CN115079737B - Gravitational acceleration modulation device and method - Google Patents

Abstract

The invention discloses a gravitational acceleration modulation device and method. The gravitational acceleration modulation device includes particles, modulation module, vacuum module, capture module, and detection module; the modulation module includes sequentially connected flywheels, rotating shafts, couplings, reducers, motors, three-axis precision translation platforms, and motor supports ; The motor drives the flywheel to periodically move relative to the position through the reducer and the coupling to realize force or acceleration modulation; the vacuum module is used to provide an ultra-high vacuum environment; the capture module uses a magnetic field, light field or electric field to capture particles; the detection module It is used to detect the motion information of particles; the modulation module and the capture module are integrally installed in the vacuum module. The invention utilizes the law of universal gravitation to avoid the influence of mass error, and designs a flywheel structure, which can realize the double frequency modulation of the particle signal, avoid the influence of the inherent frequency noise of the motor itself, and realize the calibration of gravitational acceleration, which can be applied In quantum sensing, precision measurement and other fields.

Description

Gravitational acceleration modulation device and method

technical field

The invention relates to the technical field of gravity or acceleration modulation calibration, in particular to a gravitational acceleration modulation device and method.

Background technique

，首先通过微位移调节机构将标定物体两次加载在标定臂上的不同V型凹槽，通过位移/角度传感器测量的两次摆臂与初始平衡位置相比的偏转角度的差值Δθ，通过计算标定力系数k，标定完成后取走标定物体，摆臂回到初始平衡位置；然后通过待测微推进器产生推力F _x ，通过位移/角度传感器测量摆臂与初始平衡位置相比的偏转角度Δθ _x ，通过计算的标定力系数k，从而实现对待测推力F _x 的标定（CN216207186U—一种纳牛级弱力标定装置）。In the application of weak force and acceleration sensing, optical tweezers technology and magnetic levitation technology in low-pressure gas can measure extremely weak force and acceleration, so there is an important demand in the fields of non-Newtonian gravity verification and ultra-precise navigation. Currently, ng level precision measurement. The existing angular acceleration rotation modulation mechanism usually requires the motor on the base to provide high-frequency jitter drive. In this driving mode, the reaction torque directly acts on the base, making it difficult for the platform to maintain stable accuracy, which in turn leads to measurement calibration errors. At present, it has been proposed that when the base torque motor drives the overall uniform rotation of the platform through the rotating shaft, two rotating platforms with the same inertia are driven by an electromagnetic device to form a periodic relative angular position rotation to realize angular acceleration modulation. The platform has angular momentum changes with the same value and opposite directions, and its synthetic angular momentum variation is close to zero, which makes the reaction torque of the platform as a whole relative to the base also close to zero, thereby suppressing the generation of angular momentum caused by angular acceleration modulation. The reaction torque (CN104578570A—a dynamic disturbance rotation modulation mechanism). Some use weighing measurement calibration, first prepare the standard body, then re-calibrate the center of mass test, and then the signal of the load cell has been processed through comprehensive testing, and has become a digital signal, which is displayed in the control system after the load cell is stressed The test data can be equal to the force of the sensor by multiplying it by a coefficient. This coefficient is called the transfer coefficient of the sensor and is recorded as K. The center of mass measurement is obtained by analyzing the force before and after the reading of the load cell. The sensor coefficient K has nothing to do with the acceleration of gravity, and the measurement of the center of mass has nothing to do with the acceleration of gravity. In actual operation, as long as the calibration process and the product measurement process are at the same place, there is no need to consider Influence of gravitational acceleration (CN105092010A—a weighing sensor coefficient and gravitational acceleration calibration method). A nano-level weak-force calibration device is used for high-precision real-time calibration of horizontal-axis pendulum-type weak-force test benches. The expression of its working principle is

, first, the calibration object is loaded twice on different V-shaped grooves on the calibration arm through the micro-displacement adjustment mechanism, and the difference Δ θ between the deflection angles of the two swing arms compared with the initial equilibrium position measured by the displacement/angle sensor, By calculating the calibration force coefficient k, the calibration object is removed after the calibration is completed, and the swing arm returns to the initial equilibrium position; then the thrust F _x is generated by the micro-propeller to be tested, and the displacement/angle sensor is used to measure the swing arm compared with the initial equilibrium position The deflection angle Δ θ _x , through the calculation of the calibration force coefficient k, thereby realizing the calibration of the thrust F _x to be measured (CN216207186U—a nano-level weak force calibration device).

In the existing gravitational or acceleration modulation methods, the measuring rotary table of the modulation device has a moment of inertia error, and the mass of the weighing measurement calibration will also have a mass error, and the high-frequency jitter drive of the motor will also bring vibration errors, which will bring to the calibration. large error.

Contents of the invention

In order to overcome the deficiencies of the prior art, the present invention proposes a gravitational acceleration modulation device and method, which can be traced back to the law of universal gravitation, which is the most accurate force source known at present, and has no coupling with temperature, vibration and electromagnetic field in theory Effect, high reliability; no need to introduce electromagnetic field, simple operation, small unknown system error.

The technical scheme that the present invention realizes its object of invention is as follows:

A gravitational acceleration modulation device, including particles, a modulation module, a vacuum module, a capture module, and a detection module;

The modulation module includes a flywheel, a rotating shaft, a coupling, a reducer, a motor, a three-axis precision displacement table, and a motor support connected in sequence; the motor drives the periodic relative position of the flywheel through the reducer and the coupling Motion to realize force or acceleration modulation;

The vacuum module is used to provide an ultra-high vacuum environment;

The capture module uses a magnetic field, an optical field or an electric field to capture particles;

The detection module is used to detect motion information of particles;

The modulation module and capture module are integrally installed in the vacuum module.

The vacuum module includes a vacuum chamber, a vacuum tube, a vacuum pump, and a vacuum gauge. The vacuum pump is connected to the bellows, the bellows is connected to the vacuum chamber, and the vacuum gauge is connected to the vacuum chamber. of vacuum.

The detection module sequentially includes a laser, a beam adjustment lens, a reflector, a converging lens, a half-wave plate, a polarization beam splitter, and a detector on the optical path. The particles are irradiated by the laser, and the scattered light of the particles passes through the converging lens, the half-wave plate, and the polarization beam splitter. slice, and finally to the detector to detect the motion information of the particles.

The flywheel is made of stainless steel, gold, silver, and copper metal materials; the flywheel is an axisymmetric structure, including a track-shaped structure and a dumbbell-shaped structure.

The capture module includes a base, a support, and an anti-magnetic levitation structure in order from bottom to top, and is used to levitate particles by forming a magnetic potential well through magnetic levitation.

The particles are made of silicon, silicon dioxide, plexiglass or metal materials.

The modulation module is installed vertically or horizontally.

The motor is a servo motor or a stepping motor.

The three-axis precision displacement stage adopts three-axis fine-tuning of the distance between the flywheel and the particle, and the precision reaches um level.

A gravitational acceleration modulation method, using the gravitational acceleration modulation device to utilize the law of universal gravitation, the steps are as follows:

Step 1: Analyze the force on the particle. The particle is subjected to the gravitational force of the flywheel, and the acceleration generated by the particle is divided into three components, namely: F _x , F _y , F _z ;

Step 2: Transform the coordinate system between the particle and the flywheel, that is, the particle rotates around the flywheel;

Step 3: Integral calculation of the acceleration of the flywheel to the particle;

In the formula, α is the acceleration of the flywheel to the particle, G is the gravitational constant, ρ is the density of the flywheel, the coordinates of the center of mass of the particle are ( x ₀ , y ₀ , z ₀ ), r is the distance between the flywheel and the particle, m is the mass of the particle, M is the mass of the flywheel, the coordinates of the mass center of the flywheel mass unit (x, y, z);

The fourth step is to calculate the X-axis and Y-axis acceleration of the flywheel to the particles;

in,

r ² =( x – x ₀ ) ² + ( y – y ₀ ) ² + ( z – z ₀ ) ²

x ₀ = r _m cos (ωt) , y ₀ = r _m sin (ωt) , z ₀ = d ;

In the formula, a _x is the acceleration of the flywheel to the X-axis direction of the particle, a _y is the acceleration of the flywheel to the Y-axis direction of the particle, G is the gravitational constant, ρ is the density of the flywheel, and the coordinates of the particle center of mass are ( x ₀ , y ₀ , z ₀ ), r is the distance between the flywheel and the particle, r _m is the orbital radius of the particle, and ω is the rotational angular frequency;

The fifth step is to calculate the lateral acceleration perpendicular to the direction of gravity;

The direction of the particle center pointing to the central axis of the cuboid is the x direction, and the direction perpendicular to this direction is the y direction;

Then the gravitational acceleration in the x direction is:

A _x = a _x cos (ωt) + a _y sin (ωt) ;

The gravitational acceleration in the y direction is:

A _y = a _y cos (ωt) – a _x sin (ωt) ;

Finally, the double-frequency modulation of the particle signal is realized, which avoids the influence of the inherent frequency noise of the motor itself, realizes the calibration of gravitational or ng-level acceleration, and avoids the influence of the mass error of the particle and the flywheel.

The beneficial effects of the present invention are:

The present invention can be traced back to the law of universal gravitation, which is the most accurate force source known at present, and has no coupling effect with temperature, vibration, and electromagnetic field in theory, and has high reliability; no need to introduce electromagnetic fields, simple operation, and less error in unknown systems small. The flywheel structure of the present invention is an axisymmetric structure such as a racetrack structure, a dumbbell structure, etc., which ensures the double frequency modulation of the acceleration. The invention realizes the double frequency modulation of the particle signal, avoids the influence of the inherent frequency noise of the motor itself, and realizes the calibration of gravitational force or ng level acceleration. The capture module of the present invention can be captured in a magnetic field, an optical field, or an electric field. The particle material of the present invention is silicon, silicon dioxide, plexiglass, metal and other materials. The modulation module of the present invention can be installed vertically or horizontally. The motor of the present invention is a servo motor, a stepping motor and the like. The three-axis precision displacement table of the present invention can fine-tune the distance between the flywheel and the particle in three axes, and the precision reaches um level. The device and method of the invention can be applied to the technical field of gravity or acceleration modulation calibration.

Description of drawings

Figure 1.1 is a schematic structural diagram of the gravitational acceleration modulation device of the present invention.

Fig. 1.2 is another structural schematic diagram of the gravitational acceleration modulation device of the present invention.

Fig. 2 is a schematic diagram of the force exerted on particles proposed in an embodiment of the present invention.

FIG. 3 is a schematic diagram of a flywheel and particle transformation coordinate system proposed in an embodiment of the present invention.

FIG. 4 is a schematic diagram of the flywheel and particles returning to the original coordinate system proposed in an embodiment of the present invention.

Fig. 5 is a time-domain and frequency-domain diagram of gravitational acceleration in the X direction of a particle proposed in an embodiment of the present invention.

Fig. 6 is a time-domain and frequency-domain diagram of gravitational acceleration in the Y direction of particles proposed in an embodiment of the present invention.

In the figure, particle 1, modulation module 2, vacuum module 3, capture module 4, detection module 5;

The modulation module 2 includes a flywheel 2.1, a rotating shaft 2.2, a coupling 2.3, a reducer 2.4, a motor 2.5, a three-axis precision displacement table 2.6, and a motor support 2.7;

The vacuum module 3 includes a vacuum chamber 3.1, a vacuum tube 3.2, a vacuum pump 3.3, and a vacuum gauge 3.4;

The capture module 4 includes a base 4.1, a bracket 4.2, and an anti-magnetic levitation structure 4.3;

The detection module 5 includes a laser 5.1, a beam adjusting lens 5.2, a mirror 5.3, a converging lens 5.4, a half-wave plate 5.5, a polarization beam splitter 5.6, and a detector 5.7.

detailed description

The present invention will be further described below in conjunction with the accompanying drawings and embodiments. It is easy to understand that, according to the technical solution of the present invention, those skilled in the art can propose multiple structural modes and implementation modes that can be replaced without changing the essence and spirit of the present invention. Therefore, the following specific embodiments and drawings are only exemplary descriptions of the technical solution of the present invention, and should not be regarded as the entirety of the present invention or as a limitation or restriction on the technical solution of the present invention.

As shown in Figure 1.1, a gravitational acceleration modulation device includes a particle 1, a modulation module 2, a vacuum module 3, a capture module 4, and a detection module 5.

As shown in Figure 1.1 and Figure 1.2, the modulation module 2 includes a flywheel 2.1, a rotating shaft 2.2, a coupling 2.3, a reducer 2.4, a motor 2.5, a three-axis precision displacement table 2.6, and a motor support 2.7 connected in sequence; The motor 2.5 drives the flywheel 2.1 to periodically move relative to the position through the reducer 2.4 and the shaft coupling 2.3 to realize force or acceleration modulation.

Described vacuum module 3 comprises vacuum cavity 3.1, vacuum tube 3.2, vacuum pump 3.3, vacuum gauge 3.4, and vacuum pump 3.3 is connected with bellows 3.2, and bellows 3.2 is connected with vacuum cavity 3.1, and vacuum gauge 3.4 is connected with vacuum cavity 3.1, and wherein vacuum pump 3.3 pairs The vacuum chamber 3.1 is vacuumed, the vacuum gauge 3.4 measures the vacuum degree in the vacuum chamber 3.1 in real time, and the vacuum module 3 is mainly used to provide an ultra-high vacuum environment.

The vacuum gauge 3.4 is sealed and fixed on the vacuum chamber 3.1 by screw blades, the vacuum tube 3.2 is connected to the vacuum chamber 3.2 by a screw blade seal, and the vacuum pump 3.3 includes mechanical pumps, molecular pumps, ion pumps, etc., and is connected to the vacuum tube 3.2 by screw nut blades.

The capture module 4 includes a base 4.1, a bracket 4.2, and an anti-magnetic levitation structure 4.3 from bottom to top; the bracket 4.2 is fixed on the base 4.1 by screws, and a beam adjustment lens 5.2, a reflector 5.3, and a converging lens 5.4 are installed on the bracket 4.2 Compared with the anti-magnetic levitation structure 4.3, the particle 1 is suspended by forming a magnetic potential well through magnetic force levitation, and the suspended particle 1 can also be captured in an optical trap or an electric trap.

The detection module 5 sequentially includes a laser 5.1, a beam adjustment lens 5.2, a reflector 5.3, a converging lens 5.4, a half-wave plate 5.5, a polarization beam splitter 5.6, and a detector 5.7 on the optical path. The particle 1 is irradiated by the laser 5.1, and the scattered light of the particle 1 passes through the The converging lens 5.4, the half-wave plate 5.5, the polarization beam splitter 5.6, and finally the detector 5.7 detects the movement information of the particles.

The flywheel 2.1 is an axisymmetric structure, including a track-shaped structure and a dumbbell-shaped structure.

Described flywheel 2.1 adopts metal materials such as stainless steel, gold, silver, copper.

The capture module 4 captures the particles 1 by using a magnetic field, an optical field or an electric field.

The particles 1 are made of silicon, silicon dioxide, plexiglass or metal materials. The particle 1 is irradiated by the laser 5.1, and the scattered light of the particle 1 passes through the converging lens 5.4, the half-wave plate 5.5, the polarization beam splitter 5.6, and finally reaches the detector 5.7 to detect the movement information of the particle 1.

The modulation module 2 is installed vertically or horizontally.

Described motor 2.5 is a servo motor or a stepping motor.

The three-axis precision displacement table 2.6 adopts three-axis fine-tuning of the distance between the flywheel 2.1 and the particle 1, and the precision reaches um level.

The modulation module 2 and the capture module 4 are installed in the vacuum chamber 3 as a whole. First, the base 4.1 is fixed on the bottom plate of the vacuum chamber 3 by screws, and the motor support 2.7 is fixed on the base 4.1 by screws; the three-axis precision displacement table 2.6 passes Screws are fixed on the motor support 2.7, and the three-axis precision translation stage 2.6 is vacuum compatible, and the three-axis directions of the X-axis, Y-axis, and Z-axis are regulated with μm-level precision, and the relative position of the flywheel 2.1 and the particle 1 bracket is precisely controlled , to realize the precise control of the particle 1; the motor 2.5 is fixed to the three-axis precision displacement table 2.6 through the adapter plate 2.7, and the output shaft of the motor 2.5 is connected to the reducer 2.4 to realize the deceleration of the speed of the motor 2.5, ensuring the low-frequency modulation of the flywheel 2.1, deceleration The output shaft of the device 2.4 is connected to the rotating shaft 2.2 through the shaft coupling 2.3, and the rotating shaft 2.2 realizes the consolidation with the flywheel 2.1.

The modulation module 2, vacuum module 3, capture module 4, and detection module 5 of the device are connected and installed, and after confirmation, the anti-magnetic levitation structure 4.3 of the capture module 4 captures the particle 1, and the capture of the particle 1 is completed. Use the vacuum module 3 to turn on the mechanical pump to vacuumize the vacuum chamber 3.1. When the vacuum gauge 3.2 shows that the vacuum chamber is pumped below ^10-1 mbar, turn on the molecular pump to vacuumize the vacuum chamber 3.1. When the vacuum gauge 3.2 shows that the vacuum chamber When the vacuum is lower than 1×10 ^-6 mbar, turning on the ion pump to vacuum can bring the vacuum chamber 3.2 to a higher ultimate vacuum. Start the modulation module 2, adjust the three-axis precision translation stage 2.6, and adjust the three-axis direction of the X-axis, Y-axis, and Z-axis modulation module with μm-level precision, and accurately control the relative position of the flywheel 2.1 and the particle support 4.2, and realize the particle 1 The motor 2.5 moves and drives the flywheel 2.1 to periodically move relative to the position through the reducer 2.4 and the coupling 2.3, so as to realize the gravitational acceleration modulation. The detection module 5 irradiates the particle 1 through the laser 5.1, the light scattered by the particle 1 passes through the converging lens 5.4, the half-wave plate 5.5, the polarization beam splitter 5.6, and finally reaches the detector 5.7 to detect the motion modulation information of the particle 1.

In this embodiment, a gravitational acceleration modulation method utilizes the law of universal gravitation to determine force, and its method includes the following steps:

The first step: as shown in Fig. 2, the force schematic diagram of the particle 1 proposed in an embodiment of the present invention is analyzed. The force analysis of the particle 1 shows that the particle 1 is subjected to the gravitational effect of the flywheel 2.1, and the acceleration produced is divided into 3 components, which are respectively : F _x , F _y , F _z .

The second step: Fig. 3 is a schematic diagram of the coordinate system transformation between the flywheel 2.1 and the particle 1 proposed in an embodiment of the present invention, and transforms the coordinate system between the particle 1 and the flywheel 2.1, that is, the particle 1 rotates around the flywheel 2.1;

Step 3: Integral calculation of the acceleration of the flywheel 2.1 on the particle 1;

In the formula, α is the acceleration of flywheel 2.1 to particle 1, G is the gravitational constant, ρ is the density of flywheel 2.1, the coordinates of the center of mass of particle 1 are ( x ₀ , y ₀ , z ₀ ), r is the distance between flywheel 2.1 and particle 1, m is the mass of the particle 1, M is the mass of the flywheel 2.1, and the coordinates of the center of mass of the mass unit of the flywheel 2.1 (x, y, z).

Step 4: Calculate the X-axis and Y-axis accelerations of the flywheel 2.1 on the particle 1;

where r ² =( x – x ₀ ) ² + ( y – y ₀ ) ² + ( z – z ₀ ) ²

x ₀ = r _m cos (ωt) , y ₀ = r _m sin (ωt) , z ₀ = d ;

In the formula, a _x is the acceleration of the flywheel 2.1 to the X-axis direction of the particle 1, a _y is the acceleration of the flywheel 2.1 to the Y-axis direction of the particle 1, r _m is the orbital radius of the particle 1, and ω is the rotation angular frequency.

Step 5: Figure 4 shows the flywheel 2.1 proposed in an embodiment of the present invention and the particle 1 returning to the original coordinate system, and calculates the lateral acceleration perpendicular to the direction of gravity;

The direction from the center of particle 1 to the central axis of the cuboid is the x direction, and the direction perpendicular to this direction is the y direction.

Then the gravitational acceleration in the x direction is:

A _x = a _x cos(ωt) + a _y sin (ωt) ;

The gravitational acceleration in the y direction is:

A _y = a _y cos(ωt) – a _x sin(ωt) ;

Finally, the double frequency modulation of the particle 1 signal is realized, which avoids the influence of the inherent frequency noise of the motor 2.5 itself, realizes the calibration of gravity or ng-level acceleration, and avoids the influence of the mass error of the particle 1 and the flywheel 2.1.

Fig. 5 and Fig. 6 are the time-domain and frequency-domain diagrams of gravitational acceleration in X and Y directions of particles in the application example.

application example

The flywheel of the modulation module selected in this application implementation case is 20mm in length, 10mm in width, and 10mm in height. The structural shape is a racetrack structure. The material of the flywheel is 304 stainless steel. is 250um, and the radius r _m of the particles relative to the center of the cuboid is 11.2mm.

The operation steps are as follows:

1) Connect and install modulation module 2, vacuum module 3, capture module 4, detection module 5, etc.;

2) After confirming that there is no error, launch Particle 1;

3) The anti-magnetic levitation structure 4.3 of the capture module 4 captures the particle 1 to complete the capture of the particle 1;

4) Use the vacuum module 3 to turn on the mechanical pump to vacuumize the vacuum chamber 3.1;

5) When the vacuum gauge 3.4 shows that the vacuum chamber 3.1 is pumped below 10 ^-1 mbar, turn on the molecular pump to vacuum the vacuum chamber 3.1;

6) When the vacuum gauge 3.4 shows that the vacuum chamber 3.1 is pumped below 1×10 ^-6 mbar, turn on the ion pump to vacuum the vacuum chamber 3.1 to a higher ultimate vacuum;

7) Start the modulation module 2, adjust the three-axis precision displacement table 2.7, and adjust the three-axis direction of the X-axis, Y-axis, and Z-axis modulation module with μm-level precision, and accurately control the relative position of the flywheel 2.1 and the particle 1, so as to realize the fine-tuning of the particle The precision control makes the distance between the flywheel 2.1 and the z-direction surface of the particle 1 be 250um;

8) The motor 2.5 moves and drives the flywheel 2.1 through the reducer 2.4 and the coupling 2.3 to rotate periodically at a frequency of 10 Hz to realize the gravitational acceleration modulation of the particle 1;

9) The detection module 4 irradiates the particle 1 through the laser 5.1, the scattered light of the particle 1 passes through the converging lens 5.4, the half-wave plate 5.5, the polarization beam splitter 5.6, and finally reaches the detector 5.7 to detect the motion modulation information of the particle 1;

10) Finally, through the MATLAB program, the time-domain and frequency-domain diagrams of the gravitational acceleration in the X and Y directions of the particles can be calculated.

The implementations in the above description can be further combined or replaced, and the implementations are only descriptions of preferred embodiments of the present invention, and are not intended to limit the concept and scope of the present invention. Various changes and improvements made by technicians to the technical solution of the present invention belong to the protection scope of the present invention. The scope of protection for the present invention is given by the appended claims and any equivalents thereof.

Claims (10)

1. A gravitational acceleration modulation device, characterized by: comprising particles (1), modulation module (2), vacuum module (3), capture module (4), detection module (5); The modulation module (2) includes a flywheel (2.1), a rotating shaft (2.2), a coupling (2.3), a reducer (2.4), a motor (2.5), and a three-axis precision displacement table (2.6) connected in sequence . The motor support (2.7); wherein the motor (2.5) drives the flywheel (2.1) to move periodically relative to the position through the reducer (2.4) and the coupling (2.3) to realize force or acceleration modulation; The vacuum module (3) is used to provide an ultra-high vacuum environment; The capture module (4) captures the particles (1) by using a magnetic field, an optical field or an electric field; The detection module (5) is used to detect the movement information of the particles (1); The modulation module (2) and the capture module (4) are integrally installed in the vacuum module. 2. The gravitational acceleration modulation device according to claim 1, characterized in that: the vacuum module (3) includes a vacuum chamber (3.1), a bellows (3.2), a vacuum pump (3.3), a vacuum gauge (3.4), a vacuum pump (3.3) is connected with the bellows (3.2), the bellows (3.2) is connected with the vacuum chamber (3.1), the vacuum gauge (3.4) is connected with the vacuum chamber (3.1), and the vacuum pump (3.3) evacuates the vacuum chamber (3.1) , the vacuum gauge (3.4) measures the vacuum degree in the vacuum chamber (3.1) in real time. 3. The gravitational acceleration modulation device according to claim 1, characterized in that: the detection module (5) sequentially includes a laser (5.1), a beam adjustment lens (5.2), a mirror (5.3), and a converging lens on the optical path (5.4), half-wave plate (5.5), polarizing beam splitter (5.6), detector (5.7), the particle (1) is irradiated by the laser (5.1), and the scattered light of the particle (1) passes through the converging lens (5.4), half-wave film (5.5), polarization beam splitter (5.6), and finally to the detector (5.7) to detect the motion information of particles. 4. The gravitational acceleration modulation device according to claim 1, characterized in that: the flywheel (2.1) is made of stainless steel, gold, silver, copper metal materials; the flywheel (2.1) is an axisymmetric structure, including a racetrack structure , Dumbbell-shaped structure. 5. The gravitational acceleration modulation device according to claim 1, characterized in that: the capture module (4) sequentially includes a base (4.1), a bracket (4.2), and an anti-magnetic levitation structure (4.3) from bottom to top, for The particle (1) is suspended by forming a magnetic potential well through magnetic levitation. 6. The gravitational acceleration modulation device according to claim 1, characterized in that: the particles (1) are made of silicon, silicon dioxide, plexiglass or metal materials. 7. The gravitational acceleration modulation device according to claim 1, characterized in that: the modulation module (2) is installed vertically or horizontally. 8. The gravitational acceleration modulation device according to claim 1, characterized in that: the motor (2.5) is a servo motor or a stepping motor. 9. The gravitational acceleration modulation device according to claim 1, characterized in that: the three-axis precision translation stage (2.6) adopts three-axis fine-tuning of the distance between the flywheel (2.1) and the particle (1), and the accuracy reaches um level. 10. A gravitational acceleration modulation method is characterized in that: adopt the gravitational acceleration modulation device according to claim 1 to utilize the law of universal gravitation, and the steps are as follows: Step 1: Analyze the force on the particle (1). The particle (1) is subjected to the gravitational force of the flywheel (2.1), and the acceleration generated by the particle (1) is divided into three components, namely: F _x , F _y , F _z ; The second step: Transform the coordinate system of the particle (1) and the flywheel (2.1), that is, the particle rotates around the flywheel; Step 3: Integral calculation of the acceleration of the flywheel (2.1) on the particle (1);

In the formula, α is the acceleration of the flywheel (2.1) to the particle (1), G is the gravitational constant, ρ is the density of the flywheel, the coordinates of the center of mass of the particle (1) are ( x ₀ , y ₀ , z ₀ ), r is the flywheel (2.1 ) and the particle (1), m is the mass of the particle (1), M is the mass of the flywheel (2.1), and the mass center coordinates (x, y, z) of the mass unit of the flywheel (2.1); The fourth step is to calculate the X-axis and Y-axis acceleration of the particle (1) by the flywheel (2.1);

in, r ² =( x – x ₀ ) ² + ( y – y ₀ ) ² + ( z – z ₀ ) ² x ₀ = r _m cos (ωt) , y ₀ = r _m sin (ωt) , z ₀ = d ; In the formula, a _x is the acceleration of the flywheel (2.1) on the X-axis direction of the particle (1), a _y is the acceleration of the flywheel (2.1) on the Y-axis direction of the particle (1), G is the gravitational constant, and ρ is the flywheel ( 2.1) Density, the coordinates of the center of mass of the particle (1) are ( x ₀ , y ₀ , z ₀ ), r is the distance between the flywheel (2.1) and the particle (1), r _m is the orbital radius of the particle (1), ω is the rotational angular frequency , d is the distance between the particle (1) and the flywheel (2.1) in the Z-axis direction; The fifth step is to calculate the lateral acceleration perpendicular to the direction of gravity; The direction of the center of the particle (1) pointing to the central axis of the cuboid is the x direction, and the direction perpendicular to this direction is the y direction; Then the gravitational acceleration in the x direction is: A _x = a _x cos(ωt) + a _y sin (ωt) ; The gravitational acceleration in the y direction is: A _y = a _y cos(ωt) – a _x sin(ωt) ; Finally, the double frequency modulation of the particle (1) signal is realized, which avoids the influence of the inherent frequency noise of the motor (2.5), realizes the calibration of gravity or ng-level acceleration, and eliminates the mass of the particle (1) and the flywheel (2.1) The impact of errors.

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