公开(公告)号：US11340248B2

公开(公告)日：2022-05-24

申请号：US16511433

申请日：2019-07-15

Applicant: Atlantic Inertial Systems Limited

Inventor： Alan Malvern ,  Kiran Harish

IPC: G01P1/02 ,  G01P1/00

Abstract: A sensor package comprising: a sensor, wherein the sensor comprises a sensing structure formed in a material layer and one or more further material layers arranged to seal the sensing structure to form a hermetically sealed sensor unit; a support structure; one or more springs flexibly fixing the hermetically sealed sensor unit to the support structure; wherein the one or more springs are formed in the same material layer as the sensing structure of the sensor unit; and one or more external package wall(s) encapsulating the sensor unit, the support structure, and the one or more springs, wherein the support structure is fixed to at least one of the package wall(s). The springs decouple mechanical stresses between the sensor unit and the external package wall(s) so as to reduce the long term drift of scale factor and bias.

公开(公告)号：US11150091B2

公开(公告)日：2021-10-19

申请号：US15758948

申请日：2016-08-11

Applicant: ATLANTIC INERTIAL SYSTEMS LIMITED

Inventor： Alan Malvern

IPC: G01C19/5684

Abstract: An angular velocity sensor comprises: an insulative support layer (10); a substrate layer (8) formed of a silica-based material and comprising a planar ring structure (2) mounted to vibrate in-plane; and a plurality of conductive electrodes (14), each comprising a first set of moveable conductive electrode tracks (14a) formed on a surface of the planar ring and a second set of fixed conductive electrode tracks (14b) formed on a surface of the insulative support layer axially spaced from the surface of the planar ring. The first and second sets of conductive electrode tracks are interdigitated with a lateral spacing between them in a radial direction. Each moveable conductive electrode track has a radial offset from a median line between adjacent fixed conductive electrode tracks such that each moveable conductive electrode track has a different lateral spacing from two different adjacent fixed conductive electrode tracks in opposite radial directions.

公开(公告)号：US10670623B2

公开(公告)日：2020-06-02

申请号：US15754293

申请日：2016-08-11

Applicant: Atlantic Inertial Systems Limited

Inventor： Kiran Mysore Harish ,  Alan Malvern

IPC: G01P15/125 ,  B81B3/00 ,  G01P15/08

Abstract: A capacitive accelerometer comprises: a substantially planar proof mass mounted to a fixed substrate by flexible support legs so as to be linearly moveable in an in-plane sensing direction. The proof mass comprises first and second sets of moveable capacitive electrode fingers. First and second sets of fixed capacitive electrode fingers interdigitates with the first and second sets of moveable electrode fingers respectively. A set of moveable damping fingers extend from the proof mass substantially perpendicular to the sensing direction, laterally spaced in the sensing direction. A set of fixed damping fingers mounted to the fixed substrate interdigitates with the set of moveable damping fingers and comprises an electrical connection to the proof mass so that the interdigitated damping fingers are electrically common. The damping fingers are mounted in a gaseous medium that provides a damping effect.

公开(公告)号：US11662361B2

公开(公告)日：2023-05-30

申请号：US17168698

申请日：2021-02-05

Applicant: Atlantic Inertial Systems Limited

Inventor： Christopher Paul Fell ,  Alan Malvern

IPC: G01P15/125 ,  G01D3/06 ,  G01L1/14 ,  G01P21/00

CPC classification number: G01P15/125 ,  B81B2201/033 ,  G01D3/066 ,  G01L1/144 ,  G01P21/00

Abstract: A capacitive accelerometer includes a proof mass, first and second fixed capacitive electrodes, and a DC biasing element arranged to apply a DC voltage (VB) to the proof mass based on a threshold acceleration value. A first closed loop circuit is arranged to detect a signal resulting from displacement of the proof mass and control the pulse width modulation signal generator to apply the first and second drive signals V1, V2 with a variable mark:space ratio. A second closed loop circuit keeps the mark:space ratio constant and to change the magnitude, VB, of the DC voltage applied to the proof mass by the DC biasing element so as to provide a net electrostatic restoring force on the proof mass for balancing the inertial force of the applied acceleration and maintaining the proof mass at a null position, when the applied acceleration is greater than a threshold acceleration value.

公开(公告)号：US20180217179A1

公开(公告)日：2018-08-02

申请号：US15754293

申请日：2016-08-11

Applicant: Atlantic Inertial Systems Limited

Inventor： Kiran Mysore Harish ,  Alan Malvern

IPC: G01P15/125 ,  B81B3/00

Abstract: A capacitive accelerometer comprises: a substantially planar proof mass mounted to a fixed substrate by flexible support legs so as to be linearly moveable in an in-plane sensing direction. The proof mass comprises first and second sets of moveable capacitive electrode fingers. First and second sets of fixed capacitive electrode fingers interdigitates with the first and second sets of moveable electrode fingers respectively. A set of moveable damping fingers extend from the proof mass substantially perpendicular to the sensing direction, laterally spaced in the sensing direction. A set of fixed damping fingers mounted to the fixed substrate interdigitates with the set of moveable damping fingers and comprises an electrical connection to the proof mass so that the interdigitated damping fingers are electrically common. The damping fingers are mounted in a gaseous medium that provides a damping effect.

公开(公告)号：US10900994B2

公开(公告)日：2021-01-26

申请号：US15782982

申请日：2017-10-13

Applicant: Atlantic Inertial Systems, Limited

Inventor： Alan Malvern

IPC: G01P15/11 ,  G01P15/08 ,  G01P15/125 ,  G01P15/13

Abstract: An accelerometer closed loop control system comprising: a capacitive accelerometer comprising a proof mass moveable relative to first and second fixed capacitor electrodes; a PWM generator to generate in-phase and anti-phase PWM drive signals with an adjustable mark/space ratio, wherein said drive signals are applied to the first and second electrodes such that they are charged alternately; an output signal detector to detect a pick-off signal from the accelerometer representing a displacement of the proof mass from a null position to provide an error signal, wherein the null position is the position of the proof mass relative to the fixed electrodes when no acceleration is applied; a PWM servo operating in closed loop to vary the mark/space ratio of said PWM drive signals in response to the error signal so that mechanical inertial forces are balanced by electrostatic forces.

公开(公告)号：US20200158751A1

公开(公告)日：2020-05-21

申请号：US16679509

申请日：2019-11-11

Applicant: Atlantic Inertial Systems Limited

Inventor： Alan Malvern

IPC: G01P15/125 ,  G01P15/08 ,  G01P15/13

Abstract: An accelerometer includes a planar proof mass mounted to a fixed substrate so as to be linearly moveable in an out-of-plane sensing direction in response to an applied acceleration. The proof mass includes first and second sets of moveable capacitive electrode fingers extending from the proof mass perpendicular to the sensing direction in a first in-plane direction and laterally spaced in a second in-plane direction perpendicular to the sensing direction. The moveable capacitive electrode fingers interdigitate with corresponding sets of fixed capacitive electrode fingers mounted to the substrate. The first set of fixed fingers has a thickness less than a thickness of the first set of moveable fingers; and wherein the second set of fixed fingers has a thickness greater than a thickness of the second set of moveable fingers.

公开(公告)号：US10274511B2

公开(公告)日：2019-04-30

申请号：US15107118

申请日：2014-12-11

Applicant: Atlantic Inertial Systems, Limited

Inventor： Alan Malvern

IPC: G01P15/125 ,  B81B5/00 ,  G01P15/13 ,  G01P15/08

Abstract: A capacitive accelerometer including: at least one additional fixed capacitor electrode with a plurality of additional fixed capacitive electrode fingers extending along the sensing direction. The proof mass comprises a plurality of moveable capacitive electrode fingers extending from the proof mass along the sensing direction and arranged to interdigitate with the plurality of additional fixed capacitive electrode fingers of the at least one additional fixed capacitor electrode. A means is provided for applying a voltage to the at least one additional fixed capacitor electrode to apply an electrostatic force to the plurality of moveable capacitive electrode fingers that acts to pull the proof mass towards the at least one further fixed capacitor electrode and thereby reduces the lateral spacings between the movable capacitive electrode fingers of the proof mass and the first and second sets of fixed capacitive electrode fingers that provide electrostatic forces for sensing purposes.

公开(公告)号：US09476907B2

公开(公告)日：2016-10-25

申请号：US14349942

申请日：2012-10-02

Applicant: Atlantic Inertial Systems Limited

Inventor： Alan Malvern ,  Louise Snell ,  Steven Westbury

IPC: G01P15/135 ,  G01P15/125 ,  G01P15/08

CPC classification number: G01P15/135 ,  G01P15/125 ,  G01P2015/0857

Abstract: An accelerometer comprises a support (12), a proof mass (14) supported for movement relative to the support (12) by a plurality of mounting legs (16), a plurality of fixed capacitor fingers associated with the support (12) and a plurality of movable capacitor fingers associated with the proof mass (14), the fixed capacitor fingers being interdigitated with the movable capacitor fingers, the mounting legs (16) being of serpentine shape, each mounting leg (16) comprising at least a first generally straight section (16a), a second generally straight section (16a), and an end section (16b) of generally U-shaped form interconnecting the first and second generally straight sections (16a), wherein the thickness Te of the end section (16b) is greater than the thickness Tc of a central part (16c) of both of the first and second generally straight sections (16a).

Abstract translation: 加速度计包括支撑件（12），支撑用于通过多个安装腿（16）相对于支撑件（12）运动的检测质量块（14），与支撑件（12）相关联的多个固定电容器手指和 与所述检测质量块（14）相关联的多个可移动电容器指状物，所述固定电容器指状物与所述可移动电容器指状物相互交错，所述安装腿（16）具有蛇形形状，每个安装腿部（16）至少包括第一大致直线 （16a），第二大致直线部分（16a）和大致U形形状的端部部分（16b），其互连第一和第二大致直线部分（16a），其中端部部分（16b）的厚度Te 大于第一和第二大致直的部分（16a）的中心部分（16c）的厚度Tc。

公开(公告)号：US11041724B2

公开(公告)日：2021-06-22

申请号：US15784255

申请日：2017-10-16

Applicant: Atlantic Inertial Systems, Limited

Inventor： Alan Malvern ,  Nicholas R. Wilkinson

IPC: G01C21/00 ,  G01C21/16 ,  G01C21/04

Abstract: A navigation system comprising: an inertial navigation system arranged to output a first position estimate; a terrain based navigation unit arranged to output a second position estimate; a gravity based navigation unit arranged to output a third position estimate; a stored gravity map arranged to receive a position and to output gravity information for that position; and an iterative algorithm unit arranged to determine an INS error state in each iteration; wherein in each iteration the iterative algorithm unit is arranged to: receive the first position estimate, the second position estimate, and the third position estimate; determine a gravity corrected position estimate based on the first position estimate, the INS error state and the gravity information; and update the INS error state for the next iteration based on the INS error state, the gravity corrected position estimate, the second position estimate and the third position estimate.