CN107228649B - Automatic fluxgate theodolite for absolute geomagnetic observation - Google Patents

Abstract

The utility model provides an automatic fluxgate theodolite for absolute geomagnetic observation, which comprises: the device comprises a supporting mechanism (1), a two-dimensional non-magnetic rotating mechanism (2), a measuring unit (3) and a master controller; the two-dimensional non-magnetic rotating mechanism (2) comprises a horizontal non-magnetic rotating unit and a vertical non-magnetic rotating unit; the measuring unit (3) comprises: parallel support (3.1), laser instrument (3.2), single component fluxgate probe (3.3) and electronic level sensor (3.4). The advantages are that: a laser is introduced into the fluxgate theodolite, so that the accuracy of the alignment marker is ensured; the horizontal rotation and the vertical rotation of the single-component fluxgate probe can be automatically and highly accurately realized, and finally the automatic and highly-accurate measurement of the geomagnetic deflection angle D and the geomagnetic inclination angle I is realized.

Description

An Automatic Fluxgate Theodolite for Absolute Geomagnetic Observation

technical field

The invention belongs to the technical field of geomagnetic observation, and in particular relates to an automatic fluxgate theodolite for absolute geomagnetic observation.

Background technique

A fluxgate theodolite is an instrument used to measure absolute geomagnetic parameters, generally including a fluxgate sensor and an ordinary theodolite; an ordinary theodolite is equipped with a telescope. The fluxgate sensor is fixed on the telescope, and the magnetic axis of the fluxgate sensor is basically parallel to the optical axis of the telescope. The fluxgate theodolite can measure the geomagnetic declination D and geomagnetic inclination I. Taking the measurement of the geomagnetic declination D as an example, the measurement principle is as follows: firstly, manually rotate the telescope, and rely on naked eye observation to align the telescope with the marker. At this time, the marker azimuth α is obtained through the theodolite scale; Turn the fluxgate sensor until the magnetic field measured by the fluxgate sensor is 0, which is the vertical direction of the geomagnetic horizontal strength H. At this time, the reading of the theodolite horizontal reading plate is β, therefore, β+90° is the geomagnetic north direction m; and with the help of the azimuth angle α of the sign, the declination D of the geomagnetic field can be calculated.

The above-mentioned method of relying on the fluxgate theodolite to measure the geomagnetic declination D and the geomagnetic inclination I has the following deficiencies:

(1) Using the naked eye observation method to align the telescope with the landmarks, there will inevitably be large observation errors, thereby reducing the measurement accuracy of the final measured geomagnetic declination D and geomagnetic inclination I ;

(2) Turning the fluxgate sensor manually and relying on visual observation to determine the position where the magnetic field is 0 still inevitably has large observation errors, which further reduces the measurement accuracy.

Contents of the invention

Aiming at the defects in the prior art, the present invention provides an automatic fluxgate theodolite for absolute geomagnetic observation, which can effectively solve the above problems.

The technical scheme that the present invention adopts is as follows:

The invention provides an automatic fluxgate theodolite for absolute geomagnetic observation, comprising: a support mechanism (1), a two-dimensional non-magnetic rotating mechanism (2), a measuring unit (3) and a general controller;

Wherein, the support mechanism (1) includes an upper panel (1.1), a lower panel (1.2) and a column (1.3); the upper panel (1.1) and the lower panel (1.2) are horizontally arranged symmetrically up and down; the column The number of (1.3) is at least two, fixedly installed between the upper panel (1.1) and the lower panel (1.2);

The two-dimensional non-magnetic rotating mechanism (2) includes a horizontal non-magnetic rotating unit and a vertical non-magnetic rotating unit; the horizontal non-magnetic rotating unit is used to rotate the measuring unit (3) in the horizontal space, including: Magnetic axis frame (2.1), first vertical axis (2.2), second vertical axis (2.3), first circular grating code disc (2.4), first laser reading head (2.5), first piezoelectric ceramic ring (2.6 ) and the first piezoelectric motor (2.7);

The non-magnetic shaft frame (2.1) is vertically arranged, and the bottom center and top center of the non-magnetic shaft frame (2.1) are respectively fixedly installed with the first vertical shaft (2.2) and the second vertical shaft (2.3); Wherein, the bottom of the first vertical shaft (2.2) is rotatably mounted on the center of the lower panel (1.2) through a bearing; the first piezoelectric ceramic ring (2.6) is located at the center of the lower panel (1.2) above, and the center of the first piezoelectric ceramic ring (2.6) is fixedly sleeved on the second vertical shaft (2.3), and the first piezoelectric motor (2.7) is fixedly installed on the lower panel ( 1.2), and the output end of the first piezoelectric motor (2.7) is in close contact with the surface of the first piezoelectric ceramic ring (2.6), and the first piezoelectric motor (2.7) passes through the The first piezoelectric ceramic ring (2.6) drives the second vertical shaft (2.3) to rotate in the horizontal space, and then drives the non-magnetic shaft frame (2.1) to rotate in the horizontal space; the second vertical shaft ( The top of 2.3) is rotatably mounted on the center of the upper panel (1.1) through a bearing and extends above the upper panel (1.1); the first circular grating code disc (2.4) is located on the upper panel ( 1.1), and the center of the first circular grating code wheel (2.4) is fixedly connected to the second vertical axis (2.3), and the first laser reading head (2.5) is connected to the first circular grating The code wheel (2.4) is connected to read the rotation angle value measured by the first circular grating code wheel (2.4);

The vertical non-magnetic rotating unit includes a horizontal axis (2.8), a second circular grating code disc (2.9), a second laser reading head (2.10), a second piezoelectric ceramic ring (2.11) and a second piezoelectric motor (2.12 ); the horizontal shaft (2.8) is arranged horizontally between the left side beam and the right side side beam of the non-magnetic shaft frame (2.1), and the right end of the horizontal shaft (2.8) is rotatably mounted through a bearing At the center of the right side beam; the second piezoelectric ceramic ring (2.11) is located inside the right side beam, and the center of the second piezoelectric ceramic ring (2.11) is fixedly sleeved on the At the right end of the horizontal shaft (2.8), the second piezoelectric motor (2.12) is fixedly installed on the inner side of the right longitudinal beam, and the output end of the second piezoelectric motor (2.12) is connected to the The surface of the second piezoelectric ceramic ring (2.11) is in close contact, and the second piezoelectric motor (2.12) drives the horizontal axis (2.8) to rotate in the vertical space through the second piezoelectric ceramic ring (2.11); The left end of the horizontal shaft (2.8) is rotatably mounted on the center of the left longitudinal beam through a bearing and extends to the outside of the left longitudinal beam; the second circular grating code disc (2.9) is located on the The outside of the left longitudinal beam, and the center of the second circular grating code disc (2.9) is fixedly connected to the left end of the horizontal axis (2.8), and the second laser reading head (2.10) is connected to the second The circular grating code wheel (2.9) is connected to read the rotation angle value measured by the second circular grating code wheel (2.9);

The measuring unit (3) includes: a parallel support (3.1), a laser (3.2), a single-component fluxgate probe (3.3) and an electronic level sensor (3.4); the geometric center of the parallel support (3.1) is provided with a The installation hole matching the horizontal axis (2.8); the parallel bracket (3.1) is fixedly installed in the center of the horizontal axis (2.8) through the installation hole; the upper and lower ends of the parallel bracket (3.1) are installed The laser (3.2) and the single-component fluxgate probe (3.3) are arranged in parallel; the electronic level sensor (3.4) is fixedly installed on the side of the parallel bracket (3.1);

The general controller is respectively connected with the first laser reading head (2.5), the first piezoelectric motor (2.7), the second laser reading head (2.10), and the second piezoelectric motor (2.12) , the laser (3.2), the single-component fluxgate probe (3.3) and the electronic level sensor (3.4) are electrically connected.

Preferably, the support mechanism (1) further includes adjustment screws (1.4); the number of adjustment screws (1.4) is three, and are fixedly installed at the bottom of the lower panel (1.2) at equal intervals.

Preferably, it also includes: a marker position sensor and a data collector; the marker position sensor is connected to the general controller through the data collector.

Preferably, the marker position sensor is a position measurement device based on a PSD sensor, including an outer casing (4.1), a beam splitter (4.2), a reflector (4.3) and a PSD position sensor (4.4);

The outer shell (4.1) is a cavity structure with an open front; the beam splitter (4.2) is obliquely fixed inside the outer shell (4.1), and the splitting surface of the beam splitter (4.2) and The axis forms an included angle of 45 degrees; the centerline of the splitting surface of the beam splitter (4.2) is the centerline A, and the centerline A communicates with the front opening of the outer casing (4.1); in the outer casing (4.1) The inner wall of the rear end of the beam splitter (4.2) is located on the transmitted light path passing through the center line A, and the PSD position sensor (4.4) is fixedly installed;

The reflection mirror (4.3) is obliquely fixed to the bottom wall of the outer housing (4.1), the reflection surface of the reflection mirror (4.3) is arranged parallel to the beam splitting surface of the beam splitter (4.2), and the The centerline of the reflective surface of the reflector (4.3) is the centerline B, and the centerline B is located directly below the centerline A. Therefore, the laser incident horizontally on the centerline B of the reflector (4.3) goes upward through the reflector (4.3) After reflection, it is incident vertically to the position of the center line A of the beam splitter (4.2), and after being reflected by the beam splitter (4.2), it is horizontally incident to the PSD position sensor (4.4) and detected by the PSD position sensor (4.4) The initial orientation of the incident laser in the horizontal plane.

Preferably, the vertical distance from the reflector (4.3) to the beam splitter (4.2) is adjustable;

It also includes a beam splitter support frame (4.6); the beam splitter (4.2) is fixed to the inner cavity of the outer casing (4.1) through the beam splitter support frame (4.6);

A light transmission hole (4.7) is opened on the top of the outer housing (4.1) and on the reflected light path of the beam splitter (4.2) passing through the central line A.

The automatic fluxgate theodolite provided by the invention for absolute geomagnetic observation has the following advantages:

(1) The laser is used to replace the traditional markers, and the laser is used to align the markers, which can effectively ensure the accuracy of the alignment markers, thereby ensuring the measurement accuracy of the measured geomagnetic declination D and geomagnetic inclination I ;

(2) A two-dimensional non-magnetic rotating mechanism carrying a single-component fluxgate probe is designed, which can automatically and precisely realize the horizontal rotation and vertical rotation of the single-component fluxgate probe, and finally realize the geomagnetic declination D and geomagnetic inclination I automatic measurement of

(3) A marker position sensor with a special structure is designed, which can ingeniously realize the azimuth measurement of two incident lasers at different heights by the PSD sensor at the same position, thereby reducing the measurement when the front and rear mirrors are aligned with the markers errors and improve the accuracy of geomagnetic field measurement.

Description of drawings

Fig. 1 is the first three-dimensional structure schematic diagram of the automatic fluxgate theodolite for absolute geomagnetic observation provided by the present invention;

Fig. 2 is the 2nd three-dimensional structure schematic diagram of the automatic fluxgate theodolite for absolute geomagnetic observation provided by the present invention;

Fig. 3 is the 3rd three-dimensional structure schematic diagram of the automatic fluxgate theodolite for absolute geomagnetic observation provided by the present invention;

Fig. 4 is the first three-dimensional structure schematic diagram of the automatic fluxgate theodolite for absolute geomagnetic observation provided by the present invention when no column is installed;

Fig. 5 is the 2nd three-dimensional structure schematic diagram when the automatic fluxgate theodolite for absolute geomagnetic observation provided by the present invention is not equipped with a column;

6 is a schematic diagram of the first three-dimensional structure of the measuring unit provided by the present invention;

Fig. 7 is the second three-dimensional structural schematic diagram of the measurement unit provided by the present invention;

FIG. 8 is a schematic diagram of a three-dimensional structure of a marker position sensor provided by the present invention;

Fig. 9 is a schematic structural view of the marker position sensor provided by the present invention when the outer shell is not shown;

Fig. 10 is a schematic diagram of the measurement of the incident laser azimuth at the first height by the marker position sensor;

Fig. 11 is a schematic diagram of the measurement principle of the incident laser azimuth at the second height by the marker position sensor;

Fig. 12 is a schematic diagram of the measurement principle of the actual magnetic declination D.

Implementation

In order to make the technical problems, technical solutions and beneficial effects solved by the present invention clearer, the present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described here are only used to explain the present invention, not to limit the present invention.

The present invention provides an automatic fluxgate theodolite for absolute geomagnetic observation, which can be used for absolute geomagnetic measurement in the fields of resource exploration, geomagnetic detection, geodetic exploration, geomagnetic navigation, etc. The main features are summarized as follows:

(1) Fixedly install the single-component fluxgate probe and the laser on the non-magnetic axis frame absolutely parallel, and replace the traditional marker with the PSD position sensor. Therefore, the laser and the PSD position sensor cooperate to align the marker. , the laser emitted by the laser is projected onto the sensing window of the PSD position sensor, and the output signal of the PSD position sensor is used to determine whether the laser is aligned with the marker. The method of aligning the laser with the marker can effectively ensure the accuracy of the marker. Thereby ensuring the measurement accuracy of the measured geomagnetic declination D and geomagnetic inclination I ;

(2) A two-dimensional non-magnetic rotating mechanism carrying a single-component fluxgate probe is designed. The two-dimensional non-magnetic rotating mechanism includes a horizontal non-magnetic rotating unit and a vertical non-magnetic rotating unit, a horizontal non-magnetic rotating unit and a vertical non-magnetic The rotation unit is a closed-loop control system composed of a non-magnetic piezoelectric motor, a laser reading head and a circular grating code disc, so that the horizontal rotation and vertical rotation of the single-component fluxgate probe can be realized automatically and with high precision, and finally the geomagnetic declination D and automatic measurement of geomagnetic inclination I ;

(3) A marker position sensor with a special structure is designed, which can ingeniously realize the azimuth measurement of two incident lasers at different heights by the PSD sensor at the same position, thereby reducing the measurement when the front and rear mirrors are aligned with the markers The error further improves the measurement accuracy of the geomagnetic declination D and the geomagnetic inclination I.

Below in conjunction with accompanying drawing, the present invention is introduced in detail:

Referring to Fig. 1-Fig. 5, the automatic fluxgate theodolite for absolute geomagnetic observation includes: a support mechanism 1, a two-dimensional non-magnetic rotating mechanism 2, a measuring unit 3 and a general controller. The following is a detailed introduction to each component:

The support mechanism 1 is the load-bearing infrastructure of the entire automated fluxgate theodolite, including an upper panel 1.1, a lower panel 1.2 and a column 1.3; the upper panel 1.1 and the lower panel 1.2 are symmetrically arranged horizontally up and down; the number of columns 1.3 is at least two, fixed Installed between the upper panel 1.1 and the lower panel 1.2; the support mechanism 1 also includes adjustment screws 1.4; the number of adjustment screws 1.4 can be set to 3, fixedly installed at the bottom of the lower panel 1.2 at equal intervals, through the adjustment function of the adjustment screws, The levelness of the entire instrument can be adjusted.

The two-dimensional non-magnetic rotating mechanism 2 is a mechanism for realizing the horizontal rotation and vertical rotation of the single-component fluxgate probe while accurately measuring the rotation angle. Since the single-component fluxgate probe has very high non-magnetic requirements for the working environment, the two-dimensional rotating mechanism must be non-magnetic.

The two-dimensional non-magnetic rotating mechanism includes a horizontal non-magnetic rotating unit and a vertical non-magnetic rotating unit; the horizontal non-magnetic rotating unit is used to rotate the measuring unit 3 in the horizontal space, including: non-magnetic axis frame 2.1, first vertical axis 2.2, The second vertical axis 2.3, the first circular grating code disc 2.4, the first laser reading head 2.5, the first piezoelectric ceramic ring 2.6 and the first piezoelectric motor 2.7;

The non-magnetic shaft frame 2.1 is vertically arranged, and the bottom center and the top center of the non-magnetic shaft frame 2.1 are respectively fixedly installed with the first vertical shaft 2.2 and the second vertical shaft 2.3; wherein, the bottom of the first vertical shaft 2.2 is rotatably installed on the bottom through a bearing. The center position of the panel 1.2; the first piezoelectric ceramic ring 2.6 is located above the lower panel 1.2, and the center of the first piezoelectric ceramic ring 2.6 is fixedly sleeved on the second vertical shaft 2.3, and the first piezoelectric motor 2.7 is fixedly installed on the upper surface of the lower panel 1.2, and the output end of the first piezoelectric motor 2.7 is in close contact with the surface of the first piezoelectric ceramic ring 2.6, and the first piezoelectric motor 2.7 drives the second vertical motor through the first piezoelectric ceramic ring 2.6 The shaft 2.3 rotates in the horizontal space, and then drives the non-magnetic shaft frame 2.1 to rotate in the horizontal space; the top of the second vertical shaft 2.3 is rotatably mounted on the center of the upper panel 1.1 through a bearing and extends to the top of the upper panel 1.1; 1. The circular grating code disc 2.4 is located above the upper panel 1.1, and the center of the first circular grating code disc 2.4 is fixedly connected to the second vertical axis 2.3, and the first laser reading head 2.5 is connected to the first circular grating code disc 2.4. To read the rotation angle value measured by the first circular grating code wheel 2.4;

The vertical non-magnetic rotation unit includes a horizontal axis 2.8, a second circular grating code disc 2.9, a second laser reading head 2.10, a second piezoelectric ceramic ring 2.11 and a second piezoelectric motor 2.12; the horizontal axis 2.8 is horizontally arranged on the non-magnetic axis frame 2.1 between the left side beam and the right side beam, and the right end of the transverse shaft 2.8 is rotatably installed in the center of the right side beam through a bearing; the second piezoelectric ceramic ring 2.11 is located on the inner side of the right side beam, and The center of the second piezoelectric ceramic ring 2.11 is fixedly sleeved on the right end of the horizontal shaft 2.8, the second piezoelectric motor 2.12 is fixedly installed on the inner side of the right side beam, and the output end of the second piezoelectric motor 2.12 is connected to the second The surface of the piezoelectric ceramic ring 2.11 is in close contact, and the second piezoelectric motor 2.12 drives the horizontal axis 2.8 to rotate in the vertical space through the second piezoelectric ceramic ring 2.11; the left end of the horizontal axis 2.8 is rotatably installed on the left longitudinal beam through a bearing The center position extends to the outside of the left longitudinal beam; the second circular grating code disc 2.9 is located outside the left longitudinal beam, and the center of the second circular grating code disc 2.9 is fixedly connected to the left end of the horizontal axis 2.8, and the second laser The reading head 2.10 is connected with the second circular grating code wheel 2.9 for reading the rotation angle value measured by the second circular grating code wheel 2.9;

It can be seen that both the horizontal non-magnetic rotating unit and the vertical non-magnetic rotating unit are closed-loop control systems composed of a non-magnetic piezoelectric motor, a laser reading head and a circular grating code disc. Specifically, for the horizontal non-magnetic rotating unit, the horizontal space rotation is realized by controlling the first piezoelectric motor; the horizontal rotation angle can be read by the first laser reading head. For the vertical non-magnetic rotating unit, the vertical space rotation is realized by controlling the second piezoelectric motor; the vertical rotation angle can be read by the second laser reading head. Thus, a high-precision and automatic rotation of the single-component fluxgate probe is realized.

The driving mechanism of the piezoelectric motor and the piezoelectric ceramic ring ensures that the driving mechanism is non-magnetic and will not interfere with the measurement of the single-component fluxgate probe.

Referring to Fig. 6-Fig. 7, the measurement unit 3 includes: a parallel support 3.1, a laser 3.2, a single-component fluxgate probe 3.3 and an electronic level sensor 3.4;

The geometric center of the parallel support 3.1 is provided with a mounting hole matching the horizontal axis 2.8; the parallel support 3.1 is fixedly installed in the center of the horizontal axis 2.8 through the mounting hole; the upper and lower ends of the parallel support 3.1 are equipped with a parallel laser 3.2 and a single component The fluxgate probe 3.3; the electronic level sensor 3.4 is fixedly installed on the side of the parallel support 3.1; in the initial installation process, since the laser 3.2 and the single-component fluxgate probe 3.3 are all fixed on the parallel support, it can ensure that the laser 3.2 and the single component fluxgate probe 3.3 are fixed on the parallel support. The absolute horizontality of the component fluxgate probe 3.3 ensures absolute geomagnetic measurement accuracy.

Markers are auxiliary objects in absolute geomagnetic surveys. Traditional markers are cement or marble piers fixed at specific positions. When combined with a telescope, they can only be aligned with the naked eye.

The automatic fluxgate theodolite provided by the present invention does not need to use a telescope at all, but innovatively uses a laser, and the corresponding marker uses a PSD position sensor. Therefore, the laser and the PSD position sensor cooperate to achieve high-precision alignment marks things.

In addition, in the process of automatic absolute geomagnetic measurement, in order to eliminate the angle between the optical axis of the laser and the axis of the fluxgate probe, it is usually necessary to align the markers twice by aligning the front mirror and aligning the reverse mirror, thereby eliminating the reduction Instrument installation error. Wherein, positive mirror alignment means that the laser is positioned above the fluxgate probe; reverse mirror alignment means that the laser is positioned below the fluxgate probe. Therefore, if a conventional PSD position sensor is used, it is necessary to install two identical PSD position sensors on the upper and lower sides to achieve front mirror alignment and reverse mirror alignment respectively. This method has the following disadvantages: (1) Two PSD position sensors need to be installed, which increases the installation cost; (2) The upper and lower PSD position sensors must be completely parallel and coaxial, otherwise errors in alignment with markers will be introduced , therefore, the installation accuracy is very strict; (3) Even if the PSD position sensor of the exact same model is purchased, since the performance of the two PSD position sensors cannot be exactly the same, there will still be differences between the two PSD position sensors And increase the measurement error.

Therefore, the inventor innovatively proposed a new type of position measurement device based on the PSD position sensor, which can realize the azimuth measurement of two incident lasers at different heights by the PSD sensor at the same position, and completely solve the shortcomings of the above-mentioned traditional methods.

Referring to Figures 8-9, the PSD-based marker position sensor includes an outer housing 4.1, a beam splitter 4.2, a mirror 4.3 and a PSD position sensor 4.4;

The outer casing 4.1 is a cavity structure with an open front; the beam splitter 4.2 is obliquely fixed inside the outer casing 4.1, specifically, the beam splitter 4.2 can be fixed in the inner cavity of the outer casing 4.1 through the beam splitter support frame 4.6.

In addition, the splitting surface of the beam splitter 4.2 is at an angle of 45 degrees to the axis; the center line of the splitting face of the beam splitting mirror 4.2 is the center line A, and the center line A communicates with the front opening of the outer casing 4.1; at the rear of the outer casing 4.1 A PSD position sensor 4.4 is fixedly installed on the transmission light path passing through the center line A of the beam splitter 4.2 on the inner wall of the end; a filter 4.5 can also be fixedly installed in front of the photosensitive surface of the PSD position sensor 4.4. On the top of the outer housing 4.1 and on the reflected light path passing through the centerline A of the beam splitter 4.2, a light-transmitting hole 4.7 is opened.

Reflector 4.3 is obliquely fixed on the bottom wall of outer casing 4.1, and the reflective surface of reflector 4.3 is arranged parallel to the splitting surface of beam splitter 4.2, and the centerline of the reflective surface of reflector 4.3 is centerline B, and centerline B is located at the center Directly below the line A, therefore, the laser incident horizontally on the center line B of the mirror 4.3, after being reflected upward by the mirror 4.3, is vertically incident on the position of the center line A of the beam splitter 4.2, and then passes through the beam splitter 4.2 After the reflection, the laser light is horizontally incident on the PSD position sensor 4.4, and the orientation of the initial incident laser light on the horizontal plane is detected by the PSD position sensor 4.4.

Of course, in practical applications, in order to adapt to different usage scenarios, it can be designed as a structure in which the vertical distance from the reflector to the beam splitter can be adjusted, thereby realizing the azimuth measurement of two laser beams with different height differences.

Specifically, when the positive mirror is used to align the laser mark, as shown in Figure 10, the laser is located above the single-component fluxgate probe. At this time, the laser beam emitted by the laser is directly incident on the centerline A of the beam splitter 4.2 , the laser beam transmitted by the beam splitter 4.2 is projected to the PSD position sensor 4.4, therefore, the PSD position sensor detects the azimuth of the laser beam emitted by the laser.

When the anti-mirror is used to align the laser mark, the horizontal axis rotates to drive the parallel bracket to rotate in the vertical plane, so that the laser is located under the single-component fluxgate probe, as shown in Figure 11. Therefore, the laser beam emitted by the laser It is incident on the reflector, after being reflected upward by the reflector, it is incident vertically to the position of the center line A of the beam splitter, and after being reflected by the beam splitter, it is incident horizontally to the PSD position sensor. Therefore, the PSD position sensor detects the laser The orientation of the emitted laser beam.

It can be seen that, through the position measuring device based on the PSD position sensor provided by the present invention, through a simple structure, the PSD sensor at the same position skillfully realizes the azimuth measurement of two incident lasers at different heights, thereby improving the measurement accuracy.

The total controller is electrically connected with the first laser reading head 2.5, the first piezoelectric motor 2.7, the second laser reading head 2.10, the second piezoelectric motor 2.12, the laser 3.2, the single-component fluxgate probe 3.3 and the electronic level sensor 3.4 connect. The general controller is connected with the marker position sensor through the data collector.

This shows that the automatic fluxgate theodolite for absolute geomagnetic observation provided by the present invention has the following advantages:

(1) The laser is used to replace the traditional markers, and the laser is used to align the markers, which can effectively ensure the accuracy of the alignment markers, thereby ensuring the measurement accuracy of the measured geomagnetic declination D and geomagnetic inclination I ;

(2) A two-dimensional non-magnetic rotating mechanism carrying a single-component fluxgate probe is designed, which can automatically and precisely realize the horizontal rotation and vertical rotation of the single-component fluxgate probe, and finally realize the geomagnetic declination D and geomagnetic inclination I automatic measurement of

(3) A marker position sensor with a special structure is designed, which can ingeniously realize the azimuth measurement of two incident lasers at different heights by the PSD sensor at the same position, thereby reducing the measurement when the front and rear mirrors are aligned with the markers errors and improve the accuracy of geomagnetic field measurement.

Those skilled in the art can understand that using the automatic fluxgate theodolite for absolute geomagnetic observation provided by the present invention, any measurement method in the prior art can be used to realize absolute geomagnetic measurement, and the present invention does not limit the specific measurement method. But, for convenience the automatic fluxgate theodolite provided by the present invention is fully understood, enumerates a kind of concrete absolute geomagnetic measuring method below, but following measuring method does not limit protection scope of the present invention:

Referring to Fig. 12, the automatic absolute geomagnetic measurement method comprises the following steps:

Step 1, arrange the absolute geomagnetic measurement mechanism at the survey point, the absolute geomagnetic measurement mechanism includes a support mechanism (1), a two-dimensional non-magnetic rotating mechanism (2) and a measurement unit (3); arrange the position of the marker at the selected position sensor; and, the vertical distance from the reflector (4.3) to the beam splitter (4.2) in the marker position sensor is the same as the vertical distance from the laser (3.2) to the single-component fluxgate probe (3.3);

During the erection process of the instrument, rotate the vertical axis, respectively at the initial zero position of the instrument and plus or minus 90 degrees, with the electronic level sensor (3.4) as a reference, by adjusting the three adjustment feet and the second piezoelectric motor (2.12), the The measurement unit (3) is leveled to ensure that the laser (3.2) and the single-component fluxgate probe (3.3) of the measurement unit (3) are on the horizontal test surface; at the same time, according to the height of the laser spot emitted by the laser (3.2) after leveling, Adjust the window height of the marker position sensor to make the two equal;

Step 2, the process of initially aligning the marker position sensor, including:

Step 2.1, arrange the laser (3.2) in parallel above the single-component fluxgate probe (3.3);

In step 2.2, the general controller turns on the laser (3.2), and at the same time, the general controller controls the first piezoelectric motor (2.7), so that the horizontal non-magnetic rotating unit rotates around the vertical axis, and the laser (3.2) emits The horizontal laser approaches the sensing window of the marker position sensor, that is, approaches the sensing window of the PSD position sensor (4.4);

In step 2.3, the master controller continues to control the horizontal non-magnetic rotating unit to rotate around the vertical axis, and makes the laser emitted by the laser incident on the edge of the sensing window of the PSD position sensor (4.4) horizontally after being transmitted by the beam splitter (4.2) , so that the data collector collects the induced voltage; then, the general controller controls the horizontal non-magnetic rotating unit to continue to rotate around the vertical axis; since the laser corresponds to different induced voltages at different positions of the sensing window of the PSD position sensor, when the data collector collects When the specified induced voltage is reached, it means that the horizontal non-magnetic rotating unit has rotated to the specified position around the vertical axis. At this time, the main controller controls the horizontal non-magnetic rotating unit to stop rotating, and the main controller obtains this information through the first laser reading head (2.5). When there is no magnetic axis frame (2.1), the exact azimuth angle is denoted as N ₁ , thus completing the calibration mirror measurement;

Step 2.4, then, the general controller controls the second piezoelectric motor (2.12), thereby driving the horizontal axis (2.8) to rotate 180°, and then driving the measuring unit (3) to rotate 180°, so that the laser (3.2) is arranged in parallel on Below the single-component fluxgate probe (3.3), then lock the second piezoelectric motor (2.12);

Step 2.5, then, the general controller controls the first piezoelectric motor (2.7) again, so that the horizontal non-magnetic rotating unit rotates around the vertical axis, and the horizontal laser emitted by the laser (3.2) passes through the mirror (4.3) After the upward reflection and the reflection of the beam splitter (4.2), it is incident on the edge of the sensing window of the PSD position sensor (4.4), so that the data collector collects the induced voltage; then, the master controller controls the horizontal non-magnetic rotation The unit continues to rotate around the vertical axis; since the laser corresponds to different induced voltages at different positions of the sensing window of the PSD position sensor, when the data collector collects the specified induced voltage, it means that the horizontal non-magnetic rotating unit has rotated around the vertical axis to the specified position. At this time, the main controller controls the horizontal non-magnetic rotating unit to stop rotating, and the main controller obtains the precise azimuth of the non-magnetic axis frame (2.1) at this time through the first laser reading head (2.5), which is recorded as N ₂ , thus completing Benchmark mirror measurement;

Step 2.6, the general controller averages _N1 and _N2 to obtain the sign reading N;

Due to the existence of machining and assembly errors, there will be a small non-orthogonal angle μ between the laser axis and the horizontal axis of the automatic fluxgate theodolite. The purpose of the laser emitted by the laser is to calculate the reading of geographic north on the horizontal code disk by aiming at the marker. If only the positive mirror or the reverse mirror is used to align the marker once, due to the existence of the non-orthogonal angle μ, the marker angle obtained by the automatic fluxgate theodolite will introduce errors. However, if the method of measuring the positive and negative mirrors is adopted, since the positive and negative mirrors bring positive and negative errors respectively, the two readings are added to get the average value, and the positive and negative errors can be offset, that is to say, the non-orthogonal degree μ band The resulting errors can be effectively offset.

Step 3, the step of measuring the geomagnetic declination D , includes:

Step 3.1, the master controller turns off the laser (3.2), and turns on the single-component fluxgate probe (3.3). At this time, the laser (3.2) is arranged in parallel under the single-component fluxgate probe (3.3);

Step 3.2, the general controller controls the horizontal non-magnetic rotating unit to rotate around the vertical axis. At the same time, the general controller judges in real time whether the external magnetic field strength signal output by the single-component fluxgate probe (3.3) is 0. The device obtains the angle value D ₁ of the first measurement position of the geomagnetic declination with zero value of the external magnetic field through the first laser reading head (2.5);

Then, the master controller controls the horizontal non-magnetic rotating unit to reversely rotate around the vertical axis. The controller obtains the angle value D ₂ of the second measurement position of the geomagnetic declination with zero value of the external magnetic field through the first laser reading head (2.5);

Step 3.3, then, the general controller controls the second piezoelectric motor (2.12), thereby driving the horizontal axis (2.8) to rotate 180°, and then driving the measuring unit (3) to rotate 180°, so that the laser (3.2) is arranged in parallel on Above the single-component fluxgate probe (3.3), then lock the second piezoelectric motor (2.12);

Step 3.4, then, the general controller controls the horizontal non-magnetic rotating unit to rotate around the vertical axis. At the same time, the general controller judges in real time whether the external magnetic field strength signal output by the single-component fluxgate probe (3.3) is 0. When it reaches 0, The master controller obtains the angle value D ₃ of the third measurement position of the geomagnetic declination with zero value of the external magnetic field through the first laser reading head (2.5);

Then, the master controller controls the horizontal non-magnetic rotating unit to reversely rotate around the vertical axis. The controller obtains the angle value D ₄ of the fourth measurement position of the geomagnetic declination with zero value of the external magnetic field through the first laser reading head (2.5);

Step 3.5, the angle value D ₁ of the first measurement position of geomagnetic declination, the angle value D ₂ of the second measurement position of geomagnetic declination, the angle value D 3 of the third measurement position of geomagnetic declination, and the angle value D ₃ of the fourth measurement position of geomagnetic declination Calculate the mean value of the angle value D ₄ , which is the geomagnetic north reading D ₀ ;

Calculate the actual magnetic declination D according to the following formula:

Actual magnetic declination D = geomagnetic north reading D ₀ - geographic north direction reading = geomagnetic north reading D ₀ - (sign reading N-mark azimuth);

Among them, the azimuth of the marker is measured in advance by the geomagnetic station, that is, the angle between the geographic north and the marker with the measurement point as the center of the circle;

Referring to Figure 12, the reference of the geomagnetic north reading D ₀ is the zero point of the automatic fluxgate theodolite instrument, as shown in ∠A2 in the figure;

The reference of the mark reading N is the zero point of the automatic fluxgate theodolite instrument, as shown in ∠A1 in the figure, the consistency of the angle alignment is mainly used to ensure whether the instrument is displaced during multiple measurement processes or during placement;

The reference of the actual magnetic declination D is geographic north, as shown in ∠A4 in the figure.

Step 4, the measuring step of geomagnetic inclination I , comprises:

Step 4.1, the laser (3.2) is arranged in parallel above the single-component fluxgate probe (3.3), and the total controller controls the horizontal non-magnetic rotating unit to rotate around the vertical axis to the position of the geomagnetic north reading D ₀ ; at this time, the single-component magnetic flux The door probe (3.3) is located in the magnetic meridian;

Then, the vertical axis is locked and no longer rotates; the master controller controls the second piezoelectric motor (2.12), thereby driving the horizontal axis (2.8) to rotate, and the horizontal axis (2.8) drives the laser (3.2) and The single-component fluxgate probe (3.3) rotates synchronously in the magnetic meridian; at the same time, the total controller judges in real time whether the external magnetic field strength signal measured by the single-component fluxgate probe (3.3) is 0, and when it reaches 0, the total The controller obtains the angle value I ₁ of the first measurement position of the geomagnetic inclination angle with zero value of the external magnetic field through the second laser reading head (2.10);

Then, the general controller continues to control the horizontal axis to rotate in the opposite direction. When the fluxgate probe measures the signal of the external magnetic field strength to be 0 again, the general controller obtains the 0 value of the external magnetic field through the second laser reading head (2.10). 2. The angle value I ₂ of the measurement position;

Step 4.2, next, the general controller controls the rotation of the vertical axis, so that the vertical axis stops at D ₀ position + 180° or D ₀ position -180°;

Then, lock the vertical axis no longer rotate;

The general controller controls the second piezoelectric motor (2.12), thereby driving the horizontal axis (2.8) to rotate, and the horizontal axis (2.8) drives the laser (3.2) and the single-component fluxgate probe (3.3) through the parallel bracket (3.1) It rotates synchronously with the electronic level sensor (3.4) in the magnetic meridian plane; at the same time, the total controller judges in real time whether the external magnetic field strength signal measured by the single-component fluxgate probe (3.3) is 0, and when it reaches 0, the total controller Through the second laser reading head (2.10), the angle value I ₃ of the third measurement position of the geomagnetic inclination with zero value of the external magnetic field is obtained;

In step 4.3, the general controller continues to control the horizontal axis to rotate in the opposite direction. When the single-component fluxgate probe (3.3) measures the signal of the external magnetic field strength to be 0 again, the general controller obtains the external magnetic field strength signal through the second laser reading head (2.10). The angle value I ₄ of the fourth measurement position of the geomagnetic inclination angle of magnetic field zero;

In step 4.4, the magnetic inclination I is obtained based on the following formula:

Magnetic dip angle I = (I ₁ +I ₂ -I ₃ -I ₄ )/4.

The automatic absolute geomagnetic measurement method provided by the present invention has the following advantages:

(1) The laser is used to align the markers, which can effectively ensure the accuracy of the markers, so as to ensure the absolute geomagnetic measurement accuracy;

(2) The two-dimensional non-magnetic rotating mechanism is used as the driving motion mechanism of the fluxgate probe, which can automatically realize the horizontal rotation and vertical rotation of the single-component fluxgate probe with high precision, and finally ensure the absolute geomagnetic measurement accuracy;

(3) In the process of absolute geomagnetic measurement, the same marker position sensor is used to cleverly realize the azimuth measurement of two incident lasers at different heights, thereby reducing the measurement error when the front and rear mirrors are aligned with the markers, and improving the geomagnetic field measurement. precision.

The above is only a preferred embodiment of the present invention, it should be pointed out that, for those of ordinary skill in the art, without departing from the principle of the present invention, some improvements and modifications can also be made, and these improvements and modifications can also be made. It should be regarded as the protection scope of the present invention.

Claims (3)

1. An automatic fluxgate theodolite for absolute geomagnetic observation, characterized in that it comprises: a support mechanism (1), a two-dimensional non-magnetic rotating mechanism (2), a measuring unit (3) and a total controller; Wherein, the support mechanism (1) includes an upper panel (1.1), a lower panel (1.2) and a column (1.3); the upper panel (1.1) and the lower panel (1.2) are horizontally arranged symmetrically up and down; the column The number of (1.3) is at least two, fixedly installed between the upper panel (1.1) and the lower panel (1.2); The two-dimensional non-magnetic rotating mechanism (2) includes a horizontal non-magnetic rotating unit and a vertical non-magnetic rotating unit; the horizontal non-magnetic rotating unit is used to rotate the measuring unit (3) in the horizontal space, including: Magnetic axis frame (2.1), first vertical axis (2.2), second vertical axis (2.3), first circular grating code disc (2.4), first laser reading head (2.5), first piezoelectric ceramic ring (2.6 ) and the first piezoelectric motor (2.7); The non-magnetic shaft frame (2.1) is vertically arranged, and the bottom center and top center of the non-magnetic shaft frame (2.1) are respectively fixedly installed with the first vertical shaft (2.2) and the second vertical shaft (2.3); Wherein, the bottom of the first vertical shaft (2.2) is rotatably mounted on the center of the lower panel (1.2) through a bearing; the first piezoelectric ceramic ring (2.6) is located at the center of the lower panel (1.2) above, and the center of the first piezoelectric ceramic ring (2.6) is fixedly sleeved on the second vertical shaft (2.3), and the first piezoelectric motor (2.7) is fixedly installed on the lower panel ( 1.2), and the output end of the first piezoelectric motor (2.7) is in close contact with the surface of the first piezoelectric ceramic ring (2.6), and the first piezoelectric motor (2.7) passes through the The first piezoelectric ceramic ring (2.6) drives the second vertical shaft (2.3) to rotate in the horizontal space, and then drives the non-magnetic shaft frame (2.1) to rotate in the horizontal space; the second vertical shaft ( The top of 2.3) is rotatably mounted on the center of the upper panel (1.1) through a bearing and extends above the upper panel (1.1); the first circular grating code disc (2.4) is located on the upper panel ( 1.1), and the center of the first circular grating code wheel (2.4) is fixedly connected to the second vertical axis (2.3), and the first laser reading head (2.5) is connected to the first circular grating The code wheel (2.4) is connected to read the rotation angle value measured by the first circular grating code wheel (2.4); The vertical non-magnetic rotating unit includes a horizontal axis (2.8), a second circular grating code disc (2.9), a second laser reading head (2.10), a second piezoelectric ceramic ring (2.11) and a second piezoelectric motor (2.12 ); the horizontal shaft (2.8) is arranged horizontally between the left side beam and the right side side beam of the non-magnetic shaft frame (2.1), and the right end of the horizontal shaft (2.8) is rotatably mounted through a bearing At the center of the right side beam; the second piezoelectric ceramic ring (2.11) is located inside the right side beam, and the center of the second piezoelectric ceramic ring (2.11) is fixedly sleeved on the At the right end of the horizontal shaft (2.8), the second piezoelectric motor (2.12) is fixedly installed on the inner side of the right longitudinal beam, and the output end of the second piezoelectric motor (2.12) is connected to the The surface of the second piezoelectric ceramic ring (2.11) is in close contact, and the second piezoelectric motor (2.12) drives the horizontal axis (2.8) to rotate in the vertical space through the second piezoelectric ceramic ring (2.11); The left end of the horizontal shaft (2.8) is rotatably mounted on the center of the left longitudinal beam through a bearing and extends to the outside of the left longitudinal beam; the second circular grating code disc (2.9) is located on the The outside of the left longitudinal beam, and the center of the second circular grating code disc (2.9) is fixedly connected to the left end of the horizontal axis (2.8), and the second laser reading head (2.10) is connected to the second The circular grating code wheel (2.9) is connected to read the rotation angle value measured by the second circular grating code wheel (2.9); The measuring unit (3) includes: a parallel support (3.1), a laser (3.2), a single-component fluxgate probe (3.3) and an electronic level sensor (3.4); the geometric center of the parallel support (3.1) is provided with a The mounting holes matching the horizontal shafts (2.8); the parallel brackets (3.1) are fixedly installed in the center of the horizontal shafts (2.8) through the mounting holes; the upper and lower ends of the parallel brackets (3.1) are respectively installed The laser (3.2) and the single-component fluxgate probe (3.3); the laser (3.2) and the single-component fluxgate probe (3.3) are arranged in parallel; the sides of the parallel bracket (3.1) are fixed installing said electronic level sensor (3.4); The general controller is respectively connected with the first laser reading head (2.5), the first piezoelectric motor (2.7), the second laser reading head (2.10), and the second piezoelectric motor (2.12) , the laser (3.2), the single-component fluxgate probe (3.3) and the electronic level sensor (3.4) are electrically connected; Wherein, the support mechanism (1) also includes adjustment screws (1.4); the number of the adjustment screws (1.4) is 3, fixedly installed at the bottom of the lower panel (1.2) at equal intervals; Wherein, it also includes: a marker position sensor and a data collector; the marker position sensor is connected to the general controller through the data collector. 2. The automated fluxgate theodolite for absolute geomagnetic observation according to claim 1, characterized in that the marker position sensor is a position measurement device based on a PSD sensor, comprising an outer shell (4.1), a beam splitter (4.2), mirror (4.3) and PSD position sensor (4.4); The outer shell (4.1) is a cavity structure with an open front; the beam splitter (4.2) is obliquely fixed inside the outer shell (4.1), and the splitting surface of the beam splitter (4.2) and The axis forms an included angle of 45 degrees; the centerline of the splitting surface of the beam splitter (4.2) is the centerline A, and the centerline A communicates with the front opening of the outer casing (4.1); in the outer casing (4.1) The inner wall of the rear end of the beam splitter (4.2) is located on the transmitted light path passing through the center line A, and the PSD position sensor (4.4) is fixedly installed; The reflection mirror (4.3) is obliquely fixed to the bottom wall of the outer housing (4.1), the reflection surface of the reflection mirror (4.3) is arranged parallel to the beam splitting surface of the beam splitter (4.2), and the The centerline of the reflective surface of the reflector (4.3) is the centerline B, and the centerline B is located directly below the centerline A. Therefore, the laser incident horizontally on the centerline B of the reflector (4.3) goes upward through the reflector (4.3) After reflection, it is incident vertically to the position of the center line A of the beam splitter (4.2), and after being reflected by the beam splitter (4.2), it is horizontally incident to the PSD position sensor (4.4) and detected by the PSD position sensor (4.4) The initial orientation of the incident laser in the horizontal plane. 3. The automated fluxgate theodolite for absolute geomagnetic observation according to claim 2, characterized in that the vertical distance from the reflector (4.3) to the beam splitter (4.2) is adjustable; It also includes a beam splitter support frame (4.6); the beam splitter (4.2) is fixed to the inner cavity of the outer casing (4.1) through the beam splitter support frame (4.6); A light transmission hole (4.7) is opened on the top of the outer housing (4.1) and on the reflected light path of the beam splitter (4.2) passing through the central line A.

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