# US 2018/0025502 A1 · Techniques for Accurate Pose Estimation > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2018/0025502 A1 - Document ID: US20180025502A1 - Status: Published application - Kind: A1 - Application number: 15/704,962 - Filed: 2017-09-14 - Published: 2018-01-25 - Earliest claimed: 2014-08-22 - Assignees: Applied Research Associates, Inc. - Applicants: Applied Research Associates, Inc. - Inventors: Alberico Menozzi - Web page: https://patentgrep.com/patent/US20180025502A1 ## CPC - G06T 7/33: using feature-based methods - G01C 21/1654: {with electromagnetic compass} - G01C 21/1656: {with passive imaging devices, e.g. cameras} - G02B 27/0093: {with means for monitoring data relating to the user, e.g. head-tracking, eye-tracking} - G02B 27/017: {Head mounted} - G06F 1/163: {Wearable computers, e.g. on a belt} - G06F 3/011: {Arrangements for interaction with the human body, e.g. for user immersion in virtual reality (blind teaching G09B21/00)} - G06F 3/04817: using icons (graphical or visual programming using iconic symbols G06F8/34) - G06F 11/00: Error detection; Error correction; Monitoring (error detection, correction or monitoring in information storage based on relative movement between record carrier and transducer G11B20/18; monitoring, i.e. supervising the progress of recording or reproducing G11B27/36; in static stores G11C29/00) - G06T 5/20: using local operators - G06T 11/00: Two-dimensional [2D] image generation - G06T 19/006: {Mixed reality (object pose determination, tracking or camera calibration for mixed reality G06T7/00)} - G02B 2027/0138: {comprising image capture systems, e.g. camera} - G02B 2027/0141: {characterised by the informative content of the display} - G02B 2027/0181: {Adaptation to the pilot/driver} - G06F 3/01: Input arrangements or combined input and output arrangements for interaction between user and computer (G06F3/16 takes precedence) - G06T 2200/24: involving graphical user interfaces [GUIs] - G06T: IMAGE DATA PROCESSING OR GENERATION, IN GENERAL - G01C: MEASURING DISTANCES, LEVELS OR BEARINGS; SURVEYING; NAVIGATION; GYROSCOPIC INSTRUMENTS; PHOTOGRAMMETRY OR VIDEOGRAMMETRY (measuring liquid level G01F; radio navigation, determining distance or velocity by use of propagation effects, e.g. Doppler effects, propagation time, of radio waves, analogous arrangements using other waves G01S) - G02B: OPTICAL ELEMENTS, SYSTEMS OR APPARATUS - G06F: ELECTRIC DIGITAL DATA PROCESSING (computer systems based on specific computational models G06N) ## Abstract The described technology regards an augmented reality system and method for estimating a position of a location of interest relative to the position and orientation of a display, including receiving and selectively filtering a plurality of measurement vectors from a rate-gyroscope. Systems of the described technology include including a plurality of sensors, a processing module or other computation means, and a database. Methods of the described technology use data from the sensor package useful to accurately render graphical user interface information on a display. ## Claims ### Claim 1 A pose estimation system for use with a display, the system comprising: a. a plurality of sensors, wherein one of the sensors is a 3-axis angular rate gyro, b. a database comprising geodetic coordinates of a location of interest, and c. a processing module communicatively coupled with the database and the sensors, the processing module receiving a plurality of measurement vectors from the rate-gyroscope and selectively filters the measurement vectors based on a magnitude of each of the measurement vectors such that a rate-gyro signal is selectively filtered using a discrete-time filter, the processing module configured to generate a position and orientation estimate of the display based on the filtered measurement vectors and other data from the sensors, and to calculate a position of the location of interest relative to the display. ### Claim 2 (depends on 1) The pose estimation system of claim 1, wherein the database is remote from the sensors and the processing module. ### Claim 3 (depends on 1) The pose estimation system of claim 1, wherein the plurality of sensors further comprise a camera, a 3-axis accelerometer, a 3-axis magnetometer, a barometric pressure sensor, and a GPS receiver. ### Claim 4 (depends on 1) The pose estimation system of claim 1, wherein the database further comprises digital terrain and elevation data, and the processing module ingests said data to aid in the estimation of altitude of the display. ### Claim 5 (depends on 1) The pose estimation system of claim 1, wherein the plurality of sensors are mounted to a rigid reference assembly. ### Claim 6 (depends on 1) The pose estimation system of claim 1, further comprising a display, and wherein graphical user interface information comprising a graphical icon representing the location of interest, is rendered on the display at the position estimated by the processing module. ### Claim 7 (depends on 6) The pose estimation system of claim 6, further comprising a radio configured to send and receive geo-spatial data relating to objects in the environment, wherein the processing module receives, stores and uses the geo-spatial data to render graphical user interface information on the display comprising a graphical icon representing the objects in the environment. ### Claim 8 (depends on 1) The pose estimation system of claim 1, wherein the processing module implements a baseline GPS/INS to estimate the position of the location of interest, and adjusts the estimated values over time with absolute orientation information. ### Claim 9 (depends on 1) The pose estimation system of claim 1, wherein the position of the location of interest is the vector rdsd, calculated using the formula: rdsd=(CneCbnCdb)T[rese−(repe+CneCbnrpdb)] wherein rpdb is the position of the origin of the display coordinate system d with respect to the point of origin of the body coordinate system p, expressed in body system coordinates b; rese is the position vector of the location of interest s in the environment with respect to the origin of the earth centered, earth fixed coordinate system e, expressed in e coordinates, derived from the geodetic coordinates of the location of interest in the database; and repe is the position of location p with respect to the origin of e, expressed in e coordinates, wherein Cne is an orientation of a North-East-Down (n) coordinate system with respect to e, wherein Cbn is an orientation of b with respect to the North-East-Down (n) coordinate system, and wherein Cdb is the orientation of the display relative to b. ### Claim 10 (depends on 1) The pose estimation system of claim 1, wherein the plurality of sensors further comprises a 3-axis magnetometer, and wherein the processing module compares the norm of data from the 3-axis magnetometer to the Earth's field strength to detect the presence or absence of magnetic disturbances and, upon detection of the presence of magnetic disturbances, rejects data from the magnetometer corresponding to the times of detected magnetic disturbances. ### Claim 11 (depends on 1) The pose estimation system of claim 1, wherein the rate-gyro signal ug is selectively filtered using the discrete-time filter ũg,k=aũg,k−1+(1−a)ug,k with a=Aexp(−0.5∥ug,k−bg∥2/σa2) where 0≦A<1 and σa>0, wherein bg is the current estimate of rate-gyro bias, a is a parameter of the discrete-time filter, ũg,k is the output of the discrete-time filter, ug is the rate-gyro signal, and subscript k indicates discrete time. ### Claim 12 A method for providing an estimate of position for a location of interest relative to a display, the method comprising the steps of: a. receiving a plurality of measurement vectors from a rate-gyroscope, and selectively filtering the measurement vectors based on a magnitude of each of the measurement vectors such that a rate-gyro signal is selectively filtered using a discrete-time filter; b. receiving sensor data from a plurality of sensors comprising delayed data measurements and data representing the spatial position of a display, c. generating a position state estimate of the display based on the filtered measurement vectors and the other received data. ### Claim 13 (depends on 12) The method of claim 12, wherein the rate-gyro signal ug is selectively filtered using the discrete-time filter ũg,k=aũg,k−1+(1−a)ug,k with a=Aexp(−0.5∥ug,k−bg∥2/σa2) where 0≦A<1 and σa>0, wherein bg is the current estimate of rate-gyro bias, a is a parameter of the discrete-time filter, ũg,k is the output of the discrete-time filter, ug is the rate-gyro signal, and subscript k indicates discrete time. ### Claim 14 (depends on 12) The method of claim 12, wherein the sensor data received comprises time-stamped sensor values comprising camera imagery, accelerometer measurements, rate-gyro measurements, magnetometer measurements, barometric pressure sensor measurements, GPS receiver position measurements, and GPS receiver velocity measurements. ### Claim 15 (depends on 12) The method of claim 12, wherein the position of the location of interest is the vector rdsd, calculated using the formula: rdsd=(CneCbnCdb)T[rese−(repe±CneCbnrpdb)] wherein rpdb is the position of the origin of the display coordinate system d with respect to the point of origin of the body coordinate system p, expressed in body system coordinates b; rese is the position vector of the location of interest s in the environment with respect to the origin of the earth centered, earth fixed coordinate system e, expressed in e coordinates, derived from the geodetic coordinates of the location of interest in a database; and repe is the position of location p with respect to the origin of e, expressed in e coordinates, wherein Cne is an orientation of a North-East-Down (n) coordinate system with respect to e, wherein Cbn is an orientation of b with respect to the North-East-Down (n) coordinate system, and wherein Cdb is the orientation of the display relative to b. ### Claim 16 A pose estimation system for use with a display, the system comprising a. means for receiving a plurality of measurement vectors from a rate-gyroscope, and selectively filtering the measurement vectors based on a magnitude of each of the measurement vectors such that a rate-gyro signal is selectively filtered using a discrete-time filter, b. means for receiving sensor data from a plurality of sensors comprising delayed data measurements and data representing the spatial position and orientation of a display, c. means for generating a position estimate for the position and orientation of a display, based on the filtered measurement vectors and the other received data, and d. means for computing a position of a location of interest in relation to the position and orientation of the display. ### Claim 17 (depends on 16) The pose estimation system of claim 16, wherein the rate-gyro signal ug is selectively filtered using the discrete-time filter ũg,k=aũg,k−1+(1−a)ug,k with a=Aexp(−0.5∥ug,k−bg∥2/σa2) where 0≦A<1 and σa>0 wherein bg is the current estimate of rate-gyro bias, a is a parameter of the discrete-time filter, ũg,k is the output of the discrete-time filter, ug is the rate-gyro signal, and subscript k indicates discrete time. ### Claim 18 (depends on 16) The pose estimation system of claim 16, wherein the sensor data received comprises time-stamped sensor values comprising camera imagery, accelerometer measurements, magnetometer measurements, barometric pressure sensor measurements, GPS receiver position measurements, and GPS receiver velocity measurements. ### Claim 19 (depends on 16) The pose estimation system of claim 16, wherein the position of the location of interest is the vector rdsd, calculated using the formula: rdsd=(CneCbnCdb)T[rese−(repe+CneCbnrpdb)] wherein rpdb is the position of the origin of the display coordinate system d with respect to the point of origin of the body coordinate system p, expressed in body system coordinates b; rese is the position vector of the location of interest s in the environment with respect to the origin of the earth centered, earth fixed coordinate system e, expressed in e coordinates, derived from the geodetic coordinates of the location of interest in a database; and repe is the position of location p with respect to the origin of e, expressed in e coordinates, wherein Cne is an orientation of a North-East-Down (n) coordinate system with respect to e, wherein Cbn is an orientation of b with respect to the North-East-Down (n) coordinate system, and wherein Cdb is the orientation of the display relative to b. ### Claim 20 (depends on 16) The pose estimation system of claim 16, further comprising means to render on the display graphical user interface information comprising a graphical icon representing the location of interest at the computed position relative to the display.