CN113985330A - Comprehensive tester for various magnetic fields based on Arduino - Google Patents
Comprehensive tester for various magnetic fields based on Arduino Download PDFInfo
- Publication number
- CN113985330A CN113985330A CN202111273545.6A CN202111273545A CN113985330A CN 113985330 A CN113985330 A CN 113985330A CN 202111273545 A CN202111273545 A CN 202111273545A CN 113985330 A CN113985330 A CN 113985330A
- Authority
- CN
- China
- Prior art keywords
- magnetic field
- coil
- slide rail
- axis
- arduino
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Images
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R33/00—Arrangements or instruments for measuring magnetic variables
- G01R33/02—Measuring direction or magnitude of magnetic fields or magnetic flux
- G01R33/06—Measuring direction or magnitude of magnetic fields or magnetic flux using galvano-magnetic devices
- G01R33/07—Hall effect devices
-
- G—PHYSICS
- G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
- G09B—EDUCATIONAL OR DEMONSTRATION APPLIANCES; APPLIANCES FOR TEACHING, OR COMMUNICATING WITH, THE BLIND, DEAF OR MUTE; MODELS; PLANETARIA; GLOBES; MAPS; DIAGRAMS
- G09B23/00—Models for scientific, medical, or mathematical purposes, e.g. full-sized devices for demonstration purposes
- G09B23/06—Models for scientific, medical, or mathematical purposes, e.g. full-sized devices for demonstration purposes for physics
- G09B23/18—Models for scientific, medical, or mathematical purposes, e.g. full-sized devices for demonstration purposes for physics for electricity or magnetism
- G09B23/181—Models for scientific, medical, or mathematical purposes, e.g. full-sized devices for demonstration purposes for physics for electricity or magnetism for electric and magnetic fields; for voltages; for currents
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Engineering & Computer Science (AREA)
- Computational Mathematics (AREA)
- Mathematical Analysis (AREA)
- Mathematical Optimization (AREA)
- Mathematical Physics (AREA)
- Pure & Applied Mathematics (AREA)
- Business, Economics & Management (AREA)
- Algebra (AREA)
- Educational Administration (AREA)
- Educational Technology (AREA)
- Theoretical Computer Science (AREA)
- Condensed Matter Physics & Semiconductors (AREA)
- Measuring Magnetic Variables (AREA)
Abstract
The invention discloses a comprehensive tester for various magnetic fields based on Arduino, which adopts devices such as an Arduino single chip microcomputer and a Hall sensor to develop a comprehensive tester capable of measuring various magnetic fields, combines measurement experiments of a constant magnetic field, an alternating magnetic field and a geomagnetic field based on understanding of different magnetic field measurement methods and integration of related experimental equipment, embodies the difference of the constant magnetic field, the alternating magnetic field and the geomagnetic field in an electromagnetic effect, measures the size and the direction of the magnetic field, and is beneficial to helping students to know and understand the distribution condition of the magnetic fields of a current-carrying circular coil and a Helmholtz coil and the component size of the geomagnetic field relative to the parallel ground.
Description
Technical Field
The invention relates to the technical field of physical testing, in particular to a comprehensive tester for multiple magnetic fields based on Arduino.
Background
At present, the progress of modern science and technology makes new technology, new technology and new material continuously come out. In a new environment, the physical experiment can help students to know the development of modern science without the support of basic physics, and the physical experiment reflects the theory principle of the modern science and technology gradually in a small and real way. Many scientific and technological products, new improved products and the like which appear at present intensively represent the change force of modern science and technology. However, some experiments reflecting modern science and technology can be explained and verified only by using scales, spring scales, thermometers, student power supplies, voltages, ammeters, sensitive ammeters and the like, the modern industry or technology development has made great progress and change in precision and performance, and the traditional physical experiment instrument is difficult to represent and express the key contents of the science and technology. Therefore, it is imperative to use new laboratory instruments to replace old, aged physical laboratory instruments.
Magnetic fields are widely used in many fields, and more attention is paid to the measurement of magnetic fields in order to understand the characteristics of the magnetic fields and to make better use of the magnetic fields. The current magnetic field measuring methods of various colleges and universities mainly include Hall effect solenoid magnetic field measurement and electromagnetic induction method alternating magnetic field measurement, and the essence of the magnetic field measuring methods is magnetic induction intensity measurement, and two sets of completely separated equipment are used on experimental equipment, which increases unnecessary burden for spatial arrangement and experimental expenditure of experiments.
Therefore, how to realize the integration of the magnetic field measurement device is a problem that needs to be solved by those skilled in the art.
Disclosure of Invention
In view of the above, the invention provides an Arduino-based multiple magnetic field comprehensive tester, which adopts an Arduino single chip microcomputer and a hall sensor to develop a comprehensive tester capable of measuring multiple magnetic fields, combines measurement experiments of a constant magnetic field, an alternating magnetic field and a geomagnetic field based on understanding of different magnetic field measurement methods and integration of related experimental equipment, embodies the difference of the constant magnetic field, the alternating magnetic field and the geomagnetic field in the electromagnetic effect, measures the size and the direction of the magnetic field, and is beneficial to helping students to know and understand the distribution conditions of the magnetic fields of a current-carrying circular coil and a helmholtz coil and the component size of the geomagnetic field relative to the parallel ground.
In order to achieve the purpose, the invention adopts the following technical scheme:
a comprehensive tester for various magnetic fields based on Arduino comprises a bottom plate, an Arduino single chip microcomputer, an adjustable coil group, a universal ball, a detection coil, a compass, a lead screw slide rail, a magnetic induction intensity display screen, a current and voltage display screen, a single-double coil switch, a direct current and alternating current conversion switch, a wiring terminal and a coil interval scale, wherein the Arduino single chip microcomputer, the adjustable coil group, the universal ball, the detection coil, the compass, the lead screw slide rail, the magnetic induction intensity display screen, the current and voltage display screen, the single-double coil switch, the direct current and alternating current conversion switch, the wiring terminal and the coil interval scale are arranged on the bottom plate;
the Arduino single-chip microcomputer is electrically connected with the universal ball, the magnetic induction intensity display screen and the current and voltage display screen;
the universal ball is fixed on the lead screw slide rail and extends into the space between the adjustable coil groups to realize the sliding in the x-axis direction, the y-axis direction and the z-axis direction;
the detection coil slides between the adjustable coil groups through the lead screw slide rail to realize the sliding in the x-axis direction and the y-axis direction;
the compass is movably fixed on the bottom plate;
the binding post is connected with the adjustable coil group through the alternating current-direct current change-over switch;
the coil spacing graduated scale is fixed on one side of the adjustable coil group;
the single-double coil switch is connected with the adjustable coil group, the current and voltage display screen and the magnetic induction intensity display screen; the single coil or double coil switching-on switching is realized;
the alternating current and direct current change-over switch is connected with the adjustable coil group, the current and voltage display screen and the magnetic induction intensity display screen.
Preferably, the alternating current-direct current change-over switch is a group of switches, and the alternating current or direct current is switched by simultaneously shifting, and the alternating current voltage display screen and the magnetic induction intensity display screen are switched on when the direct current is switched on, and the alternating magnetic field is measured when the alternating current is switched on.
Preferably, the binding posts comprise a direct current binding post and an alternating current binding post which are respectively connected with direct current and alternating current, so that the adjustable coil group respectively generates a stable and constant magnetic field and an alternating magnetic field, the direct current binding post is connected with the positive pole in red, the negative pole in black, and the alternating binding post can be connected with both the positive pole and the negative pole.
Preferably, be provided with the hall piece in the universal ball, hall piece electricity is connected Arduino singlechip.
Preferably, the universal ball comprises a fixed semi-ring, a rotating circular ring and a ball body; the ball body is rotatably fixed at the circle center of the rotating ring, and two ends of the rotating ring, which are in the same rotating direction as the ball body, are rotatably fixed at two ends of the fixed semi-ring.
Preferably, the universal ball is fixed on the lead screw slide rail through a carbon rod in an extending manner, and the circular arc top end of the fixed semi-ring of the universal ball is fixedly connected with the carbon rod; the lead screw slide rail comprises an x-axis slide rail, a y-axis slide rail and a z-axis slide rail, the z-axis slide rail is perpendicular to and slidably connected with the y-axis slide rail, and the x-axis slide rail is perpendicular to and slidably connected with the y-axis slide rail; one end of the carbon rod is connected to the z-axis sliding rail in a sliding mode, and the other end of the carbon rod is fixedly connected with the universal ball.
According to the technical scheme, compared with the prior art, the invention discloses a comprehensive tester for various magnetic fields based on Arduino, wherein devices such as a Helmholtz coil, an Arduino single chip microcomputer, a Hall sensor, a compass, an induction coil and the like are integrated to obtain the comprehensive tester for the magnetic fields which can measure the magnitude and direction of the magnetic fields such as a geomagnetic field, a steady magnetic field, an alternating magnetic field and the like and can be quantitatively researched.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the provided drawings without creative efforts.
FIG. 1 is a schematic structural diagram of a comprehensive tester for various magnetic fields based on Arduino provided by the invention;
FIG. 2 is a schematic view of another angle structure of the tester provided by the present invention;
FIG. 3 is a top view of the apparatus of the present invention;
FIG. 4 is a schematic diagram of a gimbal ball structure provided by the present invention;
FIG. 5 is a circuit diagram of a coil provided by the present invention;
FIG. 6 is a schematic diagram illustrating the relationship between the magnitude of the X-axis induced current and the position of the Helmholtz coil provided by the present invention;
FIG. 7 is a schematic diagram illustrating the relationship between the magnitude and position of the X-axis induced current of the Helmholtz coil provided by the present invention;
FIG. 8 is a schematic diagram illustrating the relationship between the measured induced electromotive force and the angle of the magnetic field coil according to the present invention;
FIG. 9 is a schematic diagram of the present invention illustrating the steady magnetic field in the X-axis direction of a measuring circular coil;
FIG. 10 is a schematic view of the Y-axis steady magnetic field of the measurement circular coil provided by the present invention;
FIG. 11 is a schematic view of the steady magnetic field in the X-axis direction of a Helmholtz coil provided by the present invention;
FIG. 12 is a schematic diagram illustrating the Y-axis steady magnetic field distribution of a Helmholtz coil according to the present invention;
FIG. 13 is a schematic diagram illustrating the distribution of the steady and constant magnetic field in the X-axis direction of the dual coils according to the present invention;
FIG. 14 is a schematic view of a Y-axis steady magnetic field distribution of a dual coil according to the present invention;
FIG. 15 is a schematic diagram showing the comparison between theoretical and experimental values of the geomagnetic field provided by the present invention;
FIG. 16 is a schematic view of a Helmholtz coil provided by the present invention;
FIG. 17 is a schematic view of the magnetic field at a point off the axis of a single circular coil provided by the present invention;
FIG. 18 is a schematic view of the Helmholtz coil magnetic field provided by the present invention.
In the drawings: the device comprises a base plate 1, an adjustable coil group 2, a universal ball 3, a fixed semi-ring 31, a rotating ring 32, a sphere 33, a carbon rod 34, a detection coil 4, a compass 5, a lead screw slide rail 6, a magnetic field intensity display screen 7, a current and voltage display screen 8, a direct current and alternating current change-over switch 9, a single-double coil switch 10, a wiring terminal 11 and a coil interval scale 12.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
The embodiment of the invention discloses a comprehensive tester for various magnetic fields based on Arduino, which comprises a bottom plate 1, an Arduino single chip microcomputer, an adjustable coil group 2, a universal ball 3, a detection coil 4, a compass 5, a lead screw slide rail 6, a magnetic induction intensity display screen 7, a current and voltage display screen 8, a direct current-alternating current conversion switch 9, a single-double coil switch 10, a binding post 11 and a coil interval scale 12, wherein the Arduino single chip microcomputer, the adjustable coil group 2, the universal ball 3, the detection coil 4, the compass 5, the lead screw slide rail 6, the single-double coil switch 10, the binding post 11 and the coil interval scale 12 are arranged on the bottom plate 1;
the Arduino single chip microcomputer is electrically connected with the universal ball 3, the magnetic induction intensity display screen 7 and the current and voltage display screen 8;
the universal ball 3 is fixed on the lead screw slide rail 6 and extends into the space between the adjustable coil groups 2 to realize the sliding in the x-axis direction, the y-axis direction and the z-axis direction;
the detection coil 4 slides between the adjustable coil groups 2 through the lead screw slide rail 6 to realize the sliding in the x-axis direction and the y-axis direction;
the compass 5 can be movably fixed on the bottom plate 1;
the binding post 11 is connected with the adjustable coil group 2 through an alternating current-direct current change-over switch 9;
the coil spacing graduated scale 12 is fixed on one side of the adjustable coil group 2;
the single-double coil switch 10 is connected with the adjustable coil group 2, the current and voltage display screen 8 and the magnetic induction intensity display screen 7; the single coil or double coil switching-on switching is realized;
the alternating current-direct current change-over switch 9 is connected with the adjustable coil group 2, the current-voltage display screen 8 and the magnetic induction intensity display screen 7.
In order to further optimize the technical scheme, the alternating current and direct current change-over switches are a group of switches, alternating current or direct current switching is realized by simultaneously shifting, the current voltage display screen and the magnetic induction intensity display screen are switched on when direct current is switched on, and alternating magnetic field measurement is carried out when alternating current is switched on.
In order to further optimize the technical scheme, the binding posts 11 comprise direct current binding posts and alternating current binding posts which are respectively connected with direct current and alternating current, so that the adjustable coil groups respectively generate a stable and constant magnetic field and an alternating magnetic field, the direct current binding posts are connected with a positive pole in red and a negative pole in black, and the alternating binding posts can be both positive and negative.
In order to further optimize above-mentioned technical scheme, be provided with the hall piece in the universal ball 3, the hall piece electricity is connected Arduino singlechip. And the measurement of a steady magnetic field is realized.
In order to further optimize the above technical solution, the universal ball 3 comprises a stationary half ring 31, a rotating ring 32 and a ball 33; the ball 33 is rotatably fixed at the center of the rotating ring 32, and two ends of the rotating ring 32, which have the same rotating direction as the ball 33, are rotatably fixed at two ends of the stationary half ring 31.
In order to further optimize the technical scheme, the universal ball 33 is fixed on the screw rod slide rail 6 through the carbon rod 34 in an extending manner, and the arc top end of the fixed half ring 31 of the universal ball 33 is fixedly connected with the carbon rod 34; the lead screw slide rail 6 comprises an x-axis slide rail, a y-axis slide rail and a z-axis slide rail, the z-axis slide rail is perpendicular to and connected with the y-axis slide rail in a sliding manner, and the x-axis slide rail is perpendicular to and connected with the y-axis slide rail in a sliding manner; one end of the carbon rod 34 is connected to the z-axis slide rail in a sliding mode, and the other end of the carbon rod 34 is fixedly connected with the universal ball.
In order to further optimize the technical scheme, a special alternating magnetic field tester is adopted to provide the excitation current.
In order to further optimize above-mentioned technical scheme, Arduino singlechip is provided with the usb interface, and the treasured that can connect to charge is the power supply of Arduino singlechip.
In order to further optimize the technical scheme, the adjustable coil group is connected with a single-double coil switch, and a single coil or double coils of the adjustable coil group can be controlled to be switched on.
In order to optimize the technical scheme in one step, the Arduino single chip microcomputer is controlled by a program to convert magnetic signals received by the Hall element into electric signals and output the electric signals. The design of the connecting circuit of the adjustable coil group, the direct current-alternating current change-over switch, the single-double coil switch and the current-voltage display screen is shown in figure 5, and the current-voltage display screen adopts a four-digit double display meter. The single-coil and double-coil switch pins are respectively connected with two coils of the adjustable coil group and the four-position double-display meter, the direct current and alternating current conversion switches are two groups of switches, one group of switch pins are respectively connected with one binding post of one coil, the four-position double-display meter and one group of binding posts, and the other group of switch pins are respectively connected with the other coil and the other binding post of the one group of binding posts. One set of terminals may be dc terminals or ac terminals.
Examples
(1) When a direct current power supply or an alternating current power supply is connected with a binding post on the left side of the instrument panel, the adjustable coil group generates a magnetic field, and the Hall sensor can output the magnetic field to be displayed on a liquid crystal screen on the left side; the magnitude of the magnetic field can be changed by changing the power supply voltage.
(2) The adjustable coil group can be switched into a single-coil or a double-coil by switching the single-double-coil switch. Only any one coil is electrified, namely, the coil is switched into a single coil; energizing the two coils, and switching to a double coil if the distance between the two coils can be moved; if the distance between two energized coils is equal to the radius of the coils, then the pair of coils are Helmholtz coils, which are special double-coil structures.
(3) Wire frame and power and panel right side terminal connection, change mains voltage size and can change the wire frame in the electric current size, the electric current shows at right side display screen.
Magnetic field of current-carrying circular coil and helmholtz coil:
the magnetic field distribution on the axis of the Helmholtz coil is characterized in that a pair of circular coils with the same number of turns, the same winding mode and the same size are coaxially arranged and are electrified with current in the same direction. When the spacing of the two coils is equal to the radius of the circle, the combination is called a Helmholtz coil. As shown in fig. 16.
According to the Biao-Saval law, current elements
Magnetic induction generated at any point in space
Comprises the following steps:
in the formula, mu0Is a vacuum permeability, mu0＝4π×10－7N/A2(ii) a N is the number of coil turns, R is the radius of the current element to the point in space, then for a single circular coil of radius R, the magnitude of the magnetic field generated on the central axis is:
then
When in use
When the temperature of the water is higher than the set temperature,
just two inflection points of the magnetic induction intensity. Analyzing Helmholtz coil formed by combining two circular coils, setting magnetic field as B (x), and when exact expression of residue is not needed, pressing B (x) as (x-x)0) A power expanded 2 n-th order Taylor formula with a Peano-remainder term of formula (4), wherein x is0And n is a positive integer 0.
In the Helmholtz coil, the distance between the two coils is R, and according to the analysis result of the previous single coil, the central point O is just the inflection point of the magnetic field on the axis, so that the coefficient of the 3 rd item in the expansion formula B (x)
Due to the symmetry to the magnetic field, with B (x) B (-x), the coefficient of the derivative of the odd term in the above equation
… are all 0, and then it is found that
The magnetic field B (x) formed on the axis of the Helmholtz coil is shown by formula (5)
The range is relatively uniform.
Magnetic induction intensity on the axis of the Helmholtz coil is
Fig. 17 shows a schematic of the magnetic field at a single circular coil off-axis point. Considering that the magnetic field generated by the circular coil is symmetrical, the distribution of the magnetic field in the whole space generated by the helmholtz coil can be known by only studying any point P (x, y, 0) in the xoy plane.
According to FIG. 17, there are
Then
By an algorithm of vector cross multiplication
Then the magnetic induction at point P generated by the circular coil is
While
Therefore, Bz＝0。
Order to
Expanding according to Taylor series to obtain
The x and y directional components of the magnetic induction can be approximated as:
a helmholtz coil as shown in fig. 18 was constructed on the basis of a single energized circular coil analysis.
Under the new coordinate system, the coordinates of the off-axis point relative to the two coils are respectively
According to the principle of vector superposition of magnetic induction intensity, the distribution of the magnetic field at the outer point of the Helmholtz coil axis is obtained
Wherein, B1x、B2x、B1y、B2yRespectively representing the axial and longitudinal components of the two circular coils at a spatial point; θ represents the angle of direction of the magnetic field.
The principle of measuring the magnetic field by an electromagnetic induction method comprises the following steps:
setting a uniform alternating magnetic field (generated by a coil through which an alternating current is passed)
B＝Bmsinωt (15)
A detection coil in a magnetic field having a magnetic flux of
Wherein N is the number of turns of the detection coil, S is the sectional area of the coil, and theta is
And the angle is included with the normal line of the coil.
Induced electromotive force generated by the coil is
In the formula ofm＝NSωBmcos θ is the magnitude of the induced electromotive force when the coil normal and the magnetic field make an angle θ. When theta is 0, already epsilonm＝NSωBmThe magnitude of the induced electromotive force at this time is the largest. If the electromotive force of the coil at this time is measured by a digital millivoltmeter, the value (effective value) U of the millivoltmeter is representedmaxShould be that
Then
Can calculate BmTo do so.
The principle of the geomagnetic field quantitative measurement experiment is as follows:
a precision compass is placed in the middle of the central axes of the two coils. When the power supply is cut off, the initial degree theta of the magnetic needle is read after the deflection of the needle is stable (pointing to the direction of the geomagnetic field)1. The student power supply is turned on, and a magnetic field B is added in the direction vertical to the geomagnetic field0After the pointer is stabilized again, reading out the degree theta of the deflected magnetic pointer2The geomagnetic field B can be calculated from equation (19).
The method for measuring the magnetic field strength of each direction of a particle comprises the following steps:
most of the devices can only measure the magnetic field intensity in the x-axis direction in measuring the magnetic field intensity, so that the Hall piece is welded again and a 3D printer is used for manufacturing the miniature globe shown in figure 4 by the rotation method of the globe. The Hall piece can rotate on the miniature globe, so that the magnetic field intensity of a mass point of the Hall coil in all directions can be measured.
Example 1
The comprehensive tester for various magnetic fields based on Arduino can measure the magnetic fields of a single coil, a Helmholtz coil and a movable double coil, and realize the measurement of an alternating magnetic field and a geomagnetic field.
A coil measuring step:
s11: adjusting a single-double coil switch to a single coil gear, and electrifying only one coil; the lead screw slide rail XYZ three-axis coordinates connected with the universal ball are in zero, the charger is connected with a USB interface on the instrument to supply power for the Arduino single chip microcomputer, a student power supply is connected with a direct current terminal, and the student power supply is turned on to adjust to proper current (the current cannot be too large so as to avoid burning out the double-position electric meter); keeping two ZY axes in the lead screw slide rail for controlling the position of the universal ball to be constant 0, and moving an X axis to record data every 1cm for twelve groups;
s12: adjusting to a double coil gear; adjusting the coil distance of the adjustable coil group to a position D equal to 10 cm; enabling XYZ three-axis coordinates of a lead screw slide rail connected with a universal ball to be in zero, keeping two ZY axes in the lead screw slide rail for controlling the position of the universal ball to be constant at 0, and recording data every 1cm by moving an X axis to obtain twelve groups;
s13: adjusting to a double coil gear; adjusting the distance between the coils to be 12cm, 16cm or 20 cm; and enabling XYZ three-axis coordinates of a lead screw slide rail connected with the universal ball to be under zero, keeping two ZY axes in the lead screw slide rail for controlling the position of the universal ball to be constant at 0, and recording one datum every 1cm by moving an X axis to obtain twelve groups.
Measuring an alternating magnetic field:
s21: removing the universal ball, and measuring by adopting a detection coil which adopts an electrified solenoid;
s22: measuring the distribution of magnetic fields in different directions when the adjustable coil group forms a Helmholtz coil, so that the effective value of exciting current is 0.800A, taking the center of the circular current coil as the origin of coordinates, measuring one Umax value at intervals of 10 degrees, and keeping the exciting current value unchanged in the measuring process;
s23: the distribution of magnetic fields on the axis of the Helmholtz coil is measured, adjustable coil groups of various magnetic field comprehensive testers are connected in series (note that the polarities can not be connected reversely), the wiring terminals are connected to the alternating current wiring terminals, the effective value of exciting current is still 0.800A, the central points on the axes of the two circular coils are used as the origin of coordinates, a Umax value is measured every 1cm, data are recorded, and a magnetic field distribution curve graph is drawn.
A geomagnetic field measurement step:
s31: a compass of the comprehensive tester for various magnetic fields is placed in the middle of the two coils; the compass adopts a precise compass;
s32: turning off a power supply, and after the pointer deflects stably (points to the direction of the geomagnetic field), rotating the multiple magnetic field comprehensive testers, and adjusting the direction to ensure that the direction of the magnetic field generated by the Helmholtz coil is orthogonal to the direction of the precision compass;
s33: and (3) opening a student power supply to superpose a Helmholtz coil magnetic field, reading out the deflection angle of the magnetic needle after the pointer is stabilized again, and calculating the magnitude of the geomagnetic field parallel to the ground through the magnetic field generated by the Helmholtz coil and the deflection angle of the precise compass.
Example 2
Based on the experimental procedure provided in example 1, measurement data of the alternating magnetic field were obtained.
1) Measuring X-axial alternating magnetic field of Helmholtz coil
The distribution of the magnetic field on the axis is measured by passing an alternating current and compared with the theoretical value. In the experiment, the frequency of the alternating current is 50Hz, and the effective value of the current is 800 mA; changing the x position on the axis using equation Bm＝0.103Umax×10-3(T) to calculate experimental values; the theoretical value is calculated using equation (12). The Helmholtz coil X axial alternating magnetic field shown in Table 1 is the measurement data of the experiment; fig. 6 is a comparison curve of the theoretical value and the experimental value of the present experiment, where the blue curve is the theoretical value of the magnetic field, the red curve is the experimental value of the magnetic field, the abscissa represents the x-axis moving distance, and the ordinate represents the magnitude of the magnetic field.
TABLE 1 Helmholtz coil X axial alternating magnetic field
From the above data, the magnetic field distribution on the axis of the helmholtz coil can be known: the magnetic field is substantially uniform on the X axis inside the helmholtz coil, with the magnetic induction decreasing outside the helmholtz coil. And the magnetic field is mirrored about the center.
2) Measuring Helmholtz coil Y-axial alternating magnetic field
The distribution of the magnetic field on the Y axis is measured by passing an alternating current and compared with a theoretical value. In the experiment, the frequency of the alternating current is 50Hz, and the effective value of the current is 800 mA; changing the Y position on the axis, table 2 is the measurement data for this experiment; fig. 7 is a comparison curve of the theoretical value and the experimental value of the experiment, the blue curve is the theoretical value of the magnetic field, the red curve is the experimental value of the magnetic field, the abscissa represents the y-axis moving distance, and the ordinate represents the magnitude of the magnetic field.
TABLE 2 Helmholtz coil X axial alternating magnetic field
From the above data, it can be seen that the measured values and theoretical values of the experiment are well matched, and the magnetic field of the solenoid on the Y axis is hardly changed along with the change of the distance of the solenoid on the Y axis.
3) Measuring the relationship between induced electromotive force and the angle of field coil
As can be seen from equation (17), the magnitude of the induced electromotive force depends on the magnetic induction intensity as well as the angle between the magnetic field and the coil normal. Next, we change the angle between the magnetic field and the normal line of the coil to analyze the magnitude of the induced electromotive force. Table 3 and fig. 8 are the corresponding data and measurement graphs, respectively, where the blue curve is the theoretical value of the magnetic field, the red curve is the experimental value of the magnetic field, the abscissa represents the angle between the coil and the direction of the magnetic field, and the ordinate represents the magnitude of the magnetic field.
TABLE 3 relationship between measured induced electromotive force and angle of magnetic field coil
As can be seen, the induced electromotive force is the largest at an included angle of zero or 180 degrees and the smallest at an included angle of 90 degrees.
Example 3
Based on the experimental procedure provided in example 1, measurement data of the steady magnetic field was obtained.
1) Measuring the steady magnetic field of the circular coil X axial
And (4) introducing steady direct current, measuring the magnetic field distribution condition of the magnetic field distribution on the X axis, and comparing the magnetic field distribution condition with a theoretical value. In this experiment, the current value was 250 mA; changing the x position on the axis, table 4 is the measurement data for this experiment; fig. 9 is a comparison curve of the theoretical value and the experimental value of the present experiment, where the blue curve is the theoretical value of the magnetic field, the red curve is the experimental value of the magnetic field, the abscissa represents the x-axis moving distance, and the ordinate represents the magnitude of the magnetic field.
TABLE 4 measurement of the X-axial steady magnetic field of a circular coil
It can be seen from fig. 9 and table 4 that the distribution of the magnetic field on the axis of the current-carrying circular coil substantially matches the theoretical value, and the magnetic field intensity at the center of the axis is maximum and gradually decreases toward both sides. The magnetic induction intensity value is the largest at the circle center on the axis of a single circle, the magnetic induction intensity on the axis is slowly reduced along with the increase of the interval with the circle center, the magnetic fields on the two sides of the circle center are symmetrically distributed, the magnetic induction intensity experimental value and the theoretical value of each point are very close, and the coincidence degree of the experimental value and the theoretical value is higher.
2) Constant magnetic field for measuring Y-axis of circular coil
And (4) introducing steady direct current, measuring the magnetic field distribution condition of the magnetic field distribution on the Y axis, and comparing the magnetic field distribution condition with a theoretical value. In this experiment, the current value was 250 mA; changing the x position on the axis, table 5 is the measurement data for this experiment; fig. 10 is a comparison curve of the theoretical value and the experimental value of the present experiment, where the blue curve is the theoretical value of the magnetic field, the red curve is the experimental value of the magnetic field, the abscissa represents the y-axis moving distance, and the ordinate represents the magnitude of the magnetic field.
TABLE 5 measurement of the Y-axial steady magnetic field of the circular coil
| Constant current/mA | x axis/cm | z axis/cm | y axis/cm | Experimental value/Gs of magnetic field | Theoretical value/Gs of magnetic field | Error of the measurement |
| 250.00 | 0.00 | 0.00 | -2.50 | 6.22 | 6.17 | 0.81％ |
| 250.00 | 0.00 | 0.00 | -2.00 | 6.16 | 6.09 | 1.15％ |
| 250.00 | 0.00 | 0.00 | -1.50 | 6.09 | 6.02 | 1.16％ |
| 250.00 | 0.00 | 0.00 | -1.00 | 6.02 | 5.97 | 0.84％ |
| 250.00 | 0.00 | 0.00 | -0.50 | 5.97 | 5.94 | 0.51％ |
| 250.00 | 0.00 | 0.00 | 0.00 | 5.95 | 5.93 | 0.34％ |
| 250.00 | 0.00 | 0.00 | 0.50 | 5.97 | 5.94 | 0.51％ |
| 250.00 | 0.00 | 0.00 | 1.00 | 6.00 | 5.97 | 0.50％ |
| 250.00 | 0.00 | 0.00 | 1.50 | 6.07 | 6.02 | 0.83％ |
| 250.00 | 0.00 | 0.00 | 2.00 | 6.15 | 6.09 | 0.99％ |
| 250.00 | 0.00 | 0.00 | 2.50 | 6.20 | 6.17 | 0.49％ |
The distribution of magnetic field on the horizontal axis of the current-carrying circular coil is approximately consistent with a theoretical value, and the magnetic field intensity at the center of the horizontal axis is minimum and gradually enhanced towards two sides. The magnetic induction intensity value is the smallest at the center of the circle on the horizontal axis of the single ring, and the magnetic induction intensity on the horizontal axis is slowly increased along with the increase of the interval with the center of the circle. The magnetic fields on the two sides of the circle center are symmetrically distributed, the magnetic induction intensity experimental value and the theoretical value of each point are very close, and the experimental value and the theoretical value have high goodness of fit.
3) Measuring steady magnetic field of Helmholtz coil in X axial direction
The Helmholtz coil was energized with a steady direct current, and its magnetic field distribution on the X axis was measured and compared with the theoretical value. In this experiment, the current value was 250 mA; changing the x position on the axis, table 6 is the measurement data for this experiment; fig. 11 is a comparison curve of the theoretical value and the experimental value of the present experiment, where the blue curve is the theoretical value of the magnetic field, the red curve is the experimental value of the magnetic field, the abscissa represents the x-axis moving distance, and the ordinate represents the magnitude of the magnetic field.
TABLE 6 measurement of the steady magnetic field in the X-axial direction of the Helmholtz coil
It can be seen from the figure that both experimentally and theoretically it has been shown that the magnitude of the magnetic field is substantially constant over the intermediate larger range, indicating that the distribution of the magnetic field in this region is relatively uniform, a range of uniform magnetic fields can be generated near the intermediate axis, and the experimental values are in agreement with the theoretical calculations.
4) Measuring steady magnetic field of Helmholtz coil Y axial
The Helmholtz coil was energized with a steady direct current, and its magnetic field distribution on the Y axis was measured and compared with the theoretical value. In this experiment, the current value was 250 mA; changing the Y position on the axis, table 7 is the measurement data for this experiment; fig. 12 is a comparison curve of the theoretical value and the experimental value of the present experiment, where the blue curve is the theoretical value of the magnetic field, the red curve is the experimental value of the magnetic field, the abscissa represents the y-axis movement distance, and the ordinate represents the magnitude of the magnetic field.
TABLE 7 Helmholtz coil Y-axial Steady magnetic field distribution
As can be seen from the figure, the center magnetic field of the double coils in the y-axis direction is maximum, and the two ends are reduced.
5) Measuring a steady magnetic field of a double coil in the X-axis direction
And (3) passing steady direct current to the double coils, measuring the magnetic field distribution condition of the double coils on the X axis, and comparing the magnetic field distribution condition with a theoretical value. In the experiment, the coil distance is 12cm, and the current value is 250 mA; changing the X position on the axis, table 8 is the measurement data for this experiment; fig. 13 is a comparison curve of the theoretical value and the experimental value of the present experiment, where the blue curve is the theoretical value of the magnetic field, the red curve is the experimental value of the magnetic field, the abscissa represents the x-axis moving distance, and the ordinate represents the magnitude of the magnetic field.
TABLE 8 distribution of stable and constant magnetic field in X-axis of double coils
The magnetic field distribution on the transverse shaft of the double coils approximately conforms to the theoretical value, the magnetic field intensity at the shaft center is smaller than that of the single coil, the magnetic field intensity is gradually enhanced towards two sides, the single coil is rapidly reduced towards the outer side, the magnetic fields at two sides of the circle center are symmetrically distributed, the magnetic induction intensity experimental value and the theoretical value of each point are very close, and the coincidence degree of the experimental value and the theoretical value is higher.
6) Measuring a steady magnetic field of a double coil in the Y-axis direction
And (3) passing steady direct current to the double coils, measuring the magnetic field distribution condition of the double coils on the Y axis, and comparing the magnetic field distribution condition with a theoretical value. In the experiment, the coil distance is 12cm, and the current value is 250 mA; changing the X position on the axis, table 9 is the measurement data for this experiment; fig. 14 is a comparison curve of the theoretical value and the experimental value of the present experiment, where the blue curve is the theoretical value of the magnetic field, the red curve is the experimental value of the magnetic field, the abscissa represents the y-axis movement distance, and the ordinate represents the magnitude of the magnetic field.
TABLE 9 distribution of the constant magnetic field in the Y-axis of the twin coils
The magnetic field distribution on the Y axis of the double coils is approximately consistent with a theoretical value, the central magnetic field of the double coils in the direction of the Y axis is the largest, and two ends are reduced.
7) Measuring the magnitude of the magnetic field
The Helmholtz coil is supplied with a constant direct current, and the magnitude of the earth magnetic field can be measured with 2.3.1 and compared with the theoretical value. In the experiment, the coil distance is 10.60cm, and the current value is 250 mA; changing the X position on the axis, table 10 is the measurement data for this experiment; fig. 15 is a comparison curve of the theoretical value and the experimental value of the present experiment, where the blue curve is the theoretical value of the magnetic field, the red curve is the experimental value of the magnetic field, the abscissa indicates the deflection angle of the small magnetic needle, and the ordinate indicates the magnitude of the magnetic field.
TABLE 10 measurement of geomagnetic field data
The measured value and the theoretical value of the geomagnetic field are shown in the figure, the measured geomagnetic field has a little error due to the error of the instrument and the influence of the surrounding environment, the magnetic induction intensity experimental value and the theoretical value after conversion of all angles are very close to each other, and the coincidence degree of the experimental value and the theoretical value is higher.
The invention has the beneficial effects that:
(1) and (3) the versatility is as follows: the device has the characteristics of independence and reorganization, and is wide in application; the integration of equipment and the unification of magnetic field environment are used for realizing the fusion of alternating and constant magnetic field measuring equipment, and the method can be used for the establishment of a permanent magnetic special experiment;
(2) magnetic field measurement method diversity: measuring an alternating magnetic field by using an electromagnetic induction method; the measurement of a constant magnetic field is realized by utilizing the Hall effect; measuring the geomagnetic field by using a small magnetic needle method;
(3) introduction of advanced technologies and products: the direct measurement of the magnetic field size can be carried out by adopting software and hardware such as an Arduino singlechip, a Hall sensor and the like;
(4) and measuring the magnitude of the geomagnetic field by using the small magnetic needle deflection angle. The small magnetic needle deflection angle measurement magnetic field does not need external power supply, the experimental device is simple, the measurement is accurate, difficult experimental data can be obtained by using the simplest method, and great teaching value is achieved;
(5) the device can measure the size of the magnetic field inside and outside the Helmholtz coil in three dimensions and obtain real-time data, and is quick, convenient and accurate; the comprehensive experimental knowledge has a plurality of points, is beneficial to the cultivation of the divergent thinking and the capability of solving complex problems of students, and has wide application.
The embodiments in the present description are described in a progressive manner, each embodiment focuses on differences from other embodiments, and the same and similar parts among the embodiments are referred to each other. The device disclosed by the embodiment corresponds to the method disclosed by the embodiment, so that the description is simple, and the relevant points can be referred to the method part for description.
The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.
Claims (5)
1. A comprehensive tester for various magnetic fields based on Arduino is characterized by comprising a bottom plate, an Arduino single chip microcomputer, an adjustable coil group, a universal ball, a detection coil, a compass, a lead screw slide rail, a magnetic induction intensity display screen, a current and voltage display screen, a single-double coil switch, a direct current and alternating current change-over switch, a wiring terminal and a coil interval scale, wherein the Arduino single chip microcomputer, the adjustable coil group, the universal ball, the detection coil, the compass, the lead screw slide rail, the magnetic induction intensity display screen, the current and voltage display screen, the single-double coil switch, the direct current and alternating current change-over switch, the wiring terminal and the coil interval scale are arranged on the bottom plate;
the Arduino single-chip microcomputer is electrically connected with the universal ball, the magnetic induction intensity display screen and the current and voltage display screen;
the universal ball is fixed on the lead screw slide rail and extends into the space between the adjustable coil groups to realize the sliding in the x-axis direction, the y-axis direction and the z-axis direction;
the detection coil slides between the adjustable coil groups through the lead screw slide rail to realize the sliding in the x-axis direction and the y-axis direction;
the compass is movably fixed on the bottom plate;
the binding post is connected with the adjustable coil group through the alternating current-direct current change-over switch;
the coil spacing graduated scale is fixed on one side of the adjustable coil group;
the single-double coil switch is connected with the adjustable coil group, the current and voltage display screen and the magnetic induction intensity display screen;
the alternating current and direct current change-over switch is connected with the adjustable coil group, the current and voltage display screen and the magnetic induction intensity display screen.
2. The Arduino-based multiple magnetic field comprehensive tester as claimed in claim 1, wherein said terminals include dc terminals and ac terminals for connecting dc and ac power, respectively.
3. The comprehensive tester of various magnetic fields based on Arduino of claim 1, characterized in that, be provided with the hall piece in the universal ball, the hall piece electricity is connected Arduino singlechip.
4. The Arduino-based multiple magnetic field comprehensive tester as claimed in claim 1, wherein said gimbaled ball comprises a stationary half ring, a rotating ring and a ball; the ball body is rotatably fixed at the circle center of the rotating ring, and two ends of the rotating ring, which are in the same rotating direction as the ball body, are rotatably fixed at two ends of the fixed semi-ring.
5. The Arduino-based multiple magnetic field comprehensive tester as claimed in claim 4, wherein the universal ball is fixed on the lead screw slide rail by extending a carbon rod, and the arc top end of the fixed half ring of the universal ball is fixedly connected with the carbon rod; the lead screw slide rail comprises an x-axis slide rail, a y-axis slide rail and a z-axis slide rail, the z-axis slide rail is perpendicular to and slidably connected with the y-axis slide rail, and the x-axis slide rail is perpendicular to and slidably connected with the y-axis slide rail; one end of the carbon rod is connected to the z-axis sliding rail in a sliding mode, and the other end of the carbon rod is fixedly connected with the universal ball.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111273545.6A CN113985330A (en) | 2021-10-29 | 2021-10-29 | Comprehensive tester for various magnetic fields based on Arduino |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111273545.6A CN113985330A (en) | 2021-10-29 | 2021-10-29 | Comprehensive tester for various magnetic fields based on Arduino |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN113985330A true CN113985330A (en) | 2022-01-28 |
Family
ID=79744534
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202111273545.6A Pending CN113985330A (en) | 2021-10-29 | 2021-10-29 | Comprehensive tester for various magnetic fields based on Arduino |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN113985330A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN117647762A (en) * | 2024-01-30 | 2024-03-05 | 华中科技大学 | Method for measuring electromagnetic field space bit type distribution |
-
2021
- 2021-10-29 CN CN202111273545.6A patent/CN113985330A/en active Pending
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN117647762A (en) * | 2024-01-30 | 2024-03-05 | 华中科技大学 | Method for measuring electromagnetic field space bit type distribution |
| CN117647762B (en) * | 2024-01-30 | 2024-04-23 | 华中科技大学 | Method for measuring electromagnetic field space bit type distribution |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP5818267B2 (en) | Method and apparatus for producing a uniform magnetic field | |
| JP6766333B2 (en) | Micromagnetic material detection sensor and foreign matter detection device | |
| Alatawneh et al. | Design of a novel test fixture to measure rotational core losses in machine laminations | |
| CN113985330A (en) | Comprehensive tester for various magnetic fields based on Arduino | |
| Vogel et al. | Rotatable small permanent magnet array for ultra-low field nuclear magnetic resonance instrumentation: A concept study | |
| Qin et al. | An ultra-low magnetic field thermal demagnetizer for high-precision paleomagnetism | |
| CN105455806A (en) | Brain magnetic signal probe, sensor and collecting system based on GMI effect | |
| CN216560958U (en) | Comprehensive tester for various magnetic fields based on Arduino | |
| CN105301549B (en) | A kind of method and system for testing current transformer magnetic screen using three-dimensional magnetic field | |
| Dinale et al. | Generation of long prolate volumes of uniform magnetic field in cylindrical saddle-shaped coils | |
| CN110764033A (en) | Small-sized multifunctional three-dimensional magnetoelectric test system | |
| RU2308095C1 (en) | Device for researching loading characteristics of a current supply | |
| Misakian | ELF electric and magnetic field measurement methods | |
| RU2718641C1 (en) | Method and device for permanent magnets identification by volume magnetization | |
| CN114114109B (en) | Method for measuring micro deformation based on anti-Helmholtz coil | |
| CN110967396B (en) | Giant magneto-impedance effect biomagnetic measuring device based on magnetic bead concentration and simulated lesion body shape | |
| Sobral | Development of a metal detector for smartphones and its use in the teaching laboratory | |
| RU2269823C1 (en) | Installation for testing vorticity electric field | |
| CN111199673A (en) | Faraday's law of electromagnetic induction ration experimental apparatus | |
| CN105321409B (en) | It offsets Ampere's law tester from magnetic field and horizontal earth's magnetic field is disturbed | |
| CN209928756U (en) | Digital ampere force tester | |
| CN211555273U (en) | Faraday's law of electromagnetic induction ration experimental apparatus | |
| JP2838106B2 (en) | Nuclear magnetic resonance imaging equipment | |
| CN111060861B (en) | Atomic magnetometer gradient tolerance calibrating device | |
| Eroğlu et al. | Two alternatives for magnetic resonance electrical impedance tomography: injected or induced current |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |