Acceleration sensor calibration device and method suitable for hypergravity centrifugal environment

Abstract

This invention discloses an accelerometer calibration device and method suitable for centrifugal conditions under hypergravity. A vertical positioning bracket is fixedly connected to a horizontal slider at the end of the dual-axis linear module of the calibration device. The accelerometer to be calibrated is fixedly connected to the vertical positioning bracket. Two X-axis displacement sensor brackets and two Y-axis displacement sensor brackets are located on the outer periphery of the dual-axis linear module. Corresponding X-axis laser displacement sensors and Y-axis laser displacement sensors are respectively installed on the two X-axis and two Y-axis displacement sensor brackets. The X-axis laser displacement sensors, Y-axis laser displacement sensors, the accelerometer to be calibrated, and the dual-axis linear module are all electrically connected to a calibration controller. This invention has a simple structure, is industrially controllable, and achieves accurate calibration of accelerometers under hypergravity conditions.

Description

Technical Field

[0001] This invention relates to the field of accelerometer calibration technology, specifically to an accelerometer calibration device and calibration method suitable for centrifugal environments under hypergravity. Background Technology

[0002] In a centrifugal environment with heightened gravity, the volume forces increase significantly, leading to a rise in the static load on the internal mechanical structures of the accelerometer (such as preload springs, mass supports, adhesive interfaces, or clamping interfaces). This results in non-negligible changes in preload, contact stiffness, and internal stress distribution. These changes directly affect key performance parameters of the sensor, including sensitivity, zero-point offset, and linearity. Therefore, sensor sensitivity calibrated under normal gravity conditions cannot be directly applied to conditions with heightened gravity.

[0003] In normal gravity environments, traditional calibration methods typically use known standard accelerometers to compare and calibrate the accelerometer under test. This method relies on standard references traceable to the International System of Units (SI). However, in hypergravity environments, this method faces a fundamental limitation: there is currently a lack of traceable acceleration reference standards for hypergravity environments, meaning there are no fully verified hypergravity standard sensors with known or negligible preload effects as a transfer standard. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide an accelerometer calibration device and calibration method suitable for centrifugal environment under hypergravity. The device has a simple structure and is controllable in industrial operation. It does not rely on known standard accelerometers and can calibrate accelerometers under different hypergravity G values. It establishes a quantifiable, reproducible and traceable linear mapping relationship between high-precision acceleration and the output electrical signal of the accelerometer to SI, thereby achieving accurate calibration of the accelerometer under hypergravity conditions.

[0005] The technical solution of this invention is as follows: An accelerometer calibration device suitable for centrifugal environments under extreme gravity includes a worktable, a dual-axis linear module, two X-axis displacement sensor brackets, two Y-axis displacement sensor brackets, two sets of X-axis laser displacement sensors, two sets of Y-axis laser displacement sensors, and a calibration controller. The dual-axis linear module is fixedly connected to the center of the worktable. The dual-axis linear module is composed of an X-axis linear module and a Y-axis linear module spliced ​​together. The drive motor of the X-axis linear module is equipped with an X-axis encoder, and the drive motor of the Y-axis linear module is equipped with a Y-axis encoder. A vertical positioning bracket is fixedly connected to the horizontal slider at the end of the dual-axis linear module. The acceleration sensor to be calibrated is fixedly connected to the vertical positioning bracket. The sensitive axis of the acceleration sensor to be calibrated is parallel to the X-axis or Y-axis of the dual-axis linear module. Two X-axis displacement sensor brackets and two Y-axis displacement sensor brackets are fixedly connected to the worktable and located on the outer periphery of the dual-axis linear module. The two X-axis displacement sensor brackets are symmetrical along the Y-axis of the dual-axis linear module, and the two Y-axis displacement sensor brackets are symmetrical along the X-axis of the dual-axis linear module. Two sets of X-axis laser displacement sensors are respectively installed on the two X-axis displacement sensor brackets and are horizontally oriented towards the vertical positioning brackets. Two sets of Y-axis laser displacement sensors are respectively installed on the two Y-axis displacement sensor brackets and are horizontally oriented towards the vertical positioning brackets. The two sets of X-axis laser displacement sensors, the two sets of Y-axis laser displacement sensors, and the acceleration sensor to be calibrated are all electrically connected to the calibration controller; the two drive motors of the dual-axis linear module and their X-axis encoders and Y-axis encoders are all electrically connected to the frequency converter of the dual-axis linear module, and the frequency converter is electrically connected to the calibration controller.

[0006] The vertical positioning bracket is a cross-shaped vertical plate, with the X-axis and Y-axis vertical plates of the cross-shaped vertical plate being parallel to the X-axis and Y-axis of the dual-axis linear module, respectively. There are two sets of accelerometers to be calibrated, both sets being of the same model. These two sets of accelerometers are respectively mounted on the vertical surfaces of the X-axis and Y-axis vertical plates. The sensitive axis of the accelerometer mounted on the X-axis vertical plate is parallel to the X-axis vertical plate, and the sensitive axis of the accelerometer mounted on the Y-axis vertical plate is parallel to the Y-axis vertical plate.

[0007] A square reinforcing top plate is fixedly connected to the top of the vertical cross plate.

[0008] Both the X-axis displacement sensor bracket and the Y-axis displacement sensor bracket include a vertical plate, a reinforcing rib, and a horizontal mounting plate. The horizontal mounting plate passes horizontally through the vertical plate. A set of X-axis laser displacement sensors or a set of Y-axis laser displacement sensors are mounted on the top surface of the horizontal mounting plate located inside the vertical plate. The reinforcing rib is vertically fixed to the outer surface of the vertical plate, and the top of the reinforcing rib is fixedly connected to the horizontal mounting plate on the outer side of the vertical plate.

[0009] Each of the two sets of X-axis laser displacement sensors and the two sets of Y-axis laser displacement sensors includes multiple laser displacement sensors mounted on corresponding horizontal mounting plates at the same horizontal height.

[0010] A calibration method for accelerometers applicable to centrifugal environments with centrifugation under extreme gravity includes the following steps: (1) Place the part of the accelerometer calibration device, except for the calibration controller and the dual-axis linear module frequency converter, in the basket of the centrifuge. Place the calibration controller and the frequency converter outside the centrifuge. Start the centrifuge and set the acceleration G value. (2) After the centrifuge starts normally, the calibration controller controls the drive motor of the X-axis linear module to reciprocate at the set speed. The displacement signal fed back to the calibration controller by the X-axis encoder is: The displacement signals fed back to the calibration controller by the two sets of X-axis laser displacement sensors are: The two are weighted and fused to obtain high-precision real-time X-axis displacement. , see the following formula (1) for details: (1); In equation (1), The X-axis weighting coefficient, with a value of 0 to 1, is calculated based on the inverse ratio of the mean square error of the two types of sensors by simultaneously collecting time-series data from the X-axis encoder and the X-axis laser displacement sensor under a hypergravity environment with a set hypergravity acceleration G. Similarly, after the centrifuge starts normally, the calibration controller controls the drive motor of the Y-axis linear module to reciprocate at the set speed, and calculates the high-precision real-time displacement of the Y-axis using the following formula (2). : (2); In equation (2), The Y-axis weighting coefficient, with a value of 0 to 1, is calculated based on the inverse ratio of the mean square error of the two types of sensors by simultaneously collecting time-series data from the Y-axis encoder and the Y-axis laser displacement sensor under a hypergravity environment with a set hypergravity acceleration G. This represents the displacement signal fed back from the Y-axis encoder to the calibration controller; This represents the displacement signals fed back to the calibration controller from two sets of Y-axis laser displacement sensors; (3) The high-precision X-axis real-time acceleration is calculated by formula (3) to calibrate the controller. and high-precision Y-axis real-time acceleration ; (3); In equation (3), It represents time and is a continuous time-series variable; (4) The calibration controller constructs a linear relationship between the electrical signal output by the accelerometer to be calibrated and the real-time acceleration, as shown in the following formula (4): (4); In equation (4), The electrical signal output by the accelerometer sensor to be calibrated when the X-axis linear module performs reciprocating motion; The electrical signal output by the accelerometer sensor to be calibrated when the Y-axis linear module performs reciprocating motion; and These represent the sensitivity of the accelerometer to be calibrated mounted on the X-axis vertical plate and the sensitivity of the accelerometer to be calibrated mounted on the Y-axis vertical plate, respectively. and These represent the zero-point drift of the accelerometer to be calibrated mounted on the X-axis vertical plate and the zero-point drift of the accelerometer to be calibrated mounted on the Y-axis vertical plate, respectively. and These represent the noise levels of the accelerometer to be calibrated mounted on the X-axis vertical plate and the accelerometer to be calibrated mounted on the Y-axis vertical plate, respectively. The calibration controller obtains different accelerations by continuously changing the speeds of the drive motors of the X-axis and Y-axis linear modules. or The corresponding electrical signal or Multiple sets of data were fitted and solved to obtain the set hypergravity acceleration G value. and ; (5) After adjusting the hypergravity acceleration G value of the hypergravity centrifuge, the calibration controller repeats steps (2)-(4) to calibrate the linear relationship between the electrical signal output by the acceleration sensor to be calibrated and the real-time acceleration under different hypergravity acceleration G values.

[0011] The and Under a hypergravity environment with a set hypergravity acceleration G value, the dual-axis linear module is kept stationary while continuously acquiring electrical signals from the accelerometers to be calibrated mounted on the X-axis vertical plate and the accelerometer to be calibrated mounted on the Y-axis vertical plate within a set time period, thus obtaining... , Then, the electrical signal sequences acquired along the X and Y axes are subjected to moving average filtering to remove noise. and Finally, the arithmetic mean of the filtered X-axis and Y-axis electrical signal sequences is taken to obtain the zero-point drift under the set hypergravity acceleration G value. and After adjusting the acceleration G value of the centrifuge, repeat the above steps to re-acquire and determine the zero-point drift corresponding to the acceleration G value. and .

[0012] Both drive motors of the dual-axis linear module are driven by a frequency converter that outputs a compensation torque to achieve drive control. The specific calculation formula is shown in the following formula (5): (5); In equation (5), Representing the load torque, the frequency converter collects the three-phase current of the drive motor stator in real time and estimates the load torque under the current hypergravity acceleration G value based on the vector control model; This represents the gravitational torque generated by the rotor under hypergravity conditions; Represents the rotor mass of the drive motor; This represents the G-value, which indicates the acceleration due to gravity set in the centrifuge. This represents the rotor eccentricity of the drive motor.

[0013] Advantages of this invention: (1) The accelerometer calibration device of the present invention has a simple structure and controllable operating conditions. It can calibrate the accelerometer under different hypergravity G values ​​without the need for a known standard accelerometer, and has a wide range of applications.

[0014] (2) The present invention is equipped with a dual-axis linear module for displacement acquisition, so as to realize the complete independent calibration of the dual-axis parameters of the accelerometer, solve the weighting coefficient and zero drift of each axis separately, thereby calibrating the sensitivity of each axis, eliminating the calibration distortion caused by the mixing of parameters between axes, and adapting to the orthogonal dual-axis motion calibration scenario.

[0015] (3) The present invention can be cyclically calibrated under different hypergravity G values, and zero drift can be re-acquired and corresponding sensitivity parameters can be calibrated under each working condition. It can accurately match the stress deformation, zero offset and sensitivity drift of the accelerometer under hypergravity environment, and eliminate the systematic error caused by applying normal gravity parameters to hypergravity working conditions.

[0016] (4) The present invention performs weighted fusion of the displacement signals of the encoder and the laser displacement sensor, and adaptively allocates the weights of the two signals, thereby suppressing the mechanical hysteresis error of the encoder and the environmental noise error of the laser displacement sensor, and obtaining high-precision real-time displacement.

[0017] (5) Both drive motors of the dual-axis linear module of the present invention use frequency converters to output compensation torque to achieve drive control, which cancels the additional gravity torque generated by the high gravity of the rotor, greatly reduces the positioning static error of the drive motor, suppresses continuous oscillation, avoids rotor step failure, improves the control accuracy of the position of the dual-axis linear module under hypergravity environment, and the torque compensation takes into account both the rotor gravity torque and the load torque, which can be adapted to different loads and different hypergravity G values, and is suitable for linear module servo drive systems of various hypergravity centrifuge equipment. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the structure of the accelerometer calibration device of the present invention.

[0019] Figure 2 This is a block diagram illustrating the control principle of the accelerometer calibration device of the present invention.

[0020] Reference numerals: 1-Workbench, 2-Dual-axis linear module, 3-X-axis displacement sensor bracket, 4-Y-axis displacement sensor bracket, 5-X-axis laser displacement sensor, 6-Y-axis laser displacement sensor, 7-Vertical cross plate, 8-Square reinforced top plate, 9-Acceleration sensor to be calibrated, 10-Calibration controller, 21-Drive motor, 22-X-axis encoder, 23-Y-axis encoder, 24-Frequency controller, 31-Vertical plate, 32-Reinforcement rib, 33-Horizontal mounting plate. Detailed Implementation

[0021] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0022] See Figure 1 and Figure 2 The accelerometer calibration device is suitable for use in centrifugal environments under extreme gravity. It includes a worktable 1, a dual-axis linear module 2, two X-axis displacement sensor brackets 3, two Y-axis displacement sensor brackets 4, two sets of X-axis laser displacement sensors 5, two sets of Y-axis laser displacement sensors 6, and a calibration controller 10. The dual-axis linear module 2 is fixedly connected to the center of the worktable 1. The dual-axis linear module 2 is composed of an X-axis linear module and a Y-axis linear module. The drive motor 21 of the X-axis linear module is equipped with an X-axis encoder 22, and the drive motor 21 of the Y-axis linear module is equipped with a Y-axis encoder 23. A cross-shaped vertical cross plate 7 is fixedly connected to the horizontal slider at the end of the dual-axis linear module 2. A square reinforcing top plate 8 is fixedly connected to the top of the cross-shaped vertical cross plate 7. The square reinforcing top plate 8 is used to raise the cross-shaped vertical cross plate 7. To improve stability and enhance the positioning accuracy of the sensitive axis of the accelerometer to be calibrated, the X-axis vertical plate and Y-axis vertical plate of the cross vertical plate 7 are parallel to the X-axis and Y-axis of the dual-axis linear module 2, respectively; four identical accelerometers 9 to be calibrated are installed in pairs on the vertical surfaces of the X-axis vertical plate and the Y-axis vertical plate, respectively. The sensitive axis of the accelerometer 9 to be calibrated installed on the X-axis vertical plate is parallel to the X-axis vertical plate, and the sensitive axis of the accelerometer 9 to be calibrated installed on the Y-axis vertical plate is parallel to the Y-axis vertical plate. Two X-axis displacement sensor brackets 3 and two Y-axis displacement sensor brackets 4 are fixedly connected to the worktable 1 and located on the outer periphery of the dual-axis linear module 2. The two X-axis displacement sensor brackets 3 are symmetrical about the Y-axis of the dual-axis linear module 2, and the two Y-axis displacement sensor brackets 4 are symmetrical about the X-axis of the dual-axis linear module 2. Two sets of X-axis laser displacement sensors 5 are respectively installed on the two X-axis displacement sensor brackets 3 and are horizontally oriented towards the cross-shaped vertical cross plate 7. Two sets of Y-axis laser displacement sensors 6 are respectively installed on the two Y-axis displacement sensor brackets 4 and are horizontally oriented towards the cross-shaped vertical cross plate 7. Both the X-axis displacement sensor bracket 3 and the Y-axis displacement sensor bracket 4 include a vertical plate 31, a reinforcing rib 32, and a horizontal mounting plate 33. The horizontal mounting plate 33 passes horizontally through the vertical plate 31. A set of X-axis laser displacement sensors 5 or a set of Y-axis laser displacement sensors 6 are mounted on the top surface of the horizontal mounting plate 33 located inside the vertical plate 31. Each set of X-axis laser displacement sensors 5 and each set of Y-axis laser displacement sensors 6 includes three laser displacement sensors located at the same horizontal height. The reinforcing rib 32 is vertically fixed to the outer surface of the vertical plate 31, and the top of the reinforcing rib 32 is fixedly connected to the horizontal mounting plate 33 on the outer side of the vertical plate 31. Two sets of X-axis laser displacement sensors 5, two sets of Y-axis laser displacement sensors 6, and the acceleration sensor to be calibrated 9 are all electrically connected to the calibration controller 10; the two drive motors 21 of the dual-axis linear module 2 and their X-axis encoders 22 and Y-axis encoders 23 are all electrically connected to the frequency converter 24 of the dual-axis linear module 2, and the frequency converter 24 is electrically connected to the calibration controller 10.

[0023] A calibration method for accelerometers applicable to centrifugal environments with centrifugation under extreme gravity includes the following steps: (1) Place the acceleration sensor calibration device, except for the calibration controller 10 and the frequency converter 24 of the dual-axis linear module 2, in the basket of the centrifuge. Place the calibration controller 10 and the frequency converter 24 outside the centrifuge. Start the centrifuge and set the acceleration G value. (2) After the centrifuge starts normally, the calibration controller 10 controls the drive motor 21 of the X-axis linear module to reciprocate at the set speed. The displacement signal fed back to the calibration controller 10 by the X-axis encoder 22 is as follows: The displacement signals fed back to the calibration controller 10 by the two sets of X-axis laser displacement sensors 5 are as follows: The two are weighted and fused to obtain high-precision real-time X-axis displacement. , see the following formula (1) for details: (1); In equation (1), The X-axis weighting coefficient, with a value of 0 to 1, is calculated based on the inverse ratio of the mean square error of the two types of sensors by simultaneously collecting time-series data from the X-axis encoder 22 and the X-axis laser displacement sensor 5 under a hypergravity environment with a set hypergravity acceleration G value. Similarly, after the centrifuge starts normally, the calibration controller 10 controls the drive motor 21 of the Y-axis linear module to reciprocate at the set speed, and calculates the high-precision real-time displacement of the Y-axis using the following formula (2). : (2); In equation (2), The Y-axis weighting coefficient, with a value of 0 to 1, is calculated based on the inverse ratio of the mean square error of the two types of sensors by simultaneously collecting time-series data from the Y-axis encoder 23 and the Y-axis laser displacement sensor 6 under a hypergravity environment with a set hypergravity acceleration G value. This represents the displacement signal fed back from the Y-axis encoder 23 to the calibration controller 10; The displacement signals from the two sets of Y-axis laser displacement sensors 6 are fed back to the calibration controller 10. (3) The calibration controller 10 calculates the high-precision real-time X-axis acceleration using equation (3). and high-precision Y-axis real-time acceleration ; (3); In equation (3), It represents time and is a continuous time-series variable; (4) The calibration controller 10 constructs a linear relationship between the electrical signal output by the accelerometer 9 to be calibrated and the real-time acceleration, as shown in the following formula (4): (4); In equation (4), When the X-axis linear module performs reciprocating motion, the electrical signal output by the acceleration sensor 9 to be calibrated; When the Y-axis linear module performs reciprocating motion, the electrical signal output by the accelerometer 9 to be calibrated; and These represent the sensitivity of the accelerometer 9 to be calibrated mounted on the X-axis vertical plate and the sensitivity of the accelerometer 9 to be calibrated mounted on the Y-axis vertical plate, respectively. and These represent the noise levels of the accelerometer 9 to be calibrated mounted on the X-axis vertical plate and the accelerometer 9 to be calibrated mounted on the Y-axis vertical plate, respectively. and These represent the zero-point drift of the accelerometer 9 to be calibrated mounted on the X-axis vertical plate and the zero-point drift of the accelerometer 9 to be calibrated mounted on the Y-axis vertical plate, respectively. and Under hypergravity conditions with a set hypergravity acceleration G value, the dual-axis linear module 2 is kept stationary, and the electrical signals of the acceleration sensors 9 to be calibrated, mounted on the X-axis vertical plate and the Y-axis vertical plate, are continuously collected within a set time period (10-20 seconds). , Then, the electrical signal sequences acquired along the X and Y axes are subjected to moving average filtering to remove noise. and Finally, the arithmetic mean of the filtered X-axis and Y-axis electrical signal sequences is taken to obtain the zero-point drift under the set hypergravity acceleration G value. and ; The calibration controller 10 obtains different accelerations by continuously changing the rotational speeds of the drive motors 21 of the X-axis linear module and the Y-axis linear module. or The corresponding electrical signal or Multiple sets of data were fitted and solved to obtain the set hypergravity acceleration G value. and Before fitting, zero-point drift on each axis must be removed. and Filtering to eliminate noise and Then through multiple groups Linear fitting calculation Through multiple groups Linear fitting calculation ; (5) After adjusting the hypergravity acceleration G value of the hypergravity centrifuge, calibrate the controller 10 and repeat steps (2)-(4), and re-acquire and determine the zero-point drift corresponding to the hypergravity acceleration G value. and The linear relationship between the electrical signal output by the accelerometer 9 to be calibrated and the real-time acceleration under different hypergravity acceleration G values ​​was obtained.

[0024] In this dual-axis linear module 2, both drive motors 21 are driven by a frequency converter 24 that outputs a compensation torque to achieve drive control. The specific calculation formula is shown in the following formula (5): (5); In equation (5), Representing the load torque, the frequency converter 24 collects the three-phase current of the stator of the drive motor 21 in real time and estimates the load torque under the current hypergravity acceleration G value based on the vector control model; This represents the gravitational torque generated by the rotor under hypergravity conditions; The rotor mass of drive motor 21 is represented by the rotor mass. This represents the G-value, which indicates the acceleration due to gravity set in the centrifuge. This represents the rotor eccentricity of the drive motor 21.

[0025] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. An acceleration sensor calibration device suitable for use in a high gravity centrifuge environment, characterized by: It includes a worktable, a dual-axis linear module, two X-axis displacement sensor brackets, two Y-axis displacement sensor brackets, two sets of X-axis laser displacement sensors, two sets of Y-axis laser displacement sensors, and a calibration controller; The dual-axis linear module is fixedly connected to the center of the worktable. The dual-axis linear module is composed of an X-axis linear module and a Y-axis linear module spliced ​​together. The drive motor of the X-axis linear module is equipped with an X-axis encoder, and the drive motor of the Y-axis linear module is equipped with a Y-axis encoder. A vertical positioning bracket is fixedly connected to the horizontal slider at the end of the dual-axis linear module. The acceleration sensor to be calibrated is fixedly connected to the vertical positioning bracket. The sensitive axis of the acceleration sensor to be calibrated is parallel to the X-axis or Y-axis of the dual-axis linear module. Two X-axis displacement sensor brackets and two Y-axis displacement sensor brackets are fixedly connected to the worktable and located on the outer periphery of the dual-axis linear module. The two X-axis displacement sensor brackets are symmetrical along the Y-axis of the dual-axis linear module, and the two Y-axis displacement sensor brackets are symmetrical along the X-axis of the dual-axis linear module. Two sets of X-axis laser displacement sensors are respectively installed on the two X-axis displacement sensor brackets and are horizontally oriented towards the vertical positioning brackets. Two sets of Y-axis laser displacement sensors are respectively installed on the two Y-axis displacement sensor brackets and are horizontally oriented towards the vertical positioning brackets. The two sets of X-axis laser displacement sensors, the two sets of Y-axis laser displacement sensors, and the acceleration sensor to be calibrated are all electrically connected to the calibration controller; the two drive motors of the dual-axis linear module and their X-axis encoders and Y-axis encoders are all electrically connected to the frequency converter of the dual-axis linear module, and the frequency converter is electrically connected to the calibration controller.

2. The acceleration sensor calibration device suitable for use in a high gravity centrifugal environment according to claim 1, characterized in that: The vertical positioning bracket is a cross-shaped vertical plate, with the X-axis and Y-axis vertical plates of the cross-shaped vertical plate being parallel to the X-axis and Y-axis of the dual-axis linear module, respectively. There are two sets of accelerometers to be calibrated, both sets being of the same model. These two sets of accelerometers are respectively mounted on the vertical surfaces of the X-axis and Y-axis vertical plates. The sensitive axis of the accelerometer mounted on the X-axis vertical plate is parallel to the X-axis vertical plate, and the sensitive axis of the accelerometer mounted on the Y-axis vertical plate is parallel to the Y-axis vertical plate.

3. The acceleration sensor calibration device suitable for use in a high gravity centrifugal environment according to claim 2, characterized in that: A square reinforcing top plate is fixedly connected to the top of the vertical cross plate.

4. The acceleration sensor calibration device suitable for use in a high gravity centrifugal environment according to claim 1, wherein: Both the X-axis displacement sensor bracket and the Y-axis displacement sensor bracket include a vertical plate, a reinforcing rib, and a horizontal mounting plate. The horizontal mounting plate passes horizontally through the vertical plate. A set of X-axis laser displacement sensors or a set of Y-axis laser displacement sensors are mounted on the top surface of the horizontal mounting plate located inside the vertical plate. The reinforcing rib is vertically fixed to the outer surface of the vertical plate, and the top of the reinforcing rib is fixedly connected to the horizontal mounting plate on the outer side of the vertical plate.

5. The acceleration sensor calibration device suitable for use in a high gravity centrifugal environment according to claim 4, characterized in that: Each of the two sets of X-axis laser displacement sensors and the two sets of Y-axis laser displacement sensors includes multiple laser displacement sensors mounted on corresponding horizontal mounting plates at the same horizontal height.

6. A method for calibrating an accelerometer using the accelerometer calibration device suitable for centrifugal acceleration environments as described in claim 2, characterized in that: Specifically, it includes the following steps: (1) Place the part of the accelerometer calibration device, except for the calibration controller and the dual-axis linear module frequency converter, in the basket of the centrifuge. Place the calibration controller and the frequency converter outside the centrifuge. Start the centrifuge and set the acceleration G value. (2) After the centrifuge starts normally, the calibration controller controls the drive motor of the X-axis linear module to reciprocate at the set speed. The displacement signal fed back to the calibration controller by the X-axis encoder is: The displacement signals fed back to the calibration controller by the two sets of X-axis laser displacement sensors are: The two are weighted and fused to obtain high-precision real-time X-axis displacement. , see the following formula (1) for details: （1）； In equation (1), The X-axis weighting coefficient, with a value of 0 to 1, is calculated based on the inverse ratio of the mean square error of the two types of sensors by simultaneously collecting time-series data from the X-axis encoder and the X-axis laser displacement sensor under a hypergravity environment with a set hypergravity acceleration G. Similarly, after the super gravity centrifuge is started normally, the Y-axis linear module driving motor is controlled by the calibration controller to reciprocate at a set rotating speed, and high-precision real-time displacement of the Y-axis is calculated through the following formula (2) : （2）； In equation (2), The Y-axis weighting coefficient, with a value of 0 to 1, is calculated based on the inverse ratio of the mean square error of the two types of sensors by simultaneously collecting time-series data from the Y-axis encoder and the Y-axis laser displacement sensor under a hypergravity environment with a set hypergravity acceleration G. This represents the displacement signal fed back from the Y-axis encoder to the calibration controller; This represents the displacement signals fed back to the calibration controller from two sets of Y-axis laser displacement sensors; (3) The calibration controller calculates the high-precision X-axis real-time acceleration by formula (3) and the high-precision Y-axis real-time acceleration ; （3）； In formula (3), t represents time, which is a continuous time variable; (4) The calibration controller constructs a linear relationship between the electrical signal output by the accelerometer to be calibrated and the real-time acceleration, as shown in the following formula (4): （4）； In equation (4), The electrical signal output by the accelerometer sensor to be calibrated when the X-axis linear module performs reciprocating motion; The electrical signal output by the accelerometer sensor to be calibrated when the Y-axis linear module performs reciprocating motion; and These represent the sensitivity of the accelerometer to be calibrated mounted on the X-axis vertical plate and the sensitivity of the accelerometer to be calibrated mounted on the Y-axis vertical plate, respectively. and These represent the zero-point drift of the accelerometer to be calibrated mounted on the X-axis vertical plate and the zero-point drift of the accelerometer to be calibrated mounted on the Y-axis vertical plate, respectively. and These represent the noise levels of the accelerometer to be calibrated mounted on the X-axis vertical plate and the accelerometer to be calibrated mounted on the Y-axis vertical plate, respectively. The calibration controller obtains different accelerations by continuously changing the speeds of the drive motors of the X-axis and Y-axis linear modules. or The corresponding electrical signal or Multiple sets of data were fitted and solved to obtain the set hypergravity acceleration G value. and ; (5) After adjusting the hypergravity acceleration G value of the hypergravity centrifuge, the calibration controller repeats steps (2)-(4) to calibrate the linear relationship between the electrical signal output by the acceleration sensor to be calibrated and the real-time acceleration under different hypergravity acceleration G values.

7. The calibration method of claim 6, wherein: The and Under a hypergravity environment with a set hypergravity acceleration G value, the dual-axis linear module is kept stationary while continuously acquiring electrical signals from the accelerometers to be calibrated mounted on the X-axis vertical plate and the accelerometer to be calibrated mounted on the Y-axis vertical plate within a set time period, thus obtaining... , Then, the electrical signal sequences acquired along the X and Y axes are subjected to moving average filtering to remove noise. and Finally, the arithmetic mean of the filtered X-axis and Y-axis electrical signal sequences is taken to obtain the zero-point drift under the set hypergravity acceleration G value. and After adjusting the acceleration G value of the centrifuge, repeat the above steps to re-acquire and determine the zero-point drift corresponding to the acceleration G value. and .

8. The calibration method of claim 6, wherein: Both drive motors of the dual-axis linear module are driven by a frequency converter that outputs a compensation torque to achieve drive control. The specific calculation formula is shown in the following formula (5): （5）； In equation (5), Representing the load torque, the frequency converter collects the three-phase current of the drive motor stator in real time and estimates the load torque under the current hypergravity acceleration G value based on the vector control model; This represents the gravitational torque generated by the rotor under hypergravity conditions; Represents the rotor mass of the drive motor; This represents the G-value, which indicates the acceleration due to gravity set in the centrifuge. This represents the rotor eccentricity of the drive motor.

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