CN113484538A - Acceleration measurement method based on anti-magnetic suspension mechanical system - Google Patents
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- G01P15/00—Measuring acceleration; Measuring deceleration; Measuring shock, i.e. sudden change of acceleration
- G01P15/02—Measuring acceleration; Measuring deceleration; Measuring shock, i.e. sudden change of acceleration by making use of inertia forces using solid seismic masses
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- G01P15/00—Measuring acceleration; Measuring deceleration; Measuring shock, i.e. sudden change of acceleration
- G01P15/02—Measuring acceleration; Measuring deceleration; Measuring shock, i.e. sudden change of acceleration by making use of inertia forces using solid seismic masses
- G01P15/08—Measuring acceleration; Measuring deceleration; Measuring shock, i.e. sudden change of acceleration by making use of inertia forces using solid seismic masses with conversion into electric or magnetic values
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Abstract
The invention provides an acceleration measuring method based on an anti-magnetic suspension mechanical system, which comprises the following steps of obtaining external acceleration a; secondly, constructing an acceleration sensitive module, and suspending the anti-magnetic mass body by using a magnetic potential trap to obtain the position movement deltax of the anti-magnetic mass body brought by the external acceleration a; thirdly, constructing a position measuring module to realize the conversion from the change of the laser light intensity delta I to the voltage delta V; and fourthly, calculating the actual external acceleration a according to the output measured voltage delta V variation. The invention is different from the existing suspension system, optical suspension, electrostatic suspension, superconducting suspension and the like in physical principle by providing an anti-magnetic suspension acceleration sensitivity mode, does not need external energy input compared with the electrostatic suspension and the optical suspension, has the lowest parameter noise, reduces the main noise source for limiting the acceleration sensitivity, and simultaneously meets the requirement of working at room temperature or low temperature compared with the superconducting suspension.
Description
Technical Field
The invention relates to the technical field of acceleration measurement, in particular to an acceleration measurement method based on an anti-magnetic suspension mechanical system.
Background
High-precision accelerometers are core technologies for realizing applications such as inertial navigation and gravity measurement, and current accelerometers include cold atom accelerometers, neutron accelerometers, quartz accelerometers, suspension accelerometers, micro-electro-mechanical systems (MEMS) accelerometers, opto-mechanical accelerometers, optical suspension accelerometers, suspension accelerometers and the like. The suspension accelerometer has the highest precision in principle, the core of the suspension accelerometer is a mass body suspended by an electromagnetic field, according to the generalized relativity theory, the acceleration brings the movement of the position of the suspension body, the acceleration can be sensed by measuring the position, and the suspension accelerometer is not in direct contact with the environment, so that the suspension accelerometer has very low noise in physical principle, has ultrahigh sensitivity and cannot be replaced by other prior art.
The current suspension accelerometer comprises three methods of laser suspension, electrostatic suspension and superconducting suspension, wherein the laser suspension is limited by the size of a mass body, the mass body has the maximum bandwidth in a suspension system, but the sensitivity is relatively low (10-7g/Hz1/2 level), the electrostatic suspension is the most developed technology, the suspension is controlled by relying on a feedback circuit, the sensitivity is limited by electronic noise (10-9g/Hz1/2 level), the superconducting suspension is a brand new technology which is recently proposed, the theoretical sensitivity can reach (10-10g/Hz1/2 level), and the superconducting suspension requires the system to work under the low-temperature condition (lower than 10K) and limits the requirement for realizing a small-sized movable low-power consumption application scene in the future.
In addition, the superconducting suspension technology and core is a superconducting potential well, the suspended mass body is a magnetic material, and the magnetic field of the mass body is suspended under the action of the superconducting Meissner effect by lowering the temperature of the potential well to be below the superconducting transition temperature, so that the acceleration sensing capability is realized.
The problems are that: the existing superconducting material needs a low-temperature condition (10K), a low-temperature system is usually huge in size and high in power consumption, can only be used in a laboratory or a special indoor environment at present, cannot meet the application scene of mobility, portability and particularly low power consumption, and greatly limits the practical application of the technology.
Disclosure of Invention
The present invention provides an acceleration measurement method based on an anti-magnetic levitation mechanical system, which solves the problems of the background art, and the present invention provides an anti-magnetic levitation acceleration which is physically different from the existing levitation systems, such as optical levitation, electrostatic levitation, superconducting levitation, etc., thereby having the highest absolute sensitivity, and compared with the electrostatic levitation and optical levitation, the present invention does not require external energy input, has the lowest parameter noise, and reduces the main noise source limiting the acceleration sensitivity.
In order to achieve the purpose, the invention is realized by the following technical scheme: an acceleration measurement method based on an anti-magnetic suspension mechanical system comprises the following steps:
firstly, acquiring external acceleration a;
secondly, constructing an acceleration sensitive module
Forming a diamagnetic suspension potential well by using a permanent magnet, suspending a diamagnetic mass body in the diamagnetic suspension potential well, and obtaining the position movement deltax of the diamagnetic mass body brought by external acceleration a;
thirdly, constructing a position measurement module
S3-1, inputting a laser signal to the diamagnetic mass body, and obtaining laser intensity change delta I caused by the position movement delta x when the diamagnetic mass body is output by the laser based on the self-generated focusing effect of the diamagnetic mass body;
s3-2, converting the laser light intensity change delta I into voltage delta V through a photoelectric conversion module;
and fourthly, calculating the actual external acceleration a according to the output measured voltage delta V variation.
As an improvement of the acceleration measurement method based on the anti-magnetic levitation mechanical system, in the second step, a specific implementation manner of constructing an acceleration sensitive module to obtain the position movement δ x is as follows:
s2-1, forming a diamagnetic levitation potential well through a permanent magnet to obtain a diamagnetic levitation magnetic field B (x);
s2-2, based on the diamagnetic suspension principle, obtaining diamagnetic potential energy U (x) by using diamagnetic interaction energy generated by spin magnetic moments in diamagnetic materials, wherein the diamagnetic potential energy U (x) under the vacuum condition is calculated according to the following formula:
wherein mgz is the gravitational potential energy of the diamagnetic material, chi is the magnetic susceptibility of the diamagnetic material,
is diamagnetic interaction, where μ 0 is the vacuum permeability and V is the diamagnetic mass volume;
s2-3, suspending the diamagnetic mass body in the diamagnetic suspension potential well, and obtaining the position movement δ x of the diamagnetic mass body brought by the external acceleration a when sensing the external acceleration a and the mass m of the diamagnetic mass body, wherein the position movement δ x is calculated by the following formula:
in the formula (I), the compound is shown in the specification,
is a partial differential operator.
As an improvement of the acceleration measuring method based on the anti-magnetic levitation mechanical system, in step S3-1, the specific implementation manner of obtaining the laser intensity change δ I is as follows:
at least one group of optical fibers for transmitting laser input signals are arranged on two sides of the diamagnetic mass body, wherein every two optical fibers are oppositely parallel, and transmission is realized through the focusing effect of the diamagnetic mass body;
based on the position movement deltax of the diamagnetic mass body under the action of the external acceleration a, the change deltaI of the laser light intensity in the optical fiber when the diamagnetic mass body is output is obtained;
in step S3-2, the specific implementation manner of implementing the change from the laser intensity δ I to the voltage δ V change amount by the photoelectric conversion module is as follows:
the photoelectric conversion module arranged in the photoelectric detector is used for converting a light intensity signal of laser light intensity change delta I into a voltage signal so as to measure, and the calculation mode is as follows:
in the formula, δ V is a measured voltage variation amount, and ξ is a displacement light intensity conversion coefficient.
As an improvement of the acceleration measurement method based on the anti-magnetic levitation mechanical system, in the fourth step, the calculation method for calculating the actual external acceleration is as follows:
wherein a is the actual external acceleration,
for partial differential operator, xi is the conversion coefficient of displacement light intensity, U (x) is the diamagnetic potential energy, δ V is the measured voltage variation, and m is the diamagnetic mass.
In one possible implementation manner of the acceleration measuring method provided by the present invention, based on the second step, before the permanent magnet forms the anti-magnetic levitation potential well, the permanent magnet needs to be processed, and the specific implementation manner includes:
firstly, processing a permanent magnet by using a numerical control machine tool, and magnetizing the permanent magnet according to a design direction;
secondly, carrying out combined fine adjustment on the permanent magnet;
finally, the permanent magnet is encapsulated by epoxy.
As an improvement of the acceleration measurement method based on the anti-magnetic levitation mechanical system, in the third step, before inputting the laser signal to the anti-magnetic mass body, the position of the optical fiber for transmitting the laser input signal needs to be fixed, and the specific fixing mode is as follows:
firstly, moving the position of the optical fiber to two sides of the diamagnetic mass body through a position operation table for adjustment;
secondly, when the dependence of the light intensity signal and the position of the optical fiber reaches the maximum, the optical fiber is fixed.
As an improvement of the acceleration measurement method based on the anti-magnetic levitation mechanical system, the optical fiber is fixed in the following manner:
fixed thereto by epoxy resin or adhesive, or
It is fixed by a piezoelectric positioning device.
As an improvement of the acceleration measuring method based on the anti-magnetic suspension mechanical system, the anti-magnetic mass body is made of a transparent anti-magnetic material, wherein the anti-magnetic material is graphite, quartz, organic glass PMMA or an anti-magnetic high polymer material;
the diamagnetic mass body comprises an upper magnet layer and a lower magnet layer, and the polarization directions of the upper magnet layer and the lower magnet layer are opposite to each other so as to form a stable diamagnetic levitation potential well at the geometric center position of the permanent magnet;
and a through hole is formed in the geometric center direction of the upper magnet layer, so that a diamagnetic restriction area in the horizontal direction is formed.
Compared with the prior art, the invention has the beneficial effects that:
1. the invention is different from the existing suspension system, optical suspension, electrostatic suspension, superconducting suspension and the like in the physical principle by providing the diamagnetic suspension acceleration, thereby having the highest absolute sensitivity, having the lowest parameter noise and reducing the main noise source for limiting the acceleration sensitivity compared with the electrostatic suspension and the optical suspension without external energy input, and being capable of independently and effectively reducing the system power consumption by not depending on the low-temperature environment through the provided diamagnetic suspension acceleration and meeting the working characteristic in the room temperature or the low-temperature environment compared with the superconducting suspension;
2. the invention constructs the acceleration sensitive part by the diamagnetic suspension system, thereby converting the acceleration into the position change signal, converting the obtained displacement change signal into the change of the transmission light intensity based on the laser measurement, and finally realizing the conversion from the light intensity signal to the voltage by utilizing the photoelectric detection technology to finish the measurement mode, thereby having higher detection efficiency and having the characteristics of room temperature work, small volume and high sensitivity compared with the prior art;
3. by adopting a mode of forming a diamagnetic confinement potential well based on a permanent magnet, the electrostatic suspension and the optical suspension are distinguished, and a magnetic potential well without any external energy consumption is constructed;
4. the diamagnetic mass body is designed into an upper magnet layer and a lower magnet layer with opposite polarization directions, so that on one hand, the lower magnet layer converges magnetic lines of force in a central area to generate a magnetic field and a magnetic field gradient in the vertical direction, generate a diamagnetic force for overcoming the gravity of the diamagnetic mass and provide constraint in the vertical direction; on the other hand, the restriction in the horizontal direction is provided by forming the through hole in the geometric center direction of the upper layer magnet, so that a stable magnetic potential well is formed, the defect that the conventional superconducting suspension accelerometer can only be used in a low-temperature environment is overcome, and the multi-scene application of the antimagnetic suspension accelerometer is realized.
Drawings
The disclosure of the present invention is illustrated with reference to the accompanying drawings. It is to be understood that the drawings are designed solely for purposes of illustration and not as a definition of the limits of the invention, for which like reference numerals are used to indicate like parts. Wherein:
FIG. 1 is a schematic diagram of an embodiment of an anti-magnetic levitation accelerometer;
FIG. 2 is a schematic flow chart of an acceleration measurement method of an anti-magnetic levitation accelerometer according to an embodiment of the present invention;
FIG. 3 is a schematic diagram of the operation of the position measurement module of the anti-magnetic levitation accelerometer according to an embodiment of the invention;
FIG. 4 is a schematic diagram of an embodiment of the present invention, in which a via hole is formed in the geometric center direction of the upper magnet layer to form a diamagnetic confinement region in the horizontal direction;
FIG. 5 is a first graph of the magnetic confinement potential energy of the diamagnetic mass in the z-direction according to an embodiment of the present invention;
fig. 6 is a second graph of the magnetic confinement potential energy of the diamagnetic mass in the z direction according to the embodiment of the invention;
FIG. 7 is a graph of the magnetic confinement potential energy of the diamagnetic mass in horizontal x and y directions according to an embodiment of the invention;
fig. 8 is a schematic view of an implementation scenario when an optical fiber is fixed according to an embodiment of the present invention;
fig. 9 is a typical acceleration noise power spectrum according to the prior art in an embodiment of the present invention.
Detailed Description
It is easily understood that according to the technical solution of the present invention, a person skilled in the art can propose various alternative structures and implementation ways without changing the spirit of the present invention. Therefore, the following detailed description and the accompanying drawings are merely illustrative of the technical aspects of the present invention, and should not be construed as all of the present invention or as limitations or limitations on the technical aspects of the present invention.
As shown in fig. 1-2, as an embodiment of the present invention, the present invention provides a technical solution: an acceleration measurement method based on an anti-magnetic suspension mechanical system comprises the following steps:
firstly, acquiring external acceleration a;
secondly, constructing an acceleration sensitive module
Forming a diamagnetic levitation potential well by using a permanent magnet, suspending a diamagnetic mass body in the diamagnetic levitation potential well to obtain the position movement or sliding distance delta x of the diamagnetic mass body brought by external acceleration a, wherein the specific implementation mode of constructing an acceleration sensitive module to obtain the position movement delta x is as follows:
s2-1, forming a diamagnetic levitation potential well through a permanent magnet to obtain a diamagnetic levitation magnetic field B (x), wherein it can be understood that electrostatic levitation and optical levitation are distinguished by adopting a mode of designing a diamagnetic confinement potential well based on the permanent magnet to construct a magnetic potential well without any external energy consumption;
s2-2, the diamagnetic suspension accelerometer is based on the diamagnetic suspension principle, and it can be understood that the diamagnetic suspension principle is to utilize diamagnetic mutual conduction generated by the spin magnetic moment in the diamagnetic material to realize the suspension of the mass body, and the diamagnetic suspension accelerometer is different from the superconducting suspension accelerometer by utilizing the superconducting Meissner effect, and simultaneously, coulomb force and dielectric force adopted by the diamagnetic suspension accelerometer, electrostatic suspension accelerometer and laser suspension accelerometer are completely different, so diamagnetic interaction energy generated by the spin magnetic moment in the diamagnetic material can be utilized to obtain diamagnetic potential energy U (x), wherein the diamagnetic potential energy U (x) under the vacuum condition has the following calculation formula:
wherein mgz is the gravitational potential energy of the diamagnetic material, m is the mass, g is the gravitational acceleration, z is the z-direction position,
the diamagnetic material is a diamagnetic interaction of a diamagnetic suspension system, wherein mu 0 is vacuum permeability, V is volume of a diamagnetic mass, and x is magnetic susceptibility of a diamagnetic material, and it is required to be noted that the magnetic susceptibility x of a special diamagnetic material is a negative value, and the diamagnetic material is preferably graphite, quartz, organic glass (PMMA) and most diamagnetic high polymer materials;
as the understanding of the diamagnetic action in the diamagnetic suspension, the diamagnetic action provides the aim of offsetting gravity to achieve suspension, and the diamagnetic suspension is different from laser or electrostatic suspension in that the diamagnetic suspension does not need external energy input and achieves the characteristic of no power consumption, and the diamagnetic suspension can be realized at any temperature, does not need the ultralow temperature environment required by superconducting suspension, and does not have the power consumption generated in the process of maintaining the ultralow temperature;
s2-3, suspending the diamagnetic mass body in the diamagnetic suspension potential well, and obtaining the position movement δ x of the diamagnetic mass body brought by the external acceleration a when sensing the external acceleration a and the mass m of the diamagnetic mass body, wherein the position movement δ x is calculated by the following formula:
as shown in fig. 3, the working principle of the position measurement module is shown, therefore, in the third step, the position measurement module S3-1 is constructed, a laser signal is input to the diamagnetic mass, and a laser intensity change δ I caused by a position movement δ x when the laser outputs the diamagnetic mass is obtained based on the self-generated focusing effect of the diamagnetic mass, wherein the specific implementation manner of obtaining the laser intensity change δ I is as follows: at least one group of optical fibers for transmitting laser input signals are arranged on two sides of the diamagnetic mass, wherein every two optical fibers are relatively parallel;
it should be noted that, the invention designs the diamagnetic mass body into a sphere, adopts a laser detection method to form optical fibers, and the two optical fibers are respectively positioned at two sides of the diamagnetic mass body, and realizes transmission through the focusing effect of the diamagnetic mass body, when the diamagnetic mass body generates position deviation deltax under the action of acceleration, the laser intensity in the optical fiber outputting the diamagnetic mass body is changed deltaI;
s3-2, the conversion from laser light intensity change delta I to voltage delta V is realized through the photoelectric conversion module, and the specific implementation mode is as follows: the photoelectric conversion module arranged in the photoelectric detector is used for converting a light intensity signal of laser light intensity change delta I into a voltage signal so as to measure, and the calculation mode is as follows:
in the formula, δ V is the measured voltage variation, and ξ is the displacement light intensity conversion coefficient;
fourthly, calculating the actual external acceleration a according to the output measured voltage delta V variable quantity, wherein the specific implementation calculation formula is as follows:
wherein a is the actual external acceleration,
is a partial differential operator, ξ is the displacement intensity conversion coefficient, U (x) isDiamagnetic potential energy, δ V is the measured voltage change, and m is the diamagnetic mass.
Based on the second step, before the permanent magnet forms the anti-magnetic levitation potential well, the permanent magnet needs to be processed, and the specific embodiment includes:
firstly, processing a permanent magnet by using a numerical control machine tool, and magnetizing the permanent magnet according to a design direction;
secondly, performing combined fine adjustment on the permanent magnet, preferably installing and combining the permanent magnet through a metal supporting structure, fine adjusting the position of the permanent magnet through screws and the like, and after the permanent magnet is installed;
finally, the permanent magnet is encapsulated by epoxy.
It should be noted that, in the third step, before inputting the laser signal to the diamagnetic mass, the position of the optical fiber that emits the laser input signal needs to be fixed, and the specific fixing method is as follows:
firstly, moving the optical fiber position to two sides of a spherical diamagnetic mass body through a position operation table for adjustment;
secondly, when the dependence of the light intensity signal and the position of the optical fiber reaches the maximum, the optical fiber is fixed.
Based on the understanding of the above technical concept, the fixing manner of the optical fiber is preferably two: on the one hand, passive fixation, i.e., permanent fixation of the fiber position using epoxy or other adhesive; on the other hand, the position of the optical fiber is finely adjusted in real time according to the change of the environment through a piezoelectric positioning device, so that the optical fiber is positioned at the optimal working point, as shown in fig. 8, an implementation scene when the optical fiber at the optimal working point is fixed is shown, in the specific implementation, a ball body suspended in the center of a diamagnetic suspension potential well is a diamagnetic mass body and is made of a transparent diamagnetic material, when a laser signal (invisible) is input from the left side, the laser signal is converged by the diamagnetic mass body, the optical fiber at the right side is output, and the laser signal is further transmitted to a photoelectric detection system.
As shown in fig. 4, the design of the anti-levitating potential well is shown:
the diamagnetic mass body is made of a transparent diamagnetic material, wherein the preferable diamagnetic material is graphite or quartz or organic glass PMMA or a diamagnetic high polymer material;
the diamagnetic mass body is divided into an upper-layer structure and a lower-layer structure, namely, the diamagnetic mass body comprises an upper magnet layer and a lower magnet layer, the polarization directions of the upper magnet layer and the lower magnet layer are opposite, so that a stable diamagnetic suspension potential well is formed at the geometric center position of the permanent magnet.
In an embodiment of the present invention, it can be understood that, by designing the anti-magnetic mass body as an upper and a lower double-magnet layers with opposite polarization directions, on one hand, the lower magnet layer converges magnetic lines of force in a central region of the anti-magnetic levitation potential well to generate a magnetic field and a magnetic field gradient in a z direction, so as to provide an anti-magnetic force for overcoming gravity and provide a constraint in the z direction, and on the other hand, by forming a through hole in a geometric central direction of the upper magnet layer, a constraint in a horizontal direction x and y is provided, so as to achieve stable levitation in three directions, thereby forming a stable magnetic potential well, overcoming a defect that the existing superconducting levitation accelerometer can only be used in a low temperature environment, and achieving multi-scenario application of the anti-magnetic levitation accelerometer And the constraint position and the like can be adjusted according to the needs without difference in principle.
5-6, showing the curve of the magnetic confinement potential energy of the diamagnetic mass in the z direction, it should be noted that the minimum value of the magnetic confinement potential energy corresponds to the levitation position in the z direction;
as shown in fig. 7, a magnetic confinement potential energy curve of the diamagnetic mass in horizontal x and y directions is shown, and it should be noted that a zero value of the magnetic confinement potential energy curve is a magnetic confinement position.
As a second aspect of the present invention, an implementation method of an acceleration measurement environment is provided, where a vacuum environment is required for the operation of the anti-magnetic levitation system, and when the anti-magnetic levitation accelerometer is manufactured and then placed in a vacuum chamber, it can be understood that the vacuum environment reduces air resistance, thereby improving the dissipation performance of the anti-magnetic levitation mass body to achieve sensitive sensing of acceleration, it is known that a higher vacuum will generate a higher sensitivity, but in practice, the dissipation of the anti-magnetic levitation system is not limited to pressure, but also affected by magnetic damping, and according to the specific operation environment, therefore, the vacuum can meet the requirement of the acceleration measurement sensitivity at 10-3mbar to 10-5mbar, as shown in fig. 9, which shows the acceleration noise power spectrum of the anti-magnetic levitation system at the existing typical room temperature, it can be seen that the laser power is known to be 0.1mw, the vacuum degree is 10-3mbar, the working temperature is 300K, and the effective mass of the diamagnetic suspended mass body is 0.5 mg:
based on the implementation scenario set by the concept, a laser with small power fluctuation is applied in the measurement process, an optical fiber is accessed, then a light detector is used for detecting light intensity, the optical voltage is continuously measured by using a standard analog signal acquisition card, and the acceleration noise power spectrum of the diamagnetic suspension system is obtained, so that the diamagnetic suspension system can still realize the acceleration sensitivity lower than 10-9g/Hz1/2 within the frequency range of 1mHz to 10Hz in the room temperature environment even under the common vacuum condition. The invention is different from the existing suspension system, optical suspension, electrostatic suspension, superconducting suspension and the like in physical principle by providing the diamagnetic suspension acceleration, thereby having the highest absolute sensitivity, and compared with the electrostatic suspension and the optical suspension, the invention does not need external energy input, has the lowest parameter noise, and reduces the main noise source for limiting the acceleration sensitivity.
As another embodiment of the present invention, under the condition that the mode of constructing the acceleration sensitive module is not changed, the position measurement of the external acceleration a can be realized by the modes of a solid state quantum system, capacitance measurement or a superconducting interferometer, etc., and the present invention adopts laser measurement to convert the obtained displacement change signal into the change of the transmission light intensity, and finally utilizes the photoelectric detection technology to realize the conversion from the light intensity signal to the voltage, thereby completing the measurement mode.
Meanwhile, the invention provides a diamagnetic suspension system and a typical implementation mode of a diamagnetic suspension potential well, wherein diamagnetic suspension can be realized by combining permanent magnets with different shapes and sizes in various modes, and can be further combined with a superconducting magnet to realize stable suspension of diamagnetic substances.
The technical scope of the present invention is not limited to the above description, and those skilled in the art can make various changes and modifications to the above-described embodiments without departing from the technical spirit of the present invention, and such changes and modifications should fall within the protective scope of the present invention.
Claims (8)
1. An acceleration measurement method based on an anti-magnetic suspension mechanical system is characterized in that: the method comprises the following steps:
firstly, acquiring external acceleration a;
secondly, constructing an acceleration sensitive module
Forming a diamagnetic suspension potential well by using a permanent magnet, suspending a diamagnetic mass body in the diamagnetic suspension potential well, and obtaining the position movement deltax of the diamagnetic mass body brought by external acceleration a;
thirdly, constructing a position measurement module
S3-1, inputting a laser signal to the diamagnetic mass body, and obtaining laser intensity change delta I caused by the position movement delta x when the diamagnetic mass body is output by the laser based on the self-generated focusing effect of the diamagnetic mass body;
s3-2, converting the laser light intensity change delta I into voltage delta V through a photoelectric conversion module;
and fourthly, calculating the actual external acceleration a according to the output measured voltage delta V variation.
2. The acceleration measurement method based on the magnetic levitation resistant mechanical system as claimed in claim 1, wherein: in the second step, the specific implementation manner of constructing the acceleration sensitive module to obtain the position movement δ x is as follows:
s2-1, forming a diamagnetic levitation potential well through a permanent magnet to obtain a diamagnetic levitation magnetic field B (x);
s2-2, based on the diamagnetic suspension principle, obtaining diamagnetic potential energy U (x) by using diamagnetic interaction energy generated by spin magnetic moments in diamagnetic materials, wherein the diamagnetic potential energy U (x) under the vacuum condition is calculated according to the following formula:
wherein mgz is the gravitational potential energy of the diamagnetic material, chi is the magnetic susceptibility of the diamagnetic material,
for diamagnetic interaction, wherein, mu0Is the vacuum permeability, V is the diamagnetic mass volume;
s2-3, suspending the diamagnetic mass body in the diamagnetic suspension potential well, and obtaining the position movement δ x of the diamagnetic mass body brought by the external acceleration a when sensing the external acceleration a and the mass m of the diamagnetic mass body, wherein the position movement δ x is calculated by the following formula:
in the formula (I), the compound is shown in the specification,
is a partial differential operator.
3. The acceleration measurement method based on the magnetic levitation resistant mechanical system as claimed in claim 1, wherein: in step S3-1, the specific implementation of obtaining the laser intensity change δ I is:
at least one group of optical fibers for transmitting laser input signals are arranged on two sides of the diamagnetic mass body, wherein every two optical fibers are oppositely parallel, and transmission is realized through the focusing effect of the diamagnetic mass body;
based on the position movement deltax of the diamagnetic mass body under the action of the external acceleration a, the change deltaI of the laser light intensity in the optical fiber when the diamagnetic mass body is output is obtained;
in step S3-2, the specific implementation manner of implementing the change from the laser intensity δ I to the voltage δ V change amount by the photoelectric conversion module is as follows:
the photoelectric conversion module arranged in the photoelectric detector is used for converting a light intensity signal of laser light intensity change delta I into a voltage signal so as to measure, and the calculation mode is as follows:
in the formula, δ V is a measured voltage variation amount, and ξ is a displacement light intensity conversion coefficient.
4. The acceleration measurement method based on the anti-maglev mechanics system according to claim 1 or 3, characterized in that: in the fourth step, the calculation method for calculating the actual external acceleration is as follows:
in the formula, a is actual external acceleration, ξ is displacement light intensity conversion coefficient, U (x) is diamagnetic potential energy, δ V is measured voltage variation, and m is diamagnetic mass quality.
5. The acceleration measurement method based on the magnetic levitation resistant mechanical system as claimed in claim 1, wherein: in the second step, before the permanent magnet forms the antimagnetic suspension potential well, the permanent magnet needs to be processed, and the specific implementation mode comprises the following steps:
firstly, processing a permanent magnet by using a numerical control machine tool, and magnetizing the permanent magnet according to a design direction;
secondly, carrying out combined fine adjustment on the permanent magnet;
finally, the permanent magnet is encapsulated by epoxy.
6. The acceleration measurement method based on the anti-maglev mechanics system according to claim 1 or 3, characterized in that: in the third step, before inputting the laser signal to the diamagnetic mass, the position of the optical fiber for transmitting the laser input signal needs to be fixed, and the specific fixing mode is as follows:
firstly, moving the position of the optical fiber to two sides of the diamagnetic mass body through a position operation table for adjustment;
secondly, when the dependence of the light intensity signal and the position of the optical fiber reaches the maximum, the optical fiber is fixed.
7. The acceleration measurement method based on the magnetic levitation resistant mechanical system as claimed in claim 6, wherein: the optical fiber is fixed in the following mode:
fixed thereto by epoxy resin or adhesive, or
It is fixed by a piezoelectric positioning device.
8. The acceleration measurement method based on the magnetic levitation resistant mechanical system as claimed in claim 1, wherein: the diamagnetic mass body is made of a transparent diamagnetic material, wherein the diamagnetic material is graphite or quartz or organic glass PMMA or a diamagnetic high polymer material;
the diamagnetic mass body comprises an upper magnet layer and a lower magnet layer, and the polarization directions of the upper magnet layer and the lower magnet layer are opposite to each other so as to form a stable diamagnetic levitation potential well at the geometric center position of the permanent magnet;
and a through hole is formed in the geometric center direction of the upper magnet layer, so that a diamagnetic restriction area in the horizontal direction is formed.
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114295257A (en) * | 2021-12-29 | 2022-04-08 | 河海大学 | Force sensor based on anti-magnetic suspension principle and measuring method thereof |
| CN114859076A (en) * | 2022-07-06 | 2022-08-05 | 之江实验室 | Acceleration measurement method and device based on optical suspension multi-microsphere array |
| CN115458273A (en) * | 2022-11-09 | 2022-12-09 | 之江实验室 | Double-layer cylindrical permanent magnet anti-magnetic suspension device and preparation and application methods thereof |
Citations (25)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN2089195U (en) * | 1991-04-03 | 1991-11-20 | 南京大学 | Demonstrating apparatus for super conduction suspending locking in magnetic field |
| WO1994010746A1 (en) * | 1992-10-28 | 1994-05-11 | Sri International | Magnetic field levitation |
| WO2004020942A1 (en) * | 2002-09-02 | 2004-03-11 | Ecole Polytechnique Federale De Lausanne (Epfl) | Diamagnetic levitation system |
| US20040244492A1 (en) * | 2003-06-05 | 2004-12-09 | International Business Machines Corporation | Pressure wave sensor using levitated mass |
| US20040244486A1 (en) * | 2003-06-05 | 2004-12-09 | International Business Machines Corporation | Inertial navigation device for ion propulsion driven spacecraft |
| CN1831540A (en) * | 2006-04-20 | 2006-09-13 | 上海交通大学 | Anti-magnetic suspension permanent rotor micro-accelerometer |
| US20100275686A1 (en) * | 2009-04-30 | 2010-11-04 | Bratkovski Alexandre M | Inertial sensing system with a curved base and a diamagnetic mass |
| CN102023309A (en) * | 2010-10-29 | 2011-04-20 | 谭成忠 | Maglev electromagnetic induction cymoscope |
| CN201852944U (en) * | 2010-10-29 | 2011-06-01 | 谭成忠 | Magnetic suspension electromagnetic induction detector |
| US20110273044A1 (en) * | 2010-05-05 | 2011-11-10 | Martin Simon | Large gap horizontal field magnetic levitator |
| WO2012075009A1 (en) * | 2010-11-29 | 2012-06-07 | President And Fellows Of Harvard College | Quality control of diamagnetic materials using magnetic levitation |
| WO2012088119A2 (en) * | 2010-12-20 | 2012-06-28 | President And Fellows Of Harvard College | Three dimensional assembly of diamagnetic materials using magnetic levitation |
| US20150037128A1 (en) * | 2013-08-04 | 2015-02-05 | Gerald Küstler | Monolithic magnets with magnetic field domains for diamagnetic levitation |
| CN106679557A (en) * | 2017-03-17 | 2017-05-17 | 中国农业大学 | Device and measuring method for measuring micrometric displacement of magnetic levitation ball |
| CN106940387A (en) * | 2017-04-10 | 2017-07-11 | 三峡大学 | A kind of Michelson interference formula optical fiber acceleration transducer |
| US20170242050A1 (en) * | 2016-02-18 | 2017-08-24 | China Three Gorges University | High-precision magnetic suspension accelerometer |
| CN109416407A (en) * | 2016-07-26 | 2019-03-01 | 国际商业机器公司 | Parallel dipole line trap seismic detector and vibrating sensor |
| US20190162751A1 (en) * | 2017-11-29 | 2019-05-30 | International Business Machines Corporation | Accelerometer using dimagnetic levitation |
| CN110231664A (en) * | 2019-06-21 | 2019-09-13 | 华中科技大学 | A kind of MEMS inertial sensor to be suspended based on diamagnetic body |
| CN110231663A (en) * | 2019-06-21 | 2019-09-13 | 华中科技大学 | A kind of inertial sensor to be suspended based on diamagnetic body |
| CN110231662A (en) * | 2019-06-21 | 2019-09-13 | 华中科技大学 | A kind of preparation method of the MEMS inertial sensor to be suspended based on diamagnetic body |
| CN111525771A (en) * | 2020-04-02 | 2020-08-11 | 中国科学院电工研究所 | High-acceleration high-stability high-temperature superconducting magnetic levitation vehicle system |
| WO2021006727A1 (en) * | 2019-07-09 | 2021-01-14 | Technische Universiteit Delft | Sensor equipped with at least one magnet and a diamagnetic plate levitating above said at least one magnet and method to measure a parameter of an object using such a sensor |
| US20210025918A1 (en) * | 2019-07-24 | 2021-01-28 | International Business Machines Corporation | Accelerometer based on diamagnetic levitation in a ring magnet |
| WO2021039836A1 (en) * | 2019-08-30 | 2021-03-04 | 泰弘 池添 | Magnetic levitation device and measuring device using same |
-
2021
- 2021-07-05 CN CN202110758876.2A patent/CN113484538B/en active Active
Patent Citations (25)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN2089195U (en) * | 1991-04-03 | 1991-11-20 | 南京大学 | Demonstrating apparatus for super conduction suspending locking in magnetic field |
| WO1994010746A1 (en) * | 1992-10-28 | 1994-05-11 | Sri International | Magnetic field levitation |
| WO2004020942A1 (en) * | 2002-09-02 | 2004-03-11 | Ecole Polytechnique Federale De Lausanne (Epfl) | Diamagnetic levitation system |
| US20040244492A1 (en) * | 2003-06-05 | 2004-12-09 | International Business Machines Corporation | Pressure wave sensor using levitated mass |
| US20040244486A1 (en) * | 2003-06-05 | 2004-12-09 | International Business Machines Corporation | Inertial navigation device for ion propulsion driven spacecraft |
| CN1831540A (en) * | 2006-04-20 | 2006-09-13 | 上海交通大学 | Anti-magnetic suspension permanent rotor micro-accelerometer |
| US20100275686A1 (en) * | 2009-04-30 | 2010-11-04 | Bratkovski Alexandre M | Inertial sensing system with a curved base and a diamagnetic mass |
| US20110273044A1 (en) * | 2010-05-05 | 2011-11-10 | Martin Simon | Large gap horizontal field magnetic levitator |
| CN102023309A (en) * | 2010-10-29 | 2011-04-20 | 谭成忠 | Maglev electromagnetic induction cymoscope |
| CN201852944U (en) * | 2010-10-29 | 2011-06-01 | 谭成忠 | Magnetic suspension electromagnetic induction detector |
| WO2012075009A1 (en) * | 2010-11-29 | 2012-06-07 | President And Fellows Of Harvard College | Quality control of diamagnetic materials using magnetic levitation |
| WO2012088119A2 (en) * | 2010-12-20 | 2012-06-28 | President And Fellows Of Harvard College | Three dimensional assembly of diamagnetic materials using magnetic levitation |
| US20150037128A1 (en) * | 2013-08-04 | 2015-02-05 | Gerald Küstler | Monolithic magnets with magnetic field domains for diamagnetic levitation |
| US20170242050A1 (en) * | 2016-02-18 | 2017-08-24 | China Three Gorges University | High-precision magnetic suspension accelerometer |
| CN109416407A (en) * | 2016-07-26 | 2019-03-01 | 国际商业机器公司 | Parallel dipole line trap seismic detector and vibrating sensor |
| CN106679557A (en) * | 2017-03-17 | 2017-05-17 | 中国农业大学 | Device and measuring method for measuring micrometric displacement of magnetic levitation ball |
| CN106940387A (en) * | 2017-04-10 | 2017-07-11 | 三峡大学 | A kind of Michelson interference formula optical fiber acceleration transducer |
| US20190162751A1 (en) * | 2017-11-29 | 2019-05-30 | International Business Machines Corporation | Accelerometer using dimagnetic levitation |
| CN110231664A (en) * | 2019-06-21 | 2019-09-13 | 华中科技大学 | A kind of MEMS inertial sensor to be suspended based on diamagnetic body |
| CN110231663A (en) * | 2019-06-21 | 2019-09-13 | 华中科技大学 | A kind of inertial sensor to be suspended based on diamagnetic body |
| CN110231662A (en) * | 2019-06-21 | 2019-09-13 | 华中科技大学 | A kind of preparation method of the MEMS inertial sensor to be suspended based on diamagnetic body |
| WO2021006727A1 (en) * | 2019-07-09 | 2021-01-14 | Technische Universiteit Delft | Sensor equipped with at least one magnet and a diamagnetic plate levitating above said at least one magnet and method to measure a parameter of an object using such a sensor |
| US20210025918A1 (en) * | 2019-07-24 | 2021-01-28 | International Business Machines Corporation | Accelerometer based on diamagnetic levitation in a ring magnet |
| WO2021039836A1 (en) * | 2019-08-30 | 2021-03-04 | 泰弘 池添 | Magnetic levitation device and measuring device using same |
| CN111525771A (en) * | 2020-04-02 | 2020-08-11 | 中国科学院电工研究所 | High-acceleration high-stability high-temperature superconducting magnetic levitation vehicle system |
Non-Patent Citations (6)
| Title |
|---|
| CHRISTIAN PIGOT 等: "Optimization of a 3D micro-accelerometer based on diamagnetic levitation", 《HAL》 * |
| FANG XIONG 等: "Searching spin-mass interaction using a diamagnetic levitated magnetic-resonance force sensor", 《PHYSICAL REVIEW》 * |
| YINGCHUN LENG 等: "Mechanical dissipation below 1 Hz with a cryogenic diamagnetic-levitated micro-oscillator", 《PHYSICAL REVIEW》 * |
| 刘博 等: "高速磁浮车用高温超导直线电动机的研究综述", 《低温与超导》 * |
| 徐园平: "抗磁悬浮研究综述", 《机械工程学报》 * |
| 武科迪 等: "抗磁悬浮原理在执行与传感方面的应用研究及发展", 《微纳电子技术》 * |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114295257A (en) * | 2021-12-29 | 2022-04-08 | 河海大学 | Force sensor based on anti-magnetic suspension principle and measuring method thereof |
| CN114295257B (en) * | 2021-12-29 | 2022-09-06 | 河海大学 | Force sensor based on anti-magnetic suspension principle and measuring method thereof |
| CN114859076A (en) * | 2022-07-06 | 2022-08-05 | 之江实验室 | Acceleration measurement method and device based on optical suspension multi-microsphere array |
| CN114859076B (en) * | 2022-07-06 | 2022-10-21 | 之江实验室 | Acceleration measurement method and device based on optical suspension multi-microsphere array |
| CN115458273A (en) * | 2022-11-09 | 2022-12-09 | 之江实验室 | Double-layer cylindrical permanent magnet anti-magnetic suspension device and preparation and application methods thereof |
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