CN114152380B - A fast-response two-stage pendulum device for micronew level thrust test - Google Patents

Abstract

The invention discloses a quick response secondary pendulum device for a micro-Newton thrust test, which comprises: the system comprises a suspension module, a micro-thruster, a first accelerometer, a second accelerometer, a swing frame and a monitoring module; the suspension module is connected with the swing frame, and the swing frame can rotate around the horizontal direction or the vertical direction; the micro-thruster applies horizontal thrust to the swing frame; the first accelerometer and the second accelerometer are arranged at the upper end and the lower end of the swing frame and are used for differentially measuring the acceleration of the swing frame; the monitoring module monitors the displacement change of the swing frame and provides an angle reference, and the proportional coefficient of the displacement and the angle change of the swing frame is calibrated. The torsion pendulum and the accelerometer are adopted to jointly test the thrust of the micro-thruster, the eigenperiod of the torsion pendulum is in the second order, the eigenperiod of the accelerometer reaches the microsecond order, and the micro-thruster has better high-frequency performance; the thrust change can be quickly responded while the thrust of the micro propeller is measured with high precision; simple structure, measurement accuracy is high, and response speed is fast and convenient operation.

Description

A fast-response two-stage pendulum device for micronew level thrust test

technical field

The invention belongs to the technical field of thrust measurement of micro-thrusters, and more specifically relates to a fast-response two-stage pendulum device for micro-North level thrust testing.

Background technique

With the development of science and technology, human beings have more and more intense demands on space exploration, and higher requirements are put forward for the drag-free control of satellites. In order to improve the precision of drag-free control, the resolution of the micro-propulsion system is required to reach micronewton or even submicronewton level. At the same time, high requirements are also put forward for the rapid response of the micro-thruster. When the micro-thruster is working, its thrust rise time can be at least tens of milliseconds. Therefore, it is necessary to study a thrust measurement device of micro-bovine level micro-thruster with high precision and fast response speed to meet the increasing demand of scientific and technological development.

Contents of the invention

Aiming at the defects of the prior art, the object of the present invention is to provide a fast-response two-stage pendulum device for micro-new level thrust testing, aiming at solving the problem of the rigidity of the test device in the prior art in order to achieve the purpose of high-precision measurement. Small enough to cause problems with long cycle times and slow response times for test fixtures.

The invention provides a fast-response two-stage pendulum device for micro-Newton level thrust testing, comprising: a suspension module, a micro-propeller, a first accelerometer, a second accelerometer, a pendulum frame and a monitoring module; the suspension The module is connected with the pendulum frame, and the pendulum frame can rotate around the horizontal direction or the vertical direction; the micro-propeller is used to apply horizontal thrust to the pendulum frame; the first accelerometer and the The second accelerometer is arranged on the upper end and the lower end of the pendulum frame, and is used to differentially measure the acceleration of the pendulum frame; the monitoring module is used to monitor the displacement change of the pendulum frame, and provide an angle reference, and compare the displacement of the pendulum frame with the The coefficient between the angle changes is calibrated.

Furthermore, the suspension module is a torsion wire or a reed. When the suspension module is a twisted wire, the twisted wire is made of metal or glass, and the twisted wire can be cylindrical; when the suspension module is a reed, the reed is two thin rectangular strips.

Among them, when the suspension module is a twisted wire, the swing frame can be a rectangular structure, and the swing frame rotates around a vertical axis; when the suspension module is a reed, the swing frame can be a sun-shaped structure, and the swing frame rotates around a horizontal The shaft turns.

Furthermore, the monitoring module includes: a capacitive displacement sensing unit, a reflector, an autocollimator and a data acquisition and processing unit; when the suspension module is a reed, the capacitive displacement sensing unit is arranged on the swing frame At the bottom, the reflector is arranged at the lower end of the swing frame; when the suspension module is twisted wire, there is no capacitive displacement sensing unit, and the reflector is arranged at the middle of the side of the swing frame. The autocollimators are all placed outdoors. The capacitive displacement sensing unit measures the displacement change caused by the rotation of the pendulum frame. The mirror is used to reflect the incident light of the autocollimator, and the angle change of the pendulum frame can be obtained after the autocollimator receives the reflected light, and the angle change value of the pendulum frame measured by the autocollimator (that is, the pendulum angle) can be obtained The displacement and swing angle coefficient of the capacitive displacement sensing unit is obtained, and the displacement of the capacitive displacement sensing unit is converted into a swing angle by using this coefficient. The data collection and processing unit is used to collect the displacement signal output by the capacitive displacement sensing unit and the angle signal output by the autocollimator.

Wherein, the capacitive displacement sensing unit includes: a swing frame capacitor plate and a fixed capacitor plate; the fixed capacitor plate is fixed to the vacuum container, and the swing frame capacitor plate is fixed to the swing frame.

As an embodiment of the present invention, the fast-response two-stage pendulum device further includes: a micro-propeller bracket, which is used to install the micro-propeller on the pendulum frame.

As an embodiment of the present invention, the fast-response two-stage pendulum device further includes: a calibration bracket, on which a calibration mass of known mass is placed to calibrate the thrust of the micro-propeller.

In the embodiment of the present invention, the fast-response two-stage pendulum device further includes: a counterweight and an electromagnetic force unit, the counterweight is used to balance the gravity of the micro-propeller; the magnetic force unit is used to accept the known electromagnetic force applied by the outside force.

Through the above technical scheme conceived by the present invention, compared with the prior art, since the thrust of the micro-propeller is tested jointly by the torsion pendulum and the accelerometer, the eigenperiod of the torsion pendulum is on the order of seconds, and the eigenperiod of the accelerometer can reach the order of ms , has better high-frequency performance; it can quickly respond to thrust changes while measuring the thrust of the micro-thrust with high precision.

Description of drawings

Fig. 1 is the front view of the fast-response two-stage pendulum device used in the micro-New level thrust test provided by the embodiment of the present invention in the horizontal axis torsion pendulum working mode;

Fig. 2 is a side view of the fast-response two-stage pendulum device used in the micro-New level thrust test provided by the embodiment of the present invention in the horizontal axis torsion pendulum working mode;

Fig. 3 is a structural diagram of a fast-response two-stage pendulum device used for micro-New level thrust testing provided by an embodiment of the present invention in the horizontal axis torsion pendulum working mode;

Fig. 4 is a front view of the fast-response two-stage pendulum device used in the microN level thrust test provided by the embodiment of the present invention in the vertical axis torsion pendulum working mode;

Fig. 5 is a side view of the fast-response two-stage pendulum device used in the microN level thrust test provided by the embodiment of the present invention in the vertical axis torsion pendulum working mode;

Fig. 6 is a structural diagram of a fast-response two-stage pendulum device used for microN level thrust testing provided by an embodiment of the present invention in the working mode of vertical axis torsion pendulum.

Each part name is explained below:

1 is the bracket, 2 is the suspension module, 3 is the calibration bracket, 4 is the micro propeller, 5 is the mirror, 6 is the first accelerometer, 7 is the second accelerometer, 8 is the pendulum frame, 9 is the micro propeller Support, 10 is a capacitor plate, 11 is a counterweight, and 12 is an electromagnetic force unit.

Detailed ways

In order to make the object, technical solution and advantages of the present invention clearer, the present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described here are only used to explain the present invention, not to limit the present invention.

The invention provides a fast-response two-stage pendulum device for micro-North-level thrust testing, which can solve the contradiction between the high-precision thrust of the micro-propulsion and the fast-response test, and use the high-frequency accelerometer to quickly measure the micro-propulsion force For the acceleration on the pendulum, the acceleration of the pendulum frame produced by the micro-propeller is differentially measured through the accelerometers at different positions, and the thrust of the micro-thruster is obtained according to the transfer function, and the pendulum is measured by the capacitive displacement sensing unit and the autocollimator The angular change of the angle can realize the rapid dynamic measurement of the thrust while measuring the thrust with high precision.

The main body of the device provided by the embodiment of the present invention is a pendulum structure, specifically a bracket, a suspension module, a pendulum frame and a monitoring module; wherein, the pendulum frame is suspended by the suspension module, and the pendulum frame is under the action of gravity or the restoring force of the torsion wire It will do periodic reciprocating motion. The micro-propeller is installed on the pendulum frame through the micro-propeller bracket. By adjusting the position of the micro-propeller fixing bracket, the attitude of the pendulum frame can be adjusted. When the thrust of the micro-propeller acts, the pendulum The acceleration of the frame will change, and the thrust torque will reach equilibrium with the gravitational torque or the torque of the torsion wire at the new equilibrium position. At this time, the equilibrium position of the pendulum frame will change. According to the displacement signal and From the angle signal measured by the autocollimator, the magnitude of the measured thrust can be obtained. When the thrust is applied by the micro-thruster, the accelerometer can monitor the acceleration change of the pendulum frame in real time, and the thrust of the micro-thrust can be obtained dynamically through the transfer function.

The capacitive displacement sensing circuit outputs the measured displacement change to the outside in the form of voltage, and according to the angle change of the pendulum frame (that is, the swing angle) monitored by the high-precision autocollimator, the voltage obtained by the capacitive displacement sensing circuit is high-voltage. The precision coefficient calibration can directly convert the differential voltage signal obtained by the displacement sensing circuit into a swing angle signal.

In the present invention, a high-frequency accelerometer is placed on the pendulum to directly measure the acceleration of the pendulum frame, and at the same time, the angle change of the pendulum frame is accurately measured (specifically, the capacitive displacement transmission can be measured according to the pendulum angle detected by the high-precision autocollimator. The voltage obtained by the sensing circuit can be calibrated with high-precision coefficients, and the differential voltage signal obtained by the displacement sensing circuit can be directly converted into a swing angle signal, that is, the angle can be accurately measured). The parameters of the pendulum are calibrated, and the parameters of the pendulum are calibrated by applying electromagnetic force in the case of vertical axis torsion pendulum. Then the size of the thrust and the dynamic change of the thrust are obtained according to the transfer function. Due to the high frequency of the accelerometer, the response speed to the thrust of the micro-thrust is very fast, which can reach tens of milliseconds, which meets the requirements of the dynamic response test of the micro-thrust. Through the differential measurement of two accelerometers, the influence of external vibration and gravitational acceleration and other interference factors on the acceleration to be measured can be reduced. The whole installation and testing process is simple to operate and easy to use.

As shown in Figures 1-6, the fast-response two-stage pendulum device for micronew level thrust test provided by the embodiment of the present invention includes: a suspension module 2, a micro propeller 4, a first accelerometer 6, and a second accelerometer 7 , the pendulum frame 8 and the monitoring module; the micro propeller 4 is used to apply a horizontal thrust to the pendulum frame 8; the first accelerometer 6 and the second accelerometer 7 are arranged at different positions on the pendulum frame 8 for differential measurement The acceleration of the pendulum frame 8 reduces the impact of external vibration and gravitational acceleration on the pendulum frame 8, and measures the dynamic performance of the micro-propeller; the suspension module 2 is connected with the pendulum frame 8, and the pendulum frame 8 can rotate around the horizontal direction or Rotate in the vertical direction; the monitoring module is used to monitor the displacement change of the pendulum frame 8 and provide an angle reference to calibrate the proportional coefficient between the displacement change measured by the capacitive displacement sensing unit and the angle change of the pendulum frame.

In the embodiment of the present invention, the suspension module 2 can be a torsion wire or a reed. When the suspension module 2 is a reed, the pendulum frame 8 rotates around the horizontal direction and forms a horizontal axis torsion; when the suspension module 2 is a torsion wire, The pendulum frame 8 rotates around the vertical direction and constitutes a vertical axis torsion. Among them, the horizontal axis torsion pendulum is the general term for the pendulum that twists around the horizontal axis, and the typical form is the compound pendulum; the vertical axis torsion pendulum is the general term for the pendulum that twists around the vertical axis, and the typical form is the torsion balance.

As an embodiment of the present invention, the suspension module 2 can be a reed or a torsion wire. When the suspension module 2 is a torsion wire, the torsion wire can be made of metal or glass material and is cylindrical, and the swing frame rotates around a vertical axis; When the suspension module 2 is a reed, the reed can be two thin rectangular strips, the swing frame rotates around a vertical axis, the upper end of the suspension module is fixedly connected with the support, and the lower end is fixedly connected with the swing frame 8.

As an embodiment of the present invention, the reeds in the suspension module 2 can be made of metal materials with a thickness of tens to hundreds of microns; The thrust range and pendulum mass of the micro-propeller to be tested are adapted to the diameter of the torsion wire.

The fast-response two-stage pendulum device provided by the embodiment of the present invention can be connected through the suspension module. In the horizontal axis torsion pendulum mode, the parameters such as the period and moment of inertia of the entire device can be measured by placing a calibration mass on the calibration bracket on the pendulum frame 8. . In the vertical axis torsion pendulum working mode, the cycle, moment of inertia and other parameters of the whole device are calibrated by applying known electromagnetic force. By combining the known parameters with the angle change measured by the capacitive displacement sensing unit and the acceleration of the pendulum frame 8 measured by the accelerometer, the magnitude and dynamic performance of the thrust can be obtained according to the transfer function.

As an embodiment of the present invention, the swing frame 8 can be made of metal material or glass material, and its shape can be processed and modified according to its installation parts. In the horizontal axis torsional pendulum working mode, it is a Japanese font, and in the vertical axis torsional pendulum working mode, it is a rectangle.

Specifically, the first accelerometer 6 and the second accelerometer 7 are installed on the pendulum frame 8 to differentially measure the acceleration of the pendulum.

In the embodiment of the present invention, the electromagnetic force unit is composed of a magnet and a damping disc, which is only used in the vertical axis working mode and passes through the suspension module to increase the damping of the swing frame; The magnet of the frame 8 is used to provide damping to the swing of the pendulum.

In the embodiment of the present invention, the monitoring module includes: a capacitive displacement sensing unit, a mirror 5, an autocollimator, and a data acquisition and processing unit, including: a capacitive displacement sensing unit, a mirror, an autocollimator, and a data acquisition and processing unit unit, when the suspension module is a reed, the capacitive displacement sensing unit is arranged at the bottom of the swing frame, and the reflector is arranged at the lower end of the swing frame; when the suspension module is a twisted wire, there is no As for the capacitive displacement sensing unit, the reflector is arranged at the middle position of the side of the pendulum frame. The autocollimators are all placed outdoors. The capacitive displacement sensing unit measures the displacement change caused by the rotation of the pendulum frame. The reflector is used for the incident light of the autocollimator, and the angle change of the pendulum frame can be obtained after the autocollimator receives the reflected light, and the displacement of the capacitive displacement sensing unit can be obtained by using the angle change value of the pendulum frame measured by the autocollimator and the pendulum angle coefficient, which is used to convert the displacement of the capacitive displacement sensing unit into the angle change value of the pendulum frame. The data collection and processing unit is used to collect the displacement signal output by the capacitive displacement sensing unit and the angle signal output by the autocollimator.

The displacement change of the pendulum frame 8 is obtained through the capacitive displacement sensing unit and expressed in the form of voltage. The autocollimator can provide an angle reference, and the coefficient between the voltage and the angle change is calibrated through the mirror 5 . The acceleration change of the pendulum frame 8 is obtained through the difference between the first accelerometer 6 and the second accelerometer 7, and the combination of the three can measure the thrust of the micro propeller with high precision and quick response.

Wherein, the capacitive displacement sensing unit is composed of a swing frame capacitor plate 10 and a fixed capacitor plate, and is used for monitoring the movement displacement of the swing frame frame 8 . The capacitor pole plate of the pendulum frame is fixed on the bottom end of the pendulum frame, and the fixed capacitor pole plate is fixedly connected with the vacuum container. The rotation of the pendulum frame causes the distance between the pendulum capacitor plate and the fixed capacitor plate to change, which in turn causes the capacitance of the capacitive displacement sensing unit to change, and the capacitive displacement sensing unit uses the measured capacitance change to obtain the displacement change of the pendulum frame .

In the embodiment of the present invention, the fast-response two-stage pendulum device also includes: a calibration bracket 3, a micro-propeller bracket 9, a counterweight 11, and an electromagnetic force unit 12, and a calibration mass with a known mass is placed on the calibration bracket 3 to use To calibrate the thrust of the micro propeller; the counterweight 11, when it is in the vertical axis working mode, is on one side of the pendulum frame and at the opposite end to the micro propeller, and is used to balance the gravity of the micro propeller 4 against the pendulum The influence of frame tilt attitude; when it is the horizontal axis working mode, it is in the middle of the swinging frame, and is used to balance the influence of the gravity of the micro propeller 4 on the elastic coefficient of the swinging frame; the magnetic force unit 12, when it is the vertical axis working mode , which is located on the side of the pendulum frame and at the opposite end to the micro-propeller, is used to generate a known horizontal thrust, combined with the measured angle change value of the pendulum frame, to measure the elastic coefficient of the pendulum frame. When working in the horizontal axis mode, without a magnetic unit, the gravity method is used to measure the elastic coefficient of the pendulum frame;

Wherein, the micro-propeller 4 is installed on the pendulum frame 8 through the micro-propeller bracket 9. When the micro-propeller 4 exerts thrust, the motion state of the pendulum frame 8 will change, and rotate around the suspension module, causing the capacitive displacement sensing unit capacitance The capacitance displacement sensing unit measures the capacitance variation to obtain the displacement variation of the pendulum frame.

Micro propeller support 9 can adjust the position and attitude of micro propeller 4, can adjust the attitude of pendulum frame 8 by the position of regulating micro propeller 4, make it vertical, reduce micro propeller and pendulous frame frame gravitational component to The coupling of the thrust measurement value of the micro-thruster reduces the error of the thrust measurement value.

In the embodiment of the present invention, the fast-response two-stage pendulum device also includes: a fixed bracket 1, which is fixed and used to fix the entire device in the vacuum container.

Wherein, the lower end of the pendulum frame 8 is provided with a micro propeller support 9, and the attitude of the pendulum frame 8 can be adjusted by adjusting the position of the micro propeller support 9. A mirror 5 is fixed on the pendulum frame 8, and the movement angle of the pendulum frame 8 can be measured and calibrated by an autocollimator. Two accelerometers are installed at different positions on the pendulum frame 8, which can differentially measure the acceleration of the pendulum frame 8. In the horizontal axis torsion pendulum working mode: the lowermost end of the pendulum frame 8 is fixed with a capacitor plate, and the capacitor plate below the pendulum frame 8 is located between the two capacitor plates of the displacement sensing circuit to form a differential capacitance. Can be used for fixing the electric circuit system of trachea and micro-propeller at pendulum frame 8 sides. A calibration bracket is installed in the middle of the front of the pendulum frame 8, and the parameters such as the moment of inertia of the pendulum frame 8 and the size of the thrust can be calibrated by placing a calibration mass on the calibration bracket. In the vertical axis torsion mode of operation: install the circuit system of the gas pipe and the micro-propeller along the vertical axis.

The invention can quickly respond to the change of the thrust of the micro propeller while measuring with high precision, and has good dynamic performance.

The present invention utilizes above-mentioned device to obtain the method for micropropeller thrust, specifically comprises the following steps:

(1) The micro-propeller is installed and adjusted in place, and the swing frame 8 is guaranteed to be vertical through the vertical reference and the reflector.

式中I、λ、K、θ(t)、τ分别表示摆架框8的整体转动惯量、阻尼系数、刚度、摆偏转角度和外力矩，根据公式mgl＝KΔθ或者Fele＝KΔθ，其中g为本地重力加速度，Δθ为摆架框8平衡位置的角度变化量，得到摆架框8的刚度K，通过摆架框8的角度变化拟合出摆架框8 的运动周期T，根据公式K＝4π2I/T2，可以得到摆架框8的转动惯量I，同时根据角度变化量Δθ对应的电容位移传感单元的电压变化量ΔV给出角度与电压之间对应系数。(2) Relevant parameters of the calibration device: in the horizontal axis torsion pendulum mode, place the calibration mass on the calibration bracket, its mass is m, and the distance from the calibration mass to the suspension point is lm, and in the vertical axis torsion pendulum mode, apply the electromagnetic force Fe on the pendulum, and the electromagnetic force is The force arm is le, and the motion equation of the pendulum frame 8 can be expressed as:

In the formula, I, λ, K, θ(t), and τ respectively represent the overall moment of inertia, damping coefficient, stiffness, pendulum deflection angle and external moment of the pendulum frame 8, according to the formula mgl=KΔθ or Fele=KΔθ, where g is The local gravitational acceleration, Δθ is the angular variation of the pendulum frame 8 equilibrium position, the stiffness K of the pendulum frame 8 is obtained, and the motion period T of the pendulum frame 8 is fitted through the angle change of the pendulum frame 8, according to the formula K= 4π2I/T2, the moment of inertia I of the pendulum frame 8 can be obtained, and the corresponding coefficient between the angle and the voltage can be given according to the voltage variation ΔV of the capacitive displacement sensing unit corresponding to the angle variation Δθ.

第二加速度计测得的加速度为

其中θ为摆架框8的运动角度，g为本地重力加速度， l₁和l₂分别为第一加速度计和第二加速度计到转轴的距离。两者之差为

通过差分可消除当地重力加速度对所测得加速度的影响。将这个方程同样进行拉普拉斯变化，

可得到摆架框8系统角度θ到加速度计差分后外界加速度Δa的传递函数

根据角度到推力的传递函数

其中L为微推进器的推力力臂，则加速度到推力的传递函数为

根据传递函数代入参数，将其进行反拉普拉斯变化，得到微推进器推力F随时间t的表达式，

则根据所测加速度和角度可以快速测量推力的值。(3) Test the micro-thruster, the micro-thruster applies thrust, the angle change of the pendulum frame 8 is monitored by the capacitive displacement transmission system and the autocollimator, and the acceleration of the pendulum frame 8 is monitored by the accelerometer. When the accelerometer is horizontally installed on the pendulum frame 8, the accelerometer measures the acceleration in the horizontal direction, and by placing two accelerometers at different positions from the suspension point, the acceleration measured by the first accelerometer is

The acceleration measured by the second accelerometer is

Where θ is the movement angle of the pendulum frame 8, g is the local gravitational acceleration, l ₁ and l ₂ are the distances from the first accelerometer and the second accelerometer to the rotating shaft, respectively. The difference between the two is

The influence of the local gravitational acceleration on the measured acceleration is eliminated by differencing. Applying the same Laplace transformation to this equation,

The transfer function of the pendulum frame 8 system angle θ to the external acceleration Δa after the difference of the accelerometer can be obtained

Transfer function according to angle to thrust

Where L is the thrust arm of the micro propeller, then the transfer function from acceleration to thrust is

Substituting the parameters according to the transfer function, and performing inverse Laplace change to obtain the expression of the thrust F of the micro-thruster with time t,

Then the thrust value can be quickly measured according to the measured acceleration and angle.

In the embodiment of the present invention, the form of a two-stage pendulum is adopted, which can simultaneously measure the acceleration of the pendulum frame 8 and the angle change of the pendulum frame 8, and has the advantages of high precision and fast response. At the same time, it is of great significance to the research and development of micro-thrusters to be able to quickly measure the rising process of the thrust of the micro-thrust and reflect the change of thrust.

In the embodiment of the present invention, the calibration method is specifically:

In the horizontal axis torsion pendulum working mode, the moment is given by measuring the calibration mass and its moment arm, and then the thrust is calibrated by measuring the moment arm of the micro propeller. In the vertical axis torsion pendulum working mode, the electromagnetic force and the electromagnetic force arm are calibrated outside the device, and then the thrust is calibrated by measuring the force arm of the micro propeller.

According to the swing angle monitored by the high-precision autocollimator, the voltage obtained by the capacitive displacement sensing circuit is calibrated with high-precision coefficients.

In the embodiment of the present invention, the gravity torque calibration can be traced to the gravity reference in the horizontal axis torsion mode, and the gravity calibration is not affected by the external environment, and the calibration result is more accurate. In the working mode of vertical axis torsion pendulum, the calibration is carried out by electromagnetic force, which can continuously calibrate the device, which is more convenient.

It is easy for those skilled in the art to understand that the above descriptions are only preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present invention, All should be included within the protection scope of the present invention.

Claims (6)

1. A fast-response secondary pendulum device for micro-new level thrust testing, comprising: a suspension module, a micro-propeller, a first accelerometer, a second accelerometer, a pendulum frame and a monitoring module; The suspension module is connected to the pendulum frame, and the pendulum frame can rotate around the horizontal direction; The micro-propeller is used to apply horizontal thrust to the swing frame; When the pendulum frame rotates around the horizontal direction, the first accelerometer and the second accelerometer are respectively arranged at the upper end and the lower end of the pendulum frame for differentially measuring the acceleration of the pendulum frame; The monitoring module is used to monitor the displacement change of the pendulum frame, provide an angle reference, and calibrate the proportional coefficient between the displacement of the pendulum frame and the angle change; When the suspension module is a reed, the swing frame is a sun-shaped structure, and the swing frame rotates around the horizontal axis; The reeds are in the shape of two rectangular strips. 2. fast response secondary pendulum device as claimed in claim 1, is characterized in that, described monitoring module comprises: capacitive displacement sensing unit, reflecting mirror, autocollimator and data acquisition processing unit; The capacitive displacement sensing unit is used to measure the displacement change caused by the rotation of the pendulum frame; The reflector is used to reflect the incident light of the autocollimator, the angle change of the pendulum frame is obtained after the autocollimator receives the reflected light, and the angle change value of the pendulum frame measured by the autocollimator is used to obtain the capacitive displacement transmission The displacement and swing angle coefficient of the sensing unit, using this coefficient to convert the displacement of the capacitive displacement sensing unit into the angle change value of the pendulum frame; The data collection and processing unit is used to collect the displacement signal output by the capacitive displacement sensing unit and the angle signal output by the autocollimator. 3. The fast-response two-stage pendulum device as claimed in claim 2, wherein when the suspension module is a reed, the capacitive displacement sensing unit is arranged on the bottom of the pendulum frame, and the reflector is arranged at the lower end of the swing frame. 4. The fast-response two-stage pendulum device as claimed in any one of claims 1-3, wherein the fast-response two-stage pendulum device also includes: a micro-propeller bracket for installing the micro-propeller on the swing frame. 5. The fast-response two-stage pendulum device according to any one of claims 1-3, wherein the fast-response two-stage pendulum device also comprises: a calibration bracket, on which a known mass is placed The calibration quality is used to calibrate the thrust of the micro-propeller. 6. The fast-response two-stage pendulum device according to any one of claims 1-3, wherein the fast-response two-stage pendulum device also includes: a counterweight and an electromagnetic force unit, and the counterweight is used to balance the The gravity of the micro-propeller; the magnetic force unit is used to accept the known electromagnetic force applied by the outside world.

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