# US 11,439,325 B2 · Wireless and retrofittable in-shoe system for real-time estimation of kinematic and kinetic gait parameters > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,439,325 B2 - Document ID: US11439325B2 - Status: Granted - Kind: B2 - Application number: 16/457,730 - Filed: 2019-06-28 - Published: 2020-01-02 - Granted: 2022-09-13 - Earliest claimed: 2018-06-29 - Assignees: The Trustees of the Stevens Institute of Technology; The Trustees of Columbia University in the City of New York - Applicants: The Trustees of the Stevens Institute of Technology; The Trustees of Columbia University In the City of New York - Inventors: Damiano Zanotto; Sunil K. Agrawal; Huanghe Zhang - Web page: https://patentgrep.com/patent/US11439325B2 ## CPC - A61B 5/112: {Gait analysis} - A61B 5/0004: {characterised by the type of physiological signal transmitted} - A61B 5/0022: {Monitoring a patient using a global network, e.g. telephone networks, internet} - A61B 5/1038: {Measuring plantar pressure during gait} - A61B 5/1112: {Global tracking of patients, e.g. by using GPS} - A61B 5/486: {Biofeedback (using electroencephalography [EEG] A61B5/375)} - A61B 5/6807: {Footwear} - A61B 5/7264: {Classification of physiological signals or data, e.g. using neural networks, statistical classifiers, expert systems or fuzzy systems} - G16H 40/67: for remote operation - A61B 2505/09: Rehabilitation or training - A61B 2562/0247: Pressure sensors - A61B 2562/046: in a matrix array - A61B: DIAGNOSIS; SURGERY; IDENTIFICATION (usefulness limited to only animals A61D) - G16H: HEALTHCARE INFORMATICS, i.e. INFORMATION AND COMMUNICATION TECHNOLOGY [ICT] SPECIALLY ADAPTED FOR THE HANDLING OR PROCESSING OF MEDICAL OR HEALTHCARE DATA ## Abstract A quantitative gait training and/or analysis system includes one or more footwear modules that may include a piezoresistive sensor, an inertial sensor and an independent logic unit. The footwear module functions to permit the extraction of gait kinematics and evaluation thereof in real time, or data may be stored for later reduction and analysis. Embodiments relating to calibration-based estimation of kinematic gait parameters are described. ## Claims ### Claim 1 A method for calibrating a gait measurement system, comprising the steps of: i) providing an instrumented insole having a plurality of pressure-sensing cells; ii) exerting a fixed, uniform pressure on said instrumented insole; iii) recording a respective output for each of said pressure-sensing cells in response to pressure exerted on said instrumented insole during the performance of step (ii); iv) applying a plurality of fitting functions to said respective output of each of said pressure-sensing cells, thereby obtaining a plurality of respective model data; and v) applying cross validation to said plurality of respective model data to obtain a calibration model for each of said pressure-sensing cells. ### Claim 2 (depends on 1) The method of claim 1, wherein at least one pressure-sensing cell of said plurality of pressure-sensing cells comprises a piezoresistive sensor. ### Claim 3 (depends on 1) The method of claim 1, wherein said plurality of pressure-sensing cells includes eight pressure-sensing cells. ### Claim 4 (depends on 1) The method of claim 1, further comprising the step of locating at least some of said plurality of pressure-sensing cells beneath a user's calcaneous, a user's lateral arch, a head of a user's first metatarsal, a head of a user's third metatarsal, a head of a user's fifth metatarsal, a user's hallux and/or a user's toes. ### Claim 5 (depends on 1) The method of claim 1, further comprising the step of retrofitting said instrumented insole to a shoe of a user. ### Claim 6 (depends on 1) The method of claim 1, further comprising the step of providing said instrumented insole with an inertial sensor. ### Claim 7 (depends on 6) The method of claim 6, wherein said inertial sensor has nine-degrees of freedom. ### Claim 8 (depends on 6) The method of claim 6, further comprising the step of locating said inertial sensor along a portion of said instrumented insole corresponding to a midline of a user's foot. ### Claim 9 (depends on 1) The method of claim 1, further comprising the step of providing vibro-tactile feedback to a user from said instrumented insole. ### Claim 10 (depends on 1) The method of claim 1, further comprising the step of providing said instrumented insole with a logic unit configured to sample data at 500 Hertz. ### Claim 11 (depends on 1) The method of claim 1, further comprising the step of estimating center of pressure and/or dynamic margin of stability. ### Claim 12 (depends on 1) The method of claim 1, further comprising the step of measuring inter-limb parameters. ### Claim 13 (depends on 1) The method of claim 1, further comprising the step of measuring one or more gait parameters selected from the group consisting of stride length, foot-ground clearance, foot trajectory, cadence, double support time, single support time, walking speed, center of pressure, and margin of stability. ### Claim 14 (depends on 13) The method of claim 13, further comprising the step of generating dynamic plantar pressure maps and/or center of pressure trajectories. ### Claim 15 (depends on 1) The method of claim 1, further comprising the step of classifying activities of daily living. ### Claim 16 (depends on 1) The method of claim 1, wherein said method is implemented in connection with a mobile device having GPS in order to realize a portable navigation system. ### Claim 17 (depends on 1) The method of claim 1, further comprising the steps of remotely monitoring and administering walking and/or balance exercises. ### Claim 18 (depends on 1) The method of claim 1, wherein said method is implemented in a device used for gait and/or balance rehabilitation. ### Claim 19 A method for calibrating a gait measurement system, comprising the steps of: i) providing an instrumented insole and a reference source; ii) recording a first data set from said instrumented insole and a second data set from said reference source; iii) computing center of pressure trajectories from said first data set and said second data set; iv) validating said center of pressure trajectories using one or more regression models; and v) calibrating said instrumented insole via said first data set and said second data set. ### Claim 20 (depends on 19) The method of claim 19, further comprising the step of retrofitting said instrumented insole to a shoe of a user. ### Claim 21 (depends on 19) The method of claim 19, further comprising the step of providing said instrumented insole with an inertial sensor. ### Claim 22 (depends on 21) The method of claim 21, wherein said inertial sensor has nine-degrees of freedom. ### Claim 23 (depends on 21) The method of claim 21, further comprising the step of locating said inertial sensor along a portion of said instrumented insole corresponding to a midline of a user's foot. ### Claim 24 (depends on 19) The method of claim 19, further comprising the step of providing vibro-tactile feedback to a user from said instrumented insole. ### Claim 25 (depends on 19) The method of claim 19, further comprising the step of providing said instrumented insole with a logic unit configured to sample data at 500 Hertz. ### Claim 26 (depends on 19) The method of claim 19, further comprising the step of estimating center of pressure and/or dynamic margin of stability. ### Claim 27 (depends on 19) The method of claim 19, further comprising the step of measuring inter-limb parameters. ### Claim 28 (depends on 19) The method of claim 19, further comprising the step of measuring one or more gait parameters selected from the group consisting of stride length, foot-ground clearance, foot trajectory, cadence, double support time, single support time, walking speed, center of pressure, and margin of stability. ### Claim 29 (depends on 28) The method of claim 28, further comprising the step of generating dynamic plantar pressure maps and/or center of pressure trajectories. ### Claim 30 (depends on 19) The method of claim 19, further comprising the step of classifying activities of daily living. ### Claim 31 (depends on 19) The method of claim 19, wherein said method is implemented in connection with a mobile device having GPS in order to realize a portable navigation system. ### Claim 32 (depends on 19) The method of claim 19, further comprising the steps of remotely monitoring and administering walking and/or balance exercises. ### Claim 33 (depends on 19) The method of claim 19, wherein said method is implemented in a device used for gait and/or balance rehabilitation.