Micromachined inertial angle sensor

Abstract

The present application relates to an angle sensor, further comprising: at least one vibratory mass (8) which can be moved relative to the support (6); and at least one electrostatic adjustment transducer (Q +) configured to apply an adjustable electrostatic strength to the vibratory mass (8), the or each electrostatic adjustment transducer (Q +) comprising at least two rows of teeth (20A, 20B) forming a pair of combs. The angle sensor further comprises at least one intermediate structure (18) which is elongated in at least one direction of extension (26), said intermediate structure (18) protruding from the attachment edge (28, 30) of the vibrating mass (8) or the support (6) and supporting one of the rows of teeth.

Description

[0001] The present application relates to a micromachined inertial angular sensor.

[0002] The present application relates to the field of using inertial angular sensors on vehicles. Such sensors are used for, for example, navigation, driving, guidance or pathfinding.

[0003] Inertial angular sensors are configured to measure angular position and are then generally referred to as gyroscopes. In another case, angular sensors are configured to measure angular velocity, and in this case, they are called gyrometers.

[0004] Micromachined inertial angular sensors, also known as MEMS inertial sensors, are known per se, for example see EP2960625A1.

[0005] Such sensors generally include one or more masses that are excited to vibrate in a plane formed by mutually perpendicular X and Y axes. This plane is perpendicular to the Z axis, which forms the so-called sensitive axis of the sensor. When the sensor rotates about its sensitive axis, the combination of the vibration of the moving mass and the angular rotation vector generates a force due to the Coriolis effect, causing the moving mass to vibrate naturally perpendicular to the excitation vibration and the sensitive axis. The amplitude of this natural vibration is proportional to the rotation speed of the sensor, and the value of the angular velocity about the sensitive axis can be derived.

[0006] For example, inertial angular sensors have mechanical deviations due to manufacturing tolerances. To improve the measurement accuracy of such sensors, adjustment actuators can be provided to compensate or balance these mechanical deviations, such as mass or shape deviations of the sensor or certain parts of the sensor.

[0007] In one example, mechanical deviations or defects in a micromachined sensor cause cross-axis bias. Cross-axis bias corresponds to the coupling of forces acting on the vibrating mass of the micromachined sensor along two perpendicular axes. To compensate for this cross-axis bias, one or more electrostatic transducers must be provided to apply a force to compensate for the cross-axis bias. However, such adjustment transducers typically occupy a large amount of space on the surface of the micromachined sensor. Also, an increase in the force applied by these electrostatic transducers generally means an increase in the size of the transducers.

[0008] Given the limited surface area of micromachined inertial angular sensors, it is difficult to provide electrostatic transducers, especially for cross-axis bias compensation, that have a high applicable force for compensation.

[0009] An object of the present application is to overcome the above disadvantages.

[0010] Therefore, an object of the present application is to obtain a micromachined inertial angular sensor that can compensate for mechanical deviations even in the presence of strong bias while reducing the size of the sensor.

[0011] To this end, the object of the present application is to provide a micromachined inertial angular sensor, comprising: a support having a first axis in a support plane and a second axis perpendicular to the first axis and contained in the support plane, the angular sensor further comprising: at least one vibrating mass that can move relative to the support; at least one excitation transducer configured to generate a vibrating motion of the vibrating mass; and at least one transducer for detecting the vibration of the vibrating mass.

[0012] The angular sensor comprises: at least one electrostatic adjustment transducer configured to apply an adjustable electrostatic strength to the vibrating mass. The or each electrostatic adjustment transducer comprises at least two rows of teeth forming a pair of combs.

[0013] Wherein the angular sensor further comprises: at least one intermediate structure that is elongated in at least one extension direction, the intermediate structure protruding from an attachment edge of the vibrating mass or the support and carrying one row of teeth. The or each intermediate structure comprises a plurality of portions that extend in their respective extension directions in a plane parallel to or coinciding with the support plane, and the extension directions of two consecutive portions are preferably perpendicular to each other.

[0014] The angular sensor comprises: at least one elongated intermediate structure that increases the surface area or edge length available for arranging the rows of teeth within the sensor without increasing the total surface area required for the electrostatic adjustment transducer. The rows of teeth of the transducer, for example, are not directly arranged on the attachment edge of the vibrating mass or the support, but are carried by an elongated intermediate structure that has a larger surface area for attaching these rows of teeth.

[0015] Therefore, due to the angular sensor described in the present application, in particular, rows of teeth with a large number of teeth are arranged on the elongated intermediate structure. As a result, the force applied by the sensor is increased without increasing the surface area occupied by the sensor.

[0016] In other advantageous aspects of the present application, the angular sensor comprises one or more of the following features, which can be employed individually or in any technically possible combination:

[0017] - Each row of teeth comprises a plurality of teeth extending parallel to each other, each tooth in the row of teeth being carried by the intermediate structure and protruding from the intermediate structure, preferably in a direction perpendicular to the extension direction of the intermediate structure;

[0018] - The said or each adjustment transducer is an electrostatic transducer for compensating for orthogonal bias, which is configured to change the intensity distribution acting on the vibrating mass member, and the orthogonal bias corresponds to the coupling of the intensities acting on the vibrating mass member along the first axis and the second axis;

[0019] - An angle of 45 - 90 degrees is formed between the extending direction of the said or each intermediate structure and the attachment edge;

[0020] - The said angle is approximately equal to 90 degrees;

[0021] - The said angular sensor comprises: a plurality of intermediate structures parallel to each other;

[0022] - The said two rows of teeth comprise: a first row of teeth integral with the vibrating mass member, and a second row of teeth integral with the support member; when the intermediate structure carries the first row of teeth, it projects from the attachment edge of the vibrating mass member, which attachment edge is also referred to as the movable edge; when the intermediate structure carries the second row of teeth, it projects from the attachment edge of the support member, which attachment edge is also referred to as the fixed edge;

[0023] - The said angular sensor comprises: at least one intermediate structure projecting from the movable edge and carrying the first row of teeth, and at least one intermediate structure projecting from the fixed edge and carrying the second row of teeth;

[0024] - The said or each intermediate structure comprises a plurality of portions, which portions extend in their respective extending directions in a plane parallel to or coinciding with the support plane;

[0025] - The extending directions of two consecutive portions are perpendicular to each other;

[0026] - The said or each intermediate structure and at least one row of the said rows of teeth form a fractal structure, wherein the said row of teeth is provided with a row of secondary teeth projecting from the teeth of the said row of teeth;

[0027] - At least the said or each intermediate structure and the row of teeth carried by the intermediate structure are formed of a single component;

[0028] - The said angular sensor comprises: at least two vibrating mass members, which are movable relative to the support member and relative to each other, are suspended from fixed anchor points on the support member by suspension springs, and are coupled together by coupling springs for in - phase vibration.

[0029] These features and advantages of the present application will become apparent after reading the following description, which is given only by way of non - limiting examples and with reference to the accompanying drawings, wherein:

[0030] - Figure 1 Figure 1 ​Schematic diagram of an inertial angle sensor instance of the present application;

[0031] - Figure 2 Figure 2 is Figure 1 Schematic diagram of an instance of a part of an angle sensor, which according to the present application includes an intermediate structure and an adjustment transducer;

[0032] - Figure 3 Figure 3 is another instance according to the present application, a schematic diagram similar to Figure 2 ;

[0033] - Figure 4 Figure 4 is another instance according to the present application, a schematic diagram similar to Figure 2-3 ;

[0034] - Figure 5 Figure 5 is another instance according to the present application, a schematic diagram similar to Figure 2-4 ;

[0035] Referring to Figure 1 , the angle sensor 2 includes: a support 6, which extends along a first axis X and a second axis Y perpendicular to the first axis X in a support plane.

[0036] Hereinafter, the microfabricated inertial angle sensor 2 will be referred to as the angle sensor 2.

[0037] The angle sensor 2 is, for example, a gyro tester configured to measure angular velocity. Alternatively or additionally, the angle sensor 2 is a gyroscope for measuring angular position.

[0038] The angle sensor 2 is a microfabricated sensor and thus forms a microelectromechanical system, which is also defined by its abbreviation MEMS.

[0039] Specifically, the angle sensor 2 is a sensor designed to be mounted on a vehicle (not shown), for example, an aircraft, a drone or a ship.

[0040] The angle sensor 2 is, for example, designed to be used in a navigation, maneuvering or guidance system of a vehicle.

[0041] The angle sensor includes at least one vibrating mass.

[0042] Referring to Figure 1 , the angle sensor 2 includes, for example, two vibrating masses 8, 10 arranged around each other to form a so-called inner mass 8 and an outer mass 10.

[0043] ​​​​Specifically, the angular sensor 2 is a tuning fork gyroscope, and more specifically, a tuning fork gyroscope having two vibrating mass elements.

[0044] "Vibrating mass element" means that the said or each mass element 8, 10 can oscillate, which oscillation is driven, for example, in the manner described below, and also driven by the Coriolis effect when the angular sensor 2 rotates.

[0045] Each vibrating mass element 8, 10 can move relative to the support 6.

[0046] In the case where there are two vibrating mass elements 8, 10, the vibrating mass elements 8, 10 also preferably can move relative to each other. Specifically, when in a stationary state, the centers of gravity 0 of the vibrating mass elements 8, 10 coincide.

[0047] The angular sensor 2 further includes, for example, suspension springs 12, for example, four are provided for each vibrating mass element 8, 10 to suspend each vibrating mass element 8, 10 from its respective anchor point 14, which anchor point 14 is fixed relative to the support 6.

[0048] The angular sensor 2 further includes, for example, coupling springs 16. For example, when the angular sensor 2 includes two mass elements 8, 10, four coupling springs are provided, and these coupling springs couple the vibrating mass elements 8, 10 to each other to allow the mass elements 8, 10 to vibrate in antiphase.

[0049] Reference Figure 2-5 shows that the angular sensor 2 includes at least one intermediate structure 18 protruding from the vibrating mass element 8, 10 or the support 6. Figure 2-5 The examples in show the intermediate structure 18 protruding from the vibrating mass element 8 and the intermediate structure 18 protruding from the support 6. In addition, although not shown, the angular sensor 2 further includes an intermediate structure 18 protruding from the vibrating mass element 10.

[0050] Reference Figure 1 shows that the angular sensor 2 further includes at least one detection transducer Dx, Dy, which is configured to detect the vibration of the vibrating mass elements 8, 10. Each detection transducer Dx, Dy includes, for example, at least one comb integrated with the vibrating mass elements 8, 10 and at least one comb integrated with the support 6. In this case, each detection transducer Dx, Dy is thus configured to detect the vibration by measuring the load change between the combs.

[0051] The angular sensor 2 further includes at least one excitation transducer Ex, Ey, which is configured to generate the vibration motion of the vibrating mass elements 8, 10.

[0052] The angular sensor 2 further includes at least one electrostatic adjustment transducer Tx, Ty, Q+, Q-.

[0053] In Figure 1 In the illustrated example, only the detection transducers Dx, Dy, the excitation transducers Ex, Ey, and the electrostatic adjustment transducers Tx, Ty, Q+, Q- provided on the inner mass member 8 are shown. Preferably, the angular sensor 2 further includes detection transducers Dx, Dy, excitation transducers Ex, Ey, and / or electrostatic adjustment transducers Tx, Ty, Q+, Q- provided on the outer mass member 10.

[0054] For example, each of the electrostatic adjustment transducers Tx, Ty, Q+, Q- is configured to apply an adjustable electrostatic strength to the vibrating mass members 8, 10.

[0055] "Adjustable electrostatic strength" means that the corresponding electrostatic adjustment transducer is configured to apply a force to the vibrating mass members 8, 10, for example, according to the received voltage.

[0056] In one example, the angular sensor 2 includes first-class electrostatic transducers Tx, Ty and second-class electrostatic transducers Q+, Q-.

[0057] The first-class electrostatic adjustment transducers Tx, Ty are configured to, for example, apply an electrostatic strength along the first axis X and / or along the second axis Y to compensate for the frequency deviation of the tuning fork vibration mode. Specifically, the first-class electrostatic adjustment transducers Tx, Ty are configured to compensate for the vibration frequency difference between the vibration along the first axis X and the vibration along the second axis Y.

[0058] Figure 1 An example of the first-class electrostatic adjustment transducers Tx, Ty is shown.

[0059] The first-class electrostatic adjustment transducers Tx, Ty include, for example, interleaved teeth, which specifically extend along the first axis X or along the second axis Y.

[0060] Specifically, the second-class electrostatic adjustment transducers Q+, Q- are configured to compensate for the quadrature bias.

[0061] The quadrature bias corresponds to the coupling of one or more strengths acting on the vibrating mass members 8, 10, and specifically corresponds to the coupling of the strengths of the suspension springs 12 along the first axis X and the second axis Y. For example, the quadrature bias is caused by differences in the manufacture of the suspension springs 12. An operating example of the second-class electrostatic adjustment transducers Q+, Q- is described in EP2960625A1.

[0062] Specifically, the second type of electrostatic adjustment transducers Q+, Q- are configured to modify the intensity distribution acting on the vibrating masses 8, 10, specifically in order to align the principal axis of the dynamic intensity with the first axis X and the second axis Y. Specifically, by adjusting the electrostatic intensity applied to the vibrating masses 8, 10, the second type of electrostatic adjustment transducers Q+, Q- are configured to compensate for the quadrature offset, for example, the quadrature offset caused by the manufacturing tolerances of the angular sensor 2.

[0063] Examples of the electrostatic transducers Tx, Ty, Q+, Q- and their arrangement in the angular sensor 2 will be described below. For the second type of Q+, Q- electrostatic transducers, they are also hereinafter referred to as electrostatic transducers Q+, Q-. However, those skilled in the art will understand that the arrangement of the electrostatic transducers Q+, Q- is equally applicable to the first type of Tx, Ty transducers as an alternative.

[0064] An example of the electrostatic adjustment transducers Q+, Q- is shown in Figure 2-5 which shows a partial structure of the angular sensor 2 including the electrostatic transducers Q+, Q-.

[0065] Each electrostatic transducer Q+, Q- includes at least two rows of teeth 20A, 20B that form a pair of combs, specifically a pair of interleaved combs. Each row of teeth 20A, 20B includes a plurality of teeth 22A, 22B that extend parallel to each other and are preferably composed of these teeth.

[0066] "Interleaved combs" specifically means that the teeth 22A, 22B are parallel to each other so as to apply or receive electrostatic forces respectively.

[0067] At least one row of teeth 20A, 20B is carried by the corresponding intermediate structure 18 of the angular sensor 2.

[0068] Specifically, each tooth 22A in the row of teeth 20A forms a pair of teeth with the corresponding tooth 22B in the row of teeth 20B. The teeth 22A and 22B in each pair of teeth are arranged substantially parallel to each other, and specifically, the distance therebetween is less than the minimum distance between other teeth 22A and 22B. Specifically, the teeth 22A, 22B in each pair of teeth are configured to apply an electrostatic force relative to each other.

[0069] For example, the two rows of teeth 20A, 20B include: a first row of teeth 20A attached to the vibrating masses 8, 10, and a second row of teeth 20B attached to the support 6.

[0070] For example, referring to Figure 2-3 , the teeth 22A are integral with the vibrating masses 8, 10, and the teeth 22B are integral with the support 6, and the teeth are carried by the corresponding intermediate structure 18.

[0071] Figure 2Shows an example of a part of the angular sensor 2, which includes an intermediate structure 18 carrying the toothed rows 20A, 20B of the electrostatic transducer Q+, and these toothed rows form a positive quadrature bias compensated electrostatic transducer.

[0072] "Positive quadrature bias" specifically refers to the fact that the force coupling acting on the vibrating mass members 8, 10 is a positive value.

[0073] Preferably, "positive quadrature bias" means that the movement of the vibrating mass members 8, 10 along the second axis Y generates a force along the first axis X, which is proportional to the movement along the second axis Y and has the same sign.

[0074] Figure 3 Shows an example of a part of the angular sensor 2, which includes an intermediate structure 18 carrying the toothed rows 20A, 20B of the electrostatic transducer Q-, and these toothed rows form a negative quadrature bias compensated electrostatic transducer.

[0075] "Negative quadrature bias" specifically refers to the fact that the force coupling acting on the vibrating mass members 8, 10 is a negative value.

[0076] Preferably, "negative quadrature bias" means that the movement of the vibrating mass members 8, 10 along the second axis Y generates a force along the first axis X, which is proportional to the movement along the second axis Y and has a different sign.

[0077] In the following, it will be combined with Figure 2-5 The intermediate structure 18 will be described in more detail.

[0078] Preferably, the angular sensor 2 includes a plurality of intermediate structures 18 arranged parallel to each other. Alternatively, the angular sensor 2 includes a single intermediate structure 18.

[0079] Each intermediate structure 18 extends at least along a corresponding extension direction 26.

[0080] Specifically, "extends at least along a corresponding extension direction 26" means that the intermediate structure 18 has a geometric shape, and the width perpendicular to the extension direction 26 is strictly less than the length of the intermediate structure 18 along the extension direction 26.

[0081] For example, the width is strictly less than half of the length, preferably strictly less than one-third of the length.

[0082] Specifically, each intermediate structure 18 has a rectangular shape extending along the extension direction 26, where the length of the edge parallel to the extension direction 26 is strictly greater than the length of the edge perpendicular to the extension direction 26.

[0083] Each intermediate structure 18 projects from the attachment edge 28 of the vibrating mass members 8, 10 or from the attachment edge 30 of the support member 6.

[0084] Specifically, each intermediate structure 18 projects from the respective attachment edges 28, 30 in an extended plane.

[0085] The extended plane is parallel to or coincides with the support plane.

[0086] Specifically, each attachment edge 28, 30 extends within the extended plane.

[0087] For example, an angle of 45° to 90° is formed between the extending direction 26 of the intermediate structure 18 and the attachment edges 28, 30. Preferably, the angle is approximately equal to 90°, that is, in the extended plane, the intermediate structure 18 projects from the respective attachment edges 28, 30 in a direction perpendicular to the edges 28, 30.

[0088] Each intermediate structure 18 carries rows of teeth 20A, 20B.

[0089] Reference Figure 2-3 , each tooth 22A in the row of teeth 20A forms a corresponding pair of teeth with the corresponding tooth 22B in the row of teeth 20B. In Figure 2 the illustrated example, along the extending direction 26 of each intermediate structure 18, the support member 6 projects, and each pair of teeth first includes the tooth 22B carried by this intermediate structure 18, and then includes the tooth 22A carried by the corresponding intermediate structure 18 and projecting from the vibrating mass member 8. In Figure 3 the illustrated example, the arrangement of the teeth 22A, 22B of each pair of teeth is opposite. This arrangement order of the teeth 22A, 22B of each pair of teeth can especially compensate for the corresponding orthogonal bias, that is, the positive orthogonal bias relative to the Figure 2 example, and the negative orthogonal bias relative to the Figure 3 example.

[0090] For example, each tooth 22A, 22B projects from the respective intermediate structure 18 in a direction perpendicular to the extending direction 26 of this intermediate structure 18. For example, each tooth 22A, 22B extends along a direction parallel to the attachment edges 28, 30, and the intermediate structure 18 projects from this attachment edge. Specifically, each tooth 22A, 22B projects from an edge of the respective intermediate structure 18 that is parallel to the extending direction 26 of the intermediate structure 18.

[0091] Preferably, when the intermediate structure 18 carries the first row of teeth 20A, it projects from the attachment edge 28 (also referred to as the movable edge) of the vibrating mass members 8, 10. Specifically, this intermediate structure 18 connects the first row of teeth 20A to the vibrating mass members 8, 10.

[0092] Even more preferably, when the intermediate structure 18 carries the second row of teeth 20B, the attachment edge 30 (also referred to as the fixed edge) of its self-supporting member 6 projects. Specifically, the intermediate structure 18 connects the second row of teeth 20B to the support member 6.

[0093] In one example, the angular sensor 2 includes one or more intermediate structures 18 that project from a movable edge and carry the first row of teeth 20A, and also includes one or more intermediate structures 18 that project from a fixed edge and carry the second row of teeth 20B.

[0094] Reference Figure 2 and Figure 3 , the angular sensor 2 includes, for example, a plurality of intermediate structures 2 that project from the attachment edge 30 of the support member 6 in different cross-sections, specifically perpendicular and / or parallel to each other, and / or includes several intermediate structures 2 that project from the attachment edge 28 of the corresponding vibrating mass members 8, 10 in different cross-sections, such as perpendicular and / or parallel to each other.

[0095] Reference Figure 4 and Figure 5 , the intermediate structure 18 or each intermediate structure 18 includes, for example, a plurality of portions S1, S2, S3, S4, S5, and optionally S6, S7. In this case, each of the portions S1 to S7 extends along its respective extension direction 26 in an extension plane. Specifically, along the corresponding extension direction 26, the extension directions 26 of two consecutive portions S1 to S7 show an angle perpendicular to each other.

[0096] For example, referring to Figure 4 , along the extension direction 26 of each intermediate structure 18 extending from the attachment edge 30 of the support member 6, the included angle between the extension directions 26 of the portions S1 to S7 of the intermediate structure 18 or each intermediate structure 18 is as follows: a counterclockwise 90° angle between portions S1 and S2, two clockwise 90° angles between portions S2 and S3 and between portions S3 and S4, two counterclockwise 90° angles between portions S4 and S5 and between portions S5 and S6, and a clockwise 90° angle between portions S6 and S7.

[0097] The teeth 22A are carried by at least two of the portions S1 to S7, here by portions S1 to S3, and similarly, the teeth 22B are also carried by at least two of the portions S1 to S7, here by portions S1 to S3. In this way, the teeth 22A, 22B carried by the same intermediate structure 18 are not parallel to each other. Advantageously, and not shown, the teeth 22A, 22B extend beyond each portion of the intermediate structure 18 that carries them.

[0098] In one example, referring toFigure 5 The extending directions 26 of two consecutive portions S1 to S5 are at 90° angles to each other in the counterclockwise direction. Specifically, the said or each intermediate structure 18 is substantially in a snail shape.

[0099] According to an example not shown, the said or each intermediate structure 18 and rows of teeth 20A, 20B form a fractal structure.

[0100] For example, rows of teeth 20A, 20B are equipped with secondary rows of teeth not shown in the figure. The secondary rows of teeth project from the teeth 22A, 22B of the rows of teeth 20A, 20B that provide the secondary rows of teeth. Thus, the teeth 22A, 22B constitute the intermediate structure of the secondary rows of teeth. The secondary teeth carried by the tooth 22A are subsequently configured to apply an electrostatic force to the secondary teeth carried by the tooth 22B, and conversely, the secondary teeth carried by the tooth 22B are configured to apply an electrostatic force to the secondary teeth carried by the tooth 22A, which is similar to the manner described for the rows of teeth 20A and 20B.

[0101] The secondary teeth, which are closer together than the primary teeth, are mainly responsible for generating the electrostatic force, while the force exerted by the primary teeth contributes only a small amount to the resultant force.

[0102] Advantageously, the arrangement of the secondary teeth is such that the teeth 22A and 22B and the secondary teeth are all arranged to compensate for positive orthogonal bias, or, conversely, such that the teeth 22A and 22B and the secondary teeth are all arranged to compensate for negative orthogonal bias.

[0103] Preferably, the secondary rows of teeth include secondary teeth that project from the teeth 22A, 22B in a secondary direction perpendicular to the extending direction of the teeth 22A, 22B. Specifically, the said secondary direction is parallel to the extending direction 26 of the intermediate structure 18 that carries the teeth 22A, 22B. The presence of the secondary teeth enables further increasing the number of teeth on the transducers Q+ and Q- without increasing the surface area occupied by the transducers Q+ or Q-.

[0104] Preferably, the intermediate structure 18 and the rows of teeth 20A, 20B supported by the intermediate structure 18 are formed from a single component.

[0105] Similarly, in the example, when the said or each intermediate structure 18 and rows of teeth 20A, 20B form a fractal structure, the intermediate structure 18, the rows of teeth 20A, 20B carried by the intermediate structure 18, and the secondary teeth carried by the rows of teeth 20A, 20B are all formed from a single component.

[0106] For example, when the intermediate structure 18 protrudes from the attachment edges 28 of the vibrating masses 8, 10, the vibrating masses 8, 10, the intermediate structure 18, and the teeth 22A carried by the intermediate structure 18 are formed from a single part. In another example, when the intermediate structure 18 is attached to the attachment edge 30 of the support 6, the support 6, the intermediate structure 18, and the teeth 22B are formed from a single part.

[0107] For example, an element formed from a single part is an element obtained by engraving or machining.

[0108] According to one example, at least one of the following elements, preferably all of the following elements, comprises silicon or consists of silicon: the support 6, the intermediate structure 18, the vibrating masses 8, 10, and the teeth 22A, 22B of each row of teeth 20A, 20B.

[0109] Obviously, the sensor 2 used in the present application has a number of advantages.

[0110] Specifically, the sensor 2 according to the present application comprises an intermediate structure 18 such that it is possible to increase the space available for arranging the large number of teeth 22A, 22B of each row of teeth 20A, 20B carried by the corresponding intermediate structure 18. In a number of variations and modifications of the sensor 2, electrostatic transducers Tx, Ty, Q+, Q- are involved to increase the electrostatic strength applied by them. By arranging a larger number of teeth on the intermediate structure 18, mechanical deviations can be compensated reliably and effectively. For example, this allows mechanical deviations to be compensated without increasing the electrical voltage of the transducers.

Claims

1. A micromachined inertial angular sensor (2), comprising: a support (6) having a first axis (X) in a support plane and a second axis (Y) perpendicular to the first axis (X) and contained in the support plane, the angular sensor (2) further comprising: at least one vibrating mass (8, 10) movable relative to the support (6); at least one excitation transducer (Ex, Ey) configured to generate a vibrating motion of the vibrating mass (8, 10); and at least one transducer (Dx, Dy) for detecting the vibration of the vibrating mass (8, 10), The angular sensor (2) comprises: at least one electrostatic adjustment transducer (Tx, Ty, Q+, Q-) configured to apply an adjustable electrostatic intensity to the vibrating mass (8, 10), the or each electrostatic adjustment transducer (Tx, Ty, Q+, Q-) comprising at least two rows of teeth (20A, 20B) forming a pair of combs, wherein the angular sensor (2) further comprises: at least one intermediate structure (18) elongated in at least one extension direction (26), the intermediate structure (18) protruding from an attachment edge (28, 30) of the vibrating mass (8, 10) or the support (6) and carrying one row of teeth (20A, 20B), wherein the or each intermediate structure (18) comprises a plurality of portions (S1, S2, S3, S4, S5, S6, S7) extending in a plane parallel to or coinciding with the support plane along their respective extension directions (26), and the extension directions (26) of two consecutive portions (S1, S2, S3, S4, S5, S6, S7) preferably have an angle perpendicular to each other.

2. The angular sensor (2) according to claim 1, wherein each row of teeth (20A, 20B) comprises a plurality of teeth (22A, 22B) extending parallel to each other, each tooth (22A, 22B) in the row of teeth (20A, 20B) being carried by the intermediate structure (18) and protruding from the intermediate structure (18), preferably in a direction perpendicular to the extension direction (26) of the intermediate structure (18).

3. The angular sensor (2) according to claim 1 or 2, wherein the or each adjustment transducer (Q+, Q-) is an electrostatic transducer (Q+, Q-) for compensating for cross-axis bias and is configured to change the intensity distribution acting on the vibrating mass (8, 10), the cross-axis bias corresponding to the coupling of the intensities acting on the vibrating mass (8, 10) along the first axis (X) and the second axis (Y).

4. The angular sensor (2) according to any one of the preceding claims, wherein an angle of 45 - 90 degrees is formed between the extension direction (26) of the or each intermediate structure (18) and the attachment edge, the angle preferably being approximately equal to 90 degrees.

5. The angular sensor (2) according to any one of the preceding claims, comprising: a plurality of intermediate structures (18) parallel to each other.

6. The angular sensor (2) according to any one of the preceding claims, wherein the two rows of teeth (20A, 20B) comprise: a first row of teeth (20A) integral with the vibrating mass members (8, 10), and a second row of teeth (20B) integral with the support member (6); wherein when the intermediate structure (18) carries the first row of teeth (20A), it projects from the attachment edge (28) of the vibrating mass members (8, 10), which attachment edge (28) is also referred to as the movable edge; wherein when the intermediate structure (18) carries the second row of teeth (20B), it projects from the attachment edge (30) of the support member (6), which attachment edge (30) is also referred to as the fixed edge.

7. The angular sensor (2) according to claim 6 in combination with claim 5, comprising: at least one intermediate structure (18) projecting from the movable edge and carrying the first row of teeth (20A), and at least one intermediate structure (18) projecting from the fixed edge and carrying the second row of teeth (20B).

8. The angular sensor (2) according to any one of the preceding claims, wherein the or each intermediate structure (18) and at least one of the rows of teeth (20A, 20B) form a fractal structure, wherein the rows of teeth (20A, 20B) are provided with rows of secondary teeth projecting from the teeth (22A, 22B) of the rows of teeth (20A, 20B).

9. The angular sensor (2) according to any one of the preceding claims, wherein at least the or each intermediate structure (18) and the rows of teeth (20A, 20B) carried by the intermediate structure (18) are formed from a single piece.

10. The angular sensor (2) according to any one of the preceding claims, comprising: at least two vibrating mass members (8, 10) movable relative to the support member (6) and relative to each other, suspended from fixed anchor points (14) on the support member (6) by suspension springs (12) and coupled together by a coupling spring (16) for anti-phase vibration.

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