CN115979409A - Angular vibration sensor based on magnetohydrodynamics and angular vibration detection method - Google Patents
Angular vibration sensor based on magnetohydrodynamics and angular vibration detection method Download PDFInfo
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Abstract
The invention provides a magnetohydrodynamics-based angular vibration sensor and an angular vibration detection method. The angular vibration sensor comprises an annular structure, a fluid channel is annular, and conductive fluid is arranged in the fluid channel; the first Halbach array structure is arranged on the periphery of the fluid channel and connected with the fluid channel, and is a structure which is formed by splicing a plurality of annular coaxial first permanent magnets and is provided with a first cavity; the first permanent magnet is configured to generate a first magnetic field in the first cavity; the second Halbach array structure is arranged at the periphery of the first Halbach array structure and is connected with the first Halbach array structure through a supporting structure, and the second Halbach array structure is a structure which is formed by splicing a plurality of annular and coaxial second permanent magnets and is provided with a second cavity; the second permanent magnet is configured to generate a second magnetic field within the second cavity, the magnetic field direction of the first magnetic field and the magnetic field direction of the second magnetic field being opposite.
Description
Technical Field
The invention relates to the technical field of sensor temperature offset, in particular to an angular vibration sensor based on magnetohydrodynamics and an angular vibration detection method.
Background
For a high-precision spacecraft, angular vibration seriously affects the pointing precision, attitude stability and imaging quality of a payload, so that the resolution of an image is greatly reduced. The traditional gyroscope for measuring angular vibration has the disadvantages of narrow frequency band, low precision, contact abrasion and the like of a dynamically tuned gyroscope, the laser gyroscope is expensive and has locking problems, the precision of the fiber optic gyroscope is restricted by the product, and the MEMS gyroscope is suitable for low-frequency measurement and has larger noise and the like. The emerging Magnetic Hydrodynamics (MHD) based angular vibration sensor measures angular vibration information by detecting output potential between electrodes, meets the technical requirements of kilohertz bandwidth and sub-radian precision of on-orbit satellite angular vibration measurement, and is more suitable for the technical field of high-precision space by virtue of the characteristics of high reliability, long service life, high measurement precision, low power consumption, easiness in miniaturization and the like.
The MHD angular vibration sensor is arranged on a high-precision spacecraft when angular vibration is measured in orbit, the working temperature of the MHD angular vibration sensor cannot be guaranteed to be constant due to the interference of the space physical environment, the motion state of fluid and the magnetic induction intensity in a fluid channel are changed due to the change of the external temperature, the output potential of the angular vibration sensor based on magnetohydrodynamics is changed, the scale factor of the sensor is shifted, and the measuring precision and the reliability of the sensor are greatly influenced.
Disclosure of Invention
In view of this, the embodiment of the present invention provides a magnetohydrodynamics-based angular vibration sensor and an angular vibration detection method.
One aspect of an embodiment of the present invention provides a magnetohydrodynamics-based angular vibration sensor, including: a ring-shaped structure. The annular structure includes a fluid channel, a first halbach array structure, and a second halbach array structure. The fluid channel is annular, and conductive fluid is arranged in the fluid channel. The first Halbach array structure is arranged on the periphery of the fluid channel and connected with the fluid channel, and is a structure which is formed by splicing a plurality of annular coaxial first permanent magnets and is provided with a first cavity; the first permanent magnet is configured to generate a first magnetic field in the first cavity. The second Halbach array structure is arranged on the periphery of the first Halbach array structure and is connected with the first Halbach array structure through a supporting structure, the second Halbach array structure is a structure which is formed by splicing a plurality of annular and coaxial second permanent magnets and is provided with a second cavity, the second permanent magnets are configured to generate a second magnetic field in the second cavity, and the direction of the first magnetic field is opposite to that of the second magnetic field.
The unevenness of the first magnetic field is less than 10%, the unevenness of the second magnetic field is less than 10%, and under the condition that the temperature changes, the variation of the first magnetic field in the fluid channel is the same as that of the second magnetic field in the fluid channel; under the condition that the detected target generates angular vibration, the conductive fluid and the annular structure rotate relatively, so that the conductive fluid generates induced electromotive force under the action of the first magnetic field and the second magnetic field, and the angular vibration is obtained according to the induced electromotive force.
According to an embodiment of the present invention, the first permanent magnet and the second permanent magnet satisfy the following condition:
wherein ,
represents the average magnetic induction, which is generated by the second permanent magnet at the initial temperature, in the fluid channel>
Represents the average magnetic induction, which is generated by the first permanent magnet in the fluid channel at the initial temperature, is->
Represents the temperature coefficient of remanence of the second permanent magnet->
Represents a temperature coefficient of remanence of the first permanent magnet,
represents a first magnetic temperature coefficient of the first permanent magnet representing a change in magnetic field resulting from a change in thermal expansion dimension of the first permanent magnet, and->
A second magnetic temperature coefficient of the second permanent magnet is represented, the second magnetic temperature coefficient representing a change in the magnetic field due to a change in a thermal expansion dimension of the second permanent magnet.
Optionally, the ring structure further comprises: a first electrode disposed at a top of the fluid channel and a second electrode disposed at a bottom of the fluid channel, the first and second electrodes adapted to transfer an induced electromotive force.
Optionally, the magnetohydrodynamic based angular vibration sensor further comprises a housing. An accommodating space is formed inside the shell, and the annular structure is located in the accommodating space and connected with the shell.
Optionally, the magnetohydrodynamics-based angular vibration sensor further comprises a stem disposed in the receiving space, the stem being connected to the housing. Wherein, loop configuration encircles the stem setting, and the stem is applicable to and rotates around the center pin of stem under the condition that detects angular vibration, and then drives loop configuration and rotates.
Optionally, the first permanent magnet has a remanence temperature coefficient greater than the remanence temperature coefficient of the second permanent magnet.
Optionally, the number of the first permanent magnets is eight, the cross section of the first halbach array structure in the height direction is a first octagonal ring, the outer ring of the first octagonal ring is a first regular octagon, the radius of a circumscribed circle of the first regular octagon ring is 4-5mm, the inner ring of the first octagonal ring is a second regular octagon, and the radius of a circumscribed circle of the second regular octagon ring is 3.5-4.5mm. The number of the second permanent magnets is eight, the section of the second Halbach array structure in the height direction is a second octagonal ring, the outer ring of the second octagonal ring is a third regular octagon, the radius of the external circle of the third regular octagon is 8.3mm, the inner ring of the second octagonal ring is a fourth regular octagon, and the radius of the external circle of the fourth regular octagon is 5.5mm.
Optionally, the first permanent magnet is made of neodymium iron boron, and the second permanent magnet is made of cobalt.
Optionally, the size of the first halbach array structure and the size of the second halbach array structure are obtained through simulation after modeling by electromagnetic field analysis software.
Another embodiment of the present invention provides an angular vibration detection method using any one of the above angular vibration sensors, including: generating a first magnetic field within a first cavity in a first halbach array structure of the ring structure; generating a second magnetic field with the magnetic field direction opposite to the first magnetic field direction in a second cavity in a second Halbach array structure of the annular structure, wherein the variation of the first magnetic field is the same as that of the second magnetic field under the condition of temperature variation; under the condition that the detection target generates angular vibration, the conductive fluid rotates relative to the annular structure, the conductive fluid generates induced electromotive force under the action of the first magnetic field and the second magnetic field, and the angular vibration is obtained according to the induced electromotive force.
The invention provides a magnetohydrodynamics-based angular vibration sensor, which starts from a magnetic circuit structure of a permanent magnet, utilizes a Halbach annular array structure composed of different permanent magnet materials to sleeve a first Halbach array structure and a second Halbach array structure which are combined on the outer ring of a magnetohydrodynamics-based angular vibration sensor fluid channel, generates a first magnetic field and a second magnetic field in opposite directions in the fluid channel, provides a radial and high-uniformity magnetic field for fluid in the magnetohydrodynamics-based angular vibration sensor, forms a high-temperature stable magnetic field in an inner ring magnetic field composed of the first Halbach array structure, and further reduces the influence of temperature on the output potential of the magnetohydrodynamics-based angular vibration sensor.
Drawings
FIG. 1 shows a cross-sectional view of a prior art magnetohydrodynamic-based angular vibration sensor;
FIG. 2 shows a magnetic field strength plot for an angular vibration sensor of the prior art magnetohydrodynamic-based angular vibration sensor of FIG. 1;
FIG. 3 shows a cross-sectional view of a magnetohydrodynamic-based angular vibration sensor in accordance with an embodiment of the present invention;
FIG. 4 shows a cross-sectional view of an annular structure of a magnetohydrodynamic-based angular vibration sensor of an embodiment of the present invention;
FIG. 5 shows a magnetic field profile of a Halbach array linear array;
FIG. 6 shows a magnetic field profile of a Halbach array annular array;
fig. 7 shows the magnetic field pattern of an annular halbach array composed of eight permanent magnets with octagonal rings in section in the height direction;
FIG. 8 illustrates the total magnetic field strength in the fluid channel of the magnetohydrodynamic-based angular vibration sensor of FIG. 4;
FIG. 9 is a graph of the average magnetic induction produced in the fluid passage by the modified magnetic circuit and the primary magnetic circuit of FIG. 4 as a function of temperature;
FIG. 10 is a graph showing the average magnetic induction density produced by the second Halbach array structure of FIG. 4 as a function of the radius of the circumscribed circle of the third regular octagon, the fourth regular octagon;
fig. 11 is a graph showing the relationship between the unevenness of the magnetic field generated by the second halbach array structure shown in fig. 4 and the radius of the circumscribed circle of the third regular octagon and the fourth regular octagon;
FIG. 12 is a graph showing the variation of average magnetic induction before and after thermal expansion of the first Halbach array structure of FIG. 4 as a function of the radius of the circumscribed circle of the first regular octagon and the second regular octagon;
FIG. 13 illustrates the average magnetic induction produced by the first Halbach array structure as a function of the radius of the circumscribed circle of the first regular octagon, the second regular octagon;
fig. 14 shows the relationship between the magnetic field unevenness and the radius of the circumscribed circle of the first and second regular octagons in the first halbach array structure.
Description of the reference numerals:
1-a ring-shaped structure;
11-a fluid channel;
12-a first halbach array structure;
121-a first permanent magnet;
13-a second halbach array structure;
131-a second permanent magnet;
14-a first electrode;
15-a second electrode;
16-a first cavity;
17-a second cavity;
2-a housing;
3-core column;
4-existing MHD angular vibration sensors;
41-permanent magnet; 42-a fluid channel; 43-stem.
Detailed Description
Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. It is to be understood that such description is merely illustrative and not intended to limit the scope of the present invention. In the following detailed description, for purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of the embodiments of the invention. It may be evident, however, that one or more embodiments may be practiced without these specific details. Moreover, in the following description, descriptions of well-known structures and techniques are omitted so as to not unnecessarily obscure the concepts of the present invention.
The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The terms "comprises," "comprising," and the like, as used herein, specify the presence of stated features, steps, operations, and/or components, but do not preclude the presence or addition of one or more other features, steps, operations, or components.
All terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art unless otherwise defined. It is noted that the terms used herein should be interpreted as having a meaning that is consistent with the context of this specification and should not be interpreted in an idealized or overly formal sense.
Where a convention analogous to "A, B and at least one of C, etc." is used, in general such a construction is intended in the sense one having skill in the art would understand the convention (e.g., "a system having at least one of A, B and C" would include, but not be limited to, systems that have a alone, B alone, C alone, a and B together, a and C together, B and C together, and/or A, B, C together, etc.).
Fig. 1 shows a cross-sectional view of a prior art magnetohydrodynamic based angular vibration sensor.
As shown in fig. 1, the conventional MHD angular vibration sensor 4 includes a permanent magnet 41, a fluid passage 42, and a stem 43. The stem 43 is disposed at a central position based on the existing MHD angular vibration sensor 4, fixedly surrounds the stem 43 in the z-axis direction (i.e., height direction), and the fluid passage 42 is provided with a conductive fluid. When the detection target is subjected to angular vibration, the stem 43 rotates about the central axis in the z-axis direction thereof, and the permanent magnet 41 rotates. The conductive fluid in the fluid channel 42 and the permanent magnet 41 rotate relatively, so that the conductive fluid generates an induced electromotive force under the action of the magnetic field generated by the permanent magnet 41.
Fig. 2 shows a magnetic field strength diagram of an angular vibration sensor of the prior art magnetohydrodynamic-based angular vibration sensor shown in fig. 1.
As shown in FIG. 2, the magnetic induction of the conductive fluid in the fluid passage 42 is from 3.50X 10 from the end close to the permanent magnet 41 to the end far from the permanent magnet 41 -1 T gradually changes to 1.9X 10 -1 T, gradually decreasing trend. Using a formula for calculating the magnetic field inhomogeneity, i.e.
, wherein ,/>
Represents the unevenness of the magnetic field, and>
representing the maximum value of magnetic induction intensity; />
Representing the minimum value of magnetic induction intensity; />
Represents the average value of the magnetic induction, and the average magnetic induction in the fluid passage 42 is calculated to be 2.70 × 10 -1 T, magnetic field inhomogeneity is 56.34%. As can be seen from fig. 2, the fluid channel 42 of the conventional magnetohydrodynamic angular vibration sensor shown in fig. 1 has a non-uniform magnetic field intensity distribution and a side close to the permanent magnet 41 has the highest magnetic induction intensity. Because the magnetic induction intensity changes with the change of the temperature, the average magnetic induction intensity in the fluid channel 42 in the closed-loop magnetic circuit of the existing MHD angular vibration sensor is greatly influenced by the temperature.
Therefore, the invention starts from the sensitive element permanent magnet of the angular vibration sensor based on magnetohydrodynamics, and achieves high temperature stability by changing the magnetic circuit structure in the angular vibration sensor based on magnetohydrodynamics.
FIG. 3 shows a cross-sectional view of a magnetohydrodynamic-based angular vibration sensor in accordance with an embodiment of the present invention. FIG. 4 shows a cross-sectional view of an annular structure of a magnetohydrodynamic-based angular vibration sensor of an embodiment of the present invention.
As shown in fig. 3 and 4, an embodiment of the present invention provides a magnetohydrodynamics-based angular vibration sensor including: a ring-shaped structure 1. The ring structure 1 comprises a fluid channel 11, a first halbach array structure 12 and a second halbach array structure 13. The fluid channel 11 is annular, and the conductive fluid is provided in the fluid channel 11. The first halbach array structure 12 is disposed at the periphery of the fluid channel 11 and connected to the fluid channel 11, the first halbach array structure 12 is a structure formed by splicing a plurality of annular and coaxial first permanent magnets 121 and having a first cavity 16, and the first permanent magnets 121 are configured to generate a first magnetic field in the first cavity 16. The second halbach array structure 13 is disposed at the periphery of the first halbach array structure 12 and connected to the first halbach array structure 12 through a support structure, the second halbach array structure 13 is a structure formed by splicing a plurality of annular and coaxial second permanent magnets 131 and having a second cavity 17, the second permanent magnets 131 are configured to generate a second magnetic field in the second cavity 17, and the magnetic field direction of the first magnetic field is opposite to the magnetic field direction of the second magnetic field.
Wherein the unevenness of the first magnetic field is less than 10%, the unevenness of the second magnetic field is less than 10%, and when the temperature changes, the variation of the first magnetic field in the fluid passage 11 is the same as the variation of the second magnetic field in the fluid passage 11; under the condition that the detection target generates angular vibration, the conductive fluid and the annular structure 1 rotate relatively, so that the conductive fluid generates induced electromotive force under the action of the first magnetic field and the second magnetic field, and the angular vibration information is obtained according to the induced electromotive force.
According to the embodiment of the invention, the first Halbach array structure and the second Halbach array structure are sequentially sleeved on the periphery of the fluid channel, so that the conductive fluid in the fluid channel can be in a magnetic field with high uniformity, the direction of a first magnetic field generated by the first Halbach array structure is opposite to the direction of a second magnetic field generated by the second Halbach array structure, and under the condition that the temperature changes, the variation of the first magnetic field generated by the first Halbach array structure in the fluid channel is the same as the variation of the second magnetic field generated by the second Halbach array structure, so that the conductive fluid in the fluid channel can be in a magnetic field with high temperature stability, and the temperature has small influence on the output potential of the magnetohydrodynamic angular vibration sensor.
Halbach Array (Halbach Array) is a special permanent magnet structure first proposed by Klaus Halbach, bosch national laboratory, lorens berkeley, usa. The permanent magnets with different magnetizing directions are arranged according to a certain rule, and the required magnetic field is generated through superposition.
Fig. 5 shows the magnetic field profile of a halbach array linear array. Fig. 6 shows the magnetic field profile of a halbach array annular array.
As shown in fig. 5 and 6, the arrows indicate lines of magnetic induction, and the arrow direction indicates the magnetic field direction. Halbach arrays are largely classified by geometry into linear arrays as shown in fig. 5 and circular arrays as shown in a-e in fig. 6. As shown in fig. 5 and 6, a large number of magnetic lines are concentrated on one side of the halbach array structure, and almost no magnetic lines are present on the other side. More magnetic lines of force are gathered at one side of the array, and a uniform magnetic field can be generated in a certain area, so that the distribution characteristic of the magnetic field is better. And the other side has almost no magnetic lines of force, thus having a certain self-shielding function.
According to the embodiment of the present invention, in order to eliminate the influence of the temperature as much as possible, the first halbach array structure 12 and the second halbach array structure 13 satisfy the following condition:
wherein ,
represents the average magnetic induction strength at an initial temperature of the second permanent magnet 131 in the fluid channel 11, and>
represents the average magnetic induction, which is generated in the fluid channel 11 by the first permanent magnet 121 at the initial temperature, is->
Represents the temperature coefficient of remanence of the second permanent magnet 131, is->
Represents the temperature coefficient of remanence of the first permanent magnet 121, < > >>
Represents a first magnetic temperature coefficient of the first permanent magnet 121, which represents a change in the magnetic field due to a change in the thermal expansion dimension of the first permanent magnet 121, and->
A second magnetic temperature coefficient of the second permanent magnet 131, which represents a change in the magnetic field due to a change in the thermal expansion dimension of the second permanent magnet 131.
Specifically, in the formula (1), the minus sign on the right side of the equal sign indicates that the directions of the magnetic fields generated by the first permanent magnet 121 and the second permanent magnet 131 are opposite. The sizes of the first permanent magnet 121 and the second permanent magnet 131 are adjusted within an optional range according to actual requirements by using a magnetic field simulation technology to carry out parameter scanning according to the determination of formula (1)
and />
So that the average magnetic induction and temperature coefficient relationship of the first permanent magnet and the second permanent magnet satisfies the formula (1), thereby canceling the influence of the magnetic field in the fluid passage 11 along with the temperature change.
The combination of at least two permanent magnets made of permanent magnetic material with different temperature coefficients of remanence is arranged in such a way that the proportion of the magnetic field generated by each permanent magnet matches the proportion of the effective temperature coefficient defined by the magnetic and mechanical contributions. Although the temperature coefficients of common permanent magnetic materials are negative, cancellation can be achieved by aligning the magnetic fields generated by each permanent magnet in opposite directions.
According to the embodiment of the present invention, the second permanent magnet 131 is arranged at the spatial position
Temperature dependence of the magnetic field generated at->
As shown in equation (2):
wherein ,
is that the second permanent magnet 131 is in a spatial position->
At the magnetic induction generated at the initial temperature, <' >>
Is the temperature coefficient of remanence of the second permanent magnet 131, < >>
Represents the thermal coefficient associated with the change in the size of the permanent magnet caused by thermal expansion, based on the measured value of the temperature change>
Indicates a changed temperature>
Represents a negligibly high-order term>
For the second permanent magnet 131 to be +in spatial position>
Is at a temperature change>
The magnetic induction intensity generated.
The first permanent magnet 121 has a spatial position of
Temperature dependence of the magnetic field generated at->
As shown in equation (3):
wherein ,
for the first permanent magnet 121 to be->
The magnetic induction intensity generated at the initial temperature,
is the temperature coefficient of remanence of the first permanent magnet 121, is based on>
Represents a thermal coefficient associated with a change in the size of the permanent magnet resulting from thermal expansion>
Indicates a changed temperature>
Represents a negligibly high-order term>
The first permanent magnet 121 is located at a spatial position of
Is at a temperature change>
The magnetic induction generated.
The first permanent magnet 121 and the second permanent magnet 131 are made of different permanent magnet materials. Combining the first permanent magnet 121 and the second permanent magnet 131 such that their respective generated magnetic fields are parallel at each point within the working area, the temperature dependence of the total magnetic field after superposition
As shown in equation (4):
wherein the first item
Represents the contribution of each permanent magnet to the main magnetic field, in which &>
Indicating that the second permanent magnet 131 is in a spatial position->
At the initial temperature, the magnetic induction which is generated is greater or less>
Indicating that the first permanent magnet 121 is in a spatial position->
The magnetic induction intensity generated at the initial temperature; a second item +>
Represents a drift of the magnetic field upon a change in temperature, wherein>
Is the temperature coefficient of remanence of the second permanent magnet 131, < >>
Represents a thermal coefficient associated with a change in the size of the second permanent magnet 131 resulting from thermal expansion, and->
Is the temperature coefficient of remanence of the first permanent magnet 121, is based on>
Represents the thermal coefficient, associated with the change in size of the first permanent magnet 121 resulting from thermal expansion, based on>
Represents a changing temperature; item III
Representing negligible high order terms.
Since the first halbach array structure 12 and the second halbach array structure 13 satisfy formula (1), the equation becomesAfter replacement obtain
Therefore, the second term in equation (4) is equal to 0, which cancels out the drift of the magnetic field when the temperature changes.
According to embodiments of the present invention, the magnetic induction density of the working region using the Halbach annular array structure is reduced by a factor defined by the effective temperature coefficient ratio
. The magnetic induction intensity is directly related to the scale factor index of the magnetohydrodynamic-based angular vibration sensor, so that the remanence temperature coefficient ^ of the first permanent magnet 121 is needed to be greater than or equal to when the temperature is offset based on the formula (1)>
and />
The greater, remanent temperature coefficient of the second permanent magnet 121->
and />
Is small so that the coefficient defined by the effective temperature coefficient ratio->
The smaller the amount of reduction in magnetic induction in the working region (i.e., within the fluid channel). If the uniformity of the first magnetic field or the second magnetic field is poor, it may appear that the formula (1) is only true for a certain point or some points, and the optimal solution value meeting the entire fluid domain cannot be obtained when the dimension of the permanent magnet is determined by parametric magnetic circuit simulation, so that the requirement on the uniformity of the magnetic field generated by the second halbach array structure 13 or the first halbach array structure 12 is high, that is, the non-uniformity of the first magnetic field is required to be less than 10%, the non-uniformity of the second magnetic field is required to be less than 10%, and the magnetic circuit structure composed of the first halbach array structure 12 and the second halbach array structure 13 meets the requirement on the magnetic circuit structure simultaneouslyHigh temperature stability and high magnetic field uniformity.
According to an embodiment of the invention, the ring structure 1 further comprises: a first electrode 14 arranged at the top of the fluid channel 11 and a second electrode 15 arranged at the bottom of the fluid channel 11, the first electrode 14 and the second electrode 15 being adapted to transfer an induced electromotive force.
The working principle of the angular vibration sensor based on magnetohydrodynamics is that moving magnetic flux cuts static conductive fluid by using the speed difference between the conductive fluid and the magnetic induction intensity of an annular structure, so that output potential is generated between a first electrode 14 and a second electrode 15, and the angular vibration information of a moving carrier is judged according to the output potential.
According to the embodiment of the present invention, the first electrode 14 and the second electrode 15 may transmit an electrical signal through the electrode lead lines by providing the through holes through which the electrode lead lines may pass on the first halbach array structure 12 and the second halbach array structure 13.
According to an embodiment of the present invention, as shown in fig. 4, the angular vibration sensor is based on the magnetohydrodynamic effect, and the conductive fluid is filled in the fluid channel 11. The upper and lower wall surfaces of the fluid channel 11, which are in contact with the conductive fluid, are conductive, the inner and outer wall surfaces are insulated, and the fluid channel is placed in a magnetic field environment, and the magnetic field direction is vertical to the core column 3 and is outwards radial. When the stem 3 detects an input angular velocity
In the process, the angular vibration sensor housing is moved at an angular speed with the object to be examined>
The moving magnetic flux cuts the static conductive fluid to respond the rotation of the angular vibration sensor around the core column 3, so that an output potential is generated between the first electrode 14 and the second electrode 15, and the potential between the first electrode 14 and the second electrode 15 is transmitted to a signal amplifying circuit at the later stage in a punching and wire-leading mode.
According to an embodiment of the invention, the magnetohydrodynamic based angular vibration sensor further comprises a housing 2, wherein the ring structure 1 is located in an accommodation space formed inside the housing 2 and is connected to the housing 2.
According to the embodiment of the invention, the shell 2 can play a role in fixing, so that the magnetohydrodynamics-based angular vibration sensor is structurally stable and plays a role in dust prevention.
According to an embodiment of the invention, the magnetohydrodynamically based angular vibration sensor further comprises a stem 3. The core column 3 is arranged in the accommodating space and connected with the shell. Wherein, annular structure 1 encircles the setting of stem 3, and stem 3 is applicable to and rotates around the center pin of stem 3 under the condition that detects angular vibration, and then drives annular structure 1 and rotates. In case of detecting angular vibration, the core column 3 rotates around the central axis, and thus the ring structure 1 rotates, and the moving magnetic flux cuts the stationary conductive fluid, so that an output potential is generated between the first electrode 14 and the second electrode 15.
According to an embodiment of the present invention, due to the repulsive or attractive force generated between the combined array of the first halbach array structure 12 and the second halbach array structure 13, a support structure needs to be provided to enable the combined array to remain stable against relative movement.
According to an embodiment of the invention, the support structure is a non-magnetically conductive material, which may be any one of ceramic, plastic, etc., for example.
According to an embodiment of the present invention, the temperature coefficient of remanence of the first permanent magnet 121 is greater than the temperature coefficient of remanence of the second permanent magnet 131.
According to an embodiment of the present invention, the first permanent magnet 121 may include any one of a neodymium-iron-boron permanent magnet and a ferrite permanent magnet, and the second permanent magnet 131 may include any one of a samarium-cobalt permanent magnet, an alnico permanent magnet, and an iron-chromium-cobalt permanent magnet.
According to the embodiment of the invention, the first permanent magnet is made of neodymium iron boron, and the second permanent magnet is made of cobalt.
According to an embodiment of the present invention, the first permanent magnet 121 may be a neodymium-iron-boron permanent magnet N30SH, and the second permanent magnet 131 may be a samarium-cobalt permanent magnet SmCo32.
According to an embodiment of the present invention, the cross-sections of the first halbach array structure 12 and the second halbach array structure 13 in the height direction may be the same shape having different radii.
According to the embodiment of the present invention, the number of the first permanent magnets 121 may be 16, the cross section of the first halbach array structure 12 along the height direction is a first hexadecimal ring, the outer ring of the first hexadecimal ring is a first regular hexadecimal shape, the inner ring of the first hexadecimal ring is a second regular hexadecimal shape, the cross section of the second halbach array structure 13 along the height direction is a twenty-sixth ring, the outer ring of the twenty-sixth ring is a third regular hexadecimal shape, and the inner ring of the twenty-sixth ring is a fourth regular hexadecimal shape.
As shown in fig. 4, the number of the first permanent magnets may be eight, the cross section of the first halbach array structure in the height direction is a first octagonal ring, the outer ring of the first octagonal ring is a first regular octagon, the range of the radius of the circumscribed circle of the first regular octagon ring is 4-5mm, the inner ring of the first octagonal ring is a second regular octagon, and the range of the radius of the circumscribed circle of the second regular octagon ring is 3.5-4.5mm;
the number of the second permanent magnets can be eight, the cross section of the second Halbach array structure in the height direction is a second octagonal ring, the outer ring of the second octagonal ring is a third regular octagon, the radius of the circumscribed circle of the third regular octagon is 8.3mm, the inner ring of the second octagonal ring is a fourth regular octagon, and the radius of the circumscribed circle of the fourth regular octagon is 5.5mm.
Fig. 7 shows the magnetic field pattern of an annular halbach array composed of eight permanent magnets whose section in the height direction is an octagonal ring.
As shown in fig. 7, the direction of the arrow in the drawing indicates the direction of the magnetic field, which is a relationship between the magnetization direction of each of the permanent magnets constituting the halbach array and the direction of the magnetic field in the halbach array.
FIG. 8 shows the total magnetic field strength in the fluid channel of the magnetohydrodynamic-based angular vibration sensor of FIG. 4.
As shown in fig. 8, from left to right,the magnetic induction of the conductive fluid in the fluid channel 11 is 2.81 × 10 -1 T gradually changes to 2.66X 10 -1 T, tendency to fade, average magnetic induction of 2.735X 10 -1 T, the non-uniformity was 9.33%, which is a 47.02% reduction compared to the existing angular vibration sensor based on magnetohydrodynamics. Therefore, the magnetohydrodynamic angular vibration sensor provided by the invention has high magnetic field uniformity.
Fig. 9 is a graph showing the average magnetic induction generated in the fluid passage by the improved magnetic circuit and the primary magnetic circuit shown in fig. 4 as a function of temperature.
As shown in fig. 9, the abscissa indicates the temperature (deg.c), the left ordinate indicates the variation of the magnetic induction intensity generated in the fluid passage by the modified magnetic circuit (i.e., the magnetic circuit formed by the first halbach array structure 12 and the second halbach array structure 13) under the influence of the temperature, and the right ordinate indicates the variation of the magnetic induction intensity generated in the fluid passage by the primary magnetic circuit (i.e., the magnetic circuit formed by the permanent magnet 41 of the conventional MHD angular vibration sensor) under the influence of the temperature. As can be seen from FIG. 9, the maximum value of the magnetic induction intensity of the improved magnetic circuit in the temperature range of-20 to 60 ℃ is 271.95mT, the minimum value is 271.71mT, and the maximum fluctuation value is about 0.24mTThe curve is in a parabolic shape, and the average magnetic induction temperature coefficient is obtained by linear fitting. The maximum value of the magnetic induction intensity of the original magnetic circuit in the temperature range of-20 to 60 ℃ is about 288mT, the minimum value is about 252mT, the maximum fluctuation value is about 36 mT, and the curve is in a linear shape, so that the improved magnetic circuit formed by the first Halbach array structure 12 and the second Halbach array structure 13 has high temperature stability.
The working principle of the angular vibration sensor based on magnetohydrodynamics is that moving magnetic flux cuts static conductive fluid by utilizing the speed difference between the conductive fluid and magnetic induction intensity so as to respond to the rotation of the sensor around a sensitive shaft to generate output potential between an upper electrode and a lower electrode, thereby judging the angular vibration of a moving carrier. The invention starts with a sensitive element permanent magnet of the angular vibration sensor based on magnetohydrodynamics, and achieves high temperature stability by changing the magnetic circuit structure in the sensor.
According to the embodiment of the invention, starting from the magnetic circuit structure of the permanent magnet, a Halbach annular array structure composed of different permanent magnet materials is utilized, a combined magnetic circuit is formed by a first Halbach array structure 12 and a second Halbach array structure 13 which are combined, and the combined magnetic circuit is sleeved on the outer ring of the fluid channel 11 of the angular vibration sensor based on magnetohydrodynamics, so that the magnetic field direction of a first magnetic field generated by the combined magnetic circuit in the fluid channel 11 is opposite to the magnetic field direction of a second magnetic field, a radial magnetic field with high uniformity is provided for a conductive fluid in the angular vibration sensor based on magnetohydrodynamics, a high-temperature stable magnetic field is formed in the magnetic field of the inner ring composed of the first Halbach array structure 12, and the influence of temperature on the output potential of the angular vibration sensor based on magnetohydrodynamics is further reduced.
According to an embodiment of the invention, the dimensions of the first halbach array structure and the dimensions of the second halbach array structure are simulated after modeling by electromagnetic field analysis software, which may be, for example, ansoft maxwell software.
The dimensions of the second halbach array structure 13 are determined by Ansoft maxwell software modeling, according to an embodiment of the present invention.
Modeling is carried out in Ansoft maxwell software, and a solver selects a two-dimensional static magnetic field in a cylindrical coordinate system. And drawing two regular octagons through a circumscribed circle, and defining the magnetizing direction. The radius of the circumscribed circle of the fourth regular octahedron is expressed asR IIi And the radius of the circumscribed circle of the third regular octahedron is expressed asR IIo 。
A parametric scan of the second halbach array structure 13 model size was performed:R IIi the value is 4 to 7mm, and the step length is 0.5mm;R IIo the value is 5 to 9mm, and the step length is 0.2mm.
Fig. 10 shows the average magnetic induction intensity produced by the second halbach array structure shown in fig. 4 as a function of the radius of the circumscribed circle of the third and fourth regular octagons.
The second Halbach array structure in FIG. 4 isAnd a second octagonal ring which is composed of eight second permanent magnets and has a cross section in the height direction. The outer ring of the second octagonal ring is a third regular octagon, and the inner ring of the second octagonal ring is a fourth regular octagon. In fig. 10, the abscissa indicates the circumscribed radius (mm) of the third regular octagon, and the ordinate indicates the average magnetic induction (T) at the circumscribed radius (mm) of the third regular octagon of the second halbach array structure 13R IIo When the magnetic induction intensity is not changed, the average magnetic induction intensity follows the radius of a circumscribed circle of the fourth regular octagonR IIi Is increased and decreased, and the radius of the circumscribed circle of the fourth regular octagonR IIi When the magnetic induction intensity is not changed, the average magnetic induction intensity follows the radius of a circumscribed circle of the third regular octagonR IIo Is increased.
Fig. 11 shows the relationship between the unevenness of the magnetic field generated by the second halbach array structure shown in fig. 4 and the radius of the circumscribed circle of the third regular octagon and the fourth regular octagon.
As shown in fig. 11, the abscissa represents the circumscribed circle radius (mm) of the third regular octagon, and the ordinate represents the unevenness (%) of the magnetic field generated by the second halbach array structure. Radius of the third regular octagonR Io When the magnetic field is not changed, the non-uniformity of the magnetic field is along with the radius of the circumscribed circle of the fourth regular octagonR Ii Is increased and decreased, and the radius of the circumscribed circle of the fourth regular octagonR Ii When the magnetic field is not changed, the non-uniformity of the magnetic field follows the radius of the circumscribed circle of the third regular octagonR Io Is increased and decreased.
With reference to fig. 10 and 11, in order to prevent the scale factor of the magnetohydrodynamic-based sensor before and after temperature cancellation from changing, that is, the improved magnetic circuit of the embodiment of the present invention is consistent with the radiation magnetic field generated by the primary magnetic circuit at the conductive fluid, which satisfies the requirement
And the array characteristic determines that the main magnetic flux is positioned at the inner side of the array, and only a small amount of leakage magnetic flux flows out. Combining permanent magnets of formula (1) according to a first halbach array structure and a second halbach array structure without taking into account thermal expansionThe temperature coefficient of remanence and the radiation magnetic field generated by the first halbach array structure and the second halbach array structure at the conductive fluid are consistent with the radiation magnetic field generated by the primary magnetic circuit at the conductive fluid and are 0.27T, so that the magnetic field generated by the second halbach array structure 13 in the improved magnetic circuit at the conductive fluid is about 0.37T through calculation. As can be seen from FIG. 11, the size set satisfying a magnetic field of about 0.37T is 4,5.9]，[4.5，6.7]，[5，7.5]And [5.5,8.3]，([A，B]To representAIs composed ofR IIi ，BIs composed ofR IIo ). In practical engineering application, under the condition that the unevenness of the magnetic field is less than 10%, the magnetic field is considered to be a uniform magnetic field, and the size set meets the uniformity requirement. The second halbach array structure 13 is dimensioned to allow space for the first halbach array structure 12 in view of the first halbach array structure 12 being located inside the second halbach array structure 13R IIi =5.5mm，R IIo =8.3mm。
Having determined the dimensions of the second halbach array structure 13, further determinations are needed
The magnetic field generated by the first halbach array structure 12 can be precisely calculated to eliminate the effects of temperature variations. Considering thermal expansion deformation of the array towards the center, temperature change is 1 deg.CR IIi AndR IIo respectively is->
、
. The second Halbach array structure 13 model after deformation is simulated, and the change of the average magnetic induction intensity of the conductive fluid is-0.8 multiplied by 10 -6 T, i.e>
=-0.8ppm/℃。
First Halbach array Structure 12 as a cancellation arrayIs smaller than the second halbach array structure 13. The first halbach array structure 12 is composed of eight cobalt permanent magnets, and the magnetizing direction is opposite to that of the second halbach array structure 13, so that a magnetic field which is in reverse parallel to the second halbach array structure 13 can be generated in a ring to play a role in offsetting. According to the formula (1), the magnetic field generated by the first Halbach array at the conductive fluid needs to be solved
And/or>
Closely related to the structural dimensions of the first halbach array structure 12. Therefore, the change of the average magnetic induction intensity of the conductive fluid before and after the first halbach array structure 12 is subjected to thermal expansion when the temperature changes by 1 ℃ is solved through parametric scanning and different model sizes.
The radius of the circumscribed circle of the second regular octagon is expressed asR Ii The radius of the circumscribed circle of the first regular octagon is expressed asR IIo . Since the first halbach array structure 12 and the second halbach array structure 13 cannot be in direct contact, which would otherwise destroy the respective generated magnetic field, there is a space between the arrays for mounting the support material. Therefore, it is not only easy to useR Ii The value is 3.5 to 4.5mm, and the step length is 0.2mm;R Io the value is 4 to 5mm, and the step length is 0.2mm.
Fig. 12 shows the relationship between the change in average magnetic induction intensity before and after thermal expansion of the first halbach array structure shown in fig. 4 and the radius of the circumscribed circle of the first regular octagon and the second regular octagon.
As shown in fig. 12, the abscissa is the radius of the circumscribed circle of the first regular octagonR Io (mm), the ordinate represents the change in average magnetic induction before and after thermal expansion (× 10) -6 T). As shown in fig. 3, the amount of change in the average magnetic induction before and after thermal expansion is positive or negative, which is because when the first halbach array structure 12 is thermally expanded, on the one hand, the radiuses of the circumscribed circles of the first regular octagon and the second regular octagon are all equalOutward expansion, i.e., the first halbach array structure 12 being farther from the conductive fluid, will result in a reduced magnetic induction; on the other hand, the length scale of the expansion of the circumscribed circle of the first regular octagon is larger, so that the radius difference is increased, that is, the thickness direction size of each permanent magnet of the first halbach array structure 12 is increased, so that the magnetic induction intensity is enhanced.
Fig. 13 shows the average magnetic induction intensity produced by the first halbach array structure as a function of the radius of the circumscribed circle of the first regular octagon, the second regular octagon.
As shown in FIG. 13, the abscissa represents the radius of the circumscribed circle of the first regular octagonR Io (mm), the ordinate represents the average magnetic induction (T). Radius of circumscribed circle of the first regular octagonR Io When the magnetic induction intensity is not changed, the average magnetic induction intensity follows the radius of the circumscribed circle of the second regular octagonR Ii Is increased and decreased, and the radius of the circumscribed circle of the second regular octagon is increased and decreasedR Ii When the magnetic induction intensity is not changed, the average magnetic induction intensity follows the radius of the circumscribed circle of the first regular octagonR Io Is increased and decreased.
Fig. 14 shows the relationship between the magnetic field unevenness and the radius of the circumscribed circle of the first regular octagon and the second regular octagon in the first halbach array structure.
As shown in FIG. 14, the abscissa represents the radius of the first regular octagon circumscribed by the first Halbach array structure 12R Io (mm), and the ordinate represents the magnetic field unevenness (%). The radius of the outer octagon circumscribing the first halbach array structure 12R Io When the magnetic field is not changed, the unevenness of the magnetic field follows the radius of the circumscribed circle of the second regular octagonR IIi Is increased and decreased, and the radius of the circle circumscribed by the second regular octagonR Ii When the magnetic field is not changed, the unevenness of the magnetic field follows the radius of the circumscribed circle of the first regular octagonR Io Is increased and decreased.
In connection with fig. 13-14, the magnetic field generated by the first halbach array structure 12 at the conductive fluid is-0.1T, calculated according to equation (1), without taking into account dimensional changes. Similarly, the first halbach array structure 12 can be dimensioned by parametric scanning to obtain the average magnetic induction and magnetic field non-uniformity of the conductive fluid as shown in fig. 13 and 14, respectivelyR Ii 、R Io The relationship of (1).
As judged from FIG. 13, the set of dimensions that satisfies a magnetic field of about-0.1T is [3.7,4.1 ]]，[3.9，4.3]，[4.1，4.6]，[4.3，4.8]And [4.5,5.0]，（[C，D]To representCIs composed ofR Ii ，DIs composed ofR Io ). In view of the requirement of uniform magnetic field (magnetic field with non-uniformity of less than 10%), in conjunction with FIG. 14, it can be judged that [4.3,4.8%]And [4.5,5.0]It is satisfied that the first halbach array structure 12 is sized to have a space for installing the supporting material between the first halbach array structure 12 and the second halbach array structure 13R Ii =4.3mm，R Io =4.8mm. Substituting the dimensions into FIG. 11 for verification
Satisfying the formula (1). />
In summary, the structure size based on the combined halbach array magnetic circuit is determined, and the second halbach array structure 13 has the size ofR IIi =5.5mm，R IIo =8.3mm; the first Halbach array structure 12 has a size ofR Ii =4.3mm，R Io =4.8mm。
Another embodiment of the present invention provides an angular vibration detection method using any one of the above angular vibration sensors, including: generating a first magnetic field within a first cavity in a first halbach array structure 12 of the ring structure 1; generating a second magnetic field with a magnetic field direction opposite to the first magnetic field direction in a second cavity in the second halbach array structure 13 of the ring structure 1, wherein the change amount of the first magnetic field is the same as that of the second magnetic field under the condition of temperature change; under the condition that the detection target generates angular vibration, the conductive fluid rotates relative to the annular structure 1, the conductive fluid generates induced electromotive force under the action of the first magnetic field and the second magnetic field, and the angular vibration information is obtained according to the induced electromotive force.
The use of ordinal numbers such as "first," "second," "third," etc., in the specification and claims to modify a corresponding element does not by itself connote any ordinal number of the element or any ordering of one element from another or the order of manufacture, and the use of the ordinal numbers is only used to distinguish one element having a certain name from another element having a same name.
The above-mentioned embodiments are intended to illustrate the objects, technical solutions and advantages of the present invention in further detail, and it should be understood that the above-mentioned embodiments are only exemplary embodiments of the present invention and are not intended to limit the present invention, and any modifications, equivalents, improvements and the like made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (10)
1. A magnetohydrodynamics-based angular vibration sensor, comprising:
a ring structure comprising:
the fluid channel is annular, and conductive fluid is arranged in the fluid channel;
the first Halbach array structure is arranged on the periphery of the fluid channel and connected with the fluid channel, and is a structure which is formed by splicing a plurality of annular and coaxial first permanent magnets and is provided with a first cavity; the first permanent magnet is configured to generate a first magnetic field in the first cavity;
the second Halbach array structure is arranged at the periphery of the first Halbach array structure and is connected with the first Halbach array structure through a supporting structure, and the second Halbach array structure is a structure which is formed by splicing a plurality of annular coaxial second permanent magnets and is provided with a second cavity; the second permanent magnet is configured to generate a second magnetic field within the second cavity, the magnetic field direction of the first magnetic field and the magnetic field direction of the second magnetic field being opposite;
wherein the first magnetic field has a non-uniformity of less than 10% and the second magnetic field has a non-uniformity of less than 10%, and the amount of change in the first magnetic field in the fluid channel is the same as the amount of change in the second magnetic field in the fluid channel when the temperature changes; under the condition that the detected target generates angular vibration, the conductive fluid and the annular structure rotate relatively, so that the conductive fluid generates induced electromotive force under the action of the first magnetic field and the second magnetic field, and the angular vibration is obtained according to the induced electromotive force.
2. The angular vibration sensor according to claim 1, wherein the first permanent magnet and the second permanent magnet satisfy the following condition:
wherein ,
represents the average magnetic induction, which is generated by the second permanent magnet at the initial temperature, in the fluid channel>
Represents the average magnetic induction that is generated by the first permanent magnet in the fluid channel at an initial temperature, and +>
Represents the temperature coefficient of remanence of the second permanent magnet->
Represents the temperature coefficient of remanence of the first permanent magnet->
Represents a first magnetic temperature coefficient of the first permanent magnet that represents a change in magnetic field due to a change in a thermal expansion dimension of the first permanent magnet, and->
A second magnetic temperature coefficient of the second permanent magnet is represented, the second magnetic temperature coefficient representing a change in the magnetic field due to a change in a thermal expansion dimension of the second permanent magnet.
3. The angular vibration sensor of claim 1, wherein the annular structure further comprises:
a first electrode disposed at a top of the fluid channel and a second electrode disposed at a bottom of the fluid channel, the first and second electrodes adapted to transfer the induced electromotive force.
4. The angular vibration sensor according to claim 1, further comprising:
the shell, the inside of the said shell forms a space;
wherein, the annular structure is located in the accommodation space, and is connected with the shell.
5. The angular vibration sensor of claim 4, further comprising:
the core column is arranged in the accommodating space and is connected with the shell;
wherein, the loop configuration encircles the stem setting, the stem is applicable to detecting around under the condition of angular vibration the center pin of stem rotates, and then drives the loop configuration rotates.
6. The angular vibration sensor of claim 1, wherein a temperature coefficient of remanence of the first permanent magnet is greater than a temperature coefficient of remanence of the second permanent magnet.
7. The angular vibration sensor according to claim 1, wherein the number of the first permanent magnets is eight, the cross section of the first halbach array structure in the height direction is a first octagonal ring, the outer ring of the first octagonal ring is a first regular octagon, the radius of the circumscribed circle of the first regular octagon ring is in the range of 4 to 5mm, the inner ring of the first octagonal ring is a second regular octagon, and the radius of the circumscribed circle of the second regular octagon ring is in the range of 3.5 to 4.5mm;
the number of the second permanent magnets is eight, the cross section of the second Halbach array structure along the height direction is a second octagonal ring, the outer ring of the second octagonal ring is a third regular octagon, the external circle radius of the third regular octagon is 8.3mm, the inner ring of the second octagonal ring is a fourth regular octagon, and the external circle radius of the fourth regular octagon is 5.5mm.
8. The angular vibration sensor of claim 1, wherein the material of the first permanent magnet is neodymium iron boron and the material of the second permanent magnet is cobalt fir.
9. The angular vibration sensor of claim 1, wherein the dimensions of the first halbach array structure and the dimensions of the second halbach array structure are simulated after modeling by electromagnetic field analysis software.
10. A method of detecting angular vibration using the angular vibration sensor according to any one of claims 1 to 9, comprising:
generating a first magnetic field within the first cavity in the first Halbach array structure of the ring structure;
generating a second magnetic field with a magnetic field direction opposite to the first magnetic field direction in a second cavity in a second Halbach array structure of the ring structure, wherein under the condition of temperature change, the change amount of the first magnetic field is the same as that of the second magnetic field;
under the condition that the detected target generates angular vibration, the conductive fluid relatively rotates relative to the annular structure, the conductive fluid generates induced electromotive force under the action of the first magnetic field and the second magnetic field, and the angular vibration is obtained according to the induced electromotive force.
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
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Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| SU1752446A1 (en) * | 1990-01-18 | 1992-08-07 | Казанский Авиационный Институт Им.А.Н.Туполева | Angular oscillations test facility |
| CN103453896A (en) * | 2013-09-13 | 2013-12-18 | 天津大学 | Magnetic-fluid gyroscope |
| WO2014161044A1 (en) * | 2013-04-05 | 2014-10-09 | Woodside Energy Technologies Pty Ltd | Method and system of multi-source marine seismic surveying |
| CN107655464A (en) * | 2017-11-07 | 2018-02-02 | 珠海磐磊智能科技有限公司 | Gyroscope and its control method |
| CN114252821A (en) * | 2020-09-23 | 2022-03-29 | 布鲁克碧奥斯平Mri有限公司 | Magnet arrangement, device comprising the same and method for generating a selection field |
| CN114370930A (en) * | 2020-10-15 | 2022-04-19 | 天津大学 | Method for measuring satellite structure micro-angle vibration by using MHD micro-angle vibration sensor |
| US20230057613A1 (en) * | 2021-08-18 | 2023-02-23 | Honeywell International Inc. | Rotation measurement system using coriolis and euler forces |
| CN115824381A (en) * | 2022-11-28 | 2023-03-21 | 合肥工业大学 | Line vibration sensor with magnetohydrodynamic pump |
-
2023
- 2023-03-22 CN CN202310279083.1A patent/CN115979409B/en active Active
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| SU1752446A1 (en) * | 1990-01-18 | 1992-08-07 | Казанский Авиационный Институт Им.А.Н.Туполева | Angular oscillations test facility |
| WO2014161044A1 (en) * | 2013-04-05 | 2014-10-09 | Woodside Energy Technologies Pty Ltd | Method and system of multi-source marine seismic surveying |
| CN103453896A (en) * | 2013-09-13 | 2013-12-18 | 天津大学 | Magnetic-fluid gyroscope |
| CN107655464A (en) * | 2017-11-07 | 2018-02-02 | 珠海磐磊智能科技有限公司 | Gyroscope and its control method |
| CN114252821A (en) * | 2020-09-23 | 2022-03-29 | 布鲁克碧奥斯平Mri有限公司 | Magnet arrangement, device comprising the same and method for generating a selection field |
| CN114370930A (en) * | 2020-10-15 | 2022-04-19 | 天津大学 | Method for measuring satellite structure micro-angle vibration by using MHD micro-angle vibration sensor |
| US20230057613A1 (en) * | 2021-08-18 | 2023-02-23 | Honeywell International Inc. | Rotation measurement system using coriolis and euler forces |
| CN115824381A (en) * | 2022-11-28 | 2023-03-21 | 合肥工业大学 | Line vibration sensor with magnetohydrodynamic pump |
Non-Patent Citations (3)
| Title |
|---|
| WANG K等: "Design parameters analysis and verification of angular vibration sensor based on magnetohydrodynamics", INTERNATIONAL JOURNAL OF METROLOGY AND QUALITY ENGINEERING, vol. 12, no. 2, pages 1 - 7 * |
| XIA G等: "Research on Characteristics of Magnetohydrodynamic Micro-Angle Vibration Sensor in AC Magnetic Field", IEEE SENSORS JOURNAL, vol. 23, no. 6, pages 5650 - 5659 * |
| 吴建铭: "基于磁流体动力学效应的角随机颤振传感器技术研究", 中国优秀硕士学位论文全文数据库 信息科技辑, no. 9, pages 1 - 80 * |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN118091257A (en) * | 2024-04-26 | 2024-05-28 | 天津大学 | System and method for measuring sensitive loop resistance of magnetic fluid angular vibration sensor |
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