Vibratory gyroscope

• US 20050028591A1
• Filed: 09/11/2002
• Published: 02/10/2005
• Est. Priority Date: 09/11/2001
• Status: Active Grant

• Current Assignee: Transense Technologies Plc
• Original Assignee: Transense Technologies Plc
• Inventors: Lonsdale, Anthony, Lonsdale, Bryan
• Granted Patent: US 6,959,600 B2
• Time in Patent Office: Days
• US Class Current: 73/504.120
• CPC Class Codes: G01C 19/5698 using acoustic waves, e.g. surface acoustic wave gyros

Abstract

A vibratory gyroscope is provided that includes a vibratory element; a vibration inducing device for inducing a mode of vibration into the vibratory element; and a processing device for generating, in response to a change in strain detected in the vibratory element, a signal indicative of a rate of rotation about an axis of the vibratory element corresponding to a rotation imparted to the vibratory element subsequent to an inducing of the vibration. The vibration inducing device includes an acoustic signal source provided at a location spaced from the vibratory element. Undesirable effects associated with mounting the vibration inducing device to the vibratory element are thereby avoided.

Claims

1. A vibratory gyroscopes, comprising:

a vibratory element;

means for inducing a mode of vibration into said vibratory element, said inducing means including an acoustic signal source provided at a location spaced from said vibratory element;

means for detecting strain in said vibratory element;

processing means for generating, in response to a change in strain detected in said vibratory element, a signal indicative of a rate of rotation about an axis of said vibratory element corresponding to a rotation imparted to said vibratory element subsequent to an inducing of said vibration; and

dampening means for reducing to zero said change in strain, said dampening means including an acoustic signal source.

2. The vibratory gyroscope as claimed in claim 1, wherein the acoustic signal source of said dampening means is provided at a location spaced from said vibratory element.

3. The vibratory gyroscope as claimed in claim 1, wherein said means for detecting strain comprises a Surface Acoustic Wave (SAW) device mounted to said vibratory element and in electrical communication with said processing means by a capacitive or inductive couple.

4. The vibratory gyroscope as claimed in claim 1, wherein said means for detecting strain comprises:

a first capacitor plate mounted to a portion of said vibratory element which moves, during vibration of said element, relative to a fixture; and

a second capacitor plate mounted to said fixture adjacent the first capacitor plate.

5. A The vibratory gyroscope as claimed in claim 1, wherein said means for detecting strain comprises an interferometer that, in turn, includes means for reflecting light from a portion of said vibratory element which moves, during vibration of said element, relative to a fixture.

12. The vibratory gyroscope as claimed in claim 2, wherein said means for detecting strain comprises a Surface Acoustic Wave (SAW) device mounted to said vibratory element and in electrical communication with said processing means by a capacitive or inductive couple.

13. The vibratory gyroscope as claimed in claim 2, wherein said means for detecting strain comprises:

a first capacitor plate mounted to a portion of said vibratory element which moves, during vibration of said element, relative to a fixture; and

a second capacitor plate mounted to said fixture adjacent the first capacitor plate.

14. The vibratory gyroscope as claimed in claim 2, wherein said means for detecting strain comprises an interferometer that, in turn, includes means for reflecting light from a portion of said vibratory element which moves, during vibration of said element, relative to a fixture.

15. The vibratory gyroscope as claimed in claim 14, wherein said interferometer comprises a laser.

6. The vibratory gyroscope as claimed in claim 54, wherein said interferometer comprises a laser.

7. A vibratory gyroscopes comprising:

a vibratory element;

means for inducing a mode of vibration into said vibratory element;

means for detecting strain in said vibratory element; and

processing means for generating, in response to a change in strain detected in said vibratory element, a signal indicative of a rate of rotation about an axis of said vibratory element corresponding to a rotation imparted to said vibratory element subsequent to an inducing of said vibration,

wherein said means for detecting strain comprises a Surface Acoustic Wave (SAW) device mounted to said vibratory element and in electrical communication with said processing means by a capacitive or inductive couple.

16. The vibratory gyroscope as claimed in claim 7, wherein said means for inducing a mode of vibration comprises an acoustic signal source provided at a location spaced from said vibratory element.

8. A vibratory gyroscope, comprising

a vibratory element;

means for inducing a mode of vibration into said vibratory element;

means for detecting strain in said vibratory element; and

processing means for generating, in response to a change in strain detected in said vibratory element, a signal indicative of a rate of rotation about an axis of said vibratory element corresponding to a rotation imparted to said vibratory element subsequent to an inducing of said vibration,

wherein said means for detecting strain comprises;

a first capacitor plate mounted to a portion of said vibratory element which moves, during vibration of said element, relative to a fixture; and

a second capacitor plate mounted to said fixture adjacent the first capacitor plate.

17. The vibratory gyroscope as claimed in claim 8, wherein said means for inducing a mode of vibration comprises an acoustic signal source provided at a location spaced from said vibratory element.

9. A vibratory gyroscope, comprising

a vibratory element;

means for inducing a mode of vibration into said vibratory element;

means for detecting strain in said vibratory element; and

processing means for generating, in response to a change in strain detected in said vibratory element, a signal indicative of a rate of rotation about an axis of said vibratory element wherein said corresponding to a rotation is that imparted to said vibratory element subsequent to an inducing of said vibration, and

wherein said means for detecting strain comprises an interferometer that, in turn, includes means for reflecting light from a portion of said vibratory element which moves, during vibration of said element, relative to a fixture.

10. The vibratory gyroscope as claimed in claim 9, wherein said interferometer comprises a laser.

11. The vibratory gyroscope as claimed in claims 9, wherein said means for inducing a mode of vibration comprises an acoustic signal source provided at a location spaced from said vibratory element.