US 5,668,318 AGranted

Angular velocity sensor

AssigneeWacoh Corporation

InventorKazuhiro Okada

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Abstract

An angular velocity sensor for detecting angular velocity components about three axes with high response is provided. A weight body carries out a circular movement along a circular orbit within the XY-plane with the origin being as a center. The weight body is supported so that it can be moved with a predetermined degree of freedom within a sensor casing. A Coriolis force Fco exerted in the Z-axis direction to the weight body is detected when the weight body passes through the X-axis at the point Px and an angular velocity .omega.x about the X-axis is obtained based on the detected force. Further, a Coriolis force Fco exerted in the Z-axis direction to the weight body is detected when the weight body passes through the Y-axis at the point Py and an angular velocity .omega.y about the Y-axis is obtained based on the detected force. In addition, a force exerted in the X-axis direction to the weight body at the point Px is detected and an angular velocity .omega.z about the Z-axis is obtained based on the detected force by eliminating a centrifugal force.

Claims14

Dependent claims

An angular velocity sensor comprising:

a weight body having mass;
a sensor casing for accommodating the weight body therewithin;
supporting means for supporting the weight body so that the weight body can be moved with a predetermined degree of freedom with respect to the sensor casing;
driving means for allowing the weight body to carry out an orbital movement along a predetermined orbit within a range of said predetermined degree of freedom;
detecting means for detecting a Coriolis force applied to the weight body in a first axial direction perpendicular to a tangential direction of the orbital movement;
and
operation means for obtaining an angular velocity about a second axis perpendicular to both the tangential direction and the first axial direction on the basis of a tangential velocity of the weight body along said orbit and the detected Coriolis force;
wherein an XYZ three-dimensional coordinate system having an X-axis, a Y-axis and a Z-axis is defined and the weight body is positioned at an origin of the coordinate system;
wherein the driving means comprises a first force generator for applying a force to the weight body in a positive direction of the X-axis, a second force generator for applying a force to the weight body in a positive direction of the Y-axis, a third force generator for applying a force to the weight body in a negative direction of the X-axis, and a fourth generator for applying a force to the weight body in a negative direction of the Y-axis;
and
wherein said first to fourth force generators are periodically operated so that the weight body carries out an orbital movement within an XY-plane.

8 more elements

An angular velocity sensor comprising:

a weight body having mass;
a sensor casing for accommodating the weight body therewithin;
supporting means for supporting the weight body so that the weight body can be moved with a predetermined degree of freedom with respect to the sensor casing;
driving means for allowing the weight body to carry out an orbital movement along a predetermined orbit within a range of said predetermined degree of freedom;
detecting means for detecting a Coriolis force applied to the weight body in a first axial direction perpendicular to a tangential direction of the orbital movement;
and
operation means for obtaining an angular velocity about a second axis perpendicular to both the tangential direction and the first axial direction on the basis of a tangential velocity of the weight body along said orbit and the detected Coriolis force;
wherein the supporting means comprises a flexible substrate having flexibility, a peripheral portion of said flexible substrate being fixed to the sensor casing and the weight body being fixed at a central portion of said flexible substrate,
wherein the driving means comprises a plurality of force generators for applying a force in a predetermined direction at a predetermined portion of the flexible substrate, said force generators being disposed on the flexible substrate;
and
wherein the detecting means comprises a plurality of displacement detectors for detecting a displacement in a predetermined direction of a predetermined portion of the flexible substrate, said detecting means being disposed on the flexible substrate.

8 more elements

Dependencies are inferred from the claim text.

Facts

Application: 08/601,794Filed 15 Feb 1996
Priority: JP 7-05669021 Feb 1995
Granted: 16 Sep 1997
Term ends: Not estimatedThe source records don’t support an estimate.

Classification6 codes

G01C 19/56
Gyroscopes; Turn-sensitive devices using vibrating masses; Turn-sensitive devices without moving masses; Measuring angular rate using gyroscopic…:…
G01P 3/44
Devices characterised by the use of electric or magnetic means: for measuring angular speed
G01P 15/18
Measuring acceleration; Measuring deceleration; Measuring shock, i.e. sudden change of acceleration: in two or more dimensions
G01P 2015/084
For defining out-of-plane movement of the mass: the mass being suspended at more than one of its sides, e.g. membrane-type suspension, so as to…