JP5294142B2 - Vibration gyro sensor - Google Patents

Description

  The present invention relates to a vibration gyro sensor for detecting angular velocity.

  As one of angular velocity sensors, a vibration gyro sensor that detects an angular velocity by exciting a driving vibrator at a predetermined resonance frequency and detecting a Coriolis force generated by the influence of the angular velocity with a detection vibrator is widely used. As a structure of the vibration gyro sensor, for example, a tuning fork type gyro sensor (Patent Document 1), a cantilever gyro sensor (Patent Document 2), an H-type gyro sensor (Patent Document 3), and the like are known.

  There are sensitivity characteristics (amplitude) and response characteristics (response stability) as important characteristics for evaluating the sensor characteristics of the gyro sensor. The larger the amplitude of the vibrator, the better the sensitivity characteristic. Further, the shorter the time until the vibrator settles from an excessive state to a stable state, the better the response characteristics. When these sensor characteristics are evaluated by a parameter called a quality factor (Q value) of the vibrator, if the Q value is increased, the sensitivity increases, but the sensor characteristics have poor response characteristics. On the other hand, if the Q value is reduced, the response characteristic is improved, but the sensor characteristic is low in sensitivity. Here, the Q value is (energy stored by the vibrator) / (energy given to the vibrator in one cycle), and is a parameter serving as an index of the efficiency of the vibrator. As the loss of the vibrator increases, the Q value decreases.

In the prior art, a vibration gyro sensor is made by combining a drive vibrator material and a detection vibrator material different from each other, and combining a drive vibrator having a large Q value and a detection vibrator having a small Q value. What constitutes is known (Patent Document 4).
JP 2004-177367 A JP 2005-291858 A JP 2004-245605 A JP 2002-277247 A

  However, in the configuration described in Patent Document 4, it is difficult to accurately adjust the resonance frequency of the drive vibrator and the resonance frequency of the detection vibrator in order to join the vibrators made of different materials. In addition to the technical problem, there remains a technical problem that it is unclear whether or not micro vibration due to the Coriolis force is induced in the detection vibrator with a measurable amplitude.

  In view of the above problems, an object of the present invention is to provide a vibration gyro sensor excellent in sensitivity characteristics and response characteristics.

In order to solve the above problem, a vibration gyro sensor according to a first aspect of the present invention includes a drive vibrator and a detection vibrator formed from the same silicon substrate . Here, the drive vibrator is formed so that the Young's modulus in the crystal orientation of the silicon substrate in the direction parallel to the vibration direction of the drive vibrator is maximized, and the detection vibrator is parallel to the vibration direction of the detection vibrator. It is formed so that the Young's modulus in the crystal orientation of the silicon substrate in the direction is minimized.

The strongly related to the sensitivity characteristic is the Q _x of the driving oscillator, who Q _x is large vibration curvature increases. On the other hand, to relate to the response characteristics is Q _y of the detection vibrator, who Q _y is small response characteristics are improved. Here, by making the Young's modulus of the material in the direction parallel to the vibration direction of the detection vibrator smaller than the Young's modulus of the material in the direction parallel to the vibration direction of the drive vibrator, it is related to the sensitivity characteristics of the vibration gyro sensor. the Q _x of the drive vibrators while leaving its, it becomes possible to lower only the Q _y of the detection vibrator related to the response characteristics, while maintaining the sensitivity characteristic, it is possible to improve the response characteristics.

The vibration gyro sensor according to the second aspect of the present invention includes a first base connected to the drive vibrator, a second base connected to the detection vibrator, a first base, and a second base. And a support part for connecting the two. A connection portion between the detection vibrator and the second base is formed to be thinner than a connection portion between the drive vibrator and the first base. Thus, the operation of the detection vibrator is softer than the operation of the drive vibrator, without reducing the Q _x of the drive vibrator related to the sensitivity characteristics of the vibration gyro sensor, the detection vibrator related to the response characteristics it is possible to reduce the Q _y only, while maintaining the sensitivity characteristic, it is possible to improve the response characteristics.

  In the vibration gyro sensor according to the third aspect of the present invention, the detection vibrator includes a first detection vibration arm and a second detection vibration arm. The first detection vibration arm and the second detection vibration arm are formed so as to intersect at the second base portion. Thereby, the Young's modulus in the crystal orientation of the material in the direction parallel to the vibration direction of the first and second detection vibrating arms is smaller than the Young's modulus in the crystal orientation of the material in the direction parallel to the vibration direction of the drive vibrator. The first and second detection vibration arms can be formed in such a direction.

  According to the present invention, the response characteristic can be improved while maintaining the sensitivity characteristic of the vibration gyro sensor.

  In this embodiment, the sensor characteristic of the vibration gyro sensor is analyzed by a dynamic vibration model. The shape of the vibration gyro sensor to be analyzed is a tuning fork type or a cantilever beam that is widely used in general, but the basic concept can be widely applied to other shapes.

The operation of the vibration gyro sensor is divided into a drive vibration direction and a detection vibration direction perpendicular thereto, and is modeled as two coupled vibrators. Here, each vibrator is referred to as a drive vibrator and a detection vibrator. When each driving equation is described with the displacement of the drive vibrator as x and the displacement of the detection vibrator as y, the equations (F1) to (F2) are established.
^{md 2 x / dt 2 = -k} x x-2mα x dx / dt + Fe j ω t ... (F1)
^{md 2 y / dt 2 = -k} y y-2mα y dy / dt + γ ys x + 2mβ c dx / dt ... (F2)

Equation (F1) shows the equation of motion of the drive vibrator. The left side shows the mass × acceleration of the drive vibrator. m is the mass of the drive vibrator. The right side shows the force applied to the drive vibrator. Since the restoring force with respect to the displacement can be approximated as being generally proportional to the displacement if it is a minute displacement, the proportional constant is k _{x in} the first term on the right side. Further, as a loss term that gives a loss to the drive vibrator, a force proportional to the speed is taken into consideration, and in the second term on the right side, the proportionality constant is 2mα _x . The third term on the right side represents a sinusoidal vibration force having an amplitude F and an angular frequency ω.

Equation (F2) represents the equation of motion of the detection vibrator. The left side shows the mass × acceleration of the detection vibrator. m is the mass of the detection vibrator. The right side shows the force applied to the detection vibrator. The meanings of the first term and the second term on the right side are the same as the first term and the second term on the right side of the equation (1). However, since it is considered that there is a difference in restoring force and loss depending on the vibration direction depending on the material characteristics and shape, proportional constants k _y and 2mα _y different from those of the driving vibrator are used. The third term expresses a force proportional to the displacement x of the drive vibration as indicating mechanical coupling from the drive vibrator to the detection vibrator. γ _yx x indicates mechanical coupling from the drive vibrator to the detection vibrator. In the vibration gyro sensor, when rotation is applied, a Coriolis force proportional to the angular velocity β _c and the velocity of the vibrator works perpendicularly to the velocity. That is, the detection vibrator is driven by Coriolis force. In the fourth term on the right side, the proportionality constant of the force is 2 mβ _c , and the coupling between the drive vibrator and the detection vibrator due to the Coriolis force is expressed.

Here, when the quality factor of the driving vibrator is Q _x and the quality factor of the detection vibrator is Q _y , the equations (F3) to (F4) are established.
Q _x = ω _x / 2α _x = 1 / 2η _x = sqr (k _x / m) / 2α _x (F3)
_{Q y = ω y / 2α y} = R / 2η y = sqr (k y / m) / 2α y ... (F4)

Here, ω _x and ω _y are resonance frequencies of the drive vibrator and the detection vibrator when there is no friction (α _x = α _y = 0), respectively. α _x and α _y are proportional coefficients of loss terms proportional to the speeds of the drive vibrator and the detection vibrator, respectively. η _x and η _y are parameters indicating the magnitude of loss obtained by dividing the proportionality constant of the loss term by ω _x . R is a dimensionless amount indicating how much the resonance frequency of the drive vibrator and the detection vibrator is different, and R = ω _y / ω _x . The function sqr is a function whose return value is the square root of the argument.

Next, the relationship between the amplitude of the detection vibrator and Q _x and Q _y will be considered.
When a vibration gyro sensor with a small loss is operated at the resonance frequency ω _x of the drive vibrator, Expressions (F5) to (F6) are established, where the amplitude of the detection vibrator is ρ _y and the drive force is F.
ρ _y = FQ _x / mω _x ² [(R _m ⁴ + 4ε ² ) / {(R ² −1) ² + R ² / Q _y ² }] ^1/2 (F5)
R _m = (γ _yx / m) ^1/2 / ω _x (F6)

FIG. 1 is a graph obtained when Q _x is changed while keeping Q _y constant. In this graph, the horizontal axis represents the resonance frequency ratio R, and the vertical axis represents the amplitude ρ _y . As shown in this graph, it can be seen that the amplitude ρ _y of the detection vibrator decreases as Q _x decreases. FIG. 2 is a graph obtained when Q _y is changed while Q _x is constant. In this graph, the horizontal axis represents the resonance frequency ratio R, and the vertical axis represents the amplitude ρ _y . Since the solid line graph and the broken line graph overlap, only the solid line graph is displayed in the drawing. As shown in this graph, it can be seen that the amplitude ρ _y of the detection vibrator is hardly influenced by a decrease in Q _y . To summarize the above considerations, it has been found that the amplitude ρ _y of the detection vibrator decreases as Q _x of the drive vibrator decreases, but is not affected by Q _{y of the} detection vibrator.

Next, the relationship between the response characteristics of the detection vibrator and Q _x and Q _y will be considered.
The time constant τ _y representing the response characteristic of the detection vibrator can be described as an equation (F7) that does not depend on Q _x .
τ _y = 1 / α _y = 1 / ω _x η _y = 2Q _y / ω _y = R / ω _y η _y (F7)

FIGS. 3 to 4 show the transient response of the amplitude ρ _y when the stepped angular velocity is input to the vibration gyro sensor and the detected vibration is detected at the timing when the drive vibration becomes maximum. Figure 3 shows the transient response when the Q _y = 5300, FIG. 4 shows the transient response when the Q _y = 110. 3 to 4, the horizontal axis represents time, and the vertical axis represents normalized amplitude. As can be seen from these figures, the excessive response shown in FIG. 4 where Q _y is relatively smaller by an order of magnitude is faster than the transient response shown in FIG. . To summarize the above considerations, it has been found that the response characteristic of the detection vibrator improves as Q _y is reduced.

From the above analysis results, the following conclusions can be drawn with respect to the sensor characteristics of the vibration gyro sensor.
(1) to strongly related to the sensitivity characteristic is the Q _x of the driving oscillator, who Q _x is large vibration amplitude is increased.
(2) it is to relate to the response characteristics, a Q _y of the detection vibrator, who Q _y is small response characteristics are improved.

The above conclusion is that the operation of the vibration gyro sensor is divided into a drive vibration direction and a detection vibration direction perpendicular to the drive vibration direction, and is modeled as two coupled vibrators, and the amplitude and response characteristics of the detection vibrator and Q _x and Q _y are modeled. It was obtained for the first time by the inventor's analysis method of considering the relationship between the Applying the above conclusion, the sensitivity is maintained if Q _x of the drive vibrator related to the sensitivity characteristic of the vibration gyro sensor is left as it is, and only Q _{y of the} detection vibrator related to the response characteristic is lowered. As a result, the response characteristics can be improved. Such an approach can be applied not only to a normal tuning fork type, cantilever type or H type vibration gyro sensor, but in principle to any shape or structure of a vibration gyro sensor. Of course, the present invention can also be applied to a vibration gyro sensor in which both the drive vibrator and the detection vibrator are made of the same material.

Then, the Q _x of the drive vibrator related to sensitivity characteristics intact, consider the method of reducing only the Q _y of the detection vibrator related to the response characteristic.

As a first method, a method of increasing α _y can be considered. When the detection vibrator is modeled into an electric circuit and considered, α _y is electrically equivalent to a direct current resistance, and therefore α _y can be increased by increasing the resistance value of the detection vibrator. For example, (1) the electrode width of the detection vibrator is made narrower than the electrode width of the drive vibrator, (2) the electrode film thickness of the detection vibrator is made thinner than the electrode film thickness of the detection vibrator, and (3) the detection vibration. A conductive oxide having a relatively high electrical resistance (for example, RuO ₂ , TrO ₂ , RhO ₂ , TiO, LaO, ReO ₃ , SrRio ₃ , Sr ₂ RuO ₄ , CaRuO ₃ , LaTiO ₃ , LaNiO ₃ ) ₃ , Ln ₂ O ₃ , SnO ₂ , ZnO), and a metal material (Cu, Au, Pt, Cr, Ti, Ni, Al) having a relatively low electric resistance is used as an electrode of the drive vibrator. A method is conceivable.

Since α _y is a proportional coefficient of braking force proportional to speed and corresponds to loss, it can be changed by external factors such as friction with surrounding air (viscous fluid). Specifically, (4) the detection vibrator is flattened, or a wing or the like is attached to the detection vibrator to increase the air resistance of the detection vibrator, (5) a material that absorbs the detection vibration (for example, resin Or a mechanism for attaching the mechanism to the detection vibrator.

As a second method, a method of reducing the k _y are contemplated. k _y is a proportional coefficient of the restoring force with respect to the displacement of the detection vibrator, and is equivalent to the Young's modulus (or spring constant). Specifically, (6) the crystal orientation is taken so that the restoring force of the detection vibrator becomes weak (a crystal orientation with a small Young's modulus), and (7) the detection vibration is made so that the operation of the detection vibrator becomes soft. A method of putting a groove or notch in the root of the child is conceivable.

A third method is to reduce the resonance frequency ratio R. This method, after all, is equivalent to the method for reducing the similarly k _y and the second method. However, when the drive vibrator and the detection vibrator have different shapes, the resonance frequency ratio R can be reduced by increasing the mass m of the detection vibrator.

According to the present embodiment, the roles of the drive vibrator Q _x and the detection vibrator Q _y are clarified, and the drive vibrator Q _x related to the sensitivity characteristic is left as it is, and the detection vibration related to the response characteristic is maintained. by lowering only the Q _y the child, while maintaining the sensitivity characteristic, the response characteristic can be further improved. As is apparent from the analysis results of FIG. 2, since there is no variation in amplitude by a change in Q _y, Q _y is a small value is preferably as much as possible, specifically preferably 100 or less. For example, _if both Q _x and Q _y are increased without distinguishing the roles of the drive vibrator Q _x and the detection vibrator Q _y , a vibration gyro sensor having a slow response characteristic is obtained although the sensitivity is large. On the other hand, if Q _x and Q _y are both small, the response speed is fast but the vibration gyro sensor has low sensitivity.

  Embodiment 1 according to the present invention will be described below with reference to the drawings. The members having the same reference numerals indicate the same members, and redundant description is omitted. The drawings are schematic, and for convenience of explanation, the relationship between the thickness and the planar dimensions and the ratio of the thickness of each layer are different from those of an actual vibration gyro sensor.

FIG. 5 is a plan view of the vibration gyro sensor 10 according to the first embodiment.
In the figure, the right direction of the drawing is the X direction, the upper direction of the drawing is the Y direction, and the direction perpendicular to the drawing is the Z direction. The vibration gyro sensor 10 includes a plurality of drive vibration arms 14A, 14B, 14C, and 14D, a plurality of detection vibration arms 15A, 15B, 15C, and 15D, a plurality of base portions 11, 13A, and 13B, and a plurality of support portions 12A, 12B. A pair of support portions 12A and 12B protrude from the base portion 11. A pair of drive vibration arms 14A and 14B are formed from the base portion 13A located at the tip of the support portion 12A in a direction orthogonal to the support portion 12A. Similarly, a pair of drive vibration arms 14C and 14D are formed in a direction orthogonal to the support portion 12B from the base portion 13B located at the tip of the support portion 12B. In the base 11, the first pair of detection vibration arms 15A and 15B and the second pair of detection vibration arms 15C and 15D intersect each other at an acute angle (180 ° −θ1−θ3 or 180 ° −θ2−θ4). It is formed to do. A total of four drive vibration arms 14A, 14B, 14C, and 14D, and a total of four detection vibration arms 15A, 15B, 15C, and 15D vibrate in the XY plane.

  The drive vibration arms 14A, 14B, 14C, and 14D correspond to the “drive vibrator” in the above-described dynamic vibration model, and the detection vibration arms 15A, 15B, 15C, and 15D are the above-described dynamic vibration models. Corresponds to the “detection transducer” in FIG.

  A drive piezoelectric element for exciting the drive vibration arm 14A is formed at the base of the connection of the drive vibration arm 14A to the base 13A. Similarly, for the other drive vibration arms 14B, 14C, and 14D, a drive piezoelectric element is formed at a connection root portion with respect to the base portion 13A or 13B. In addition, a detection piezoelectric element for detecting detection vibration excited by the detection vibration arm 15A is formed at the base of connection of the detection vibration arm 15A to the base 11. Similarly, the other detection vibration arms 15B, 15C, and 15D have detection piezoelectric elements formed at the connection roots with respect to the base 11. In the vibration gyro sensor 10, a drive signal (AC signal) is supplied to the drive piezoelectric element to excite the drive vibration arms 14A, 14B, 14C, and 14D, and the vibration gyro sensor 10 is rotated in this state while detecting the vibration arm. An angular velocity signal output is obtained by detecting the detection vibration excited by 15A, 15B, 15C, and 15D by the detection piezoelectric element.

  The above-mentioned base parts 11, 13A, 13B, support parts 12A, 12B, drive vibration arms 14A, 14B, 14C, 14D, and detection vibration arms 15A, 15B, 15C, 15D have an appropriate mechanical strength and are fine. It is integrally formed by etching a material suitable for processing. As such a material, for example, a silicon substrate is suitable. As shown in FIG. 6, the Young's modulus of the silicon substrate having the plane orientation (100) has an orientation period of 90 °. The Young's moduli of the crystal orientations <100>, <010>, <-100>, and <001> are all the same and also the minimum value. On the other hand, the Young's moduli of the crystal orientations <110>, <−110>, <1-10>, and <011> are all the same and are maximum values. In general, the Young's modulus is a constant that determines the value of strain with respect to stress within a predetermined elastic range, and has a value specific to the material according to the crystal orientation.

K _y described in the equation (F2) is a proportional coefficient of the restoring force with respect to the displacement of the detection vibration arms 15A, 15B, 15C, and 15D, and is equivalent to the Young's modulus (or spring constant). When the vibration gyro sensor 10 is rotated while exciting the drive vibration arms 14A, 14B, 14C, and 14D, the detection vibration arms 15A, 15B, and 15B are detected more than the restoring force that acts on the drive vibration arms 14A, 14B, 14C, and 14D. Select a combination of the vibration direction and crystal orientation of each of the drive vibration arms 14A, 14B, 14C, 14D and the detection vibration arms 15A, 15B, 15C, 15D so that the restoring force acting on 15C, 15D becomes weaker Thus, while maintaining the sensitivity characteristic by maintaining Q _x of the drive vibrator related to the sensitivity characteristic of the vibration gyro sensor 10 as it is and reducing only Q _{y of the} detection vibrator related to the response characteristic, Response characteristics can be further improved.

  As a preferred specific example of the present embodiment, driving is performed so that the vibration direction P of the drive vibration arms 14A, 14B, 14C, and 14D is parallel to the crystal orientation (for example, <011>) having the maximum Young's modulus. The direction of the vibrating arms 14A, 14B, 14C, 14D is adjusted. On the other hand, the detection vibration arms 15A and 15B and the support portions 12A and 12B are arranged so that the vibration direction Q1 of the detection vibration arms 15A and 15B and the crystal orientation (for example, <001>) having the minimum Young's modulus are parallel to each other. The formed angles θ1 and θ2 are adjusted. For the other pair of detection vibration arms 15C and 15D, the detection vibration arms 15C and 15D and the holding portion are arranged so that the vibration direction Q2 thereof is parallel to the crystal orientation (for example, <010>) having the minimum Young's modulus. Angles θ3 and θ4 formed by 12A and 12B are adjusted. When the combinations of the vibration directions and crystal orientations of the drive vibration arms 14A, 14B, 14C, and 14D and the detection vibration arms 15A, 15B, 15C, and 15D are adjusted as described above, the angles θ1, θ2, θ3, and θ4 are obtained. , Respectively 45 °.

  The present invention is not limited to the above-described preferred specific example, and the detection vibration arms 15A, 15B are more than the Young's modulus of the crystal orientation parallel to the vibration direction of the drive vibration arms 14A, 14B, 14C, 14D. , 15C, 15D so that the Young's modulus of the crystal orientation parallel to the vibration direction of each of the drive vibration arms 14A, 14B, 14C, 14D and the detection vibration arms 15A, 15B, 15C, 15D is relatively small. A combination of the vibration direction and the crystal orientation may be selected. For example, the crystal orientation parallel to the vibration direction of the drive vibration arms 14A, 14B, 14C, and 14D may be an orientation slightly shifted from the crystal orientation having the maximum Young's modulus by a predetermined angle. In this case, the crystal orientation parallel to the vibration direction of the detection vibration arms 15A, 15B, 15C, and 15D is adjusted to a crystal orientation having a Young's modulus smaller than the Young's modulus of the orientation shifted by a predetermined angle. The material of the vibration gyro sensor 10 is not limited to the silicon substrate, and any material having a different Young's modulus depending on the crystal orientation can be used.

FIG. 7 is a plan view of the vibration gyro sensor 20 according to the second embodiment.
The members having the same reference numerals as those shown in FIG. 5 indicate the same members, the detailed description thereof will be omitted, and differences between the second embodiment and the first embodiment will be described in detail. In the second embodiment, the connection base portions 17A, 17B of the detection vibration arms 15A, 15B, 15C, 15D are connected to the connection base portions 16A, 16B, 16C, 16D of the drive vibration arms 14A, 14B, 14C, 14D, respectively. , 17C, 17D are processed so as to be thinner (the width of the arm is narrower). Since stress due to vibration acts on these connection root portions 16A, 16B, 16C, 16D, 17A, 17B, 17C, and 17D in a concentrated manner, the connection root portions 16A, 16B, 16C, and 16D are connected to each other. By making the portions 17A, 17B, 17C, and 17D thinner, the spring constants of the detection vibration arms 15A, 15B, 15C, and 15D become smaller than the spring constants of the drive vibration arms 14A, 14B, 14C, and 14D, and the operation is flexible. Become. The spring constant by adjusting in this manner, without reducing the Q _x of the drive vibrator related to the sensitivity characteristics of the vibration gyro sensor 20, is possible to reduce only the Q _y of the detection vibrator related to the response characteristics it can. Accordingly, the sensitivity characteristics of the vibration gyro sensor 20 are maintained in combination with the relationship between the vibration direction and the crystal orientation of each of the drive vibration arms 14A, 14B, 14C, 14D and the detection vibration arms 15A, 15B, 15C, 15D. However, the response characteristics can be further improved. The structure of the above-described vibration gyro sensors 10 and 20 can also be applied to a vibration gyro vibrator including a “drive vibrator” and a “detection vibrator”.

It is a graph which shows the sensitivity characteristic of a detection vibrator. It is a graph which shows the sensitivity characteristic of a detection vibrator. It is a graph which shows the response characteristic of a detection vibrator. It is a graph which shows the response characteristic of a detection vibrator. 1 is a plan view of a vibration gyro sensor according to Embodiment 1. FIG. It is a graph which shows the relationship between the crystal orientation of a silicon | silicone, and Young's modulus. 6 is a plan view of a vibration gyro sensor according to Embodiment 2. FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10,20 ... Vibration gyro sensor 11, 13A, 13B ... Base part 12A, 12B ... Support part 14A, 14B, 14C, 14D ... Drive vibration arm 15A, 15B, 15C, 15D ... Detection vibration arm 16A, 16B, 16C, 16D, 17A, 17B, 17C, 17D ... Connection root

Claims (6)

A vibratory gyro vibrator comprising a drive vibrator and a detection vibrator formed from the same silicon substrate ,
The drive vibrator is formed such that the Young's modulus in the crystal orientation of the silicon substrate in a direction parallel to the vibration direction of the drive vibrator is maximized,
The detection vibrator is a vibration gyro vibrator formed such that a Young's modulus in a crystal orientation of the silicon substrate in a direction parallel to a vibration direction of the detection vibrator is minimized . The vibrating gyro vibrator according to claim 1 ,
A first base connected to the drive vibrator;
A second base connected to the detection transducer;
A support portion connecting the first base portion and the second base portion;
The vibration gyro vibrator is configured such that a connection portion between the detection vibrator and the second base is formed narrower than a connection portion between the drive vibrator and the first base. A vibrating gyro vibrator according to claim 2 ,
The detection vibrator includes a first detection vibration arm and a second detection vibration arm,
The first detection vibration arm and the second detection vibration arm are vibration gyro vibrators formed so as to intersect at the second base portion. A vibration gyro sensor comprising a drive vibrator and a detection vibrator formed from the same silicon substrate ,
The drive vibrator is formed such that the Young's modulus in the crystal orientation of the silicon substrate in a direction parallel to the vibration direction of the drive vibrator is maximized,
The detection vibrator is a vibration gyro sensor formed so that a Young's modulus in a crystal orientation of the silicon substrate in a direction parallel to a vibration direction of the detection vibrator is minimized . The vibration gyro sensor according to claim 4 ,
A first base connected to the drive vibrator;
A second base connected to the detection transducer;
A support portion connecting the first base portion and the second base portion;
A vibration gyro sensor in which a connection portion between the detection vibrator and the second base is formed narrower than a connection portion between the drive vibrator and the first base. The vibration gyro sensor according to claim 5 ,
The detection vibrator includes a first detection vibration arm and a second detection vibration arm,
The vibration gyro sensor, wherein the first detection vibration arm and the second detection vibration arm are formed so as to intersect at the second base.

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