A high-vacuum-degree resonator Q value test system and test method

Abstract

This invention pertains to inertial navigation technology and relates to a Q-value testing system and method for high-vacuum resonators. The testing system includes: a sinusoidal excitation signal on / off switch, an AC excitation signal source, a DC high-voltage excitation on / off switch, a high-voltage voltage source, a mode selection switch, a resonator vibrating mass block, comb teeth on the left and right fixed ends of the resonator, a charge amplifier, a dedicated data processing unit, and a dedicated shielding shell. The testing method includes the following steps: Step 1, installation of the high-vacuum resonator; Step 2, mode setting; Step 3, after completing the resonator drive, disconnecting either the sinusoidal excitation signal on / off switch or the DC high-voltage excitation on / off switch, allowing the resonator to enter a natural decay state; Step 4, calculation. This invention has the advantages of being economical, practical, simple, and reliable, and can effectively and accurately measure the Q-value of high-vacuum resonators.

Description

Technical Field

[0001] This invention pertains to inertial navigation technology and relates to a Q-value testing system and method for high-vacuum resonators. Background Technology

[0002] Silicon micromechanical gyroscopes are emerging inertial sensing devices fabricated using semiconductor processing technology on thin silicon wafers. However, silicon is a thermosensitive material, and many of its properties are significantly affected by temperature. A gyroscope is a complex system, requiring an internal analysis to study the impact of temperature changes on each component and subsequently implement temperature compensation for its output. This study analyzes the temperature characteristics of the micromechanical meter head and its influence on the head's resonant frequency and Q value, thereby analyzing the key parameters of the entire gyroscope and providing theoretical and experimental basis for temperature compensation in silicon micromechanical gyroscopes. The Q value, as the most important indicator of a resonator, is crucial for accurate measurement. Because the resonator's vibration displacement is very small in its resonant state, the resulting electrical signal is also very weak and susceptible to interference from the surrounding environment, making accurate and reliable measurement difficult. This makes it challenging to provide effective design references for resonator fabrication and design. Existing testing methods suffer from drawbacks such as a lack of dedicated testing instruments, complex testing methods, and expensive required equipment. Summary of the Invention

[0003] The technical problem to be solved by the present invention is to provide a Q-value testing system for high-vacuum resonators that can meet the Q-value testing requirements of silicon micro resonators.

[0004] The technical solution adopted in this invention is: a Q-value testing system for high-vacuum resonators, characterized in that the system comprises:

[0005] —The sinusoidal excitation signal on / off switch 1 is connected to the AC excitation signal source 2 and the mode selection switch 5. It is used to select the sinusoidal drive signal with the same frequency as the resonant frequency. When not selected, it is grounded.

[0006] — AC excitation signal source 2 is connected to sinusoidal excitation signal on / off switch 1; the output frequency of the AC excitation signal source can be set to select an AC excitation signal with the same frequency as the resonator;

[0007] —DC high voltage excitation on / off switch 3, connected to high voltage source 4, is used to select high voltage electrostatic pull force, and is connected to power supply ground when not selected;

[0008] ——High voltage source 4, a DC voltage source used to generate high electrostatic pulling force;

[0009] —Mode selection switch 5 is connected to sinusoidal excitation signal on / off switch 1, DC high voltage excitation on / off switch 3, and resonator left fixed end comb 7, and is used to select whether the Q value test mode is AC excitation or DC electrostatic pull.

[0010] —The resonator's vibrating mass block 6 is the movable part of the resonator;

[0011] —The comb teeth 7 on the left fixed end of the resonator are connected to the mode selection switch 5 and together with the vibrating mass block 6 of the resonator, they generate driving electrostatic force.

[0012] —The right fixed end comb tooth 8 of the resonator is connected to the charge amplifier 9, and together with the resonator vibrating mass block 6, it generates a weak electrical signal;

[0013] —The charge amplifier 9, connected to the right fixed end comb tooth 8 of the resonator and the dedicated data processing unit 10, is an operational amplifier with ultra-low offset current and ultra-high amplification factor.

[0014] —A dedicated data processing unit 10, connected to the charge amplifier 9, is used to calculate the Q value of the resonator;

[0015] —Special shielding shell 11, a specially made metal shell used to shield external interference electromagnetic signals.

[0016] A testing method using the above-mentioned Q-value testing system, characterized by the following steps:

[0017] Step 1, High Vacuum Resonator Installation: Open the special shielding shell 11, install the high vacuum resonator whose Q value is to be tested inside the special shielding shell 11, and make the connection for driving and testing.

[0018] Step 2, Mode Setting: Select either AC drive or high-voltage DC drive for the resonator via mode selection switch 5;

[0019] Step 3: After driving the resonator, disconnect the sinusoidal excitation signal on / off switch 1 or the DC high voltage excitation on / off switch 3 to allow the resonator to enter a natural decay state.

[0020] Step 4, Calculation: Turn on the dedicated data processing unit 10 to measure and calculate the attenuation signal generated by the resonator, and calculate the true Q value of the high vacuum resonator.

[0021] The advantages and beneficial effects of this invention are as follows: The Q-value testing system and method for high-vacuum resonators of this invention adopts the attenuation method to obtain a weak electrical signal under single-sided excitation and single-sided detection; then the signal is amplified by an operational amplifier with ultra-low offset current and ultra-high amplification factor; finally, the Q-value is calculated by the relationship between amplitude and frequency. This invention has the advantages of being economical, practical, simple and reliable. Experiments have proven that it can effectively and accurately measure the Q-value of high-vacuum resonators and can replace the Q-value testing system that previously required a large number of expensive and complex testing equipment. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the Q-value testing system for high-vacuum resonators in this invention;

[0023] Figure 2 This is a schematic diagram of the charge amplifier in this invention;

[0024] Figure 3 This is the output waveform generated by the high-voltage excitation method in this invention;

[0025] Figure 4 This is the output waveform generated by the sinusoidal excitation method in this invention;

[0026] Among them, 1-sine excitation signal on / off switch, 2-AC excitation signal source, 3-DC high voltage excitation on / off switch, 4-high voltage source, 5-mode selection switch, 6-resonator vibrating mass block, 7-resonator left fixed end comb teeth, 8-resonator right fixed end comb teeth, 9-charge amplifier, 10-dedicated data processing unit, 11-dedicated shielding shell. Detailed Implementation

[0027] The specific embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0028] from Figure 1 As can be seen, the Q-value testing system consists of an AC excitation signal source 3 and a high-voltage voltage source 4 in the driving section, a charge amplifier 9 in the detection section, and a dedicated data processing unit 10 for Q-value calculation. The driving section is divided into AC drive and DC drive modes. For the AC drive mode, the resonant frequency of the resonator needs to be determined first by frequency sweeping. An AC drive voltage is applied to the resonator, and the drive frequency at which the resonator reaches its maximum drive amplitude is the resonant frequency. For the DC drive mode, the applied DC voltage must ensure sufficient electrostatic force without damaging the resonator. The drive voltage is gradually increased, and the output of the charge amplifier is observed until the initial amplitude reaches a sufficient height. The dedicated shielding shell 11 is a cuboid made of aluminum alloy with connecting holes, which ensures effective shielding while facilitating the installation of the resonator and the connection of leads. To minimize the noise of the high-gain charge amplifier, a battery power supply is used. The output processing 10 includes three parts: ADC analog-to-digital conversion, data storage, and data processing.

[0029] The following is a specific embodiment of the testing method used in this invention.

[0030] 1. Use a signal generator as the AC drive excitation source: Set the DC bias voltage to 2.5V, the AC peak-to-peak voltage to 5V, the estimated resonant frequency of the resonator to 8KHz, and the sweep frequency range to 6-10KHz.

[0031] 2. Use a standard DC power supply as the DC drive excitation source, and set the DC drive voltage to be linearly adjustable from 30V to 90V;

[0032] 3. Two 9V high-voltage batteries are used as the power supply for the charge amplifier, according to... Figure 2 Conduct circuit construction;

[0033] 4. Arrange the resonance and charge amplifier according to Figure 1 Connect the wires and install them into a dedicated shielding housing;

[0034] 5. With mode selection switch 5 set to AC excitation mode, and sine excitation signal on / off switch 1 set to the signal output position connected to the signal generator, observe the analog detection signal while gradually increasing the sweep voltage to find the frequency where the maximum value of the analog detection signal is 7.9kHz. Figure 4 As shown;

[0035] 6. When the sinusoidal excitation signal on / off switch 1 is in the grounded state, the resonator will attenuate as follows: Figure 3 As shown, the dedicated data processing module processes the analog attenuation signal and calculates the Q value to be 59910.

[0036] 7. With the DC high-voltage excitation on / off switch 3 in the grounded state, adjust the DC drive voltage to 50V, and then place the DC high-voltage excitation on / off switch 3 in the 50V connection position. After 10 seconds, return it to the grounded state. The high-vacuum resonator will then undergo attenuation. Figure 3 As shown, the dedicated data processing module processes the analog attenuation signal and calculates the Q value to be 57803.

Claims

1. A Q-value testing system for a high-vacuum resonator, characterized in that: The system includes: —The sinusoidal excitation signal on / off switch (1) is connected to the AC excitation signal source (2) and the mode selection switch (5) to select the sinusoidal drive signal with the same frequency as the resonant frequency. When not selected, it is grounded. —An AC excitation signal source (2) is connected to a sinusoidal excitation signal on / off switch (1); the output frequency of the AC excitation signal source can be set to select an AC excitation signal with the same frequency as the resonator; -- DC high voltage excitation switch (3) is connected to the high voltage source (4) to select the high voltage electrostatic pull force. When not selected, it is connected to the power supply ground. —High voltage source (4), DC voltage source used to generate high voltage electrostatic pulling force; —The mode selection switch (5) is connected to the sinusoidal excitation signal on / off switch (1), the DC high voltage excitation on / off switch (3), and the comb tooth (7) of the left fixed end of the resonator, and is used to select whether the Q value test mode is AC excitation or DC electrostatic pull. —The vibrating mass block (6) of the resonator is the movable part of the resonator; —The left fixed end comb (7) of the resonator is connected to the mode selection switch (5) and together with the resonator vibrating mass block (6) generates driving electrostatic force; —The right fixed end comb (8) of the resonator is connected to the charge amplifier (9) and together with the resonator vibrating mass block (6) generates a weak electrical signal; —The charge amplifier (9), connected to the right fixed end comb tooth (8) of the resonator and the dedicated data processing unit (10), is an operational amplifier with ultra-low offset current and ultra-high amplification factor; —A dedicated data processing unit (10) is connected to the charge amplifier (9) for processing the Q value of the resonator; ——Special shielding shell (11), a special metal shell used to shield external interference electromagnetic signals.

2. A testing method using the Q-value testing system of claim 1, characterized by the following steps: Step 1, High Vacuum Resonator Installation: Open the special shielding shell (11), install the high vacuum resonator whose Q value is to be tested inside the special shielding shell (11), and connect the drive and test wires. Step 2, Mode setting: Select either AC drive or high voltage DC drive for the resonator electrostatic drive mode by using the mode selection switch (5); Step 3: After driving the resonator, disconnect the sinusoidal excitation signal on / off switch (1) or disconnect the DC high voltage excitation on / off switch (3) to allow the resonator to be in a natural decay state. Step 4, Calculation: Turn on the dedicated data processing unit (10) to measure and calculate the attenuation signal generated by the resonator, and calculate the true Q value of the high vacuum resonator.

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