Thrust frame traceable calibration device and method based on cylindrical capacitor array

Abstract

The invention relates to the technical field of calibration, and discloses a cylindrical capacitor array-based thrust frame traceable calibration device, which comprises a coaxial cylindrical capacitor array electrostatic force generation module, which comprises a cylindrical capacitor array fixed end polar plate and a cylindrical capacitor array moving end polar plate, the two polar plates are coaxially mounted, and the cylindrical capacitor array electrostatic force generation module is connected with the cylindrical capacitor array fixed end polar plate and the cylindrical capacitor array moving end polar plate; the electrostatic generator is used for generating axial electrostatic force; the capacitance acquisition and measurement module comprises a capacitance bridge and a shielding wire covered by a metal net-shaped braid layer, and is used for measuring a capacitance value and controlling relative movement between polar plates through a nano micropositioner; and the force value calculation and verification module is used for calculating an electrostatic force value according to the capacitance gradient and the applied voltage and verifying the force value through an electronic balance. The coaxial cylindrical capacitor is directly installed on the thrust frame, an accurate electrostatic force value can be directly obtained by measuring the capacitance and calculating the capacitance gradient, attitude errors caused by inconsistency of a previous calibration device based on electromagnetic force and electrostatic force during balance weighing and thrust frame calibration are eliminated, and the calibration precision is improved.

Description

Technical Field

[0001] The invention relates to the field of calibration technology, and in particular to a traceable calibration device and method for a thrust frame based on a cylindrical capacitor array. Background Art

[0002] Microthrusters are often used to compensate for non-conservative forces such as solar pressure and cosmic rays on satellites in space environments. Their performance indicators directly affect the attitude control accuracy of satellites. Therefore, a variety of thrust frame structures have been developed at home and abroad to evaluate the performance of microthrusters. However, regardless of the specific structure of the thrust frame, before thrust measurement, the thrust frame must be calibrated using a standard weak force to determine the relationship between the displacement response of the thrust frame and the constant force.

[0003] At present, commonly used thrust frame calibration technologies include gravity method, electromagnetic force method, electrostatic force method, etc., which are usually divided into contact and non-contact types. The gravity method belongs to contact calibration. Although the principle is simple and easy to implement, it is difficult to accurately generate tiny forces below the micronewton level due to the unpredictable friction error of the pulley system. In contrast, the electromagnetic force method and the electrostatic force method are both non-contact calibration methods. Electromagnetic force is generated between the magnet and the coil or the coil and the coil after power is turned on, and electrostatic force is generated between the plates under high voltage conditions. Both have the advantages of high precision and easy adjustment.

[0004] However, before applying electromagnetic force or electrostatic force to calibrate the thrust frame, it is usually necessary to perform self-calibration with the help of an electronic balance to establish an accurate conversion relationship between current-electromagnetic force or voltage-electrostatic force. After the calibration device is reinstalled, its posture on the thrust frame is often different from that during the balance calibration, resulting in unavoidable measurement errors. In addition, the thrust frame is usually installed in the atmosphere and used in a vacuum. During the operation of the vacuum system, as the gas is quickly pumped out, the flow of gas in the vacuum chamber may cause the relative posture of the calibration device to change, further exacerbating the calibration error.

[0005] Researchers have conducted extensive research on the attitude error of the calibration device. Researchers from the University of the Chinese Academy of Sciences developed a ring-shaped electrostatic comb and found that when the relative position of the electrostatic comb fins is offset by 0.1-0.4mm, the maximum deviation of the electrostatic force can reach 9.083%. Researchers from the China University of Aerospace Engineering developed a voice coil motor electromagnetic device and pointed out that when the relative position deviation exceeds 2.5mm, the measurement error will exceed 5%. These studies show that the relative position offset introduced by the attitude error is a key factor limiting the calibration accuracy of the thrust frame.

[0006] In addition, existing calibration devices often find it difficult to simultaneously cover a large range from sub-micronewtons to tens of millinewtons, and range expansion is difficult, which is not conducive to calibrating thrust racks with different calibration force requirements under the same environment.

[0007] Therefore, there is an urgent need to develop new thrust frame calibration devices and methods. Summary of the invention

[0008] In view of the shortcomings of the prior art, the present invention provides a traceable calibration device and method for a thrust frame based on a cylindrical capacitor array, which solves the problem that calibration devices often find it difficult to simultaneously cover a large range from sub-micronewtons to tens of millinewtons and that range expansion is difficult.

[0009] To achieve the above objectives, the present invention is implemented through the following technical solutions: a thrust frame traceable calibration device and method based on a cylindrical capacitor array, comprising:

[0010] A coaxial cylindrical capacitor array electrostatic force generating module, the module comprising a cylindrical capacitor array fixed end plate and a cylindrical capacitor array moving end plate, the two plates are coaxially mounted to generate an electrostatic force along the axial direction;

[0011] A capacitance acquisition and measurement module, which includes a capacitance bridge and a shielded wire covered with a metal mesh braided layer, and is used to measure the capacitance value and control the relative movement between the plates through a nano-micromotion stage;

[0012] A force value calculation and verification module, which is used to calculate the electrostatic force value according to the capacitance gradient and the applied voltage, and verify the force value through an electronic balance;

[0013] An optical plate and a thrust frame, wherein a capacitor bridge and a high-voltage power supply are arranged on one side of the upper surface of the optical plate, the positive output end of the high-voltage power supply is connected to the metal joint of the moving end plate of the cylindrical capacitor array, and the negative output end of the high-voltage power supply is connected to the metal joint of the fixed end plate of the cylindrical capacitor array.

[0014] Preferably, the cylindrical capacitor array in the electrostatic force generating module is composed of a plurality of cylindrical capacitors connected in parallel, each cylindrical capacitor is processed by mechanical integration, and the edge effect is reduced by shortening the length of the electrode plate.

[0015] Preferably, the capacitance bridge of the capacitance acquisition and measurement module is used to acquire the capacitance value change of the cylindrical capacitor array, and calculate the electrostatic force through the capacitance gradient:

[0016]

[0017] In the formula, is the capacitance gradient, which is the rate of change of capacitance in the direction perpendicular to the plate. When the relative position of the plates changes very little, it can be approximately considered a constant. When the potential difference between the plates remains unchanged, increasing the capacitance gradient can significantly increase the magnitude of the electrostatic force.

[0018] Preferably, the force value calculation and verification module calculates the electrostatic force by comparing the capacitance gradient with the electrostatic force measured by a balance.

[0019] Preferably, the electrostatic force acts along the axial direction of the thrust frame, and the displacement change of the thrust frame is monitored by a laser displacement sensor and a displacement target.

[0020] A method for traceable calibration of a thrust frame based on a cylindrical capacitor array comprises the following steps:

[0021] Step 1: Install the fixed end plate of the cylindrical capacitor array on the thrust frame, and install the moving end plate coaxially with it;

[0022] Step 2: Control the moving end plate to move toward the fixed end plate with a fixed step length by using the nano-micromotion stage, and record the change of the capacitance value;

[0023] Step 3: Calculate the capacitance gradient based on the change in capacitance value, and calculate the generated electrostatic force in combination with the applied voltage;

[0024] Step 4: Apply electrostatic force to the thrust frame and calculate the thrust stiffness using the displacement of the thrust frame and Hooke's law

[0025] Preferably, the capacitance gradient is calculated by measuring the relative motion step length and capacitance change between the plates, and the capacitance gradient between the plates can be expressed as:

[0026]

[0027] Wherein, N is the number of cylindrical capacitors in the fixed end plate 3 of the container array and the moving end plate 4 of the cylindrical capacitor array. The capacitance value of a single capacitor can be adjusted by designing the structural parameters of the inner and outer poles of the capacitor.

[0028] Preferably, the electrostatic force is verified by an electronic balance, which specifically includes the following steps:

[0029] The fixed end electrode plate of the cylindrical container array is placed at the center of the electronic balance tray, and the moving end electrode plate of the cylindrical container array is inserted into the center of the electronic balance tray to a certain depth through a multi-degree-of-freedom adjustment device;

[0030] A high voltage power supply is used to generate a potential difference between the fixed end plate of the cylindrical container array and the moving end plate of the cylindrical container array;

[0031] The magnitude of the electrostatic force generated by the capacitor array is:

[0032] F E =(m1-m2)g

[0033] In the formula, m1 is the reading of the balance when the high voltage is not working, m2 is the reading of the balance when the high voltage is working, and g is the local acceleration of gravity.

[0034] Preferably, the stiffness of the thrust frame (10) is calculated by the change of electrostatic force and displacement:

[0035]

[0036] For a coaxial cylindrical capacitor array, the capacitance gradient can be further expressed as: Where ε is the dielectric constant between the plates, N is the number of cylindrical thin tubes, R1 is the inner radius of a single cylindrical thin tube in the moving end plate 4 of the cylindrical capacitor array, and R2 is the outer radius of a single cylindrical thin tube in the fixed end plate 3 of the cylindrical capacitor array.

[0037] Preferably, the plates of the capacitor array are connected to a high voltage power supply via a shielding wire covered by a metal mesh braided layer to shield stray capacitance.

[0038] The invention provides a thrust frame traceable calibration device and method based on a cylindrical capacitor array.

[0039] It has the following beneficial effects:

[0040] 1. The present invention designs a coaxial cylindrical capacitor array so that the same calibration device has a large range of calibration forces.

[0041] 2. The present invention directly installs the coaxial cylindrical capacitor on the thrust frame. By measuring the capacitance and calculating the capacitance gradient, the accurate electrostatic force value can be directly obtained, eliminating the posture error introduced by the inconsistency between the previous calibration device based on electromagnetic force and electrostatic force during balance weighing and thrust frame calibration, thereby improving the calibration accuracy.

[0042] 3. The present invention characterizes the electrostatic force used to calibrate the thrust frame as three physical quantities, namely capacitance, length and voltage, which can be directly traced back to the International System of Units, thereby achieving traceable calibration of the thrust frame and ensuring the reliability of the thrust frame measurement results.

[0043] The invention has the advantages of large measuring range, high precision, non-contact and traceability to the international system of units. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] Figure 1 It is a three-dimensional schematic diagram of the calibration device of the present invention;

[0045] Figure 2 It is the front view of the calibration device of the present invention;

[0046] Figure 3 It is a right side view of the present invention;

[0047] Figure 4 A top view of the present invention;

[0048] Figure 5 A schematic diagram of a coaxial cylindrical capacitor array of the present invention;

[0049] Figure 6 is a cross-sectional view of a single cylindrical capacitor in the coaxial cylindrical capacitor array of the present invention;

[0050] Figure 7 A schematic diagram of the capacitance gradient of the calibration device of the present invention;

[0051] Figure 8 It is a schematic diagram of the calibration force range of the calibration device of the present invention;

[0052] Fig. 9 It is a schematic diagram of the traceable calibration process of the present invention.

[0053] Among them, 1. Laser displacement sensor; 2. Displacement target; 3. Fixed end plate of cylindrical capacitor array; 4. Moving end plate of cylindrical capacitor array; 5. Nano-micromotion stage; 6. Shielding wire covered with metal mesh braided layer; 7. Capacitor bridge; 8. High voltage power supply; 9. Optical plate; 10. Thrust frame. DETAILED DESCRIPTION

[0054] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0055] Please refer to the attached Figure 1 -Attached Figure 8 The embodiment of the present invention provides a thrust frame traceable calibration device based on a cylindrical capacitor array, comprising:

[0056] The fixed end plate 3 of the cylindrical capacitor array is fixed to one side of the top of the thrust frame 10 by a customized tooling, and the moving end plate 4 of the cylindrical capacitor array is also fixed to the nano-micro-motion platform 5 by a customized tooling. The fixed end plate 3 of the cylindrical capacitor array and the moving end plate 4 of the cylindrical capacitor array are coaxially installed and have a certain overlapping depth in the axial direction.

[0057] Ground the thrust frame 10, and then connect the two capacitance measurement interfaces of the capacitance bridge 7 to the metal joints of the fixed end plate 3 and the moving end plate 4 of the cylindrical capacitor array through two shielding wires 6 covered with metal mesh woven layers, and perform subsequent operations after the reading of the capacitance bridge 7 is stable.

[0058] One electrode plate in the cylindrical capacitor array is mounted on the thrust frame 10, and the other electrode plate is mounted coaxially therewith, inserted to a certain depth, and fixed on the six-degree-of-freedom adjustable device; then the positive output end of the high-voltage power supply 8 is connected to the electrode plate on the nano-micro-motion stage 5, and the negative output end is connected to the capacitor electrode plate on the thrust frame 10, and the thrust frame 10 is connected to the ground with wires to achieve the effect of shielding stray capacitance;

[0059] The nano-fine motion stage 5 is controlled to move in a single direction with a fixed step length, and repeated several times; the two ends of the capacitance bridge are respectively connected to the two plates of the cylindrical capacitor array, and the changes in the capacitance readings of the capacitance bridge 7 when the nano-fine motion stage 5 moves are recorded in sequence; the capacitance gradient is calculated according to the step length of the nano-fine motion stage 5 and the changes in the readings of the capacitance bridge 7, and the expression of the capacitance gradient is: Where c is the capacitance value between the cylindrical capacitor arrays, and z is the step length of the movement of the moving end plate 4 of the cylindrical capacitor array;

[0060] The positive output end of the high-voltage power supply 8 is connected to the metal connector of the moving end plate 4 of the cylindrical capacitor array, and the negative output end of the high-voltage power supply 8 is connected to the metal connector of the fixed end plate 3 of the cylindrical capacitor array, so that after the high-voltage power supply 8 outputs voltage, the fixed end plate 3 of the cylindrical capacitor array and the moving end plate 4 of the cylindrical capacitor array can generate an equivalent potential difference.

[0061] The coaxial cylindrical capacitor array electrostatic force generating module includes a high voltage power supply 8 and two capacitor plates, each of which is a rectangular parallelepiped configuration, and from bottom to top are a mounting base plate, an insulating layer, and a cylindrical thin layer, wherein the cylindrical wall layer is obtained by cutting a coaxial small diameter cylinder from a large diameter cylinder, and the material used is aluminum alloy 7075-T6;

[0062] For a coaxial cylindrical capacitor array, the capacitance gradient can be further expressed as: Where ε is the dielectric constant between the plates, N is the number of cylindrical thin tubes, R1 is the inner radius of a single cylindrical thin tube in the moving end plate 4 of the cylindrical capacitor array, and R2 is the outer radius of a single cylindrical thin tube in the fixed end plate 3 of the cylindrical capacitor array.

[0063] The nano-fine motion stage 5 is controlled to drive the cylindrical capacitor array moving end plate 4 to move toward the cylindrical capacitor array fixed end plate 3 with a specific step length, and after the reading of the capacitance bridge 7 is stable, the capacitance value after the movement of the nano-fine motion stage is recorded in sequence.

[0064] The capacitance acquisition and measurement module mainly includes a capacitance bridge 7, a shielded wire 6 covered by a metal mesh braided layer, and a nano-micromotion stage 5. The two ports of the capacitance bridge 7 are both connected to the two plates of the coaxial cylindrical capacitor using shielded wires. When the nano-micromotion stage 5 drives the capacitor plates to move and changes the capacitance value between the capacitors, the capacitance bridge 7 is used to record the capacitance changes in sequence and upload them to the host computer.

[0065] According to Hooke's law, the stiffness of the thrust frame 10 can be calculated through the electrostatic force and the position change of the displacement target 2 .

[0066] The rigidity of the thrust frame 10 is: Δx is the displacement change of target 2.

[0067] The force value calculation and verification module mainly includes a precision electronic balance. The capacitance gradient of the cylindrical capacitor array is calculated based on the capacitance value recorded by the capacitance bridge 7 and the movement step length of the nano-micro-motion stage 5, and the electrostatic force is calculated in combination with the voltage value of the high-voltage power supply 8. The expression of the electrostatic force is: Where η is the capacitance gradient and U is the potential difference between the cylindrical capacitor arrays. Under the same voltage, by increasing the number of thin cylindrical tubes in the cylindrical capacitor array, the capacitance gradient can be increased and the range of electrostatic force can be expanded.

[0068] The electrostatic force device is placed on a precision electronic balance, the capacitance gradient is adjusted to be consistent with the previous one, and the electrostatic force value is calculated again by the balance reading and the local gravity acceleration. The electrostatic force values ​​obtained by the two methods are compared to verify the correctness of the invented method.

[0069] The specific value of the electrostatic force applied at this time is calculated according to the voltage value applied by the high voltage power supply 8 and the calculated capacitance gradient;

[0070] In order to ensure the correctness of the calculation results, one electrode plate in the cylindrical capacitor array is placed in the center of the balance tray, and the other is installed coaxially with it. The above steps are repeated, and the electrostatic force value obtained by calculating the capacitance gradient is compared with the electrostatic force value obtained by multiplying the balance reading and the local gravitational acceleration to determine the accuracy of the electrostatic force value. The force value is applied to the thrust frame 10 as a calibration force of a certain size. The stiffness of the thrust frame 10 can be calculated by combining the displacement of the thrust frame 10 deformation with Hooke's law, thereby completing the calibration process of the thrust frame.

[0071] Please see attached Fig. 9 , the main working process of this device is as follows:

[0072] 1. When voltage is applied to two capacitor plates, an electrostatic attraction will be generated. When the positive and negative terminals of the high-voltage power supply are connected to the two capacitor plates respectively and the potential difference between the plates is U, an electrostatic force F perpendicular to the plates will be generated.E :

[0073]

[0074] In the formula, is the capacitance gradient, which is the rate of change of capacitance in the direction perpendicular to the plate. When the relative position of the plates changes very little, it can be approximately considered a constant. When the potential difference between the plates remains unchanged, increasing the capacitance gradient can significantly increase the magnitude of the electrostatic force.

[0075] 2. If Figure 5 As shown in the figure, when the outer and inner electrodes of the capacitor are installed coaxially, the capacitance between the inner and outer electrodes is:

[0076]

[0077] Where ε is the dielectric constant between the plates, l is the length of the capacitor electrode, R1 is the inner radius of the outer pole of the capacitor, and R2 is the outer radius of the inner pole of the capacitor.

[0078] 3. If Figure 5 As shown, when the nano-micro-motion stage drives the moving end plate 4 of the cylindrical capacitor array to perform a small movement along the axial direction of the fixed end plate 3 of the cylindrical capacitor array, since the cylindrical capacitors on the plates are connected in parallel, the capacitance gradient between the plates can be expressed as:

[0079]

[0080] Wherein, N is the number of cylindrical capacitors in the fixed end plate 3 of the container array and the moving end plate 4 of the cylindrical capacitor array. The capacitance value of a single capacitor can be adjusted by designing the structural parameters of the inner and outer poles of the capacitor.

[0081] 4. When the high voltage power supply 5 is connected to the fixed end plate 3 of the cylindrical container array and the moving end plate 4 of the cylindrical capacitor array through the shielding wire 6 covered by the metal mesh braided layer and provides working voltage, an electrostatic force is generated along the axial direction of the plate.

[0082]

[0083] 5. The electrostatic force is along the axial direction of the electrode plate, that is, along the most sensitive deformation direction of the thrust frame 10. The position of the displacement target 2 is monitored by the laser displacement sensor 1 to obtain the maximum deformation Δx of the thrust frame 10 before and after the electrostatic force acts on the top of the thrust frame 10, and then the stiffness of the thrust frame 10 can be calculated as:

[0084]

[0085] For a coaxial cylindrical capacitor array, the capacitance gradient can be further expressed as: Where ε is the dielectric constant between the plates, N is the number of cylindrical thin tubes, R1 is the inner radius of a single cylindrical thin tube in the moving end plate 4 of the cylindrical capacitor array, and R2 is the outer radius of a single cylindrical thin tube in the fixed end plate 3 of the cylindrical capacitor array.

[0086] 6. The magnitude of the electrostatic force generated in step 4 can be verified by using an electronic balance weighing method. The steps are: place the fixed end plate 3 of the cylindrical container array at the center of the electronic balance tray, and insert the moving end plate 4 of the cylindrical container array coaxially with it and to a certain depth through a multi-degree-of-freedom adjustment device. Use a high-voltage power supply 5 to generate a potential difference between the fixed end plate 3 of the cylindrical container array and the moving end plate 4 of the cylindrical container array. At this time, the magnitude of the electrostatic force generated by the capacitor array is:

[0087] F E =(m1-m2)g

[0088] In the formula, m1 is the reading of the balance when the high voltage is not working, m2 is the reading of the balance when the high voltage is working, and g is the local acceleration of gravity.

[0089] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A thrust frame traceable calibration device based on a cylindrical capacitor array, characterized in that: include: A coaxial cylindrical capacitor array electrostatic force generating module, the module comprising a cylindrical capacitor array fixed end plate (3) and a cylindrical capacitor array moving end plate (4), the two plates being coaxially mounted and used to generate electrostatic force along the axial direction; A capacitance acquisition and measurement module, the module comprising a capacitance bridge (7) and a shielded wire (6) covered with a metal mesh braided layer, and used for measuring capacitance values ​​and controlling the relative movement between the electrodes through a nano-micromotion stage (5); A force value calculation and verification module, which is used to calculate the electrostatic force value according to the capacitance gradient and the applied voltage, and verify the force value through an electronic balance; An optical plate and a thrust frame, wherein a capacitor bridge and a high-voltage power supply are arranged on one side of the upper surface of the optical plate, the positive output end of the high-voltage power supply is connected to the metal joint of the moving end plate of the cylindrical capacitor array, and the negative output end of the high-voltage power supply is connected to the metal joint of the fixed end plate of the cylindrical capacitor array.

2. A thrust frame traceable calibration device based on a cylindrical capacitor array according to claim 1, characterized in that: The cylindrical capacitor array in the electrostatic force generating module is composed of a plurality of cylindrical capacitors connected in parallel, each cylindrical capacitor is processed by mechanical integration, and the edge effect is reduced by shortening the length of the electrode plate.

3. The thrust frame traceable calibration device based on cylindrical capacitor array according to claim 1 is characterized in that: The capacitance bridge (7) of the capacitance acquisition and measurement module is used to acquire the capacitance value change of the cylindrical capacitor array and calculate the electrostatic force through the capacitance gradient: In the formula, is the capacitance gradient, which is the rate of change of capacitance in the direction perpendicular to the plate. When the relative position of the plates changes very little, it can be approximately considered a constant. When the potential difference between the plates remains unchanged, increasing the capacitance gradient can significantly increase the magnitude of the electrostatic force.

4. The thrust frame traceable calibration device based on a cylindrical capacitor array according to claim 1, characterized in that: The force value calculation and verification module calculates the electrostatic force by comparing the capacitance gradient with the electrostatic force weighed by the balance.

5. The thrust frame traceable calibration device based on cylindrical capacitor array according to claim 1, characterized in that: The electrostatic force acts along the axial direction of the thrust frame (10), and the displacement change of the thrust frame (10) is monitored through the laser displacement sensor (1) and the displacement target (2).

6. A method for traceable calibration of a thrust frame based on a cylindrical capacitor array, characterized in that: A thrust frame traceable calibration device based on a cylindrical capacitor array according to any one of claims 1 to 5, comprising the following steps: Step 1: Install the fixed end plate (3) of the cylindrical capacitor array on the thrust frame (10), and install the moving end plate (4) coaxially therewith; Step 2: Control the moving end plate (4) to move toward the fixed end plate (3) with a fixed step length by using the nano-micro-motion stage (5), and record the change of the capacitance value; Step 3: Calculate the capacitance gradient based on the change in capacitance value, and calculate the generated electrostatic force in combination with the applied voltage; Step 4: applying electrostatic force to the thrust frame (10), and calculating the stiffness of the thrust frame (10) using the displacement of the thrust frame (10) and Hooke's law.

7. The method for traceable calibration of a thrust frame based on a cylindrical capacitor array according to claim 6, characterized in that: The capacitance gradient is calculated by measuring the relative motion step length and capacitance change between the plates. The capacitance gradient between the plates can be expressed as: Wherein, N is the number of cylindrical capacitors in the fixed end plate 3 of the container array and the moving end plate 4 of the cylindrical capacitor array. The capacitance value of a single capacitor can be adjusted by designing the structural parameters of the inner and outer poles of the capacitor.

8. The method for traceable calibration of a thrust frame based on a cylindrical capacitor array according to claim 6, characterized in that: The electrostatic force is verified by an electronic balance, which specifically includes the following steps: The fixed end electrode plate of the cylindrical container array is placed at the center of the electronic balance tray, and the moving end electrode plate of the cylindrical container array is inserted into the center of the electronic balance tray to a certain depth through a multi-degree-of-freedom adjustment device; A high voltage power supply is used to generate a potential difference between the fixed end plate of the cylindrical container array and the moving end plate of the cylindrical container array; The magnitude of the electrostatic force generated by the capacitor array is: F E =(m1-m2)g In the formula, m1 is the reading of the balance when the high voltage is not working, m2 is the reading of the balance when the high voltage is working, and g is the local acceleration of gravity.

9. The method for traceable calibration of a thrust frame based on a cylindrical capacitor array according to claim 6, characterized in that: The stiffness of the thrust frame (10) is calculated by the change of electrostatic force and displacement: For a coaxial cylindrical capacitor array, the capacitance gradient can be further expressed as: Where ε is the dielectric constant between the plates, N is the number of cylindrical thin tubes, R1 is the inner radius of a single cylindrical thin tube in the moving end plate 4 of the cylindrical capacitor array, and R2 is the outer radius of a single cylindrical thin tube in the fixed end plate 3 of the cylindrical capacitor array.

10. The method for traceable calibration of a thrust frame based on a cylindrical capacitor array according to claim 6, characterized in that: The plates of the capacitor array are connected to a high-voltage power supply (8) via a shielding wire (6) covered with a metal mesh braided layer, so as to shield stray capacitance.

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