CN106969750A - Magnetic liquid omniazimuthal horizontal obliquity sensor - Google Patents
Magnetic liquid omniazimuthal horizontal obliquity sensor Download PDFInfo
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- CN106969750A CN106969750A CN201710321011.3A CN201710321011A CN106969750A CN 106969750 A CN106969750 A CN 106969750A CN 201710321011 A CN201710321011 A CN 201710321011A CN 106969750 A CN106969750 A CN 106969750A
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01C—MEASURING DISTANCES, LEVELS OR BEARINGS; SURVEYING; NAVIGATION; GYROSCOPIC INSTRUMENTS; PHOTOGRAMMETRY OR VIDEOGRAMMETRY
- G01C9/00—Measuring inclination, e.g. by clinometers, by levels
- G01C9/18—Measuring inclination, e.g. by clinometers, by levels by using liquids
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01C—MEASURING DISTANCES, LEVELS OR BEARINGS; SURVEYING; NAVIGATION; GYROSCOPIC INSTRUMENTS; PHOTOGRAMMETRY OR VIDEOGRAMMETRY
- G01C9/00—Measuring inclination, e.g. by clinometers, by levels
- G01C9/18—Measuring inclination, e.g. by clinometers, by levels by using liquids
- G01C2009/187—Measuring inclination, e.g. by clinometers, by levels by using liquids magnetic, e.g. ferromagnetic
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- Measurement Of Length, Angles, Or The Like Using Electric Or Magnetic Means (AREA)
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Abstract
The present invention is a kind of magnetic liquid omniazimuthal horizontal obliquity sensor, and the sensor includes magnetic liquid measuring cell, support, horizontal base and stack permanent magnet；The magnetic liquid measuring cell includes closing spherical shell, three tunnel magneto resistance (TMR) sensors, connecting rod, connection ring and magnetic liquid；Spherical shell is closed built with the magnetic liquid and stack permanent magnet for accounting for spherical shell volume 40%~50%, and is connected by connecting rod with connection ring.Sensor of the invention by the design of stack permanent magnet, solve with tilt angle varied magnetic induction density B rate of change it is uneven the problem of, considerably improve the measurement accuracy of sensor and the stability of sensor.The sensor is by the design of compass on horizontal base, and the problem of solving the object of reference of yawing moment adds the normalization of yawing moment angle measurement.
Description
Technical field
The present invention relates to a kind of obliquity sensor, a kind of obliquity sensor of use magnetic liquid is related generally to.
Background technology
With the continuous progress of science and technology, usually need accurately to measure working face relative to level in social production practice
The angle of inclination in face, such as high-precision laser instrument leveling, engineering machinery leveling, dam monitoring, the launch angle of satellite missile,
Aircraft flight posture etc., therefore obliquity sensor has quite varied application prospect.The inclination angle industrially applied at present is passed
Sensor can be divided into " solid pendulum ", " liquid pendulum ", three kinds of " Liquid Pendulum ".Compared to " solid pendulum " and；" liquid pendulum " formula inclination angle is passed
Sensor, " Liquid Pendulum " formula obliquity sensor is easily disturbed by factors, therefore the property of " Liquid Pendulum " formula obliquity sensor
Stabilizability is poor, practical application rate is low.Compared to " liquid pendulum " formula obliquity sensor, " solid pendulum " obliquity sensor exist machinery
The problem of delayed and abrasion.
A kind of existing magnetic liquid sensor, it has a glass tube, and glass tube holds filled with non magnetic carrier fluid peace treaty half
The magnetic liquid of body product, the outer radial periphery of glass tube is wrapped excitation coil, difference induction coil.Excitation coil produces magnetic
, the magnetic liquid in magnetizing tube, when glass tube is tilted, magnetic liquid is moved under gravity, the winding of its periphery
Difference induction coil produces induced-current.The electric current is the function at sensor perturbations angle.Because this kind of obliquity sensor is merely able to
Measuring measurement three-dimensional space slope angle in the inclination angle of a certain fixed-direction, actual use needs at least two to be mutually perpendicular to place
Obliquity sensor can just realize the measurement at three dimensions introversion oblique angle, the obliquity sensor can not realize synchro measure tilt
Angle and deflection angle；Due to the limitation of this kind of sensor this body structure, magnetic liquid increases with inclination angle in obliquity sensor pipe
Movement under gravity is less and less, so the measurement accuracy of obliquity sensor can be reduced with the increase at inclination angle, should
Obliquity sensor can not realize the measurement of ± 180 ° of full angles；Because this kind of sensor needs to produce magnetic field by excitation coil,
So needing to be equipped with corresponding excitation power supply using the obliquity sensor, the use difficulty and cost of obliquity sensor are added,
Realize that dip angle signal, to the conversion of electric signal, adds the volume and weight of sensor, is not easy to by difference induction coil
Used in existing system.
The content of the invention
For deficiency present in current techniques, the purpose of the present invention is a kind of interior ± 180 ° suitable for three dimensions to provide
Full angle, the obliquity sensor of multi-faceted measurement.The sensor solves existing magnetic by the design of magnetic liquid measuring cell
Property liquid sensor measurement direction fixed single, the problems such as measurement range is narrow, the sensor can be with synchro measure three dimensions
Inclination angle and deflection angle and measurement range expands to ± 180 °, significantly improve the applicability and operating efficiency of measuring system.
The sensor is solved and asked with tilt angle varied magnetic induction density B rate of change is uneven by the design of stack permanent magnet
Topic, considerably improves the measurement accuracy of sensor and the stability of sensor.The sensor passes through guide on horizontal base
The design of pin, the problem of solving the object of reference of yawing moment, adds the normalization of yawing moment angle measurement.
Technical solution of the present invention is：
A kind of magnetic liquid omniazimuthal horizontal obliquity sensor, the sensor includes magnetic liquid measuring cell, support, water
Flat bed and stack permanent magnet；The support is fixed on horizontal base by mounting hole；Magnetic liquid measuring cell is installed
On support；The stack permanent magnet is suspended in the magnetic liquid inside magnetic liquid measuring cell；The horizontal base
It is fixed on by fixing bolt on face to be detected；
The magnetic liquid measuring cell includes closing spherical shell, tunnel magneto resistance (TMR) sensor a, tunnel magneto resistance
(TMR) sensor b, tunnel magneto resistance (TMR) sensor c, connecting rod, connection ring and magnetic liquid；Closing spherical shell is built with accounting for
The magnetic liquid and stack permanent magnet of spherical shell volume 40%~50%, and be connected by connecting rod with connection ring；4 connections
Bar is evenly distributed in closing spherical shell horizontal direction largest circumference, and one end of each connecting rod is vertically fixed on spherical shell；Connection
The other end of bar is connected with connection ring, and circular connection ring is in the outside for closing the largest circumference in the middle part of spherical shell；Tunnel magnetic
Resistance (TMR) sensor b is fixed on the bottommost on the outside of closing spherical shell, tunnel magneto resistance (TMR) sensor a, tunnel magneto resistance
(TMR) sensor c is located at the outside of closing spherical shell horizontal direction largest circumference respectively, and with the centre of sphere on same straight line；
The magnetic liquid is keryl Fe3O4Magnetic liquid, according to volume ratio Fe3O4：Kerosene=8：92 prepare；Four oxygen
Change three-iron is nano particle, and the scope of diameter is in 2~20nm；
Described stack permanent magnet is stacked with the order of radius from small to large by 3-5 blocks cylindrical permanent magnet and constituted, circle
The thickness of post permanent magnet is identical, and the maximum cylinder permanent magnet of diameter is in the top；The cylinder permanent magnet of axial charging is by mutual
Between absorption affinity stack constitute an entirety；The central axis of permanent magnet is overlapped；Described stack permanent magnet is preferably by 5
Block cylindrical permanent magnet stacks composition, and the thickness of five pieces of cylinder permanent magnets is 2mm, radius be followed successively by 10mm, 8mm, 6mm,
4mm、2mm；The radius of described closing spherical shell is 20mm.
Support is four legs, and every leg includes semi-circular pillar, pillar a, adjustable column, pillar b；The semi-circular branch
Post is used for supporting connection ring, and the pillar b is fixed in the corresponding foot mounting aperture of load level base；Pillar a non-threaded end
With being connected for semi-circular pillar, threaded end is connected with adjustable column, and the other end of adjustable column is connected with pillar b threaded ends
Connect.
The horizontal base of magnetic liquid omniazimuthal horizontal obliquity sensor includes four foot mounting apertures, four fixing bolts
Compass is installed in through hole, a compass mounting hole, hole.
Described magnetic liquid omniazimuthal horizontal obliquity sensor also includes A/D analog-digital converters and micro-control processor, often
Individual tunnel magneto resistance (TMR) sensor is connected with an A/D analog-digital converter, three A/D analog-digital converters with micro-control
Device is managed to be connected.
The application process of described magnetic liquid omniazimuthal horizontal obliquity sensor, comprises the following steps：
(1) magnetic liquid omniazimuthal horizontal obliquity sensor is placed, makes tunnel magneto resistance (TMR) sensor of its footDirection north shown in axle measurement direction and compass is consistent, now by fixing bolt by magnetic liquid omniazimuthal horizontal inclination angle
Sensor is fixed on the tested surface for needing to measure inclination angle and deflection angle；
Wherein, centre of sphere O and the connecting line of tunnel magneto resistance (TMR) sensor c 1-4 measurement points are Y-axis, centre of sphere O and tunnel
The connecting line of magneto-resistor (TMR) sensor b 1-3 measurement points is Z axis, the plane that X-axis is constituted perpendicular to Y, Z axis；
(2) zeroing of adjustable column obliquity sensor is rotated：The adjustable column on four legs is rotated, is made at tunnel magneto resistance a, c
In same horizontal line, now tunnel magneto resistance (TMR) sensor a, c are respectiveThree magnetic susceptibility direction of principal axis
On, the outputting measurement value of respective shaft is equal in three axles；Total magnetic induction density B of tunnel magneto resistance (TMR) sensor b measurementsbDeng
In 895.7Gs；Realize that magnetic liquid omniazimuthal horizontal obliquity sensor returns to zero；
Wherein, three tunnel magneto resistances (TMR) sensor is respectively provided withAxle,Axle,Three, axle is orthogonal to be surveyed
Direction is measured, three tunnel magneto resistance (TMR) sensors on spherical shell are fixed onAxle is consistent with X-direction,Axle points to spherical shell
The centre of sphere,Axle perpendicular toAxle,Plane where axle, and in accordance with the right-hand rule；
(3) after tested surface is tilted, 2~3 minutes are stood, treats that obliquity sensor is stable；
(4) tunnel magneto resistance (TMR) sensor output voltage, calculated magnetic induction intensity B are gathereda、Bb、BcSize：Micro-control
Processor STM32 gathers three tunnel magneto resistance (TMR) sensors by A/D analog-digital converter ADS1256, successively, amounts to
Nine road differential output voltage signals；Analog voltage signal is converted to digital voltage signal by analog-digital converter, is forwarded at micro-control
Manage device STM32；Micro-control processor STM32 is by nine digital differential output voltages, according to formula (1) Vx=KBx, calculate respectively
Go out three tunnel magneto resistance (TMR) sensors respectiveThe magnetic induction intensity component B of three axles in directionx、By、
Bz, then recycle formula (2)Calculate tunnel magneto resistance (TMR) sensor a, b,
Magnetic induction density B on three positions of c measurementsa、Bb、Bc；
Wherein, Vx、Bx, K be respectively tunnel magneto resistance (TMR) sensorAxial output voltage, magnetic flux density measurement
Value, sensitivity；Bx、By、BzFor three components of magnetic induction density B on spherical shell；
(5) micro-control processor STM32 judges magnetic induction density Ba、Bb、BcMagnitude relationship, maximum therein is substituted into
In the corresponding function of formula (4), draw tiltangleθ and checkout result is sent to by PC by RS232 Serial Port Lines and show；
Wherein, θ is inclination angle；Ba、Bb、BcMagnetic strength respectively on the position of tunnel magneto resistance (TMR) sensor a, b, c tri-
Answer intensity measurements；
(6) micro-control processor SIM32 is completed after tiltangleθ calculates, then by magnetic induction density Ba、Bb、BcIn, maximum
Two magnetic induction intensity component By、Bx, substitute into the corresponding function of formula (6), resolving deflection angle β will be tied by RS232 Serial Port Lines
Calculation result is sent to PC and shown；
Wherein, β is deflection angle；By、BxRespectively three magnetic induction density Bsa、Bb、BcCorresponding to middle maximum Magnetic
Induction component；
(7) two values are all obtained, and measurement terminates.
Compared with prior art, the beneficial effects of the invention are as follows：
1st, magnetic liquid measuring cell is designed in the present invention, not only can by spherical shell structure to internal magnetic liquid with
And stack permanent magnet therein is suspended in there is provided the stable environment not influenceed by extraneous factor, return solid on the outside of spherical shell
Fixed tunnel magneto resistance (TMR) sensor provides ± 180 ° of full angle measurement spaces, can make magnetic liquid omniazimuthal horizontal
Sensor measures inclination angle and deflection angle in three dimensions simultaneously, effectively simplifies the tilted angular measurement of three dimensions
Process, extends the range of obliquity sensor to greatest extent, realizes the comprehensive measurement in three dimensions.
2nd, magnetic field is excited using stack permanent magnet in the present invention, first, the design for stacking permanent magnet is solved with inclination
The problem of angle change magnetic induction density B rate of change is uneven, the notable precision for improving sensor, when inclination angle occur it is small
During change, magnetic induction density B change is obvious.Secondly, it is not necessary to extrinsic motivated source, the operation using obliquity sensor is simplified
Journey, reduces the structure of obliquity sensor.Compared with existing magnetic liquid obliquity sensor, magnetic liquid omniazimuthal horizontal inclines
Angle transducer operating procedure is more convenient.
3rd, the present invention measures the size of magnetic induction density B using tunnel magneto resistance (TMR) sensor, to realize angle signal
To the conversion of electric signal.Tunnel magneto resistance (TMR) sensor uses LGA (4mm × 4mm × 2.5mm) packing forms, with difference
It is many that induction coil compares small volume.Tunnel magneto resistance (TMR) sensor has very high sensitivity, using 5V dc sources
Powered for it, its sensitivity K is 5mV/Gs.Tunnel magneto resistance (TMR) sensor can accurately complete the collection of signal, lifting
Magnetic liquid omniazimuthal horizontal transducer sensitivity precision, simplifies sensor overall structure.
Brief description of the drawings
Fig. 1 is the overall structure diagram of magnetic liquid omniazimuthal horizontal obliquity sensor of the present invention；
Fig. 2 is the structural representation of the magnetic liquid measuring cell of magnetic liquid omniazimuthal horizontal obliquity sensor of the present invention
Figure；
Fig. 3 is the sectional elevation knot of the magnetic liquid measuring cell of magnetic liquid omniazimuthal horizontal obliquity sensor of the present invention
Structure schematic diagram；
Fig. 4 is a kind of embodiment knot of the stack permanent magnet of magnetic liquid omniazimuthal horizontal obliquity sensor of the present invention
Structure schematic diagram；
Fig. 5 is the establishment of coordinate system schematic diagram of magnetic liquid omniazimuthal horizontal obliquity sensor of the present invention；
Fig. 6 is the structural representation of the leg of magnetic liquid omniazimuthal horizontal obliquity sensor of the present invention；
Fig. 7 is the horizontal base structural representation of magnetic liquid omniazimuthal horizontal obliquity sensor of the present invention；
Fig. 8 is the magnetic liquid measuring cell quadrant of magnetic liquid omniazimuthal horizontal obliquity sensor of the present invention
Function relation curve between introversion bevel angle θ and magnetic induction density B；
Fig. 9 is the principle schematic that magnetic liquid omniazimuthal horizontal obliquity sensor of the present invention measures deflection angle；
Figure 10 is that magnetic liquid omniazimuthal horizontal obliquity sensor of the present invention resolves deflection angle schematic diagram；
In figure, 1. magnetic liquid measuring cells, 2. supports, 3. horizontal bases, 4. stack permanent magnets, 1-1. closure balls
Shell, 1-2. tunnel magneto resistances (TMR) sensor a, 1-3. tunnel magneto resistance (TMR) sensor b, 1-4. tunnel magneto resistance (TMR)
Sensor c, 1-5. connecting rod, 1-6. connection rings, 1-7. magnetic liquids, 4-1. cylinder permanent magnet a, 4-2. cylinder permanent magnets b, 4-
3. cylinder permanent magnet c, 4-4. cylinder permanent magnet d, 4-5. cylinder permanent magnet e, 2-1. semi-circular pillar, 2-2. pillars a, 2-3. are adjusted
Segmented column, 2-4. pillar b, 3-1. leg a mounting holes, 3-2. leg b mounting holes, 3-3. compasses mounting hole, 3-4. legs c are installed
Hole, 3-5. leg d mounting holes, 3-6. fixing bolt through hole a, 3-7. fixing bolt through hole b, 3-8. fixing bolt through holes c, 3-9.
Fixing bolt through hole d.
Embodiment
With reference to embodiments and its accompanying drawing is further described to the present invention：
As shown in figure 1, the overall structure of magnetic liquid omniazimuthal horizontal obliquity sensor of the present invention, including magnetic liquid are surveyed
Measure element 1, support 2, horizontal base 3 and stack permanent magnet 4；The support 2 is fixed on horizontal base by mounting hole；Magnetic
Property liquid measure element 1 be arranged on support 2；The stack permanent magnet 4 is suspended in the magnetic inside magnetic liquid measuring cell 1
In property liquid；The horizontal base 3 is fixed on face to be detected by fixing bolt；
As shown in Fig. 2 the magnetic liquid measuring cell 1 includes closing spherical shell 1-1, tunnel magneto resistance (TMR) sensor a
1-2, tunnel magneto resistance (TMR) sensor b 1-3, tunnel magneto resistance (TMR) sensor c 1-4, connecting rod 1-5, connection ring 1-6
With magnetic liquid 1-7；External diameter 40mm closing spherical shell is built with the magnetic liquid 1-7 and stacking for accounting for spherical shell volume 40%~50%
Formula permanent magnet 4, and be connected by connecting rod 1-5 with connection ring 1-6；4 connecting rod 1-5 are evenly distributed on closing spherical shell 1-1
In horizontal direction largest circumference, each connecting rod 1-5 one end is vertically fixed on spherical shell；The connecting rod 1-5 other end and company
Meet ring 1-6 to be connected, circular connection ring 1-6 is in the outside for closing the largest circumference in the middle part of spherical shell 1-1；Tunnel magneto resistance
(TMR) sensor b 1-3 are fixed on the bottommost on the outside of closing spherical shell 1-1, tunnel magneto resistance (TMR) sensor a 1-2, tunnel
Magneto-resistor (TMR) sensor c 1-4 are located at the outside of closing spherical shell 1-1 horizontal direction largest circumferences, and the two and ball respectively
The heart is on same straight line；
As shown in figure 3, the magnetic liquid measuring cell of magnetic liquid omniazimuthal horizontal obliquity sensor of the present invention is vertical
Cross-section structure, including closing spherical shell 1-1, tunnel magneto resistance (TMR) sensor a 1-2, tunnel magneto resistance (TMR) sensor b 1-
3rd, tunnel magneto resistance (TMR) sensor c 1-4, stack permanent magnet 4, magnetic liquid 1-7；The magnetic liquid 1-7 is a kind of
New functional material, specially a kind of keryl Fe3O4Magnetic liquid, according to volume ratio Fe3O4：Kerosene=8：92 prepare, close
Spend 1.13g/cm3, viscosity is 3.25mPas, and saturation magnetization is 381.5Gs, and ferroso-ferric oxide is nano particle, diameter
Scope in 2~20nm, its average value is 10nm.Described keryl Fe3O4Magnetic liquid, which has, can suspend than its own density
The characteristic of big magnetisable material, can for stack permanent magnet provide one can the static suspended ring in relative gravity direction
Border；The static suspended ring in magnetic field and the relative gravity direction of magnetic liquid offer that stack permanent magnet 4 is excited using itself
Border, provides the relative gravity that can a be measured direction static magnetic field for tunnel magneto resistance (TMR) sensor.
Order of the described stack permanent magnet 4 by 3~5 pieces of thickness identical cylindrical permanent magnets with radius from small to large
Composition is stacked, wherein, the thickness of every piece of cylindrical permanent magnet should be closed in spherical shell radius at 0.05~0.14 times, stack
The gross thickness of permanent magnet should in 0.25~0.7 times of closing spherical shell radius, the radius of cylindrical permanent magnet for 0.05~
In 0.6 times of closing spherical shell radius；As shown in figure 4, the stack of magnetic liquid omniazimuthal horizontal obliquity sensor of the present invention
A kind of embodiment of permanent magnet, described closing spherical shell radius is 20mm, and stack permanent magnet includes cylinder permanent magnet a 4-
1st, cylinder permanent magnet b 4-2, cylinder permanent magnet c 4-3, cylinder permanent magnet d 4-4, cylinder permanent magnet e 4-5；Five pieces of cylinders are forever
The thickness of magnet is 2mm, and radius is followed successively by 10mm, 8mm, 6mm, 4mm, 2mm；The cylinder permanent magnet of five pieces of axial chargings is relied on
Absorption affinity each other, which is stacked, constitutes an entirety；The central axis of five pieces of permanent magnets is overlapped.In above-mentioned specific embodiment
Permanent magnet perigee distance spherical shell minimum point 3mm.But height of the permanent magnet in magnetic liquid is any in general embodiments
's.
Described magnetic liquid omniazimuthal horizontal obliquity sensor also includes A/D analog-digital converters and micro-control processor, institute
Three tunnel magneto resistance (TMR) sensor groups stated into identical, each tunnel magneto resistance (TMR) sensor with an A/D mould
Number converter is connected, and three A/D analog-digital converters are connected with micro-control processor.
The analog electrical signal of three tunnel magneto resistance output, is converted to digital electricity by A/D analog-digital converters ADS1256 successively
Signal, and micro-control processor STM32 progress calculating processing is sent to, micro-control processor will be settled accounts by RS232 Serial Port Lines tie again
Fruit is sent to PC and shown.
Tunnel magneto resistance (TMR) sensor is a commercially available known electronic device, and the sensor has
The linear magnetic sensor of three orthogonal magnetic susceptibility direction of principal axis, when the magnetic line of force in magnetic field is in the same direction with magnetic susceptibility axle, according to
Tunneling magnetoresistance has：
Vx=KBx (1)
Wherein, Vx、Bx, K be respectively tunnel magneto resistance (TMR) sensorAxial output voltage, magnetic flux density measurement
Value, sensitivity；Magnetic induction density B on spherical shell may be divided into three orthogonal components Bx、By、Bz, have：
According to such relation, tunnel magneto resistance (TMR) sensor can measure the magnetic induction density B on spherical shell.This reality
The sensitivity K for applying tunnel magneto resistance in example is 5mV/Gs.
In order to better illustrate the measurement direction of the respective magnetic susceptibility axle of three tunnel magneto resistance (TMR) sensors on spherical shell,
Rectangular coordinate system in space as shown in Figure 5 is set up, i.e., the centre of sphere O using magnetic liquid measuring cell 1 is rectangular coordinate system in space
The connecting line of origin, centre of sphere O and tunnel magneto resistance (TMR) sensor c 1-4 measurement points is Y-axis, centre of sphere O and tunnel magneto resistance
(TMR) connecting line of sensor b 1-3 measurement points is Z axis, the plane that X-axis is constituted perpendicular to Y, Z axis；Original state tunnel magnetoelectricity
Hinder (TMR) sensor b 1-3 measurement directionThe direction of coordinate system of the axle with setting up is consistent；Magnetic liquid is measured
Element 1 is turned clockwise 90 ° centered on X-axis, now tunnel magneto resistance (TMR) sensor c 1-4 measurement direction Axle is consistent with tunnel magneto resistance (TMR) sensor b 1-3 measurement direction；Magnetic liquid measuring cell 1 is inverse centered on X-axis
Hour hands are rotated by 90 °, now tunnel magneto resistance (TMR) sensor a 1-2 measurement directionAxle and tunnel magneto resistance
(TMR) sensor b 1-3 measurement direction is consistent.Tunnel magneto resistance (TMR) sensor hasAxle,Axle,Three, axle
Orthogonal measurement direction, is fixed on three tunnel magneto resistance (TMR) sensors on spherical shellAxle is consistent with X-direction,Axle points to the centre of sphere of spherical shell,Axle perpendicular toAxle,Plane where axle, and in accordance with the right-hand rule；
Support 2 is four legs, the structure of every leg as shown in fig. 6, including semi-circular pillar 2-1, pillar a 2-2,
Adjustable column 2-3, pillar b 2-4；Pillar a 2-2 non-threaded end is connected with semi-circular pillar 2-1's, threaded end and regulation
Post 2-3 is connected, and the adjustable column 2-3 other end is connected with pillar b 2-4 threaded ends.Turn clockwise adjustable column 2-3 when
Pillar a 2-2 are moved upwards, so that the relative position for adjusting magnetic liquid measuring cell and horizontal base realizes obliquity sensor
The purpose of zeroing.Pillar b2-4 one end is connected with horizontal base 3, in the leg installation through-hole of fixed load level base.
Semi-circular pillar 2-1 one end is connected in connection ring 1-6, plays a part of support magnetic liquid measuring cell；
As shown in fig. 7, the structural representation of the horizontal base of magnetic liquid omniazimuthal horizontal obliquity sensor, including four
Foot mounting aperture, leg a 3-1, leg b 3-2, leg c 3-4, leg d 3-5, four fixing bolt through holes, through hole a 3-
6th, through hole b 3-7, through hole c 3-8, compass is installed in through hole d 3-9, compass a mounting hole 3-3, mounting hole 3-3.
Leg is installed in corresponding mounting hole, passes through water of the fixing bolt through hole magnetic liquid omniazimuthal horizontal obliquity sensor
Flat bed is fixed on tested surface, be should be noted when fixed and be should ensure that the direction north shown in compass is passed with tunnel magneto resistance (TMR)
Sensor b 1-2Axle measurement direction is consistent.
As shown in figure 8, using the method for finite element to calculate using on spherical shell using minimum point as origin, at intervals of 0.4 °, four points
One of the size of magnetic induction density B (as shown in phantom in Figure 3) in spherical shell distal extent；As θ=0, magnetic induction density B is most
Greatly, maximum is 895.7Gs；When θ=90 °, magnetic induction density B is minimum, and minimum value is 143.3Gs；Using polynomial regression
Analytic approach determines that the functional relation between magnetic induction density B and tiltangleθ is：
B=f (the θ)=θ of 877.927-14.713 θ+0.0752(90 ° of 0 ° of ＞ θ ＞) (3) coefficient R-Square=
0.99529, data have the very high degree of correlation；Formula can calculate tiltangleθ accordingly.
The device of the present invention can measure the tiltangleθ and deflection angle β in three dimensions.Two angles are introduced separately below
Measure solution process.
Present invention measurement tiltangleθ (relative to the angle of Z axis in rectangular coordinate system in space O) solution process, according to tunnel
The magnetic induction density B on three positions that magneto-resistor (TMR) sensor a 1-2, b 1-3, c 1-4 are measureda、Bb、Bc, and formula
(3), according to three magnetic induction density Bsa、Bb、BcMagnitude relationship determines calculating function, wherein maximum will substitute into corresponding formula
(4) tiltangleθ, is calculated.
Deflection angle β is (relative to the angle of X-axis in rectangular coordinate system in space O, i.e., under original state for present invention measurement) solution
Calculation process, shown in the principle schematic for measuring deflection angle β such as Fig. 9, when calculating tiltangleθ, make use of three magnetic induction density Bsa、
Bb、BcIn maximum, the measurement point that this is most worth is rotated by 360 ° centered on Z axis, its possible position on spherical shell has been determined that
Put, the possible position constitutes circle in circle of the center of circle on Z axis, such as Fig. 9It is shown, straight linePerpendicular to disc, intersection point
ForPoint；Measurement point O1、O3、O4For circleWith the intersection point of two axial planes of XZ, YZ in rectangular coordinate system in space, O2For O1With O3It
Between any point.As measurement point is different, deflection angle β and tunnel magneto resistance (TMR) sensor Three-axis measurement side
To changing；What it is due to stack permanent magnet 3-5 generations is symmetrical magnetic field,Axle and straight lineBetween angle be to incline
Bevel angle θ keeps constant, so circleThe corresponding magnetic induction density B size in upper arbitrfary point it is all equal and can be analyzed to two it is constant
Component Bxy、Bz, such as to O in figure1Shown in the decomposition of measurement point magnetic induction density B.
As shown in Figure 10, existTo stationary component B in planexySynthesis and decomposition and deflection angle β carry out specifically
It is bright；Wherein B1、B2、B3、B4Represent respectively, in circleUpper O1、O2、O3、O4The stationary component B of different measurement point positionsxy；Constant point
Measure Bxy Size is constant in plane, but direction changes with deflection angle β；Original state defines stationary component BxyWithAxle is same
To deflection angle β is stationary component BxyWithThe angle of axle；By to stationary component BxyIn O2Measurement point B2 carries out orthogonal point
Solution, it is known that now deflection angle β is：
Wherein | By| and | Bx| it is that magnetic induction density B exists on spherical shell respectivelyThe absolute value of component on axle.Formula
(5) it is generalized to suitable for ± 180 ° of full angles.
The application process of described magnetic liquid omniazimuthal horizontal obliquity sensor, comprises the following steps：
(1) magnetic liquid omniazimuthal horizontal obliquity sensor is placed, makes tunnel magneto resistance (TMR) sensor of its footDirection north shown in axle measurement direction and compass is consistent, now by fixing bolt by magnetic liquid omniazimuthal horizontal inclination angle
Sensor is fixed on the tested surface for needing to measure inclination angle and deflection angle；
Wherein, centre of sphere O and the connecting line of tunnel magneto resistance (TMR) sensor c 1-4 measurement points are Y-axis, centre of sphere O and tunnel
The connecting line of magneto-resistor (TMR) sensor b 1-3 measurement points is Z axis, the plane that X-axis is constituted perpendicular to Y, Z axis；
(2) zeroing of adjustable column obliquity sensor is rotated：The adjustable column on four legs is rotated, is made at tunnel magneto resistance a, c
In same horizontal line, now tunnel magneto resistance (TMR) sensor a, c are respectiveThree magnetic susceptibility direction of principal axis
On, the outputting measurement value of respective shaft is equal in three axles；Total magnetic induction density B of tunnel magneto resistance (TMR) sensor b measurementsbDeng
In 895.7Gs；Realize that magnetic liquid omniazimuthal horizontal obliquity sensor returns to zero；
Wherein, three tunnel magneto resistances (TMR) sensor is respectively provided withAxle,Axle,Three, axle is orthogonal to be surveyed
Direction is measured, three tunnel magneto resistance (TMR) sensors on spherical shell are fixed onAxle is consistent with X-direction,Axle points to spherical shell
The centre of sphere,Axle perpendicular toAxle,Plane where axle, and in accordance with the right-hand rule；
(3) after tested surface is tilted, 2~3 minutes are stood, treats that obliquity sensor is stable；
(4) tunnel magneto resistance (TMR) sensor output voltage, calculated magnetic induction intensity B are gathereda、Bb、BcSize：Micro-control
Processor STM32 gathers three tunnel magneto resistance (TMR) sensors by A/D analog-digital converter ADS1256, successively, amounts to
Nine road differential output voltage signals；Analog voltage signal is converted to digital voltage signal by analog-digital converter, is forwarded at micro-control
Manage device STM32；Micro-control processor STM32 is by nine digital differential output voltages, according to formula (1) Vx=KBx, calculate respectively
Go out three tunnel magneto resistance (TMR) sensors respectiveThe magnetic induction intensity component B of three axles in directionx、By、
Bz, then recycle formula (2)Calculate tunnel magneto resistance (TMR) sensor a,
Magnetic induction density B on three positions of b, c measurementa、Bb、Bc；
Wherein, Vx、Bx, K be respectively tunnel magneto resistance (TMR) sensorAxial output voltage, magnetic flux density measurement
Value, sensitivity；Bx、By、BzFor three components of magnetic induction density B on spherical shell；
(5) micro-control processor STM32 judges magnetic induction density Ba、Bb、BcMagnitude relationship, maximum therein is substituted into
In the corresponding function of formula (4), draw tiltangleθ and checkout result is sent to by PC by RS232 Serial Port Lines and show；
Wherein, θ is inclination angle；Ba、Bb、BcMagnetic strength respectively on the position of tunnel magneto resistance (TMR) sensor a, b, c tri-
Answer intensity measurements；
(6) micro-control processor SIM32 is completed after tiltangleθ calculates, then by magnetic induction density Ba、Bb、BcIn, maximum
Two magnetic induction intensity component By、Bx, substitute into the corresponding function of formula (6), resolving deflection angle β will be tied by RS232 Serial Port Lines
Calculation result is sent to PC and shown；
Wherein, β is deflection angle；By、BxRespectively three magnetic induction density Bsa、Bb、BcCorresponding to middle maximum Magnetic
Induction component；
(7) two values are all obtained, and measurement terminates.
It is emphasized that embodiment of the present invention is illustrative, rather than it is limited, therefore present invention bag
Include and be not limited to embodiment described in embodiment, it is every by those skilled in the art's technique according to the invention scheme
The other embodiment drawn, also belongs to the application protective scope of the claims.
The present invention does not address part and is applied to prior art.
Claims (4)
1. a kind of magnetic liquid omniazimuthal horizontal obliquity sensor, it is characterized in that the sensor include magnetic liquid measuring cell,
Support, horizontal base and stack permanent magnet；The support is fixed on horizontal base by mounting hole；Magnetic liquid measurement member
Part is rack-mount；The stack permanent magnet is suspended in the magnetic liquid inside magnetic liquid measuring cell；The water
Flat bed is fixed on face to be detected by fixing bolt；
The magnetic liquid measuring cell includes closing spherical shell, tunnel magneto resistance (TMR) sensor a, tunnel magneto resistance (TMR) and passed
Sensor b, tunnel magneto resistance (TMR) sensor c, connecting rod, connection ring and magnetic liquid；Closing spherical shell is built with accounting for spherical shell volume
40%~50% magnetic liquid and stack permanent magnet, and be connected by connecting rod with connection ring；4 connecting rods are uniformly divided
Cloth is in closing spherical shell horizontal direction largest circumference, and one end of each connecting rod is vertically fixed on spherical shell；Connecting rod it is another
End is connected with connection ring, and circular connection ring is in the outside for closing the largest circumference in the middle part of spherical shell；Tunnel magneto resistance (TMR)
Sensor b is fixed on the bottommost on the outside of closing spherical shell, tunnel magneto resistance (TMR) sensor a, tunnel magneto resistance (TMR) sensing
Device c is located at the outside of closing spherical shell horizontal direction largest circumference respectively, and with the centre of sphere on same straight line；
Described stack permanent magnet is stacked with the order of radius from small to large by 3-5 blocks cylindrical permanent magnet and constituted, and cylinder is forever
The thickness of magnet is identical, and the maximum cylinder permanent magnet of diameter is in the top；The cylinder permanent magnet of axial charging is by each other
Absorption affinity stack constitute an entirety；The central axis of permanent magnet is overlapped；
Support is four legs, and every leg includes semi-circular pillar, pillar a, adjustable column, pillar b；The semi-circular pillar is used
To support connection ring, the pillar b is fixed in the corresponding foot mounting aperture of load level base；Pillar a non-threaded end and half
Turned legs are connected, and threaded end is connected with adjustable column, the other end of adjustable column is connected with pillar b threaded ends；
The horizontal base of magnetic liquid omniazimuthal horizontal obliquity sensor includes four foot mounting apertures, and four fixing bolts lead to
Compass is installed in hole, a compass mounting hole, hole；
Described magnetic liquid omniazimuthal horizontal obliquity sensor also includes A/D analog-digital converters and micro-control processor, each tunnel
Road magneto-resistor (TMR) sensor is connected with an A/D analog-digital converter, and three A/D analog-digital converters are and micro-control processor
It is connected.
2. magnetic liquid omniazimuthal horizontal obliquity sensor as claimed in claim 1, it is characterized in that described stack permanent magnetism
Body is preferably to be stacked to constitute by 5 pieces of cylindrical permanent magnets, and the thickness of five pieces of cylinder permanent magnets is 2mm, radius be followed successively by 10mm,
8mm、6mm、4mm、2mm；The radius of described closing spherical shell is 20mm.
3. magnetic liquid omniazimuthal horizontal obliquity sensor as claimed in claim 1, it is characterized in that the magnetic liquid is coal
Oil base Fe3O4Magnetic liquid, according to volume ratio Fe3O4：Kerosene=8：92 prepare；Ferroso-ferric oxide is nano particle, the model of diameter
It is trapped among 2~20nm.
4. the application process of described magnetic liquid omniazimuthal horizontal obliquity sensor as claimed in claim 1, it is characterized in that
Comprise the following steps：
(1) magnetic liquid omniazimuthal horizontal obliquity sensor is placed, makes tunnel magneto resistance (TMR) sensor of its footAxle
Measurement direction unanimously, is now sensed magnetic liquid omniazimuthal horizontal inclination angle by fixing bolt with the direction north shown in compass
Device is fixed on the tested surface for needing to measure inclination angle and deflection angle；
Wherein, centre of sphere O and the connecting line of tunnel magneto resistance (TMR) sensor c 1-4 measurement points are Y-axis, centre of sphere O and tunnel magnetoelectricity
The connecting line for hindering (TMR) sensor b 1-3 measurement points is Z axis, the plane that X-axis is constituted perpendicular to Y, Z axis；
(2) zeroing of adjustable column obliquity sensor is rotated：The adjustable column on four legs is rotated, is in tunnel magneto resistance a, c same
One horizontal line, now tunnel magneto resistance (TMR) sensor a, c are respectiveThree magnetic susceptibility direction of principal axis on, three
The outputting measurement value of respective shaft is equal in axle；Total magnetic induction density B of tunnel magneto resistance (TMR) sensor b measurementsbIt is equal to
895.7Gs；Realize that magnetic liquid omniazimuthal horizontal obliquity sensor returns to zero；
Wherein, three tunnel magneto resistances (TMR) sensor is respectively provided withAxle,Axle,Three orthogonal measurement sides of axle
To being fixed on three tunnel magneto resistance (TMR) sensors on spherical shellAxle is consistent with X-direction,Axle points to the ball of spherical shell
The heart,Axle perpendicular toAxle,Plane where axle, and in accordance with the right-hand rule；
(3) after tested surface is tilted, 2~3 minutes are stood, treats that obliquity sensor is stable；
(4) tunnel magneto resistance (TMR) sensor output voltage, calculated magnetic induction intensity B are gathereda、Bb、BcSize：Micro-control processing
Device STM32 gathers three tunnel magneto resistance (TMR) sensors by A/D analog-digital converter ADS1256, successively, altogether nine tunnels
Differential output voltage signal；Analog voltage signal is converted to digital voltage signal by analog-digital converter, is forwarded to micro-control processor
STM32；Micro-control processor STM32 is by nine digital differential output voltages, according to formula (1) Vx=KBx, three are calculated respectively
Individual tunnel magneto resistance (TMR) sensor is respectiveThe magnetic induction intensity component B of three axles in directionx、By、Bz, so
Formula (2) is recycled afterwardsCalculate tunnel magneto resistance (TMR) sensor a, b, c survey
Magnetic induction density B on three positions of amounta、Bb、Bc；
Wherein, Vx、Bx, K be respectively tunnel magneto resistance (TMR) sensorAxial output voltage, magnetic flux density measurement value, spirit
Sensitivity；Bx、By、BzFor three components of magnetic induction density B on spherical shell；
(5) micro-control processor STM32 judges magnetic induction density Ba、Bb、BcMagnitude relationship, by maximum therein substitute into formula
(4) in corresponding function, draw tiltangleθ and checkout result is sent to by PC by RS232 Serial Port Lines and show；
Wherein, θ is inclination angle；Ba、Bb、BcMagnetic induction respectively on the position of tunnel magneto resistance (TMR) sensor a, b, c tri- is strong
Spend measured value；
(6) micro-control processor SIM32 is completed after tiltangleθ calculates, then by magnetic induction density Ba、Bb、BcIn, two of maximum
Magnetic induction intensity component By、Bx, substitute into the corresponding function of formula (6), knot will be settled accounts by RS232 Serial Port Lines by resolving deflection angle β
Fruit is sent to PC and shown；
Wherein, β is deflection angle；By、BxRespectively three magnetic induction density Bsa、Bb、BcCorresponding to middle maximum、Magnetic induction
Strength component；
(7) two values are all obtained, and measurement terminates.
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