# US 12,111,434 B2 · MEMS-based rotation sensor for seismic applications and sensor units having same > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,111,434 B2 - Document ID: US12111434B2 - Status: Granted - Kind: B2 - Application number: 18/050,248 - Filed: 2022-10-27 - Published: 2023-03-09 - Granted: 2024-10-08 - Earliest claimed: 2012-12-19 - Assignees: Schlumberger Technology Corporation - Applicants: Schlumberger Technology Corporation - Inventors: Maxime Projetti; Olivier Vancauwenberghe; Nicolas Goujon; Hans Paulson - Web page: https://patentgrep.com/patent/US12111434B2 ## CPC - G01V 1/164: {Circuits therefore} - G01P 15/125: by capacitive pick-up - G01V 1/003: {Seismic data acquisition in general, e.g. survey design (G01V1/3808, G01V1/42 take precedence)} - G01V 1/18: Receiving elements, e.g. seismometer, geophone {or torque detectors, for localised single point measurements} - G01V 1/3808: {Seismic data acquisition, e.g. survey design} - G01C 19/5712: the devices involving a micromechanical structure - G01V 1/189: {Combinations of different types of receiving elements} - G01V 1/38: specially adapted for water-covered areas (G01V1/28 takes precedence) - G01V: GEOPHYSICS; GRAVITATIONAL MEASUREMENTS; DETECTING MASSES OR OBJECTS; TAGS (means for indicating the location of accidentally buried, e.g. snow-buried, persons A63B29/02) - 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}) - 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 The present disclosure is directed to a MEMS-based rotation sensor for use in seismic data acquisition and sensor units having same. The MEMS-based rotation sensor includes a substrate, an anchor disposed on the substrate and a proof mass coupled to the anchor via a plurality of flexural springs. The proof mass has a first electrode coupled to and extending therefrom. A second electrode is fixed to the substrate, and one of the first and second electrodes is configured to receive an actuation signal, and another of the first and second electrodes is configured to generate an electrical signal having an amplitude corresponding with a degree of angular movement of the first electrode relative to the second electrode. The MEMS-based rotation sensor further includes closed loop circuitry configured to receive the electrical signal and provide the actuation signal. Related methods for using the MEMS-based rotation sensor in seismic data acquisition are also described. ## Claims ### Claim 1 A seismic data acquisition system, comprising: one or more sources configured to generate seismic waves; and one or more sensor units configured to record seismic waves generated by the one or more sources, the one or more sensor units comprising a first seismic sensor configured to measure a vertical wavefield of the seismic waves, and a second seismic sensor configured to measure a gradient of the vertical wavefield, wherein the second seismic sensor comprises: an anchor disposed on a substrate; a proof mass coupled to the anchor via a plurality of flexural springs, the proof mass having a first electrode adapted to move with the proof mass; and a second electrode disposed on the substrate, one of the first and second electrodes being configured to generate an electrical signal having an amplitude corresponding with a degree of angular movement of the first electrode relative to the second electrode or the second electrode relative to the first electrode. ### Claim 2 (depends on 1) The seismic data acquisition system of claim 1, wherein the one or more sources comprise one or more air guns. ### Claim 3 (depends on 1) The seismic data acquisition system of claim 1, comprising one or more streamers, wherein the one or more streamers comprise the one or more sensor units. ### Claim 4 (depends on 1) The seismic data acquisition system of claim 1, wherein the first seismic sensor is configured to measure a first set of components of a particle motion comprising a particle displacement, a second set of components of a particle velocity, and a third set of components of a particle acceleration. ### Claim 5 (depends on 4) The seismic data acquisition system of claim 4, wherein the first seismic sensor comprises a particle displacement sensor configured to measure the particle displacement. ### Claim 6 (depends on 1) The seismic data acquisition system of claim 1, wherein the first seismic sensor comprises a one-component particle velocity sensor. ### Claim 7 (depends on 1) The seismic data acquisition system of claim 1, wherein the first seismic sensor comprises a three-component particle motion sensor. ### Claim 8 (depends on 7) The seismic data acquisition system of claim 7, wherein the three-component particle motion sensor comprises a three-component particle accelerometer configured to measure one or more components of a particle acceleration. ### Claim 9 (depends on 1) The seismic data acquisition system of claim 1, wherein the gradient of the vertical wavefield comprises a first horizontal gradient of the vertical wavefield. ### Claim 10 (depends on 9) The seismic data acquisition system of claim 9, comprising a third seismic sensor for measuring a second horizontal gradient of the vertical wavefield, wherein the third seismic sensor is a microelectromechanical system (MEMS) sensor positioned orthogonally to the second seismic sensor, and wherein the second horizontal gradient is orthogonally to the first horizontal gradient. ### Claim 11 (depends on 1) The seismic data acquisition system of claim 1, comprising a hydrophone or a pressure gradient sensor. ### Claim 12 (depends on 1) The seismic data acquisition system of claim 1, wherein the one or more sensor units are configured to measure angular accelerations of vibration noise. ### Claim 13 (depends on 1) The seismic data acquisition system of claim 1, wherein the first seismic sensor and the second seismic sensor are configured to generate electrical signals that are sent through closed loop circuitry configured to provide an actuation signal. ### Claim 14 (depends on 13) The seismic data acquisition system of claim 13, wherein the electrical signals comprise analog signals and the closed loop circuitry is configured to convert the analog signals into respective bit stream sequences. ### Claim 15 (depends on 14) The seismic data acquisition system of claim 14, wherein the closed loop circuitry comprises a force feedback generator for receiving the respective bit stream sequences and converting the respective bit stream sequences into the actuation signal. ### Claim 16 A sensor assembly, comprising: a first seismic sensor configured to measure one or more components of a particle motion associated with seismic waves; a second seismic sensor configured to measure a gradient of one of the one or more components of the particle motion, wherein the second seismic sensor comprises: an anchor disposed on a substrate; a proof mass coupled to the anchor via a plurality of flexural springs, the proof mass having a first electrode adapted to move with the proof mass; and a second electrode disposed on the substrate, one of the first and second electrodes being configured to generate an electrical signal having an amplitude corresponding with a degree of angular movement of the first electrode relative to the second electrode or the second electrode relative to the first electrode; and a third seismic sensor configured to measure a pressure wavefield associated with the seismic waves. ### Claim 17 (depends on 16) The sensor assembly of claim 16, wherein the first seismic sensor comprises a microelectromechanical system (MEMS) translational accelerometer configured to measure translational accelerations of the particle motion. ### Claim 18 (depends on 16) The sensor assembly of claim 16, wherein the second seismic sensor comprises a microelectromechanical system (MEMS) sensor configured to measure angular accelerations of the particle motion. ### Claim 19 A sensor unit, comprising: a first microelectromechanical system (MEMS) sensor configured to measure one or more components of a particle motion associated with seismic waves generated by one or more sources; a second MEMS sensor configured to measure a gradient of one of the one or more components of the particle motion, wherein the second MEMS sensor comprises: an anchor disposed on a substrate; a proof mass coupled to the anchor via a plurality of flexural springs, the proof mass having a first electrode adapted to move with the proof mass; and a second electrode disposed on the substrate, one of the first and second electrodes being configured to generate an electrical signal having an amplitude corresponding with a degree of angular movement of the first electrode relative to the second electrode or the second electrode relative to the first electrode; and a seismic sensor configured to measure a pressure wavefield associated with the seismic waves. ### Claim 20 (depends on 19) The sensor unit of claim 19, comprising closed loop circuitry configured to receive the electrical signal having the amplitude corresponding with the degree of angular movement of the first electrode positioned within the sensor unit relative to the second electrode positioned within the sensor unit, wherein the closed loop circuitry comprises a sigma-delta modulator and the electrical signal passes through the sigma-delta modulator.