Abstract: Specimens for evaluating corrosion protection of substrates due, at least in part, to coatings applied thereupon are described. A specimen (1) comprises: a first coating (10), comprising a first set of layers (11) including a first layer (11A), on a first substrate (12); and a first set of perforations (100), including a first perforation (100A) and a second perforation (100B), in the first coating (10), wherein the first perforation (100A) has a first depth D1 through the first coating (10) and a first dimension W1 transverse to the first depth, wherein the second perforation (100B) has a second depth D2 through the first coating (10) and a second dimension transverse to the second depth D2 and wherein the first dimension W1 and the second dimension W2 are different.

Abstract: A vibratory ring structure is described which comprises a ring body and at least one ring electrode secured thereto, the or each ring electrode extending over a first angular extent and: being attached to the ring body over second angular extent, wherein the first angular extent is greater than the second angular extent.

Abstract: A method of reactive ion etching a substrate 46 to form at least a first and a second etched feature (42, 44) is disclosed. The first etched feature (42) has a greater aspect ratio (depth:width) than the second etched feature (44). In a first etching stage the substrate (46) is etched so as to etch only said first feature (42) to a predetermined depth. Thereafter in a second etching stage, the substrate (46) is etched so as to etch both said first and said second features (42, 44) to a respective depth. A mask (40) may be applied to define apertures corresponding in shape to the features (42, 44). The region of the substrate (46) in which the second etched feature (44) is to be produced is selectively masked with a second maskant (50) during the first etching stage, The second maskant (50) is then removed prior to the second etching stage.

Abstract: A vibratory ring structure is described which comprises a ring body and at least one ring electrode secured thereto, the or each ring electrode extending over a first angular extent and: being attached to the ring body over second angular extent, wherein the first angular extent is greater than the second angular extent.

Abstract: A method of reactive ion etching a substrate 46 to form at least a first and a second etched feature (42, 44) is disclosed. The first etched feature (42) has a greater aspect ratio (depth:width) than the second etched feature (44). In a first etching stage the substrate (46) is etched so as to etch only said first feature (42) to a predetermined depth. Thereafter in a second etching stage, the substrate (46) is etched so as to etch both said first and said second features (42, 44) to a respective depth. A mask (40) may be applied to define apertures corresponding in shape to the features (42, 44). The region of the substrate (46) in which the second etched feature (44) is to be produced is selectively masked with a second maskant (50) during the first etching stage, The second maskant (50) is then removed prior to the second etching stage.

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 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.

Abstract: A single axis rate sensor (10) including a substantially planar vibratory resonator (16) having a substantially ring or hoop-like structure with inner (24) and outer peripheries extending around a common axis, drive means (18) for causing the resonator to vibrate in a Cos&thgr; vibration mode, carrier mode pick-off means (20) for sensing movement of the resonator in response to said drive means (18), pick-off means (36) for sensing resonator movement induced in response to rotation of the rate sensor about the sensitive axis, drive means (38) for mulling said motion, and support means (22) for flexibly supporting the resonator (16) and for allowing the resonator (16) to vibrate relative to the support means (22) in response to the drive means, and to applied rotation wherein the support means (16) comprises only L support beams, where L≠3×2K−1, L>2 and K=1, 2 or 3.

Abstract: A single axis rate sensor including a substantially planar vibratory resonator (1) having a substantially ring or hoop-like structure with inner and outer peripheries (1a, 1b) extending around a common axis (z) drive means (6) for causing the resonator (1) to vibrate in a Cos 2&thgr; vibration mode, carrier mode pick-off means (7) for sensing movement of the resonator (1) in response to said drive means pick-off means (9) for detecting Sin 2&thgr; vibration mode motion induced by rotation around the Z-axis, Sin 2&thgr; vibration mode drive means (8) for nulling said motion and support means (2) for flexibly supporting the resonator (1) and for allowing the resonator (1) to vibrate relative to the support means (2) in response to the drive means, or to applied rotation wherein the support means comprises only L support beams, where L≠2K, and K=0, 1,2 or 3.