Full angle mode hemispherical resonator gyroscope accurate control method and system

Abstract

The application discloses a full-angle mode hemispherical resonator gyro precise control method and system, relates to the technical field of hemispherical resonator gyro control, and determines the current working electrode through an eight-electrode time-sharing control algorithm; after zero-crossing comparison of an x signal, a zero-crossing comparison signal is transmitted to a phase tracker; the phase tracker outputs a local carrier with the same phase as an input signal through a CORDIC algorithm; meanwhile, after A / D sampling of the x signal and a y signal, the x signal and the y signal enter a frequency-phase control loop, an amplitude control loop and a quadrature control loop of a control module respectively; in addition, key parameters E, Q and L obtained through hemispherical resonator gyro electric signal solving are also taken as inputs and enter the control loop module, so that precise control of the hemispherical resonator gyro is realized; meanwhile, the key parameters S and R are used to calculate the precession angle of the hemispherical resonator gyro rotation and output. The application can make the full-angle mode hemispherical resonator gyro have the ability of high-precision measurement under the working conditions of a large dynamic measurement range and a long navigation time.

Description

Technical Field

[0001] This invention relates to the field of hemispherical resonator gyroscope control technology, specifically to a precise control method and system for a full-angle mode hemispherical resonator gyroscope. Background Technology

[0002] The hemispherical resonant gyroscope is a new generation of inertial sensing element. Its mechanical structure lacks the high-speed rotor and movable support found in classic gyroscopes. It utilizes the Coriolis effect generated by a hemispherical harmonic oscillator to induce mode shape shifts, thereby measuring angles or angular velocities. With a lifespan exceeding fifteen years, it boasts advantages such as high measurement accuracy, strong stability, radiation resistance, and long lifespan, making it particularly suitable for space applications. Currently, the United States, Russia, France, and China are conducting research and development on hemispherical resonant gyroscope technology. In recent years, my country has also made significant progress in developing its own hemispherical resonant gyroscope inertial reference. The Shijian-9 satellite was the first to carry a hemispherical resonant gyroscope inertial assembly developed by the 26th Research Institute of China Electronics Technology Group Corporation (CETC), successfully integrating it into the satellite's attitude control system.

[0003] The control circuits of hemispherical resonant gyroscopes generally come in two types: analog circuits and digital circuits. Analog circuits used in the control loop of hemispherical resonant gyroscopes have disadvantages such as severe temperature drift of analog devices, parameter changes with temperature, and easy introduction of noise by various modules of analog circuits. On the other hand, digital circuits have the advantages of high precision, high reliability, simple design, and less susceptibility to temperature, making them very suitable for use in the control loop of hemispherical resonant gyroscopes.

[0004] Hemispherical resonant gyroscopes generally have two operating modes: force-balanced and full-angle operating modes. In force-balanced mode, while ensuring the amplitude stability of the resonator drive, a precession control force is applied to the resonator using electrodes, causing the standing wave to be "bound" to a fixed position. When the external carrier rotates, the standing wave is "bound" by the control force, which is proportional to the rotational speed of the external carrier. In this mode, the hemispherical resonant gyroscope is a rate gyroscope. Due to the large Coriolis mass of the hemispherical resonant gyroscope, the efficiency of the electrostatic force used to balance the precession of the Coriolis force is not high, resulting in a small dynamic range for the gyroscope output. In full-angle operating mode, only the standing wave amplitude control force and orthogonal control force are applied to the hemispherical resonator, allowing the standing wave to precess freely under the Coriolis effect. The gyroscope output is achieved by detecting the angular increment information of the gyroscope. This mode is a rate integral gyroscope, which has the advantage of a wide range of angular rate output and can meet the requirements of accurate positioning, high-speed cruise, and precision strike of cruise missiles in the defense field. However, it has the disadvantage of complex and difficult control, which limits the accuracy of the hemispherical resonant gyroscope in full-angle mode.

[0005] How to develop a control method that enables a full-angle mode hemispherical resonator gyroscope to achieve high-precision measurement capabilities under conditions of large dynamic range and long endurance has become an urgent technical problem to be solved. Summary of the Invention

[0006] This invention provides a precise control method and system for a full-angle mode hemispherical resonator gyroscope, which solves the shortcomings of the difficulty and high control complexity of precise measurement methods for full-angle mode hemispherical resonator gyroscopes under conditions of large dynamic measurement range and long endurance.

[0007] To achieve the above objectives, the present invention adopts the following technical solution:

[0008] A method for precise control of a full-angle mode hemispherical resonator gyroscope includes the following steps:

[0009] S1: The eight electrodes of the hemispherical resonant gyroscope are grouped in time sequence using an eight-electrode time-division control algorithm to form driving electrodes and detection electrodes; at the same time, the detection electrodes use the eight-electrode time-division control algorithm to determine the x and y signals of the hemispherical resonant gyroscope.

[0010] S2: Obtain the x and y signals from the hemispherical resonant gyroscope and synchronize the resonant frequency to obtain the synchronized x and y signals;

[0011] S3: The synchronized x signal is subjected to zero-crossing comparison to obtain a zero-crossing comparison signal. The phase tracker outputs a local carrier using the CORDIC algorithm based on the zero-crossing comparison signal. At the same time, the synchronized x signal and the synchronized y signal are subjected to A / D sampling processing to obtain a digital signal.

[0012] S4: Based on the local carrier and the digital signal, the CORDIC algorithm is used to multiply the local carrier and the digital signal and then demodulate them to obtain the demodulated signal;

[0013] S5: Based on the demodulated signal, an error feedback control signal is obtained. Using the error feedback control signal, the time-division control of the hemispherical resonator gyroscope in full-angle mode is realized. At the same time, the precession angle is output based on the demodulated signal.

[0014] Further, in S1, the eight electrodes include: a 0° electrode, a 90° electrode, a 180° electrode, a 270° electrode, a 45° electrode, a 135° electrode, a 225° electrode, and a 315° electrode.

[0015] Further, in S1, the driving electrode includes: X drive and Y drive The detection electrode includes: X sence and Y sence ;

[0016] X sence Composed of 0° and 90° electrodes, Y sence Composed of 45° and 135° electrodes, X drive Composed of 180° and 270° electrodes, Ydrive It consists of a 225° electrode and a 315° electrode.

[0017] Furthermore, in S4, the demodulated signal includes: orthogonal axis amplitude information Q, harmonic oscillator vibration energy information E, harmonic oscillator frequency splitting phase difference information L, hemispherical resonant gyroscope precession angle cosine parameter R, and hemispherical resonant gyroscope precession angle sine parameter S;

[0018] The error feedback control signal includes a phase error signal, an amplitude error signal, and a quadrature error signal.

[0019] Furthermore, in S5, the step of outputting the precession angle based on the demodulated signal specifically includes:

[0020] Based on the cosine parameter R and sine parameter S of the precession angle of the hemispherical resonant gyroscope, the precession angle of the hemispherical resonant gyroscope can be obtained by the following formula (39).

[0021]

[0022] in, R is the precession angle of the hemispherical resonant gyroscope, and S is the cosine parameter of the precession angle of the hemispherical resonant gyroscope.

[0023] Further, in S5, obtaining the error feedback control signal based on the demodulated signal specifically includes:

[0024] The frequency-phase control loop obtains the phase error signal based on the phase difference information L obtained by the frequency splitting of the resonator.

[0025] The amplitude control loop obtains the amplitude error signal based on the vibration energy information e of the harmonic oscillator;

[0026] The orthogonal control loop obtains the orthogonal error signal based on the orthogonal axis amplitude information Q.

[0027] Furthermore, in S5, the time-division control of the hemispherical resonator gyroscope in full-angle mode using the error feedback control signal includes the following steps: the frequency-phase control loop tracks the resonant frequency of the resonator in real time according to the phase error signal, and uses a phase-locked loop to generate a reference signal with the same frequency and phase for signal calculation of the detection electrode and signal control quantity allocation of the drive electrode.

[0028] Furthermore, in S5, the step of using the error feedback control signal to realize the time-division control of the hemispherical resonator gyroscope in full-angle mode also includes the following steps: the amplitude control loop adjusts the voltage of the driving electrode according to the amplitude error signal to control the amplitude of the hemispherical resonator gyroscope.

[0029] Furthermore, in S5, the step of using the error feedback control signal to realize the time-division control of the hemispherical resonant gyroscope in full-angle mode also includes the following steps: the orthogonal control loop uses PI control to reduce the amplitude of the orthogonal axis vibration to zero according to the orthogonal error signal, and performs orthogonal control on the hemispherical resonant gyroscope.

[0030] A precise control system for a full-angle mode hemispherical resonator gyroscope includes:

[0031] An eight-electrode time-division control module is used to group the eight electrodes of a hemispherical resonant gyroscope in time sequence using an eight-electrode time-division control algorithm to form driving electrodes and detection electrodes; at the same time, the detection electrodes use the eight-electrode time-division control algorithm to determine the x and y signals of the hemispherical resonant gyroscope.

[0032] The resonant frequency synchronization module is used to acquire x and y signals from the hemispherical resonant gyroscope and synchronize the resonant frequency to obtain synchronized x and y signals.

[0033] The zero-crossing comparison and A / D sampling module is used to perform zero-crossing comparison on the synchronized x signal to obtain a zero-crossing comparison signal. The phase tracker outputs a local carrier using the CORDIC algorithm based on the zero-crossing comparison signal. At the same time, the synchronized x signal and the synchronized y signal are subjected to A / D sampling processing to obtain a digital signal.

[0034] The signal demodulation module is used to multiply the local carrier and the digital signal using the CORDIC algorithm and then demodulate them to obtain the demodulated signal.

[0035] The control loop module is used to obtain an error feedback control signal based on the demodulated signal, and to use the error feedback control signal to realize time-division control of the hemispherical resonator gyroscope in full-angle mode; at the same time, it outputs the precession angle based on the demodulated signal.

[0036] Compared with the prior art, the present invention has the following beneficial effects:

[0037] This invention provides a precise control method for a full-angle mode hemispherical resonator gyroscope. It employs a simple, vibration-resistant "two-piece" hemispherical resonator gyroscope with eight flat plates as the controlled object. The eight-electrode time-division control scheme replaces the traditional ring electrode, significantly reducing assembly difficulty and making it easier to achieve uniform gain in all directions. This enables the large-scale manufacturing and application of high-quality hemispherical resonator gyroscopes. Furthermore, the eight-electrode time-division detection algorithm avoids the error term introduced by the difficulty in maintaining consistent gain between the drive and detection signal channels during standing wave (SWR) driving and detection using fixed electrodes. This ensures hardware gain consistency in the drive and detection loops and eliminates in-phase errors caused by inconsistent gain across channels. The time-division control algorithm incorporates a specific loss time interval to suppress the coupling of the drive signal to the detection direction, reducing detection errors and minimizing crosstalk caused by distributed capacitance. The phase tracker based on the CORDIC algorithm can complete all local carrier generation tasks. The algorithm involves only addition and shift operations, consuming few resources and reducing system latency. It can also be used to demodulate signals. This invention reduces the impact of errors on the gyroscope detection accuracy by controlling the precession of standing waves, further improving the system's stability and accuracy. This enables the full-angle mode hemispherical resonator gyroscope to have high-precision measurement capabilities under conditions of large dynamic measurement range and long endurance, meeting the needs of aviation and other fields.

[0038] This invention provides a precise control system for a full-angle mode hemispherical resonator gyroscope. The control loop module uses three basic control loops: an amplitude control loop, a frequency-phase control loop, and a quadrature control loop. The frequency-phase control loop maintains the driving signal and the detection signal of the hemispherical resonator electrode in phase, so that the excitation is synchronized with the resonance of the resonator. The amplitude control loop replenishes energy to the resonator, maintaining the vibration amplitude of the resonator lip without attenuation. The quadrature control loop minimizes the vibration amplitude of the resonator standing wave along the quadrature axis, continuously pushing the quadrature axis amplitude to zero. Attached Figure Description

[0039] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0040] Figure 1 This is a block diagram of the overall control scheme for a precise control method of a full-angle mode hemispherical resonant gyroscope according to the present invention;

[0041] Figure 2 The Lissajous figure shows the Lissajous electrical signal of the hemispherical resonant gyroscope for the precise control method of the full-angle mode hemispherical resonant gyroscope of the present invention;

[0042] Figure 3 This is a block diagram of an eight-electrode time-division control system for a precise control method of a full-angle mode hemispherical resonant gyroscope according to the present invention.

[0043] Figure 4 This is an eight-electrode time-division control timing diagram of a precise control method for a full-angle mode hemispherical resonant gyroscope according to the present invention;

[0044] Figure 5 This is a schematic diagram of the phase tracker working principle of a precise control method for a full-angle mode hemispherical resonant gyroscope according to the present invention.

[0045] Figure 6 This is a schematic diagram illustrating the signal demodulation principle of a precise control method for a full-angle mode hemispherical resonator gyroscope according to the present invention.

[0046] Figure 7 This is a frequency phase control loop diagram of a precise control method for a full-angle mode hemispherical resonant gyroscope according to the present invention;

[0047] Figure 8 This is an amplitude control loop diagram of a precise control method for a full-angle mode hemispherical resonant gyroscope according to the present invention;

[0048] Figure 9 This is an orthogonal control loop diagram of a precise control method for a full-angle mode hemispherical resonant gyroscope according to the present invention;

[0049] Figure 10 This is the precession angle output loop diagram of a precise control method for a full-angle mode hemispherical resonator gyroscope according to the present invention.

[0050] Figure 11 This is a schematic diagram of the full-angle mode hemispherical resonator gyroscope precision control system of the present invention;

[0051] Figure 12 This is a flowchart illustrating the precise control system for the full-angle mode hemispherical resonator gyroscope of the present invention. Detailed Implementation

[0052] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention.

[0053] This invention provides a precise control method for a full-angle mode hemispherical resonator gyroscope based on a digital control loop. It is implemented using a hemispherical resonator gyroscope, an eight-electrode time-sharing controller (electrode switching module), a phase tracker, a signal demodulation module, and a control loop module. A simple, vibration-resistant "two-piece" hemispherical resonator gyroscope with eight flat electrodes is used as the controlled object. The eight-electrode time-sharing control algorithm ensures the consistency of hardware gain between the drive and detection loops, eliminating in-phase errors caused by inconsistent gains across channels and simplifying hardware resources. The phase tracker generates a high-precision local carrier wave. The signal demodulation module demodulates three signals. The amplitude control loop in the control loop module maintains the resonator's vibration amplitude without attenuation. The frequency-phase control loop maintains the drive signal and the hemispherical resonator electrode detection signal in phase, synchronizing the excitation with the resonator's resonance. The orthogonal control loop minimizes the orthogonal axis vibration amplitude of the resonator's standing wave, continuously pushing the orthogonal axis amplitude to zero.

[0054] The hemispherical resonator gyroscope's detection is accomplished using a planar electrode system, comprising eight electrodes located at the bottom of the resonator. Each electrode is connected to an external control system via a conductive pin. Signals from the 0°, 90°, 180°, and 270° electrodes are superimposed to form the cosine signal required by the control system; signals from the 45°, 135°, 225°, and 315° electrodes are superimposed to form the sine signal required by the control system. By processing these two signals, the precession angle of the resonator can be obtained.

[0055] A method for precise control of a full-angle mode hemispherical resonator gyroscope includes:

[0056] The 0° and 45° electrode signals were used to calculate parameters containing the resonator's vibration energy information, denoted by E; parameters containing the orthogonal axis amplitude information, denoted by Q; parameters containing the hemispherical resonator gyroscope's precession angle information, denoted by R and S respectively; and parameters containing the phase difference information of the resonator's frequency split, denoted by L. Based on these key parameters, subsequent implementations of frequency and phase control, energy replenishment (amplitude control), orthogonal control, and precession angle output for the hemispherical resonator gyroscope were achieved.

[0057] The eight-electrode time-division control algorithm divides the eight electrodes of the hemispherical resonant gyroscope into four groups in time sequence, namely X sence X drive Y sence Y drive In terms of hardware, it is divided into two groups of positive and negative electrodes to form differential driving and detection;

[0058] The x and y input signals are obtained from the readout electrodes of the gyroscope, and A / D sampling processing is performed. The resonant frequency is synchronized. The x signal corresponds to the 0° electrode signal and the y signal corresponds to the 45° electrode signal.

[0059] After being synchronized with the resonant frequency, the x signal undergoes a zero-crossing comparison, and the zero-crossing comparison signal is then transmitted to the phase tracker.

[0060] The phase tracker estimates the carrier frequency by the interval between two zero-crossing signals, calculates the corresponding phase accumulation step, performs step accumulation, and finally outputs a carrier with the same phase as the input signal.

[0061] The x signal, after being synchronized with the resonant frequency, and the y signal, after being synchronized with the resonant frequency, are sampled together by an A / D converter, and the digital signal after A / D sampling is transmitted to the signal demodulation module.

[0062] The signal demodulation module converts the local carrier V generated by the phase tracker rc V rs The signal is multiplied with the x and y signals for demodulation, and the demodulated signal is then transmitted to the frequency phase tracking loop, amplitude control loop, and quadrature control loop of the control loop module, respectively.

[0063] The phase tracking loop tracks the resonant frequency of the resonator in real time under normal gyroscope operation, and uses the phase-locked loop to generate a reference signal with the same frequency and phase for the calculation of the hemispherical resonant gyroscope detection signal and the allocation of the control quantity of the drive signal.

[0064] The amplitude control loop obtains the total energy E of the current hemispherical resonant gyroscope through signal demodulation, compares E with the set energy value, and obtains an error signal, which serves as the control signal for the PI controller to control the magnitude of the drive voltage. The obtained drive voltage amplitude U0 is then used in conjunction with the drive frequency ω generated by the frequency response tracking loop and the gyroscope output precession angle. Synthesize 0° electrode axis drive signal 45° electrode axis drive signal After high-voltage amplification, the two signals are applied to the hemispherical resonant gyroscope, thereby controlling the amplitude of the hemispherical resonant gyroscope.

[0065] The quadrature control loop uses the judgment quantity q, that is, the vibration amplitude of the harmonic oscillator on the quadrature axis, to suppress the vibration amplitude of the quadrature axis to zero through PI control.

[0066] A further improvement of the present invention is that:

[0067] The eight-electrode time-sharing control algorithm specifically involves: designing a certain loss time interval, where the time-sharing period is related to the resonant frequency of the resonator and is provided by the phase tracking loop of the control system; the electrode switching module divides the eight electrodes into four groups in time sequence, namely X... sence X drive Y sence Y driveThe hardware consists of two groups: positive and negative electrodes. In the detection timing mode, the displacement signal of the resonator is sampled by an A / D converter after passing through the electrode switching module. After being synchronized with the resonant frequency, it enters the demodulation stage. The error feedback control signal is then directly applied to the driving electrode through the electrode switching module, forming a closed loop of phase, amplitude, and quadrature, thus realizing time-division control in full-angle mode.

[0068] The phase tracker specifically refers to: a known vector (x) i ,y i ), and rotation θ i The rotated vector value is calculated using the following formula:

[0069]

[0070] After summing equation (1) n times, we get:

[0071]

[0072] In the formula: K represents the value of x after n iterations. n ,y n The scaling factor (i.e., cosθ in each iterative equation) i The product of ( ), and the following relationship exists:

[0073]

[0074] Therefore, when x0 = K, y0 = 0, and z0 is the phase accumulation value in the control loop, the local carrier can be obtained from the relationship obtained after accumulating n times:

[0075]

[0076] The signal demodulation module specifically involves multiplying the local carrier generated by the phase tracker with x and y to complete demodulation. The demodulation process of the signal demodulation module based on the CORDIC algorithm is as follows: Taking the x-line as an example, the initial values ​​of the above formula are set as follows: x0 is the input gyroscope signal, x,y0 = 0, and z0 is the phase accumulation value.

[0077]

[0078] The frequency phase tracking loop consists of signal demodulation, a digital synthesizer, and a PI controller. The phase-locked loop is composed of an oscillator generator. The phase detector of the phase-locked loop is formed after the reference signal and the detection signal are calculated and adjusted by the PI controller. The specific process is as follows: the frequency phase tracking loop uses the parameter L calculated by the signal demodulation module as the phase judgment quantity (phase error): L = (a 2 -q 2By adjusting the frequency of the reference signal using a PI controller to make L = 0, the frequency of the reference signal will be the same as the actual resonant frequency of the harmonic oscillator, thus achieving frequency tracking.

[0079] The amplitude control loop specifically involves using the parameter E calculated by the signal demodulation module, and taking the arithmetic square root of parameter E as the judgment quantity (amplitude error). Adjusting the driving voltage so that Amp = A0 allows for amplitude control of the hemispherical resonant gyroscope. Here, Amp is the decision value of the amplitude control loop, and A0 is the amplitude corresponding to the resonant frequency of the hemispherical resonant gyroscope.

[0080] The orthogonal control loop is specifically defined as follows: the orthogonal control loop uses the parameter Q (orthogonal error) calculated by the signal demodulation module, and uses the following formula as the judgment quantity of the orthogonal control loop;

[0081]

[0082] The judgment quantity in Equation 6 above is the vibration amplitude of the resonator on the orthogonal axis. By using PI control, the vibration amplitude of the orthogonal axis is reduced to zero, thereby achieving orthogonal control of the hemispherical resonant gyroscope.

[0083] like Figure 11 and Figure 12 As shown, the present invention provides a precise control system for a full-angle mode hemispherical resonator gyroscope, comprising:

[0084] An eight-electrode time-division control module is used to group the eight electrodes of a hemispherical resonant gyroscope in time sequence using an eight-electrode time-division control algorithm to form driving electrodes and detection electrodes; at the same time, the eight-electrode time-division control algorithm is used to determine the x and y signals of the hemispherical resonant gyroscope through the detection electrodes.

[0085] The resonant frequency synchronization module is used to acquire x and y signals from the hemispherical resonant gyroscope and synchronize the resonant frequency to obtain synchronized x and y signals.

[0086] The zero-crossing comparison and A / D sampling module is used to perform zero-crossing comparison on the synchronized x signal to obtain a zero-crossing comparison signal. The phase tracker outputs a local carrier using the CORDIC algorithm based on the zero-crossing comparison signal. At the same time, the synchronized x signal and the synchronized y signal are subjected to A / D sampling processing to obtain a digital signal.

[0087] The signal demodulation module is used to demodulate the local carrier and the digital signal by multiplying them using the CORDIC algorithm, based on the local carrier and the digital signal, to obtain the demodulated signal.

[0088] The control loop module is used for the amplitude control loop, frequency phase control loop, and quadrature control loop to obtain error feedback control signals based on the demodulated signals. The error feedback control signals are used to realize the time-division control of the hemispherical resonator gyroscope in full-angle mode. At the same time, the precession angle is output based on the demodulated signals.

[0089] Example

[0090] The method for measuring angle and angular rate in a hemispherical resonant gyroscope is essentially achieved by measuring the mode shape position and amplitude of the resonator. The detection electrodes then use the obtained mode shape information to calculate the angle and angular velocity based on the precession theory of the hemispherical resonant gyroscope. In full-angle operation mode, the gyroscope applies standing wave amplitude control force and orthogonal control force only to the hemispherical resonator, allowing the standing wave to precess freely under the Coriolis effect. The gyroscope output is achieved by detecting the angular increment information, making it a rate integral gyroscope. The advantages of this operating mode are: large dynamic range, high accuracy over long endurance, and no inverse relationship between dynamic range and theoretical accuracy limits. It can adapt to the high-dynamic, long-endurance operating environment of airborne inertial sensors, meeting the needs of future aviation exploration, strategic weapons, and other fields. The disadvantages are: high control difficulty, high precision requirements for the instrument head manufacturing, and significant impact from standing wave drift.

[0091] Based on this, the present invention provides a method for achieving precise control of a hemispherical resonant gyroscope in full-angle operating mode, thereby addressing the requirements of long endurance and high precision for hemispherical resonant gyroscopes in aviation applications.

[0092] In full-angle mode, control requires the hemispherical resonant gyroscope to be in a second-order oscillation state, with the harmonic oscillator lip deforming within two orthogonal ellipses. The protons along the harmonic oscillator lip undergo pendulum-like motion. See also Figure 2 The Lissajous figures of the superimposed changes in the x-axis and y-axis electrical signals form an ellipse, where x and y represent the principal axis of the harmonic oscillator and the orthogonal axis at 45° in space: the x-axis coincides with the 0° electrode axis; the y-axis coincides with the 45° electrode axis; a is the principal axis antinode; and q is the orthogonal axis antinode. The phase variable is the principal axis; ω is the resonant frequency of the hemispherical vibration. The angle between the main wave antinode axis and the 0° electrode axis; t is time.

[0093] The vibration displacement equations along the x-axis and y-axis are written as follows:

[0094]

[0095] A reference signal with the same natural resonant frequency as the resonator is selected; this signal is generated by a phase-locked loop.

[0096]

[0097] In the formula, A is the amplitude of the reference signal; V is the phase of the reference signal. s It is a sinusoidal reference signal with the same resonant frequency and phase as the natural resonant frequency of the harmonic oscillator, V c It is a cosine reference signal with the same resonant frequency and phase as the natural resonant frequency of the harmonic oscillator.

[0098] The reference signal is multiplied pairwise by the x-axis and y-axis signals, as follows:

[0099] x signal and V s Multiplying the signals yields S c :

[0100]

[0101] After passing through a low-pass filter to remove higher-order terms containing 2ωt, we obtain:

[0102]

[0103] x signal and V c Signal multiplication yields C x :

[0104]

[0105]

[0106] After passing through a low-pass filter to remove higher-order terms containing 2ωt, we obtain:

[0107]

[0108] y signal and V s Multiplying the signals yields S y :

[0109]

[0110] After passing through a low-pass filter to remove higher-order terms containing 2ωt, we obtain:

[0111]

[0112] y signal and V c Signal multiplication yields C y :

[0113]

[0114] After passing through a low-pass filter to remove higher-order terms containing 2ωt, we obtain:

[0115]

[0116] Will Denoteed as δ, Let k be the value of k, then we have:

[0117]

[0118]

[0119]

[0120]

[0121] The above four equations can be combined and calculated as follows:

[0122] This ensures that the Q value includes orthogonal axis magnitude information:

[0123]

[0124] This ensures that the value of E contains energy information about the harmonic oscillation:

[0125] E=C x 2 +S y 2 +C y 2 +S x 2 =(ka) 2 +(kq) 2 =k 2 (a 2 +q 2 ) (twenty two)

[0126] This ensures that the R and S values ​​contain the energy information of the hemispherical resonant gyroscope.

[0127]

[0128]

[0129]

[0130] This ensures that the value of L contains the phase difference information of the harmonic oscillator frequency splitting:

[0131]

[0132] Let k = 1, then by further transforming the above equations, the control parameter equations for the hemispherical resonant gyroscope are:

[0133] Q = 2(C x S y -C y Sx )=2aq (26)

[0134] E=C x 2 +S y 2 +C y 2 +S2 2 =a 2 +q 2 (27)

[0135]

[0136]

[0137] L=2(C x S x +C y S y )=(a 2 -q 2 sin(2δ) (30)

[0138] Above, S x It is a sinusoidal reference signal V with the same resonant frequency and phase as the natural resonant frequency of the harmonic oscillator. s The product of the x signal; C x It is a cosine reference signal V with the same resonant frequency and phase as the natural resonant frequency of the harmonic oscillator. c The product of the x signal; S y It is a sinusoidal reference signal V with the same resonant frequency and phase as the natural resonant frequency of the harmonic oscillator. s The product of the y signal and C; y It is a cosine reference signal V with the same resonant frequency and phase as the natural resonant frequency of the harmonic oscillator. c The product of the y signal and the y signal.

[0139] This invention discloses a precise control method for a full-angle mode hemispherical resonator gyroscope, comprising the following steps:

[0140] See Figure 1For the full-angle control mode of the hemispherical resonator gyroscope, the eight-electrode time-division control algorithm determines the currently operating 0° and 45° electrodes. After zero-crossing comparison, the x-signal is transmitted to the phase tracker, which outputs a local carrier with the same phase as the input signal through the CORDIC algorithm. Simultaneously, the x and y signals are sampled by an A / D converter and then split into three paths, which enter the frequency-phase control loop, amplitude control loop, and quadrature control loop of the control module, respectively. In addition, the key parameters E, Q, and L obtained from the electrical signal calculation of the hemispherical resonator gyroscope are also input into the control module. The frequency-phase tracking loop tracks the resonant frequency of the resonator under normal operating conditions of the hemispherical resonator gyroscope in real time and generates a reference signal with the same frequency and phase to calculate the control quantities of the hemispherical resonator gyroscope detection signal and the distribution drive signal. That is, the key parameter L is obtained from the signal calculation, and the reference signal V is adjusted. s and V c The phase and frequency are such that L = 0. The amplitude control loop and the quadrature control loop control the amplitude of the resonator on the quadrature axis to zero, so that the signals output by the 0° electrode axis and the 45° electrode axis of the hemispherical resonant gyroscope remain in phase; the precession angle of the hemispherical resonant gyroscope is calculated and output using the key parameters S and R.

[0141] S1, see S1 Figure 1 and Figure 3 In the detection timing operation, the displacement signal of the resonator enters the A / D sampling module after passing through the electrode switching module. After being synchronized with the resonant frequency, it enters the demodulation stage. After calculation, phase error, amplitude error, and orthogonality error are generated. Each error is controlled after being calculated by the control module. Then, the standing wave angle is filtered by a low-pass filter to form the azimuth angle output. At the same time, the error feedback control signal is directly applied to the driving electrode through the electrode switching module, forming a closed loop of phase, amplitude, and orthogonality, realizing time-division control in full-angle mode.

[0142] See Figure 4 The phase tracking loop of the control system provides the resonant frequency of the resonator, which determines the time-division period. The electrode switching module divides the eight electrodes into four groups in time sequence, namely X... sence X drive Y sence Y drive Specifically: X sence Composed of 0° and 90° electrodes, X drive Composed of 180° and 270° electrodes, Y sence Composed of 45° and 135° electrodes, Y drive It consists of 225° and 315° electrodes, forming a differential drive and detection.

[0143] S2, the phase tracker estimates the carrier frequency using the interval between two zero-crossing signals, see [link / reference]. Figure 5 The zero-crossing comparison signal is used to obtain the count N from the counter. The quotient of 360° and N is obtained using the 360 / N module, which is the phase accumulation step C. p C p After accumulating itself in the phase accumulator register, the required sine and cosine addresses are obtained. Then, the local carrier with the same phase as the input signal is output through the CORDIC algorithm.

[0144] See Figure 6 The basic principle of the CORDIC algorithm is as follows: Given a vector (x... i ,y i ), and rotation θ i The rotated vector value is calculated using the following formula:

[0145]

[0146] In the formula: 0 ≤ i ≤ n. Here, n is the iteration number. The larger n is, the greater x n y n The closer it gets to the true target value, the closer it will be.

[0147] The rotation angle for each iteration is shown in Table 1 below:

[0148] Table 1 Iterative Rotation Angle Table

[0149] 0 45 1 1 26.555 1 / 2 2 14.036 1 / 4 3 7.125 1 / 8 4 3.576 1 / 16 ··· ··· ···

[0150] After summing equation (31) n times, we get:

[0151]

[0152] In the formula: K represents the value of x after n iterations. n ,y n The scaling factor (i.e., cosθ in each iterative equation) i The product of ( ), and the following relationship exists:

[0153]

[0154] Therefore, when x0 = K, y0 = 0, and z0 is the phase accumulation value in the control loop, the local carrier can be obtained from the relationship obtained after accumulating n times:

[0155]

[0156] The local carrier generated by the phase tracker and the x and y signals after A / D sampling enter the demodulation module. The product of the output signal and the local carrier is directly output through the CORDIC algorithm to complete the demodulation of the three signals.

[0157] See Figure 6The demodulation process of the signal demodulation module based on the CORDIC algorithm is as follows: Taking the x-line as an example, the initial values ​​of the above formula are set as follows: x0 is the input gyroscope signal x, y0 = 0, z0 is the phase accumulation value, then

[0158]

[0159] S3, the demodulated signals enter the frequency phase tracking loop, amplitude control loop and quadrature control loop of the control loop module respectively.

[0160] Among them, see Figure 7 The frequency-phase tracking loop consists of signal demodulation, a digital signal synthesizer, and a PI controller. The process is as follows: the signal demodulation module calculates parameter L using the generated reference signal, and adjusts the frequency of the reference signal to L=0 using the PI controller. The digital signal synthesizer generates a reference signal with the same resonant frequency as the hemispherical resonant gyroscope, and after phase compensation, generates a reference signal with the same phase as the hemispherical resonant gyroscope. Specifically, the frequency-phase tracking loop obtains the phase difference between the output signal and the resonant signal of the resonator using parameter L. The oscillator adjusts the phase and frequency of the reference signal based on the magnitude of the phase difference. Through continuous iteration, the frequency and phase of the output drive signal are made to infinitely approximate the resonant signal.

[0161] If the frequency difference between the harmonic oscillation signal and the output tracking signal is Δω, and the phase difference is... The resonant signal is cos(ωt). Without iteration, the mathematical expression for the output tracking signal can be:

[0162]

[0163] Transforming equation (36) above, we get:

[0164]

[0165] By continuously judging the phase deviation of the phase detector output, the phase difference is adjusted. Simultaneously, the frequency and phase errors of the tracker signal are tuned to ensure that they eventually match the frequency and phase of the resonant signal. A designed PI controller ensures that Δω = 0 at any given time. That is

[0166] Among them, see Figure 8The amplitude control loop consists of signal demodulation, a PI controller, and a distribution control quantity. The process is as follows: the signal demodulation module calculates parameter E based on the reference signal; the PI controller compares the calculated parameter E with the set capability value to control the magnitude of the drive voltage; and the distribution control quantity allocates the voltage control quantity to the electrodes. Specifically, the amplitude control loop process is as follows: the total energy E of the current hemispherical resonant gyroscope is obtained through signal demodulation, and E is compared with the set energy value. The resulting error signal is used as the control signal for the PI controller to control the magnitude of the drive voltage. After obtaining the drive voltage amplitude U0, it is compared with the drive frequency ω generated by the frequency-phase tracking loop and the gyroscope output precession angle. Synthesize 0° electrode axis drive signal 45° electrode axis drive signal Two signals are applied to the hemispherical resonator gyroscope, thereby controlling the amplitude of the hemispherical resonator's vibration.

[0167] Among them, see Figure 9 The quadrature control loop consists of signal demodulation, a PI controller, and a distribution control quantity. The process is as follows: the signal demodulation module calculates parameters E and Q based on the reference signal, and then calculates parameter q. The PI controller compares the calculated parameter q with the set value q = 0, controlling the magnitude of the drive voltage. The distribution control quantity then distributes the voltage control quantity to the electrodes. Specifically, the quadrature control loop process involves: the signals output from the 0° and 45° electrode axes are demodulated and combined, and the result is obtained through parameter Q = 2(C...). x S y -C y S x And the following formula is used as the decision quantity for the orthogonal control loop:

[0168]

[0169] The value obtained from the above formula is the vibration amplitude of the harmonic oscillator on the orthogonal axis. The orthogonal vibration amplitude is reduced to zero by PI control.

[0170] The PI controller parameters described in the above loops are different and need to be adjusted according to the actual situation to achieve the following objectives: the attenuation ratio is best between 4 and 10, that is, the ratio of the first two peaks of the response curve is between 4 and 10; the steady-state error is close to 0; and the faster the system response, the better.

[0171] S4, in full-angle mode, does not require force feedback control of the gyroscope; see [link / reference]. Figure 10 The specific process is as follows: Signal demodulation is used to decode the reference signal to obtain key parameters R and S, which are then used to calculate the output precession angle. Based on the calculated sine parameter S and cosine parameter R of the hemispherical resonator's precession angle, the precession angle of the hemispherical resonator is calculated using the following formula:

[0172]

[0173] in, R is the precession angle of the hemispherical resonant gyroscope, and S is the cosine parameter of the precession angle of the hemispherical resonant gyroscope.

[0174] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for precise control of a full-angle mode hemispherical resonator gyroscope, characterized in that, Includes the following steps: S1: The eight electrodes of the hemispherical resonant gyroscope are grouped in time sequence using an eight-electrode time-division control algorithm to form driving electrodes and detection electrodes; at the same time, the detection electrodes use the eight-electrode time-division control algorithm to determine the x and y signals of the hemispherical resonant gyroscope. S2: Obtain the x and y signals from the hemispherical resonant gyroscope and synchronize the resonant frequency to obtain the synchronized x and y signals; S3: The synchronized x signal is subjected to zero-crossing comparison to obtain a zero-crossing comparison signal. The phase tracker outputs a local carrier using the CORDIC algorithm based on the zero-crossing comparison signal. At the same time, the synchronized x signal and the synchronized y signal are subjected to A / D sampling processing to obtain a digital signal. S4: Based on the local carrier and the digital signal, the local carrier and the digital signal are multiplied using the CORDIC algorithm and then demodulated to obtain the demodulated signal; S5: Based on the demodulated signal, an error feedback control signal is obtained, and the error feedback control signal is used to realize the time-division control of the hemispherical resonator gyroscope in full-angle mode; Simultaneously, the precession angle is output based on the demodulated signal; In S4, the demodulated signal includes: orthogonal axis amplitude information. Harmonic oscillator vibration energy information Harmonic oscillator frequency splitting phase difference information The cosine parameter R of the precession angle of the hemispherical resonant gyroscope and the sine parameter S of the precession angle of the hemispherical resonant gyroscope; The error feedback control signal includes a phase error signal, an amplitude error signal, and a quadrature error signal; In S5, the step of outputting the precession angle based on the demodulated signal specifically includes: Based on the cosine parameter R and sine parameter S of the precession angle of the hemispherical resonant gyroscope, the precession angle of the hemispherical resonant gyroscope can be obtained by the following formula (39). （39） in, R is the precession angle of the hemispherical resonant gyroscope, and S is the cosine parameter of the precession angle of the hemispherical resonant gyroscope.

2. The precise control method for a full-angle mode hemispherical resonator gyroscope according to claim 1, characterized in that, In S1, the eight electrodes include: a 0° electrode, a 90° electrode, a 180° electrode, a 270° electrode, a 45° electrode, a 135° electrode, a 225° electrode, and a 315° electrode.

3. The precise control method for a full-angle mode hemispherical resonator gyroscope according to claim 2, characterized in that, In S1, the driving electrode includes: and The detection electrode includes: and ; It consists of a 0° electrode and a 90° electrode. It consists of 45° and 135° electrodes. It consists of 180° electrodes and 270° electrodes. It consists of a 225° electrode and a 315° electrode.

4. The precise control method for a full-angle mode hemispherical resonator gyroscope according to claim 1, characterized in that, In S5, obtaining the error feedback control signal based on the demodulated signal specifically includes: The frequency-phase control loop splits the phase difference information based on the resonator frequency. The phase error signal is obtained; The amplitude control loop is based on the vibration energy information of the harmonic oscillator. The amplitude error signal is obtained; The orthogonal control loop uses the orthogonal axis amplitude information The orthogonal error signal is obtained.

5. The precise control method for a full-angle mode hemispherical resonator gyroscope according to claim 4, characterized in that, In S5, the step of using the error feedback control signal to realize the time-division control of the hemispherical resonator gyroscope in full-angle mode includes the following steps: the frequency-phase control loop tracks the resonant frequency of the resonator in real time according to the phase error signal, and uses the phase-locked loop to generate a reference signal with the same frequency and phase for the signal calculation of the detection electrode and the signal control quantity allocation of the driving electrode.

6. The precise control method for a full-angle mode hemispherical resonator gyroscope according to claim 4, characterized in that, In S5, the step of using the error feedback control signal to realize the time-division control of the hemispherical resonator gyroscope in full-angle mode further includes the following steps: the amplitude control loop adjusts the voltage of the driving electrode according to the amplitude error signal to control the amplitude of the hemispherical resonator gyroscope.

7. The precise control method for a full-angle mode hemispherical resonator gyroscope according to claim 4, characterized in that, In S5, the step of using the error feedback control signal to realize the time-division control of the hemispherical resonant gyroscope in full-angle mode further includes the following steps: the orthogonal control loop uses PI control to reduce the amplitude of the orthogonal axis vibration to zero according to the orthogonal error signal, and performs orthogonal control on the hemispherical resonant gyroscope.

8. A precise control system for a full-angle mode hemispherical resonator gyroscope, characterized in that, A precise control method for a full-angle mode hemispherical resonator gyroscope according to any one of claims 1 to 7 includes: An eight-electrode time-division control module is used to group the eight electrodes of a hemispherical resonant gyroscope in time sequence using an eight-electrode time-division control algorithm to form driving electrodes and detection electrodes; at the same time, the detection electrodes use the eight-electrode time-division control algorithm to determine the x and y signals of the hemispherical resonant gyroscope. The resonant frequency synchronization module is used to acquire x and y signals from the hemispherical resonant gyroscope and synchronize the resonant frequency to obtain synchronized x and y signals. The zero-crossing comparison and A / D sampling module is used to perform zero-crossing comparison on the synchronized x signal to obtain a zero-crossing comparison signal. The phase tracker outputs a local carrier using the CORDIC algorithm based on the zero-crossing comparison signal. At the same time, the synchronized x signal and the synchronized y signal are subjected to A / D sampling processing to obtain a digital signal. The signal demodulation module is used to multiply the local carrier and the digital signal using the CORDIC algorithm and then demodulate them to obtain the demodulated signal. The control loop module is used to obtain an error feedback control signal based on the demodulated signal, and to use the error feedback control signal to realize time-division control of the hemispherical resonator gyroscope in full-angle mode; at the same time, it outputs the precession angle based on the demodulated signal.

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