WO2017159429A1 - Gyroscopic apparatus and method for controlling gyroscopic apparatus - Google Patents

Abstract

A gyroscopic apparatus provided with: a single two-dimensional oscillator driven by a drive signal corresponding to a first rotary oscillation mode and a drive signal corresponding to a second rotary oscillation mode; a first detector for detecting, from a signal outputted from the two-dimensional oscillator, the amplitude and phase of a component that corresponds to the first rotary oscillation mode; and a second detector for detecting, from a signal outputted from the two-dimensional oscillator, the amplitude and phase of a component that corresponds to the second rotary oscillation mode.

Description

Gyro apparatus and control method of gyro apparatus

The present invention relates to a gyro device and a method for controlling the gyro device. For example, the gyro device and the gyro device using a two-dimensional vibrator having a single (one) mode match (matching resonance frequencies of two orthogonal axes). It relates to a control method.

Conventionally, a gyro device for detecting the angular velocity of rotation has been proposed. For example, the following document (Non-Patent Document 1) uses two resonators, each of which is clockwise (CW (ClockwiseCrotation)) and counterclockwise (CCW (Counter-Clockwise rotation)). The gyro device is described in which the input angular velocity is obtained from the frequency difference between the resonators. Patent Document 1 below describes a device for exciting a ring-shaped vibrating gyroscope with clockwise and counterclockwise rotational vibrations.

JP-A-6-241810

However, the gyro device described in Non-Patent Document 1 has a problem that the characteristics of the two vibrators to be used must be completely the same. Further, since two vibrators are used, there is a problem that it is difficult to reduce the size of the apparatus. Furthermore, since the characteristics of the resonator, such as the resonance frequency and Q value, change as the temperature changes, it is necessary to match the usage conditions such as the ambient temperature of the two resonators in order to make the characteristics of the two resonators the same. There is a problem that there is. Further, Patent Document 1 does not disclose a specific configuration for detecting a CW or CCW mode component from the output of a vibrating gyroscope.

One of the objects of the present invention is to provide a novel and useful gyro apparatus and a control method for the gyro apparatus for solving these problems.

In order to solve the above-described problems, the present invention provides a driving signal corresponding to a first rotational vibration mode (for example, clockwise (CW) vibration mode) and a second rotational vibration mode (for example, counterclockwise (CCW) vibration). First detection for detecting the amplitude and phase of the component corresponding to the first rotational vibration mode from the single two-dimensional vibrator driven by the drive signal corresponding to the mode) and the signal output from the two-dimensional vibrator. And a second detector for detecting the amplitude and phase of the component corresponding to the second rotational vibration mode from the signal output from the two-dimensional vibrator.

In another aspect of the present invention, a single two-dimensional vibrator is driven by a drive signal corresponding to the first rotational vibration mode and a drive signal corresponding to the second rotational vibration mode, and a signal output from the two-dimensional vibrator. The gyro apparatus controls the amplitude and phase of the component corresponding to the first rotational vibration mode and detects the amplitude and phase of the component corresponding to the second rotational vibration mode from the signal output from the two-dimensional vibrator. Is the method.

According to the present invention, since a configuration using a single vibrator is employed, the apparatus can be miniaturized. In addition, since it is not necessary to use a plurality of vibrators, there is no variation in performance among vibrators, and the performance of the gyro device can be improved. It should be noted that the contents of the present invention are not construed as being limited by the effects exemplified in this specification.

FIG. 1 is a diagram for explaining an example of vibration in a ring-type resonator. FIG. 2 is a diagram for explaining an example of vibration in the ring-type resonator. FIG. 3 is a diagram for explaining a general synchronous detection method. FIG. 4 is a diagram for explaining a configuration and a method for detecting a CW mode component and a CCW mode component from an input signal. FIG. 5 is a diagram for explaining in detail a configuration and method for detecting a CW mode component and a CCW mode component from an input signal. FIG. 6 is a diagram for explaining an example of an output when detection is performed with a predetermined reference signal. FIG. 7 is a diagram for explaining another example of output when detection is performed with a predetermined reference signal. FIG. 8 is a diagram for explaining another example of output when detection is performed with a predetermined reference signal. FIG. 9 is a diagram for explaining another example of output when detection is performed with a predetermined reference signal. FIG. 10 is a diagram illustrating a configuration example of the gyro apparatus according to the embodiment of the present invention. FIG. 11 is a diagram illustrating a configuration example of the first detection unit according to the embodiment of the present invention. FIG. 12 is a diagram illustrating a configuration example of the second detection unit according to the embodiment of the present invention. FIG. 13 is a diagram schematically showing a signal flow in the gyro apparatus according to the embodiment of the present invention. FIG. 14 is a diagram illustrating a configuration example of the angular velocity detection unit according to the first embodiment of the present invention. FIG. 15A and FIG. 15B are diagrams for explaining the hole angle mode. 16A and 16B are diagrams illustrating a configuration example of an angle detection unit according to the second embodiment of the present invention. 17A and 17B are diagrams for explaining ideal vibration with respect to the drive signal. 18A and 18B are diagrams for explaining that, in an ideal vibration, the amplitude in the X direction and the amplitude in the Y direction coincide with each other at the resonance frequency, and the phase difference is 90 °. FIG. 19A and FIG. 19B are diagrams for explaining a problem caused by incompleteness of the vibrator. 20A and 20B are diagrams for explaining a problem caused by imperfection of a vibrator. FIG. 21 is a diagram for explaining a problem caused by imperfection of the vibrator. 22A and 22B are diagrams for explaining a method for solving a problem caused by imperfection of a vibrator. FIG. 23 is a diagram for explaining a problem caused by incompleteness of the vibrator. FIG. 24A and FIG. 24B are diagrams for explaining a problem caused by imperfections of the vibrator. FIG. 25A and FIG. 25B are diagrams for explaining a method for solving the problem caused by the imperfection of the vibrator. FIG. 26 is a block diagram illustrating a configuration example of the gyro device according to the third embodiment. FIG. 27A and FIG. 27B are diagrams for explaining the effects obtained by the third embodiment. FIG. 28A and FIG. 28B are diagrams for explaining the effects obtained by the third embodiment.

Hereinafter, embodiments and the like of the present invention will be described with reference to the drawings. The description will be given in the following order.
<1. First Embodiment>
<2. Second Embodiment>
<3. Third Embodiment>
<4. Modification>
The embodiments described below are suitable specific examples of the present invention, and the contents of the present invention are not limited to these embodiments.

<1. First Embodiment>
"General gyro equipment"
In order to facilitate understanding of the present invention, a general gyro apparatus (gyroscope) will be described. In the following description, a small vibration gyro apparatus using MEMS (Micro Electro Mechanical Systems) will be described as an example. In the gyro device, a process of detecting an angular velocity of rotation (hereinafter appropriately referred to as a rotational angular velocity) and integrating the rotational angular velocity to obtain a rotation angle (hereinafter appropriately referred to as a rotational angle) is performed. As a method of detecting the rotational angular velocity Omega _z, it is known several methods. As a first method, a method called AM (Amplitude Modulation) mode is known. In the AM mode, the angular velocity is obtained by measuring the amplitude (displacement) in the sense axis (eg, Y axis) direction that changes due to the Coriolis force when vibration is applied in the drive axis (eg, X axis) direction. Since the amplitude of the sense axis direction is proportional to the rotational angular velocity Omega _z, it is possible to detect the rotational angular velocity Omega _z by detecting the amplitude. In the AM mode, considering that the vibration applied in the drive axis direction directly excites the sense axis direction, the resonance frequencies in the drive axis and sense axis directions are set to be different (mode mismatch). However, in the AM mode, since measurement is performed at a frequency away from the resonance frequency, there is a problem that sensitivity is lowered.

The second method is a method called force rebalance, in which feedback control is performed so that the amplitude in the sense axis direction of the AM mode is always 0, and the rotational angular velocity is obtained from the magnitude of the feedback signal. In this case, a vibrator in which the resonance frequencies of the drive axis and the sense axis are matched (mode matched) can be used. However, there is a problem that the scale factor (the magnitude of the output with respect to the rotational angular velocity) varies depending on the temperature or the like.

In view of the above-described problems of the first and second methods, the embodiment of the present invention employs driving of the gyro device in the FM (Frequency Modulation) mode. The characteristics of the FM mode are that the sensitivity (scale factor) is more accurate and stable than the other methods, in principle, it has excellent temperature characteristics, and there is no limit on the dynamic range. Can be mentioned.

Here, the basic principle of the FM mode will be described. Since the principle of the FM mode itself is known, only a brief explanation is given here. An FM mode gyro is composed of a vibrator (also called a resonator or a resonator) that vibrates in two orthogonal (independent) directions. In the FM mode, a vibrator (mode match) in which the resonance frequencies in each axis are matched is used. In this state, it is known that the following Equation 1 is derived when a rotational angular velocity is given to the vibrator. In Equation 1, λ is a resonance frequency, ω is a resonance frequency when no rotation is given (the mode is matched, so both axes have the same resonance frequency), and Ω _z is a rotation angular velocity given to the vibrator. Yes.

Note that the vibration mentioned below is not limited to the linear direction (for example, the X direction and the Y direction), and any vibration can be used as long as it is a mode-matched orthogonal vibration mode in a plane. For example, in the case of a ring type resonator, as shown in FIGS. 1 and 2, two orthogonal vibrations are not necessarily simple linear vibrations, but the displacement state in each vibration mode is represented by mode coordinates (generalized). It can be handled in exactly the same way as linear vibration. In the following, including these mode coordinates (generalized coordinates), one mode is called "X axis (or X direction)", and a mode orthogonal to this is called "Y axis (or Y direction)" (note that Modes 1 and 2 in FIGS. 1 and 2 show a state where they are orthogonally mathematically or vibrationally).

The following formula 2 is derived from the formula 1.

That is, as shown by Equation 2, when the rotation is not given, the resonance frequencies in the X-axis and Y-axis directions match, that is, the mode matches, the resonance frequency λ becomes ω + Ω by giving the rotation. divided into a _z and ω-Ω _z. If these two resonance frequencies are λ ₁ and λ ₂ , the difference (deviation) between the resonance frequencies λ _{1 and} λ ₂ is proportional to the rotational angular velocity Ω _z , so that the two resonance frequencies λ ₁ and λ ₂ can be detected. For example, the rotational angular velocity Ω _z can be obtained by the following mathematical formula 3.

Here, the motion corresponding to λ ₁ (ω + Ω _z ) corresponds to clockwise (CW), and the motion corresponding to λ ₂ (ω−Ω _z ) corresponds to counterclockwise (CCW). That is, when rotation is applied to a mode-matching transducer, the natural vibration mode is not a straight line (vibration in the X direction or Y direction alone), but rotational vibration (the phase of vibration in the X and Y directions is ± 90 degrees (°) shifted two-dimensional vibration). Note that the actual rotation of the vibrator is a superposition of these CW mode and CCW mode.

“Methods for detecting components in each mode”
The FM mode has been described above. In the embodiment of the present invention, one vibrator (hereinafter, appropriately referred to as a two-dimensional vibrator) that is two-dimensionally matched in the above-described FM mode is excited. Therefore, in order to obtain the rotational angular speed Omega _z the components of component and CCW mode 2D CW mode included in the rotation vibration of the vibrator (output) (first rotational vibration mode) (second rotational vibration mode) Must be detected independently. Therefore, a method for separately detecting the CW mode component and the CCW mode component from the output of the two-dimensional vibrator will be described.

FIG. 3 is a diagram for explaining a general synchronous detection method. A signal having a predetermined amplitude (Amplitude) and phase (Phase) in the input signal (Signal) SI is input. The input signal SI is branched and input to each of the multipliers (mixers) 1 and 3. In the synchronous detection method, two signals whose phases are shifted by 90 degrees are used as reference signals, the reference signals are multiplied by separate multipliers 1 and 3, and then subjected to filter processing to obtain a demodulated output. For example, a cos wave and a sin wave are used as reference signals, a process for multiplying the input signal SI by the cos wave is performed by the multiplier 1, and a process for multiplying the input signal SI by the sin wave is performed by the multiplier 3.

The signal output from the multiplier 1 is input to the LPF (Low Pass Filter) 2 and filtered. By LPF2, the LPF2 outputs only components having the same frequency and the same phase as the reference signal (cos wave in this example).

On the other hand, the signal output from the multiplier 3 is input to the LPF 4 and subjected to filter processing. Due to the filtering process by the LPF 4, only components having the same frequency and the same phase as the reference signal (sin wave in this example) in the multiplier 3 are output from the LPF 4.

The input signal SI is demodulated by the outputs from the LPFs 2 and 4, and the amplitude r and phase θ of the input signal SI are detected based on the demodulated output.

In the embodiment of the present invention, processing for detecting CW mode components and CCW mode components is performed by developing and applying this synchronous detection method. In the following description, an example in which only the component of the CW mode is detected from the signal obtained by combining the CW mode and the CCW mode generated in the two-dimensional vibrator will be described. The component can be detected.

FIG. 4 is a diagram for explaining a method of detecting a CW mode component from the input signal SI. A signal output from the two-dimensional transducer is input as the input signal SI. When a two-dimensional vibrator is used, as shown in the figure, the input signal SI can be indicated by a vector notation including components in the X and Y directions.

The input signal SI is branched and input to each of the multipliers 1 and 3. Signals CW-I (In phase) and CW-Q (Quadrature Phase) are used as reference signals, the input signal SI is multiplied by the signal CW-I by the multiplier 1, and the input signal SI is signal CCW- A process of multiplying I is performed by the multiplier 3. The signal CW-I and the signal CW-Q are signals having the same amplitude, frequency, and rotation direction and having a phase shifted by 90 degrees, as symbolically shown in FIG.

The signal CW-I is multiplied by the multiplier 1 by the input signal SI, and the output is supplied to the LPF 2. The input signal SI is multiplied by the signal CW-Q by the multiplier 3 and the output is supplied to the LPF 4. As a result of the filtering process by the LPFs 2 and 4, the input signal SI is demodulated, and the amplitude r and phase θ of the CW mode component included in the input signal SI can be detected based on the demodulated output.

FIG. 5 is a diagram for explaining a detailed configuration example of the multipliers 1 and 3 described above. The multiplier 1 includes, for example, a multiplier 1a, a multiplier 1b, and an adder 1c. The multiplier 3 includes, for example, a multiplier 3a, a multiplier 3b, and an adder 3c.

As described above, in the case of a two-dimensional vibrator, signals (amplitudes) in the X-axis and Y-axis directions (hereinafter, appropriately referred to as signals SIX and SIY) are input to the multiplier 1 as the input signal SI. Multiplier 1a multiplies signal SIX by a component in the X-axis direction of signal CW-I, and multiplier 1b multiplies signal SIY by a component in the Y-axis direction of signal CW-I. The adder 1c adds the outputs of the multipliers 1a and 1b and outputs the result to the LPF 2.

The multiplier 3a multiplies the signal SIX by the component in the X-axis direction of the signal CW-Q, and the multiplier 3b multiplies the signal SIY by the component in the Y-axis direction of the signal CW-Q. The adder 3c adds the outputs of the multipliers 3a and 3b and outputs the result to the LPF 4.

The point that the component of the CW mode included in the output of the two-dimensional vibrator can be detected by the method described above will be described in more detail with reference to FIGS. The example shown in FIG. 6 is an example of detection using the signal CW-I as a reference signal. In this example, the signal in the X-axis direction of CW-I is a sin wave, and the signal in the Y-axis direction is a cos wave. Assuming that the input signal SI is only the component of the signal CW-I, the output waveform of the multiplier 1a is the waveform WA1a, and the output waveform of the multiplier 1b is the waveform WA2a. The waveform of the signal obtained by adding the outputs of the multipliers by the adder 1c is a waveform WA3a. When this signal waveform is passed through LPF2, the filtering process by LPF2 is equivalent to the process of obtaining an average, so that the waveform of the obtained signal becomes a waveform WA4a (DC component) similar to waveform WA3a. That is, when the input signal SI includes a component of the signal CW-I, the component can be detected by detection using the signal CW-I.

The example shown in FIG. 7 is an example of detection using the signal CW-I as a reference signal, but it is assumed that the input signal SI is only the component of the signal CW-Q that is 90 degrees out of phase with the signal CW-I. It is an example. In this case, the output waveform of the multiplier 1a is a waveform WA1b, and the output waveform of the multiplier 1b is a waveform WA2b. The signal obtained by adding the outputs of these waveforms by the adder 1c is 0 as shown in the figure, and therefore the output of the LPF 2 is also 0 as shown.

The example shown in FIG. 8 is an example of detection using the signal CW-I as a reference signal, but only the component of the counterclockwise signal CCW-I whose input signal SI is different from the signal CW-I in the rotation direction. This is an example. In this case, the output waveform of the multiplier 1a is a waveform WA1c, and the output waveform of the multiplier 1b is a waveform WA2c. The waveform of the signal obtained by adding the outputs of the multipliers by the adder 1c is a waveform WA3c that is symmetric about 0. When the signal of the waveform WA3a is passed through the LPF 2, the output becomes 0 as shown in the figure.

The example shown in FIG. 9 is an example in which detection is performed using the signal CW-I as a reference signal, but the input signal SI is a counterclockwise signal having a rotation direction different from that of the signal CW-I, and the signal CCW− This is an example in which only the component of the signal CCW-Q whose phase is 90 degrees different from I is assumed. In this case, the output waveform of the multiplier 1a is a waveform WA1d, and the output waveform of the multiplier 1b is a waveform WA2d. The waveform of the signal obtained by adding the outputs of the multipliers by the adder 1c is a waveform WA3d that is symmetric about 0. When the signal of the waveform WA3d is passed through the LPF 2, its output becomes 0 as shown.

That is, any two-dimensional vibration (represented by a linear combination of CW-I, CW-Q, CCW-I, and CCW-Q) generated in the two-dimensional vibrator is used with the signal CW-I as a reference signal. With synchronous detection, only the component of the signal CW-I included in the output signal of the two-dimensional transducer is obtained. This is also true for detected components when other signals are used as reference signals. In summary, the following Table 1 is obtained.

As shown in Table 1, when the output of the two-dimensional transducer includes the signal CW-Q component, the reference signal can be detected as the signal CW-Q, while the other signal components are output. 0. When the component of the signal CCW-I is included in the output of the two-dimensional vibrator, the reference signal can be detected as the signal CCW-I, while the output of other signal components is zero. When the output of the signal CCW-Q is included in the output of the two-dimensional transducer, the reference signal can be detected as the signal CCW-Q, while the output of other signal components is 0. That is, for example, if two detectors are provided and the reference signal in each detector is set to a combination of signal CW-I and signal CW-Q, and a combination of signal CCW-I and signal CCW-Q, respectively, two-dimensional vibration The CW mode component and CCW mode component can be detected independently from the output of the child.

"Example configuration of gyroscope"
Based on the above description, the gyro apparatus according to the first embodiment of the present invention will be described. FIG. 10 is a diagram illustrating a configuration example of the gyro apparatus (gyro apparatus 10) according to the first embodiment of the present invention. The gyro apparatus 10 includes, for example, a single two-dimensional vibrator 15, a drive signal generation unit 20, a first detection unit 30a, a first PLL (Phase Locked Loop) circuit 40a as an example of a first oscillation circuit, A first AGC (Automatic Gain Control) unit 50a as an example of a first gain control unit, a second detection unit 30b, a second PLL circuit 40b as an example of a second oscillation circuit, and an example of a second gain control unit The second AGC unit 50 b includes amplifiers 61 a and 61 b provided on the input side of the two-dimensional vibrator 15, and amplifiers 62 a and 62 b provided on the output side of the two-dimensional vibrator 15.

Although not shown, the gyro apparatus 10 may include a DA (Digital-to-Analog) converter and an AD (Analog-to-Digital) converter, and may be realized by digital signal processing. In this case, the DA converter is provided, for example, before the amplifiers 61a and 61b, and is configured to convert the digital drive signal output from the drive signal generation unit 20 into an analog format. Further, the AD converter is provided, for example, at the subsequent stage of the amplifiers 62a and 62b, and is configured to convert an analog signal output from the two-dimensional transducer 15 into a digital format.

The two-dimensional vibrator 15 is, for example, a vibrating member that has a ring shape and can be excited by a drive signal corresponding to each of the CW mode and the CCW mode. Note that the shape of the two-dimensional vibrator 15 is not limited to the ring shape, and may be any shape such as a regular square plate, a cylinder, a regular square column, a quadruple mass type using four masses, or the like. It is.

The drive signal generation unit 20 generates a drive signal corresponding to the CW mode and a drive signal corresponding to the CCW mode, and supplies the multiplexed drive signal to the two-dimensional vibrator 15. The two-dimensional vibrator 15 is excited by the drive signal supplied from the drive signal generator 20. In this example, a cosine wave (hereinafter referred to as “cos _cw signal”) as a drive signal in the X axis direction corresponding to the CW mode, and a −sin wave (hereinafter referred to as “−sin _cw signal”) as a drive signal in the Y axis direction. Is used. Note that the drive signal does not necessarily have to be a cos wave or a −sin wave as long as the Y direction signal has a phase advanced by 90 degrees compared to the X direction signal. Also, a -cos wave (hereinafter referred to as -cos _CCW signal) as a drive signal in the X-axis direction corresponding to the CCW mode, and a -sin wave (hereinafter referred to as -sin _CCW signal) as a drive signal in the Y-axis direction. Is used. Note that the drive signal is not necessarily a -cos wave or a -sin wave as long as the Y direction signal is 90 degrees behind the X direction signal. More specifically, the drive signal generation unit 20 includes, for example, a multiplier 201, a multiplier 202, a multiplier 203, a multiplier 204, an adder 205, and an adder 206.

The first detection unit 30 a detects the amplitude r _cw and the phase θ _cw of the CW component included in the output of the two-dimensional transducer 15. Details of the first detection unit 30a will be described later.

The first PLL circuit 40a includes a phase comparator 41a, a PID (Proportional Integral Differential) control unit 42a, and an oscillator 43a that can change an oscillation frequency such as a VCO (Voltage Controlled Oscillator) or an NCO (Numerical Controlled Oscillator). I have. Although detailed illustration is omitted in order to prevent the illustration from being complicated, the output of the first PLL circuit 40a (may be all or part of the output) may be the drive signal generator 20, It is configured to be fed back to each of the detection units 30a.

The first AGC unit 50a includes an amplitude comparator 51a and a PID control unit 52a. The output of the first AGC unit 50 a is configured to be fed back to the drive signal generation unit 20.

The second detection unit 30 b detects the amplitude r _CCW and the phase θ _CCW of the CCW component included in the output of the two-dimensional transducer 15. Details of the second detection unit 30b will be described later.

The second PLL circuit 40b includes a phase comparator 41b, a PID control unit 42b, and an oscillator 43b that can change an oscillation frequency such as a VCO or an NCO. Although detailed illustration is omitted in order to prevent the illustration from being complicated, the output of the second PLL circuit 40b (may be all or part of the output) may be the drive signal generator 20, It is configured to be fed back to each of the detection units 30b.

The second AGC unit 50b includes an amplitude comparator 51b and a PID control unit 52b. The output of the second AGC unit 50 b is configured to be fed back to the drive signal generation unit 20.

“Configuration example of first and second detectors”
FIG. 11 is a diagram for explaining a configuration example of the first detection unit 30a. The first detector 30a includes detectors 31a and 32a to which signals output from the two-dimensional transducer 15 are branched and input, an LPF 33a that performs filtering on the output of the detector 31a, and an output of the detector 32a. An LPF 34a that performs filter processing, and an amplitude phase detector 35a that detects the amplitude r _cw and the phase θ _cw of the CW component contained in the output signal of the two-dimensional transducer 15 based on the outputs from the LPF 33a and LPF 34a. .

The detector 31a is a multiplier 310a that receives an X-axis direction component of the output from the two-dimensional transducer 15, and a multiplier that receives an Y-axis component of the output from the two-dimensional transducer 15. 311a and an adder 312a for adding the outputs of the multipliers 310a and 311a. The detector 32 a is a multiplier 320 a that receives an X-axis direction component of the output from the two-dimensional transducer 15, and a multiplier that receives an Y-axis component of the output from the two-dimensional transducer 15. 321a and an adder 322a for adding the outputs of the multipliers 320a and 321a.

In this example, the CW-I component in the X-axis direction is a sin signal, the CW-I component in the Y-axis direction is a cos signal, the CW-Q component in the X-axis direction is a cos signal, and the CW in the Y-axis direction -Q component is -sin signal.

FIG. 12 is a diagram for describing a configuration example of the second detection unit 30b. The second detector 30b includes detectors 31b and 32b into which signals from the two-dimensional transducer 15 are branched and input, an LPF 33b that performs filtering on the output of the detector 31b, and a filtering process on the output of the detector 32b. And an amplitude phase detector 35b for detecting the amplitude r _CCW and the phase θ _CCW of the CCW component contained in the output signal of the two-dimensional transducer 15 based on the outputs from the LPF 33b and the LPF 34b.

The detector 31b is a multiplier 310b that receives an X-axis direction component of the output from the two-dimensional transducer 15, and a multiplier that receives an Y-axis component of the output from the two-dimensional transducer 15. 311b and an adder 312b for adding outputs from the multipliers 310b and 311b. The detector 32b is a multiplier 320b that receives an X-axis direction component of the output from the two-dimensional transducer 15, and a multiplier that receives an Y-axis component of the output from the two-dimensional transducer 15. 321b and an adder 322b that adds the outputs of the multipliers 320b and 321b.

In this example, the CCW-I component in the X-axis direction is the -sin signal, the CCW-I component in the Y-axis direction is the cos signal, the CCW-Q component in the X-axis direction is the -cos signal, and the Y-axis direction The CCW-Q component of the -sin signal.

"Operation example of gyroscope"
Next, an operation example of the gyro apparatus 10 will be described with reference to FIGS. The drive signal generation unit 20 generates a drive signal for the two-dimensional vibrator 15. For each of the cos _cw signal and the −sin _cw signal, the signal fed back from the PID control unit 52 a is multiplied by the multipliers 201 and 202, and then the output signal from the multiplier 201 is supplied to the adder 205. An output signal from the multiplier 202 is supplied to the adder 206. Each of the −cos _CCW signal and the −sin _CCW signal is multiplied by a signal fed back from the PID control unit 52 b by the multipliers 203 and 204, and then an output signal from the multiplier 203 is supplied to the adder 205. The output signal from the multiplier 204 is supplied to the adder 206. The adder 205 adds the output signal from the multiplier 201 and the output signal from the multiplier 203 and outputs the result. The output signal from the adder 205 is amplified with an appropriate amplification factor by the amplifier 61a, and then input to the two-dimensional vibrator 15 as an input _Xd . On the other hand, the adder 206 adds the output signal from the multiplier 202 and the output signal from the multiplier 204 and outputs the result. After the output signal from the adder 206 is amplified with an appropriate amplification factor by the amplifier 61b, as an input Y _d to the two-dimensional vibrator 15.

The two-dimensional vibrator 15 is excited by the inputs X _d and Y _d , and outputs X _s and Y _s from the two-dimensional vibrator 15 are obtained. After the outputs X _s and Y _s from the two-dimensional vibrator 15 are amplified with an appropriate amplification factor by the amplifiers 62a and 62b, the output X _s is branched and supplied to the first and second detection units 30a and 30b, respectively. The output Y _s is branched and input to each of the first and second detection units 30a and 30b.

The first detection unit 30 a detects a CW component included in the output of the two-dimensional transducer 15. Specifically, the detector 31a in the first detection unit 30a detects using the signal CW-I, and the result is subjected to filter processing by the LPF 33a, whereby CW-I included in the output of the two-dimensional transducer 15 is detected. The component is detected, and the detection result is supplied to the amplitude / phase detector 35a. In addition, the detector 32a in the first detection unit 30a detects using the signal CW-Q, and the result is filtered by the LPF 34a to detect the CW-Q component included in the output of the two-dimensional transducer 15. Then, the detection result is supplied to the amplitude / phase detector 35a. The amplitude phase detector 35a detects the amplitude r _cw and the phase θ _cw of the CW component included in the output signal of the two-dimensional transducer 15 based on the outputs from the LPF 33a and the LPF 34a. That is, as described above, only the CW component included in the output of the two-dimensional transducer 15 can be detected by performing synchronous detection using the signals CW-I and CW-Q as reference signals.

The phase θ _cw detected by the first detection unit 30a is supplied to the first PLL circuit 40a. The phase comparator 41a in the first PLL circuit 40a compares the phase θ _cw and the set phase θ _{cw, set} (in the following description, the explanation proceeds with θ _{cw, set} = 0), and based on the comparison result, the PID control unit The control 42a executes control so that the phase θ _cw becomes 0, that is, the resonance frequency f _cw . The oscillator 43a is controlled by the output from the PID control unit 42a, whereby the oscillator 43a outputs the signal sin _cw and the signal cos _cw having the resonance frequency f _cw in phase. These signals are fed back to the input side, and control is performed so that the resonance frequency of the drive signal corresponding to the CW mode is maintained at the resonance frequency _fcw . Further, the signal sin _cw and the signal cos _cw are fed back to the first detection unit 30a, and based on this, the signals CW-I and CW-Q as reference signals are generated. In this example, a relationship of sin = sin _cw , cos = cos _cw , and −sin = −1 * sin _cw is established between the fed back signal and the reference signal.

The amplitude r _cw obtained by the first detection unit 30a is supplied to the first AGC unit 50a. The amplitude comparator 51a in the first AGC unit 50a compares the amplitude r _cw with a predetermined first set value R _{set, cw,} and based on the comparison result, the PID control unit 52a determines that the amplitude r _cw is a predetermined first setting. Executes control with value R _{set, cw} . The output from the PID control unit 52a is fed back to the drive signal generation unit 20, and the gain is controlled so that the amplitude of the drive signal corresponding to the CW mode is maintained at the first set value R _{set, cw} .

Similar processing is executed for a system that detects a CCW component included in the output of the two-dimensional transducer 15. Specifically, the detector 31b in the second detection unit 30b detects using the signal CCW-I, and the result is subjected to filter processing by the LPF 33b, so that the CCW-I included in the output of the two-dimensional transducer 15 is obtained. The component is detected, and the detection result is supplied to the amplitude / phase detector 35b. In addition, the detector 32b in the second detection unit 30b detects using the signal CCW-Q, and the CCW-Q component included in the output of the two-dimensional transducer 15 is detected by performing filter processing on the result using the LPF 34b. Then, the detection result is supplied to the amplitude / phase detector 35b. The amplitude phase detector 35b detects the amplitude r _CCW and the phase θ _CCW of the CCW component included in the output signal of the two-dimensional transducer 15 based on the outputs from the LPF 33b and the LPF 34b. That is, as described above, only the CCW component included in the output of the two-dimensional transducer 15 can be detected by performing synchronous detection using the signals CCW-I and CCW-Q as reference signals.

The phase θ _CCW obtained by the second detection unit 30b is supplied to the second PLL circuit 40b. The phase comparator 41b in the second PLL circuit 40b compares the phase θ _CCW with 0, and based on the comparison result, the PID control unit 42b executes control for setting the phase θ _CCW to 0, that is, the resonance frequency f _cw . The oscillator 43b is controlled by the output from the PID control unit 42b, whereby the oscillator 43b outputs a signal sin _CCW and a signal cos _CCW having the resonance frequency f _CCW that are in phase. The resonance frequency f _CCW is fed back to the input side, and control is performed to maintain the resonance frequency of the drive signal corresponding to the CCW mode at the resonance frequency f _CCW . The signal sin _CCW and the signal cos _CCW are fed back to the second detection unit 30b, and based on this, the signals CCW-I and CCW-Q as reference signals are generated. In this example, between the signal and the reference signal fed _{back, -sin = sin ccw, cos =} cos ccw, -cos = -1 * cos ccw, the relationships are established.

The amplitude r _CCW obtained by the second detection unit 30b is supplied to the second AGC unit 50b. The amplitude comparator 51b in the second AGC unit 50b compares the amplitude r _CCW with the second set value R _{set, CCW,} and based on the comparison result, the PID control unit 52b sets the amplitude r _CCW to the second set value R _set, Executes _CCW control. The output from the PID control unit 52b is fed back to the drive signal generation unit 20, and control is performed to control the gain so that the amplitude of the drive signal corresponding to the CCW mode is maintained at the second set value R _{set, CCW} .

FIG. 13 is a diagram schematically showing a signal flow in the gyro apparatus 10. As shown in FIG. A thick line in FIG. 13 indicates a signal flow. The CCW component included in the output of the two-dimensional transducer 15 is cut by the first detection unit 30a, and only the CW component loops through one system (the upper system in FIG. 13). The CW component included in the output of the two-dimensional transducer 15 is cut by the second detection unit 30b, and only the CCW component loops through the other system (the lower system in FIG. 13).

"Configuration example of angular velocity detector"
Next, a configuration example of the angular velocity detection unit (angular velocity detection unit 70) according to the first embodiment of the present invention will be described. Although the angular velocity detection unit 70 is described as being incorporated in the gyro device 10, it may be incorporated in another device.

FIG. 14 is a diagram illustrating a configuration example of the angular velocity detection unit 70. The angular velocity detection unit 70 includes, for example, a subtracter 71 and a multiplier 72. The angular velocity detection unit 70 obtains the resonance frequency f _cw output from the first PLL circuit 40a and the resonance frequency f _CCW output from the second PLL circuit 40b, subtracts both resonance frequencies by the subtractor 71, and multiplies the result. 72 is multiplied by a constant (in the case of an ideal vibrator, 1/2 times). In other words, the angular velocity detection unit 70 detects the rotational angular velocity Ω _z by performing the same calculation as in the above-described Expression 3. By integrating this rotational angular velocity Ω _z , the gyro apparatus 10 can detect the rotated angle.

"effect"
According to the first embodiment of the present invention, the following effects can be obtained. Since the apparatus is composed of a single two-dimensional vibrator, it is possible to reduce the size of the apparatus, and it is not necessary to match the characteristics and use environment of the vibrator as in the case of using a plurality of vibrators. . In addition, since a single two-dimensional vibrator is driven by mode matching, a high Q value can be realized, and a high-performance gyro apparatus can be realized. Furthermore, components corresponding to the CW and CCW modes can be detected independently from the output of the two-dimensional transducer, and the rotational angular velocity can be detected from those detection results, and finally the rotated angle can be detected. it can.

<2. Second Embodiment>
Next, a second embodiment will be described. In the following description, the same name and reference sign indicate the same or the same members unless otherwise specified, and a duplicate description will be omitted as appropriate. The second embodiment is an embodiment configured as a gyro device in a Whole Angle Mode (also referred to as an integral gyro or the like, a typical example is a Foucault pendulum). The gyro apparatus in the hall angle mode can detect the rotated angle itself.

The hall angle mode will be schematically described with reference to FIG. When the resonator is rotated in the CW mode (resonance frequency ω + Ω _z ) and CCW mode (resonance frequency ω-Ω _z ), when both rotations have the same amplitude and no phase difference φ (φ = 0), As shown in FIG. 15A, the vibration is linear. Here, when rotation is applied to the vibrator, a phase difference φ is generated, and the direction of vibration is rotated by the phase difference φ as shown in FIG. 15B. It is known that the rotation angle in the vibration direction is ½ of the phase difference φ. For example, FIG. 15B shows an example in which the phase difference φ is 60 degrees, and the direction of vibration rotates by 1/2 (30 degrees) of the phase difference φ. In other words, the hall angle mode gyro apparatus can detect the phase difference φ and multiply the phase difference φ by 1/2 to detect the rotated angle itself.

The gyro device according to the second embodiment can have the same configuration as the gyro device 10 according to the first embodiment described above. What is necessary is just to provide the structure which detects a rotation angle in the structure of the gyro apparatus 10. FIG. FIG. 16A is a diagram illustrating a configuration example of an angle detection unit (angle detection unit 80a) that detects a rotation angle. The angle detection unit 80a includes a subtractor 81a and a multiplier 82a. If the phase of each CW, CCW mode (θ _cw , θ _CCW (which is different from the actual vibration phase with respect to the excitation signal of each mode) is θ ′ _cw , θ ′ _CCW , these are It can be obtained by reading internal variables of NCO. The subtractor 81a receives this phase θ ′ _cw and θ ′ _CCW . The subtractor 81a subtracts the phase θ ′ _cw and the phase θ ′ _CCW to obtain the phase difference φ, and the result is multiplied by a constant (1/2 times for an ideal XY vibrator) by the multiplier 82a, thereby rotating the rotation angle. (Angle) can be detected.

FIG. 16B is a diagram illustrating another configuration example of the angle detection unit. The angle detection unit 80b illustrated in FIG. 16B includes, for example, a demodulation unit 81b, a phase difference detection unit 82b that detects at least a phase difference, and a multiplier 83b. The demodulator 81b demodulates (synchronous detection) the cos _CCW signal supplied from the second PLL circuit 40b using the cos _cw signal and the sin _cw signal. Based on the result, the phase difference detector 82b detects the phase difference φ, and the multiplier 83b multiplies the detected phase difference φ by a constant (1/2 times for an ideal XY vibrator) to thereby adjust the rotation angle. Can be detected.

The angle detectors 80a and 80b may be incorporated in another device different from the gyro device 10, and processing for detecting the rotation angle may be performed by the other device. Further, the gyro apparatus 10 may include an angular velocity detection unit 70 (see FIG. 14) and an angle detection unit 80a (may be the angle detection unit 80b). With this configuration, it is possible to provide a gyro apparatus that supports both the FM mode and the hall angle mode. Furthermore, since the rotation angle can be detected without numerical integration, it is possible to avoid inconveniences such as generation of errors due to numerical calculation, increase in power consumption due to calculation load, and bandwidth limitation due to calculation speed.

It should be noted that the second embodiment can be modified as follows, for example. As in the second embodiment, the driving of the gyro apparatus 10 in the hall angle mode can continue the mechanical integration operation even when there is no power on the same principle as the Foucault pendulum. Using this characteristic, intermittent control can be performed to reduce power consumption in the gyro apparatus 10.

For example, by supplying power from a power source (not shown) for a certain period of time to operate the gyro device 10 to excite the two-dimensional vibrator 15 and then stopping the supply of power, the power to the gyro device 10 is intermittently supplied. The configuration is made. Even when the supply of power is stopped, the mechanical integration operation continues while the vibration of the two-dimensional vibrator 15 continues. Of course, since the vibration of the two-dimensional vibrator 15 is attenuated while the supply of power is stopped, the supply of power is resumed after a certain period. This control may be set by the user as a mode (power saving mode) different from the mode for executing the normal operation. In addition, a timer may be provided in the gyro apparatus 10 so that the supply of power is automatically stopped after a certain period of time has elapsed after the start of power supply. The configuration may be such that the supply of power is stopped when the amplitude r _cw and the amplitude r _CCW output from the first detection unit 30a and the second detection unit 30b reach a certain value. Such a configuration includes, for example, a configuration in which the gyro device 10 is supplied with a power supply unit (any primary battery, secondary battery, solar power generation device, etc.) and a power supply unit and electric power (all or one of the gyro device 10). And a control unit that turns on / off a switch provided between the first and second components).

<3. Third Embodiment>
Next, a third embodiment will be described. Unless otherwise specified, the matters described in the first and second embodiments described above can be applied to the third embodiment. Note that the same reference numerals are assigned to the same components, and redundant descriptions are omitted as appropriate.

The third embodiment is an embodiment for avoiding performance deterioration due to incompleteness (X-Y asymmetry) of the vibrator. The incompleteness of the vibrator means a difference in resonance frequency and attenuation coefficient in the X and Y directions, which is mainly caused by the asymmetry of the structure due to a manufacturing error of the vibrator.

Here, an ideal vibrator (vibrator driven by mode matching) will be described with reference to FIGS. The upper part of FIG. 17A is a graph showing an example of the drive signal in the X direction, and the lower part of FIG. 17A is a graph showing an example of the drive signal in the Y direction. The vertical axis in each graph indicates the level of the drive signal, and the horizontal axis indicates time (t). As shown in the figure, the phase difference (Δθ) of the drive signals in the X direction and the Y direction is 90 °.

FIG. 17B shows the vibration when the vibrator is excited by the drive vibration shown in FIG. 17A. The upper part of FIG. 17B shows the vibration in the X direction of the output of the vibrator, and the lower part of FIG. Of the output, the vibration in the Y direction is shown. The vibration in each direction is such that the phase of the drive signal in the corresponding direction is delayed by 90 °, and the phase difference between the vibration in the X direction and the vibration in the Y direction is maintained at 90 °. That is, when the vibrator is excited with a drive signal having a phase difference of 90 ° in the X direction and the Y direction, ideally, as shown in FIGS. 18A and 18B, the X direction is at the resonance point (resonance frequency f ₀ ). And the amplitude of vibration in the Y direction are the same, and the phase difference of vibration in the X direction and the Y direction is 90 °.

However, there is a case where the vibration of the vibrator becomes non-ideal vibration due to the incompleteness (mode mismatch) of the vibrator described above. For example, as shown in FIG. 19A, when the resonance frequencies in the X direction and the Y direction are shifted, the phase delay amount of the vibration with respect to the drive signal (frequency f ₀ ) is changed in the X direction and the Y direction as shown in FIG. 19B. Each will be different. For this reason, as shown in FIG. 19B, the amount of phase delay in the X and Y directions at the driving frequency f ₀ does not become 90 °, and a phase difference Δφ occurs.

As a result, as shown in FIGS. 20A and 20B, due to the imperfection of the vibrator, the phase delay of the vibration in the X direction is smaller than (or larger than) 90 ° with respect to the phase of the driving signal in the X direction, In some cases, the phase lag of the vibration of the motor is larger (or smaller) than 90 ° with respect to the phase of the drive signal in the Y direction. In such a case, the phase difference between the excited vibrations in the X and Y directions is not 90 °.

The effect of the mismatch described above on the processing system of the gyro apparatus 10 described in the first embodiment will be described. FIG. 21 is a block diagram showing the gyro apparatus 10 in a simplified manner. As described in the first embodiment, the first detection unit 30a detects a CW component included in the vibration of the two-dimensional vibrator 15, and is therefore referred to as a CW detector in FIG. . Similarly, since the second detection unit 30b detects a CCW component included in the vibration of the two-dimensional vibrator 15, it is represented as a CCW detector in FIG.

The fact that a phase difference occurs at the drive frequency mentioned above means that even if you intend to drive with CW (CCW), pure CW (CCW) vibration (the phase difference of each vibration in the X and Y directions is 90 ° (-90 °)) This means that the CCW (CW) component is generated at the same time.

As described in the first embodiment (see FIG. 13 and the like), in the gyro apparatus 10, the system in which the CW mode component loops and the system in which the CCW mode component loops should originally be independent. Unnecessary CCW mode components included in this component pass through the CCW detector. That is, a signal having CW mode information leaks to the CCW mode loop system, and the CW mode information enters the PLL (second PLL circuit 40b) in the CCW mode loop. As a result, the operation of the second PLL circuit 40b is disturbed by an unnecessary CCW mode component included in the CW mode, and the frequency at which the second PLL circuit 40b is locked is disturbed.

In the example described above, an example in which an unnecessary CCW mode component is included in the CW mode component has been described, but the same applies to the case in which the CCW mode component includes an unnecessary CW mode component. That is, an unnecessary CW mode component included in the CCW mode component disturbs the frequency at which the first PLL circuit 40a is locked.

Therefore, in order to cope with this problem, the phase of the drive signal is shifted in advance in order to cancel an unnecessary phase difference caused by imperfection of the two-dimensional vibrator 15 (phase adjustment processing). 22A and 22B, for example, when the phase difference between the drive vibration phase and the vibration phase in the X direction is smaller than 90 °, the phase difference and the drive signal phase are delayed in advance. Keep it. 22A and 22B, for example, if the phase difference between the drive vibration phase and the vibration phase in the Y direction is greater than 90 °, the phase difference and the drive signal phase are Advance in advance. Thereby, the phase difference between the vibration in the X direction and the vibration in the Y direction can be 90 °, and a pure eigenmode can be excited.

The phase difference to be compensated can be obtained from the difference in resonance frequency, for example. Note that the phase difference in which the vibration in the X direction and the vibration in the Y direction are most orthogonal may be obtained in advance by experiments or the like, and the phase of the drive signal may be delayed or advanced by the amount corresponding to the phase difference.

The incompleteness of the vibrator causes not only the above-described frequency shift but also a shift between the Q value (dumping) in the X direction and the Q value in the Y direction. When the Q values in the X direction and the Y direction are deviated, as shown in FIGS. 23 and 24, the vibration amplitude in the X direction and the vibration amplitude in the Y direction are different at the resonance point. If the amplitude of the vibration in the X direction is different from the amplitude of the vibration in the Y direction, it is no longer a natural vibration (circular vibration), and the CCW mode component is included in the CW mode vibration (CCW mode) as in the event described above. This causes a problem that the CW mode component is included in the vibration.

Therefore, as shown in FIG. 25, the deviation (mismatch) of the Q value is compensated by previously shifting the amplitude of the drive signal (amplitude adjustment processing). For example, as shown in FIG. 25B, the amplitude of the vibration amplitude and the Y-direction of the vibration in the X-direction should match the resonance point and the amplitude A _C. The amplitude A _C for by the amount of deviation, advance shifting the amplitude of the amplitude and the Y-direction driving signal for the X direction of the driving signal. In the example shown in the upper part of FIG. 25A, the amplitude of the drive signal is increased by the amount of vibration attenuation (ΔA _x ) generated between the amplitude of the drive signal in the X direction and the amplitude of the vibration in the X direction. In the example shown in the lower part of FIG. 25A, the amplitude of the drive signal is reduced by an increase in vibration (ΔA _y ) that occurs between the amplitude of the drive signal in the Y direction and the amplitude of the vibration in the Y direction. Of course, there are cases where the amplitude of the drive signal in the X direction is reduced or the amplitude of the drive signal in the Y direction is increased.

The amount of compensation for the amplitude is obtained from the difference in Q value, for example. Note that the compensation amount of the amplitude in which the vibration in the X direction and the vibration in the Y direction are most orthogonal may be obtained in advance by experiments or the like, and the amplitude of the drive signal may be increased or decreased by the compensation amount of the amplitude.

FIG. 26 is a block diagram illustrating a configuration example of the gyro apparatus (gyro apparatus 10A) according to the third embodiment to which the above-described function of adjusting the phase and amplitude is applied. The same components as those of the gyro device 10 are denoted by the same reference numerals. The drive signal generation unit 20A of the gyro apparatus 10A includes phase adjustment units 91, 92, 93, and 94 and amplitude adjustment units 95, 96, 97, and 98 in addition to the configuration of the drive signal generation unit 20 in the first embodiment. ing. The phase adjustment units 91 and 92 and the amplitude adjustment units 95 and 96 constitute a first phase / amplitude adjustment unit, and the phase adjustment units 93 and 94 and the amplitude adjustment units 97 and 98 constitute a second phase / amplitude adjustment unit. .

The phase adjustment unit 91 is connected to the input stage of the multiplier 201, and the amplitude adjustment unit 95 is connected to the output stage of the multiplier 201. The phase adjustment unit 91 and the amplitude adjustment unit 95 perform the above operation on the drive signal in the X direction in the CW mode in order to eliminate unnecessary phase difference and Q value shift caused by imperfection of the two-dimensional vibrator 15. The phase adjustment process and the amplitude adjustment process performed are executed.

The phase adjustment unit 92 is connected to the input stage of the multiplier 202, and the amplitude adjustment unit 96 is connected to the output stage of the multiplier 202. The phase adjustment unit 92 and the amplitude adjustment unit 96 are described above with respect to the drive signal in the Y direction in the CW mode in order to eliminate unnecessary phase difference and Q value deviation caused by imperfection of the two-dimensional vibrator 15. The phase adjustment process and the amplitude adjustment process performed are executed.

The phase adjustment unit 93 is connected to the input stage of the multiplier 203, and the amplitude adjustment unit 97 is connected to the output stage of the multiplier 203. The phase adjustment unit 93 and the amplitude adjustment unit 97 perform the above operation on the X-direction drive signal in the CCW mode in order to eliminate unnecessary phase difference and Q value deviation caused by imperfection of the two-dimensional transducer 15. The phase adjustment process and the amplitude adjustment process performed are executed.

The phase adjustment unit 94 is connected to the input stage of the multiplier 204, and the amplitude adjustment unit 98 is connected to the output stage of the multiplier 204. The phase adjustment unit 94 and the amplitude adjustment unit 98 perform the above operation on the drive signal in the Y direction in the CCW mode in order to eliminate unnecessary phase difference and Q value deviation caused by imperfection of the two-dimensional vibrator 15. The phase adjustment process and the amplitude adjustment process performed are executed. Each phase adjustment unit may be provided at the output stage of each multiplier, but the circuit configuration can be simplified by adjusting the phase of the drive signal before the arithmetic processing (multiplication) by the multiplier. The amplitude adjustment can also be realized by individually adjusting the magnifications of the multipliers 201 to 204.

The outputs of the amplitude adjustment units 95 and 97 are added by the adder 205, then amplified by the amplifier 61a, and supplied to the two-dimensional vibrator 15 as a drive signal in the X direction. The outputs of the amplitude adjusters 96 and 98 are added by the adder 206, then amplified by the amplifier 61b, and supplied to the two-dimensional vibrator 15 as a drive signal in the Y direction. The two-dimensional vibrator 15 is excited by drive vibration corresponding to each direction. As described above, since the phase and amplitude of the drive signal are adjusted in advance, the CW mode drive signal excites only pure CW mode vibration (CCW mode drive signal only pure CCW mode vibration). be able to.

The effect by applying the processing in the present embodiment will be described. The horizontal axis of the graph shown in FIG. 27A and FIG. 27B shows the time (t) (s), the vertical axis represents the difference between the frequency f _ccw frequency f _cw and oscillator 43b of the oscillator 43a Δf (Hz). The graph in FIG. 27A shows the result when the processing in the present embodiment is not applied, and the graph in FIG. 27B shows the result when the processing in the present embodiment is applied. As shown in FIG. 27A, since the CW mode and the CCW mode are not orthogonal due to a mismatch between the phase delay amount and the Q value, periodic fluctuations in frequency due to interference can be seen even though the CW mode and the CCW mode are rotating at a constant speed. On the other hand, when the processing in this embodiment is applied and the phase and amplitude of the drive signal are adjusted, the orthogonality between the modes is improved, and the periodic fluctuation of the frequency as shown in FIG. 27A is not seen. . Therefore, the angular velocity can be detected accurately.

The processing described in the third embodiment can also be applied to the second embodiment (hole angle mode gyro device). In this case, the same effect can be obtained. This effect will be described. 28A and 28B, the horizontal axis indicates time (t) (s), and the vertical axis indicates the rotation angle θ detected by the gyro device according to the second embodiment. The graph in FIG. 28A shows the result when the processing in the present embodiment is not applied, and the graph in FIG. 28B shows the result when the processing in the present embodiment is applied. The angle detected from rotating the two-dimensional vibrator 15 at a constant angular velocity should be a straight line. However, as shown in FIG. A periodic error appears in the angle. On the other hand, when the processing in this embodiment is applied and the phase and amplitude of the drive signal are adjusted, the orthogonality between the modes is improved, and the periodic error as shown in FIG. 28A is not seen. Therefore, the angle can be detected accurately.

<4. Modification>
As mentioned above, although several embodiment of this invention was described concretely, this invention is not limited to embodiment mentioned above, Various deformation | transformation are possible.

The present invention is not limited to a specific method or the like as long as it is a vibrator that mode-matches two-dimensionally, and the shape and excitation method (electrostatic, electromagnetic, piezoelectric, etc.).

The circuit that processes the output of the two-dimensional vibrator 15 can also be configured by an integrated circuit such as an ASIC (Application Specific integrated Circuit).

A configuration in which the gyro apparatus 10 includes other circuit elements or the like may be used as long as the effects of the present invention are achieved.

The gyro device of the present invention is a device other than the above (for example, various electronic devices such as game devices, imaging devices, smartphones, mobile phones, personal computers, automobiles, trains, airplanes, helicopters, small flying vehicles, space devices, etc. And may be used by being incorporated in a mobile body, a robot, or the like.

The configurations, methods, steps, shapes, materials, numerical values, and the like given in the above-described embodiments are merely examples, and different configurations, methods, steps, shapes, materials, numerical values, and the like may be used as necessary. . In addition, the present invention can be realized by an apparatus, a method, and a system (cloud system or the like) composed of a plurality of apparatuses, and the items described in the plurality of embodiments and the modifications are mutually compatible unless technical contradiction occurs. Can be combined.

DESCRIPTION OF SYMBOLS 10 ... Gyro apparatus 15 ... Two-dimensional vibrator 20 ... Drive signal generation part 30a ... 1st detection part 30b ... 2nd detection part 40a ... 1st PLL circuit 40b ... 1st 2PLL circuit 50a ... first gain control unit 50b ... second gain control unit 70 ... angular velocity detection unit 80a, 80b ... angle detection unit 91-94 ... phase adjustment unit 95-98 ...・ Amplitude adjuster
CW ... 1st mode
CCW ・ ・ ・ Second mode

Claims (10)

1. A single two-dimensional vibrator driven by a drive signal corresponding to the first rotational vibration mode and a drive signal corresponding to the second rotational vibration mode;
   A first detector for detecting an amplitude and a phase of a component corresponding to the first rotational vibration mode from a signal output from the two-dimensional vibrator;
   A gyro apparatus comprising: a second detection unit that detects an amplitude and a phase of a component corresponding to the second rotational vibration mode from a signal output from the two-dimensional vibrator.
2. Based on the phase detected by the first detector, a first resonance frequency corresponding to the first rotational vibration mode and a signal whose phase matches the phase detected by the first detector are output. One oscillator circuit,
   A first gain control unit that controls the gain so that the amplitude detected by the first detection unit becomes a first set value;
   Based on the phase detected by the second detector, a second resonance frequency corresponding to the second rotational vibration mode and a signal whose phase matches the phase detected by the second detector are output. Two oscillation circuits;
   The gyro apparatus according to claim 1, further comprising: a second gain control unit that controls a gain so that an amplitude detected by the second detection unit becomes a second set value.
3. The frequency and amplitude of the drive signal corresponding to the first rotational vibration mode are fed back so as to be the first resonance frequency and the first set value,
   The frequency and amplitude of the drive signal corresponding to the second rotational vibration mode are fed back so as to be the second resonance frequency and the second set value,
   A signal output from the first oscillation circuit is fed back to the first detection unit;
   The gyro apparatus according to claim 2, wherein a signal output from the second oscillation circuit is fed back to the second detection unit.
4. The first detection unit detects the amplitude and phase of the component corresponding to the first rotational vibration mode by performing synchronous detection using a signal fed back from the first oscillation circuit,
   The said 2nd detection part detects the amplitude and phase of a component corresponding to a said 2nd rotational vibration mode by performing synchronous detection using the signal fed back from the said 2nd oscillation circuit. Gyro device.
5. The gyro apparatus of any one of Claims 1 thru | or 4 provided with the angular velocity detection part which detects the angular velocity of rotation based on the said 1st resonance frequency and the said 2nd resonance frequency.
6. The angle detection part which detects the angle of rotation based on the phase difference of the component corresponding to the said 1st rotational vibration mode, and the component corresponding to the said 2nd rotational vibration mode is provided. A gyro device as described in 1.
7. The gyro apparatus according to any one of claims 1 to 6, wherein power is intermittently supplied.
8. A first phase / amplitude adjustment unit for adjusting the phase and amplitude of the drive signal corresponding to the first rotational vibration mode;
   The gyro apparatus according to claim 1, further comprising: a second phase / amplitude adjustment unit that adjusts a phase and an amplitude of a drive signal corresponding to the second rotational vibration mode.
9. Driving a single two-dimensional vibrator by a drive signal corresponding to the first rotational vibration mode and a drive signal corresponding to the second rotational vibration mode;
   Detecting the amplitude and phase of the component corresponding to the first rotational vibration mode from the signal output from the two-dimensional vibrator;
   A gyro apparatus control method for detecting an amplitude and a phase of a component corresponding to the second rotational vibration mode from a signal output from the two-dimensional vibrator.
10. The control method of the gyro apparatus according to claim 9, wherein the two-dimensional vibrator is intermittently driven.

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