Abstract: A vibrating structure angular rate sensor comprises a substrate; a plurality of supporting structures fixed to the substrate; an annular member flexibly supported by the plurality of supporting structures 204; a drive system arranged to apply a periodic driving force such that the annular member 202 oscillates, in use, in a primary mode of vibration at a resonant frequency f1, with an amplitude of motion that generates a restoring force from the plurality of supporting structures 204; and a pick-off system arranged to determine the amplitude of motion of a secondary mode of vibration at a resonant frequency f2, in which oscillation of the annular member 202 is induced by the Coriolis force resulting from an angular rate experienced by the sensor 100. In use, the restoring force has a non-linear relationship with the amplitude of motion and a number p of supporting structures is selected such that f1=f2.

Abstract: A vibrating structure angular rate sensor comprises a substrate; a plurality of supporting structures fixed to the substrate; an annular member flexibly supported by the plurality of supporting structures 204; a drive system arranged to apply a periodic driving force such that the annular member 202 oscillates, in use, in a primary mode of vibration at a resonant frequency f1, with an amplitude of motion that generates a restoring force from the plurality of supporting structures 204; and a pick-off system arranged to determine the amplitude of motion of a secondary mode of vibration at a resonant frequency f2, in which oscillation of the annular member 202 is induced by the Coriolis force resulting from an angular rate experienced by the sensor 100. In use, the restoring force has a non-linear relationship with the amplitude of motion and a number p of supporting structures is selected such that f1=f2.

Abstract: A two axis gyroscope including a substantially planar vibratory resonator (5) having a substantially ring or hoop-like structure with inner and other peripheries extending around a common axis, carrier mode drive (22) for causing the resonator (5) to vibrate in a cosn? vibration mode, carrier mode pick-off (23) for sensing movement of the resonator (5) in response to the carrier mode drive (22), X-axis response mode pick-off (25) for detecting movement of the resonator in response to rotation about the X-axis, X-axis response mode drive (24) for nulling said motion, y-axis response mode pick-off (27) for detecting movement of the resonator in response to rotation about the y-axis, y-axis response mode drive (26) for nulling said motion, and a support (9) for flexibly supporting the resonator (5) and for allowing the resonator to vibrate relative to the support (9) in response to the carrier mode drive (22) and to applied rotation, wherein the support (9) comprises only L legs, where, when L is even: L=2N/K,

Abstract: A rate sensing device includes a cylindrical vibratory resonator, a hemispherical vibratory resonator or a substantially planar vibratory resonator (1) having a substantially ring or hoop-like shape structure, which resonators have inner and outer peripheries extending around a common axis (2), first carrier mode drive means (18) for causing the resonator (1) to vibrate in a Cos n1? carrier mode to provide a first rate sensing channel along the common axis (2), where n1 has an integer value of 2 or more, and second carrier mode drive means (19) for causing the resonator (1) to vibrate in a Cos n2? carrier mode to provide a second rate sensing channel along the common axis (2) where n2 has an integer value of 2 or more and where n2 is not equal to n1, which first and second rate sensing channels are independent of one another and operate over different rate ranges where the rate range increases for higher values of n1 and n2.

Abstract: A three axis rate sensor includes a substantially planar vibratory resonator having a substantially ring or hoop-like structure with inner and outer peripheries extending around a common axis, drive means for causing the resonator to vibrate in a Cos 2? vibration mode, carrier mode pick-off means for sensing movement of the resonator in response to the applied drive z-axis response mode, pick-off means for detecting movement of the resonator in response to rotation about the z-axis, z-axis response mode drive means for nulling said motion, x-axis response mode pick-off mean for detecting movement of the resonator in response to rotation about the x-axis, x-axis response mode drive means for nulling said motion, y-axis response mode pick-off mean for detecting movement of the resonator in response to rotation about the y-axis, y-axis response mode drive means for nulling said motion, and support means for flexibly supporting the resonator and for allowing the resonator to vibrate relative to the support means

Abstract: A three axis sensor including a substantially planar vibrator resonator or having a substantially ring or hoop like structure with inner and outer peripheries e tending around a common axis, drive means for causing the resonator to vibrate in an in lane cos 2? vibration mode, carrier mode pick-off means for sensing movement of the resonator in response to said drive means, pick-off means for sensing in plane sin 2? resonator motion induced by rotation about the z-axis, drive means for nulling said motion, pick-off means for sensing out of plane sin 3? resonator motion induced by rotation about the x-axis, drive means for nulling said motion, pick-off means for sensing out of plane cos 3? resonator motion induced by rotation about the y-axis, drive means for nulling said motion, and support means for flexibly supporting the resonator and for allowing the resonator to vibrate relative to the support means in response to the drive means and to applied rotations, wherein the support means comprises only L support

Abstract: A three axis rate sensor includes a substantially planar vibratory resonator (5) having a substantially ring or hoop-like structure with inner (6) and outer peripheries extending around a common axis, drive means (22) for causing the resonator to vibrate in a Cos 2&thgr; vibration mode, carrier mode pick-off means (23) for sensing movement of the resonator (5) in response to the applied drive means, x-axis, y-axis and z-axis response mode, pick-off means (25, 27, 31) for detecting movement of the resonator in response to rotation about the x-axis, y-axis and z-axis, x-axis, y-axis and z-axis response mode drive means (24, 26, 30) for nulling said motion and support means (9) for flexibly supporting the resonator and for allowing the resonator (5) to vibrate relative to the support means (9) in response to the drive means (22) and the applied rotation wherein the support means (9) comprises only L support beams, where L≠2 k, and k=0, 1, 2 or 3.

Abstract: A two axis gyroscope including a planar vibratory resonator (5) having a ring or hoop-like structure, carrier mode drive means (22) for causing the resonator (5) to vibrate in a cos n&thgr; vibration mode, carrier mode pick-off means (23) for sensing movement of the resonator (5), X-axis response mode pick-off means (25; 27) for detecting movement of the resonator in response to rotation about the x-axis and y-axis; x-axis and y-axis response mode drive means (24; 26) for nulling said motions and support means (9) for flexibly supporting the resonator (5) and for allowing the resonator to vibrate relative to the support means (9) in response to the drive means (22) and to applied rotation; wherein the support (9) means comprises only L legs, where, when L is even: L=2N/K, and where, when L is odd: L=N/K, where K is an integer, L>2 and N is the carrier mode order.

Abstract: A three axis sensor including a substantially planar vibrator resonator (2) having a substantially ring or hoop like structure, drive means (4) for causing the resonator (2) to vibrate in an in plane cos 2&thgr; vibration mode, carrier mode pick-off means (5) for sensing movement of the resonator in response to said drive means, pick-off means (6) for sensing in plane sin 2&thgr; resonator motion induced by rotation about the z-axis, drive means (7) for nulling said motion, pick-off means (8) for sensing out of plane sin 3&thgr; resonator motion induced by rotation about the x-axis, drive means (9) for nulling said motion, pick-off means (10) for sensing out of plane cos 3&thgr; resonator motion induced by rotation about the y-axis, drive means (11) for nulling said motion, and support means (9) for flexibly supporting the resonator, wherein the support means comprises only L support beams, where L≠2J×3K and J=0, 1 or 2 and K=0 or 1 with L>24.