# US 2013/0158940 A1 · Vestibular dynamic inclinometer > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2013/0158940 A1 - Document ID: US20130158940A1 - Status: Published application - Kind: A1 - Application number: 13/665,872 - Filed: 2012-10-31 - Published: 2013-06-20 - Earliest claimed: 2011-10-31 - Assignees: University of Florida Research Foundation, Inc. - Inventors: Carl D. Crane, III; Vishesh Vikas - Web page: https://patentgrep.com/patent/US20130158940A1 ## CPC - G06F 17/00: Digital computing or data processing equipment or methods, specially adapted for specific functions (information retrieval, database structures or file system structures therefor G06F16/00) - G01C 9/02: Details - G06F: ELECTRIC DIGITAL DATA PROCESSING (computer systems based on specific computational models G06N) - 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) ## Abstract A method of determining orientation parameters of a rigid body (72, 184), including: associating at least two multi-axis accelerometers (40, 42, 202, 204, 206, 208) with the rigid body, wherein the body has a base end 76, 188), a distal end (77, 190), and a line of symmetry between the base end and the distal end. The two first multi-axis accelerometers (40, 42) (202, 204) are disposed at a first point (80, 212) along the line of symmetry between the base end and the distal end. Each first multi-axis accelerometer is disposed at equal distances from the line of symmetry. The line of symmetry and both first multi-axis accelerometers lie in a first plane. The method further includes: associating a gyroscope (46, 210) with the body at the first point, equally between both first multi-axis accelerometers; gathering measured data from the two first multi-axis accelerometers and the gyroscope; and applying analysis free of calculus to determine a first inclination angle (88) (192), of the body from a stable orientation. ## Claims ### Claim 1 A method of determining orientation parameters of a rigid body, comprising: associating at least two multi-axis accelerometers with the body, wherein the body comprises a base end, a distal end, and a line of symmetry of the body between the base end and the distal end, wherein two first multi-axis accelerometers are disposed at a first point along the line of symmetry between the base end and the distal end, wherein each first multi-axis accelerometer is disposed at equal distances from the line of symmetry, and wherein the line of symmetry and both first multi-axis accelerometers lie in a first plane; associating a gyroscope with the body; gathering measured data from the two first multi-axis accelerometers and the gyroscope; and applying analysis free of calculus to determine a first inclination angle of the line of symmetry from a stable orientation. ### Claim 2 (depends on 1) The method of claim 1, further comprising applying the analysis free of calculus to determine a magnitude of total acceleration acting on the body. ### Claim 3 (depends on 1) The method of claim 1, wherein the inclination angle is from a dynamic equilibrium axis, and wherein the dynamic equilibrium axis is parallel to a direction of a total acceleration a point of contact on the body. ### Claim 4 (depends on 3) The method of claim 3, wherein the total acceleration includes gravity and an acceleration other than gravity. ### Claim 5 (depends on 3) The method of claim 3, wherein the body moves within the first plane, wherein the dynamic equilibrium axis is disposed within the first plane, and wherein the inclination angle is within the first plane. ### Claim 6 (depends on 5) The method of claim 5, wherein first axes of the first multi-axis accelerometers are disposed within the first plane and are perpendicular to the line of symmetry, and wherein second axes of the first multi-axis accelerometers are disposed within the first plane and are parallel to the line of symmetry. ### Claim 7 (depends on 6) The method of claim 6, wherein the first multi-axis accelerometers comprise dual axis accelerometers. ### Claim 8 (depends on 1) The method of claim 1, wherein the gyroscope comprises a single axis gyroscope. ### Claim 9 (depends on 4) The method of claim 4, further comprising: associating a two second multi-axis accelerometers at the first point, wherein each second multi-axis accelerometer is disposed at equal distances from the line of symmetry, and wherein the line of symmetry and both first multi-axis accelerometers lie in a second plane that is perpendicular to the first plane; and determining a second inclination angle, wherein the base end is constrained to move on a third surface transverse to the first plane and the second plane; wherein the first plane and the second plane intersect each other at the base end, wherein the body is free to rotate and limited to movement in the first plane and in the second plane, and wherein the first inclination angle and the second inclination angle determine an overall inclination from the dynamic equilibrium axis. ### Claim 10 (depends on 9) The method of claim 9, wherein each first multi-axis accelerometer comprises a first axis oriented perpendicular to the first plane and a second axis within the first plane and parallel to the line of symmetry, and wherein each second multi-axis accelerometer comprises a first axis oriented perpendicular to the second plane and a second axis within the second plane and parallel to the line of symmetry. ### Claim 11 (depends on 10) The method of claim 10, wherein the first multi-axis accelerometers and the two second multi-axis accelerometers comprise dual axis accelerometers. ### Claim 12 (depends on 1) The method of claim 1, wherein measured data is sampled as discrete sets of measure data over time, and wherein inclination parameters are determined as a set of inclination parameters derived solely from a respective set of measured data. ### Claim 13 An apparatus for determining inclination parameters of a body, comprising: a gyroscope configured to be disposed on the body; at least two multi-axis accelerometers configured to be secured with respect to the first point such that two first multi-axis accelerometers are disposed symmetrically about the first point, and the line of symmetry and the two first multi-axis accelerometers lie in a first plane. ### Claim 14 (depends on 13) The apparatus of claim 13, further comprising a processor configured to determine an inclination angle of the body with respect to a dynamic equilibrium angle that is parallel to a direction of a total acceleration acting on the body, wherein the total acceleration comprises gravity and may or may not comprise an acceleration other than gravity. ### Claim 15 (depends on 13) The apparatus of claim 13, wherein when the body is configured such that a movement of the body is limited to the first plane, each of the first multi-axis accelerometers comprise first axes disposed within the first plane and perpendicular to the line of symmetry and second axes disposed within the first plane and parallel to the line of symmetry. ### Claim 16 (depends on 15) The apparatus of claim 15, wherein the two first multi-axis accelerometers, and the gyroscope comprises a tri-axial gyroscope. ### Claim 17 (depends on 13) The apparatus of claim 13, further comprising two second multi-axis accelerometers configured to be secured with respect to the first point such that the two second multi-axis accelerometers are disposed symmetrically about the first point, and the line of symmetry and the two second multi-axis accelerometers lie in a second plane perpendicular to the first plane. ### Claim 18 (depends on 17) The apparatus of claim 17, wherein when the body is configured such that a movement of the base end is limited to a surface transverse to the first plane and the second plane, the first plane and the second plane intersect each other at the base end, the body is free to rotate and movement is of the body is limited to the first plane and the second plane, and wherein each first multi-axis accelerometer comprises a first axis oriented perpendicular to the first plane and a second axis within the first plane and parallel to the line of symmetry, and each second multi-axis accelerometer comprises a first axis oriented perpendicular to the second plane and a second axis within the second plane and parallel to the line of symmetry. ### Claim 19 (depends on 18) The apparatus of claim 18, wherein the two first multi-axis accelerometers comprise dual axis accelerometers.