A61B5/112 take precedence)} - A61B 5/6898: {Portable consumer electronic devices, e.g. music players, telephones, tablet computers} - A61B 5/7235: {Details of waveform analysis (detecting specific parameters of the electrocardiograph cycle A61B5/349)} - A61B 5/7242: {using integration} - G01P 15/00: Measuring acceleration; Measuring deceleration; Measuring shock, i.e. sudden change of acceleration - A61B 2562/0219: Inertial sensors, e.g. accelerometers, gyroscopes, tilt switches - A61B: DIAGNOSIS; SURGERY; IDENTIFICATION (usefulness limited to only animals A61D) - G01P: MEASURING LINEAR OR ANGULAR SPEED, ACCELERATION, DECELERATION, OR SHOCK; INDICATING PRESENCE, ABSENCE, OR DIRECTION, OF MOVEMENT (measuring or recording blood flow A61B5/02, A61B8/06; monitoring speed or deceleration of electrically-propelled vehicles B60L3/00; vehicle lighting systems adapted to indicate speed B60Q1/54; determining position or course in navigation, measuring ground distance in geodesy or surveying G01C; combined measuring devices for measuring two or more variables of movement G01C23/00; measuring velocity of sound G01H; measuring velocity of light G01J7/00; measuring direction or velocity of solid objects by reception or emission of radiowaves or other waves and based on propagation effects, e.g. Doppler effect, propagation time, direction of propagation, G01S; measuring speed of nuclear radiation G01T; measuring acceleration of gravity G01V; {measuring or recording the speed of trains B61L23/00; speed indicators incorporated in motor vehicles B60K35/00; measuring frequency or phase G01R; traffic control G08G}) ## Abstract The present invention relates to a method of gait measurement using tri-axial accelerometer/gyro in mobile devices. In particular, the present invention relates to a method of gait measurement using tri-axial accelerometer/gyro in mobile devices for monitoring and improving the physical movement of a moving subject. ## Claims ### Claim 1 A method for real-time measurement of gait imperfection in a human subject, the method comprising: placing a mobile communication device against a lower back of said human subject, wherein the mobile communication device is equipped with a tri-axial accelerometer or a gyro; measuring in real-time under a sampling frequency, by the mobile communication device, walking, heaving and lateral movements of said human subject, wherein the sample frequency is determined based on a movement pattern of the human subject; constructing in real-time a signature of said subject based on movements measured by the mobile communication device; wherein the signature is a three-dimensional trajectory in orthogonal directions of said subject's center of gravity's acceleration trajectory, the three-dimensional trajectory comprising direction and magnitude of acceleration components of the movements, and phase relationships between the acceleration components of the movements in different directions; constructing in real-time a power level (Wij) dispensed by said subject to keep balance during motion quantitatively based on said signature by computing a summation of forces associated with individual segments along a trajectory of the center of gravity of said subject divided by a total measurement time; and generating an output to indicate the gait imperfection in the human subject, wherein the generated output comprises the constructed signature and the constructed power level. ### Claim 2 (depends on 1) The method according to claim 1, wherein said signature is used in monitoring, diagnosing and improving the movement performance of said human subject. ### Claim 3 (depends on 1) The method according to claim 1, wherein said signature is used in monitoring the progress of physical rehabilitation or physical well-being or both of said human subject via the movement of said human subject. ### Claim 4 (depends on 1) The method according to claim 1, wherein said signature is used in the designing or fitting of prosthesis or both for said human subject. ### Claim 5 (depends on 1) The method according to claim 1, wherein said signature is used as a biometric identifier of said human subject. ### Claim 6 (depends on 1) The method according to claim 1, wherein said signature is used as an indicator for physical impairment analysis of said human subject. ### Claim 7 (depends on 1) The method according to claim 1, wherein said signature is used as an identifier for selecting human subjects with better form of movement. ### Claim 8 (depends on 1) The method according to claim 1, wherein said signature is used in designing of footwear for said human subject. ### Claim 9 (depends on 1) The method according to claim 1, wherein said signature is used as an indicator in the fitting and selecting footwear for said human subject. ### Claim 10 (depends on 1) The method according to claim 1, wherein said signature is used in the designing of an exercise equipment for said human subject. ### Claim 11 (depends on 1) The method according to claim 1, wherein said signature is used in the designing of backpacks and other forms of carry luggage for said human subject. ### Claim 12 (depends on 1) The method according to claim 1, wherein said sampling frequency is 100 Hz or higher. ### Claim 13 (depends on 1) The method according to claim 1, wherein sensitivity of said tri-axial accelerometer or gyro is approximately 0.003 g. ### Claim 14 (depends on 1) The method according to claim 1, further comprising: formulating a reference table of a plurality of said power levels of a plurality of human subjects with a plurality of fitness levels under a plurality of conditions; measuring gait imperfection of said human subject based on the obtained power level of said human subject in reference to said reference table; and correcting said gait imperfection of said human subject through external activity. ### Claim 15 An apparatus for real-time measurement of gait imperfection in a human subject comprising: a mobile communication device having a tri-axial accelerometer or a gyro placed against a lower back of said human subject and configured to measure in real-time under a sampling frequency walking, heaving and lateral movements of said human subject, wherein the sample frequency is determined based on a movement pattern of the human subject; a computer processor configured to: constructing in real-time a signature of said subject based on movements measured by the mobile communication device; wherein the signature is a three-dimensional trajectory in orthogonal directions of said human subject's center of gravity's acceleration trajectory, the three-dimensional trajectory comprising direction and magnitude of acceleration components of the movements, and phase relationship between the acceleration components of the movements in different directions; and constructing in real-time a power level dispensed by said human subject to keep balance during motion quantitatively based on said signature by computing a summation of forces associated with individual segments along a trajectory of the center of gravity of said human subject divided by a total measurement time; and generating an output to indicate the gait imperfection in the human subject, wherein the generated output comprises the constructed signature and the constructed power level.