1. A total station centering error measuring method is applied to a total station centering error measuring system, and is characterized in that the total station centering error measuring system comprises: the total station comprises a total station, two prisms and a foot rest used for supporting the total station and the prisms;

the method for measuring the centering error of the total station comprises the following steps:

s1, lofting on a straight line by using the total station to obtain A, P points and B points, and recording the distances of PA and PB as S respectively₁、S₂；

S2, erecting the total station on a point P, erecting two prisms on a point A, B, centering and leveling, and so onThe point in the actual alignment of the total station is a point P'; acquiring observation data: alpha is < AP 'B, and the distances of P' A, P 'B are S'₁、S′₂；

And S3, calculating the centering error of the total station through an indirect adjustment algorithm based on the observation data.

2. The method for determining centering error of a total station as claimed in claim 1, wherein step S3 specifically includes:

s31, establishing a plane rectangular coordinate system with P as the origin, the linear APB direction as the Y axis and the direction perpendicular to the linear as the X axis, and then the coordinates of the point A are (0, -S)₁) P point coordinate (X)_P，Y_P) Is (0, 0), and the coordinates of the point B are (0, S)₂)；

S32, calculating P' point approximate coordinate (X) based on the observation data⁰，Y⁰) Wherein Therefore, it is

S33, constructing an error equation:

in the formula, b is the coefficient of the error equation,

wherein the content of the first and second substances, andrespectively, P' point outline coordinates (X)⁰，Y⁰) The number of corrections of (a); l is a free term of an error equation,

s34, constructing a normal equation according to the error equation, and calculating to obtain a correction numberAnd

taking the error in the angle measurement as the error in the unit weight observation value, then the weight arrayWherein sigma_α、σ_SRespectively an error in angle measurement and an error in distance measurement;

s35, correcting according to the numberAndcalculating to obtain the coordinate of P' point after adjustmentWherein

S36, calculating to obtain centering error of the total station according to the coordinates after P' point adjustment

3. The total station centering error determination method of claim 1, further comprising, after step S2:

keeping the P-point foot stand still, rotating the total station base by 120 degrees along the fixed direction, and acquiring a second group of observation data;

and continuously rotating the total station base by 120 degrees along the fixed direction to obtain a third group of observation data.

4. The total station centering error determination method of claim 3, further comprising, after step S3:

and respectively calculating to obtain other two groups of centering errors of the total station based on the second group of observation data and the third group of observation data, and averaging the three groups of centering errors to obtain the final centering error.

5. The total station centering error determination method of claim 1, wherein in step S1, A, P and B are equidistant lofting, and PA and PB are equidistant to eliminate i-angle error.

6. The method for determining centering error of total station of claim 1, wherein in step S2, said method for obtaining observation data is a method of measuring back to eliminate 2C error.

Background

The total station is widely applied to the production engineering fields of high-speed rails, tunnels, bridges, subways and the like. When conducting wire measurement, construction lofting and other work are carried out, a large number of total stations are needed for centering operation, severe environments are accompanied in tunnels and mountainous areas, light is insufficient, visibility is poor, and observation conditions are greatly influenced by terrain, so that influences of centering errors of the total stations on angle measurement accuracy cannot be ignored.

The total station laser centering device is arranged in the vertical axis of the instrument, and the centering error of the total station laser centering device is caused by the deviation of the relative position of the laser centering device and the vertical axis. The traditional method for checking the alignment error of the instrument is to rotate the instrument by 360 degrees on a bright and flat horizontal plane by using an observation method to observe the displacement of a laser point. Practice and research show that the method mainly has the following factors to influence the measurement accuracy of the centering error: firstly, the laser spot has a diameter, the higher the instrument is erected, the larger the diameter is, and the less obvious the laser spot displacement is when the instrument rotates. Secondly, the displacement cannot be accurately estimated by observing with naked eyes, the visual judgment standards of different personnel cannot be guaranteed to be consistent, the subjective factor influence is large, and the result precision is difficult to guarantee.

The total station is widely applied to engineering measurement, but the research on a method for accurately measuring the centering error is less.

Disclosure of Invention

The invention aims to provide a total station centering error measuring method and how to correct the centering error in field actual measurement by utilizing the advantages of high angle measurement and distance measurement accuracy of the total station and overcoming the defect of low centering error measurement accuracy of the existing method.

The method is suitable for instrument calibration before total station measurement.

In order to achieve the above object, the present invention provides a total station centering error measurement method, which is applied to a total station centering error measurement system, and the total station centering error measurement system includes: the total station comprises a total station, two prisms and a foot rest used for supporting the total station and the prisms;

the method for measuring the centering error of the total station comprises the following steps:

s1, lofting on a straight line by using a total station to obtain A, P points and B points, and recording the distances of PA and PB as S respectively₁、S₂；

S2, erecting a total station on the point P, erecting two prisms on A, B, and tightly erectingGrid centering and leveling, wherein the actual centering point of the total station is a point P'; observing and recording observation data: alpha is < AP 'B, and the distances of P' A, P 'B are S'₁、S′₂；

And S3, calculating the centering error of the total station through an indirect adjustment algorithm based on the observation data.

Preferably, step S3 specifically includes:

s31, establishing a plane rectangular coordinate system with P as the origin, the linear APB direction as the Y axis and the direction perpendicular to the linear as the X axis, and then the coordinates of the point A are (0, -S)₁) P point coordinate (X)_P，Y_P) Is (0, 0), and the coordinates of the point B are (0, S)₂)；

S32, calculating P' point outline coordinate (X) based on the observation data⁰，Y⁰) Wherein Therefore, it is

S33, constructing an error equation:

in the formula, b is the coefficient of the error equation,where ρ ″ ═ 206265;whereinAndrespectively, P' point outline coordinates (X)⁰，Y⁰) The number of corrections of (a); l is a free term of an error equation,

s34, constructing a normal equation according to the error equation, and calculating to obtain a correction number

Taking the error in the angle measurement as the error in the unit weight observation value, then the weight arrayWherein sigma_α、σ_SRespectively obtaining an angle measurement error and a distance measurement error, and actually taking values according to the angle measurement accuracy and the distance measurement accuracy of the total station to be detected;

s35, correcting according to the numberAndcalculating to obtain the coordinate of P' point after adjustmentWherein

S36, calculating to obtain centering error of the total station according to the coordinates after P' point adjustment

Preferably, after step S2, the method further includes:

keeping the P-point foot stand still, rotating the total station base by 120 degrees along the fixed direction, and observing and recording a second group of observation data;

and continuously rotating the base of the total station by 120 degrees along the fixed direction, and observing and recording a third group of observation data.

Preferably, after step S3, the method further includes:

and respectively calculating to obtain other two groups of centering errors of the total station based on the second group of observation data and the third group of observation data, and averaging the three groups of centering errors to obtain a final centering error.

Preferably, in step S1, A, P and B are equidistant lofting, and PA and PB are equidistant to eliminate i-angle error.

Preferably, in step S2, the method for observing ≈ AP' B is a echo method to eliminate the 2C error.

Preferably, after the final centering error is determined, the method further comprises: comparing the final centering error with a set threshold value, and judging whether the final centering error can be directly used for actual production; and if the centering error exceeds a set threshold value, fine adjustment can be carried out on the centering position of the total station by utilizing the coordinate after the P' point adjustment obtained through calculation, so that the centering error is corrected.

The invention has the beneficial effects that:

the total station centering error measuring method provided by the invention is simple to operate and easy to realize, and has higher precision than the conventional method for observing the centering error of the instrument by naked eyes. Can inspect the total powerstation centering error in arbitrary place before field survey, discover that the error transfinites and can in time handle, avoid great because of the measuring result deviation that this error leads to, work efficiency reduces, needs a large amount of reworks scheduling problem, can provide good basis for developing of follow-up measurement work.

Drawings

The invention will be further described with reference to the accompanying drawings and examples, in which:

FIG. 1 is a diagram illustrating the steps of a centering error determination method according to an embodiment of the present invention;

fig. 2 is a schematic representation of a total station lofting in an embodiment of the invention;

fig. 3 is a schematic view of a total station in an embodiment of the present invention;

fig. 4 is a schematic diagram of measuring centering error of the total station in the embodiment of the present invention.

Detailed Description

For a more clear understanding of the technical features, objects and effects of the present invention, embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

Referring to fig. 1, in this embodiment, a method for determining a centering error of a total station is provided, including the following steps:

s1, lofting on the same straight line by using a total station to obtain A, P points and B points;

s2, erecting a total station on a point P, erecting two prisms on A, B, and performing strict centering and leveling, wherein the point in the total station which is actually centered is a point P'; observing and recording observation data: alpha is < AP 'B, and the distances of P' A, P 'B are S'₁、S′₂；

And S3, calculating the centering error of the total station through an indirect adjustment algorithm based on the observation data.

Referring to fig. 2, the total station to be detected is leveled at any position without centering, the horizontal micro-spiral is fixed, and the horizontal angle is kept unchanged. And selecting a non-prism mode, rotating the vertical micro-spiral, changing a vertical angle, and lofting three points on a straight line which is about 10m, 20m and 30m away from the total station on the ground. Then erecting prisms at the three points respectively and continuously finely adjusting until the centers of the prisms are aligned with the eyepiece cross hair, marking the position points of the three prisms as A, P, B respectively, re-measuring the distance and calculating, and using S as the distance between PA and PB₁、S₂And (4) showing.

Referring to fig. 3, a prism is erected at A, B two points, and a total station to be detected is erected at point P, and is strictly centered and leveled. At this time, due to the influence of the centering error of the laser centering device, the point actually centered by the device is the point P ', and the distance Δ from the point P' to the point P is the centering error of the total station.

Referring to fig. 3, observing an angle AP' B by a measuring method, aiming at a target A at a disk left position to obtain a reading a_{Left side of}And distance S'_{1 left side}Then aiming at target B to obtain reading B_{Left side of}And distance S'_{2 left side}If the half-angle value obtained at the left position of the disk is alpha_{Left side of}＝b_{Left side of}-a_{Left side of}(ii) a The telescope is turned to the right position of the disk and is aimed at a target B to obtain a reading B_{Right side}And distance S'_{2 right side}Aiming at target A to obtain reading a_{Right side}And distance S'_{1 right side}The disk right half return angle value is alpha_{Right side}＝b_{Right side}-a_{Right side}(ii) a And (3) averaging the left disk and the right disk to obtain observation data: reading alpha of AP 'B and distance S of P' A, P 'B'₁、S′₂。

Keeping the foot rest at the point P still, unscrewing a connecting screw of the total station and the foot rest, respectively rotating the base of the total station clockwise by 120 degrees and strictly centering and leveling after 240 degrees, and respectively continuously observing by a measuring method to obtain two groups of observation data: reading alpha of AP 'B and distance S of P' A, P 'B'₁、S′₂。

Referring to fig. 4, the step of calculating the centering error Δ through the indirect adjustment algorithm includes:

s31, establishing an independent plane rectangular coordinate system with P as the origin, the linear APB direction as the Y axis and the direction perpendicular to the linear as the X axis, wherein the coordinates of the point A are (0, -S)₁) P point coordinate (X)_P，Y_P) Is (0, 0), and the coordinates of the point B are (0, S)₂)；

S32, calculating the approximate coordinates (X) of the point P⁰，Y⁰) Wherein

S33, constructing an error equation:

in the formula, b is the coefficient of the error equation,where ρ ″ ═ 206265;whereinAndrespectively, P' point outline coordinates (X)⁰，Y⁰) The number of corrections of (a); l is a free term of an error equation,

s34, constructing a normal equation according to the error equation, and solving to obtain a correction numberAnd

taking the error in the angle measurement as the error in the unit weight observation value, then the weight arrayWherein sigma_α、σ_SAnd respectively carrying out actual value taking according to the angle measurement precision and the distance measurement precision of the total station to be detected.

S35, calculating the coordinate of P' point after adjustmentWherein

S36, calculating centering errorAnd calculating the three groups of data obtained by observation by using the above formula and calculating the average value to obtain the centering error of the total station to be detected.

And (3) judging the total station to be detected according to a total station user manual: if the centering error delta is less than or equal to 1.5mm, the centering error is within an allowable range, and the total station can be directly used for actual production; if delta is larger than 1.5mm, the total station needs to correct the centering error, and cannot be directly used for actual production.

If actual production is carried out in the field, the total station instrument alignment error is detected to be out of limit and inconvenient to return to the factory for calibration, and point position alignment correction can be carried out at the station point. According to the method provided by the invention, A, B two points are lofted on a straight line by using a total station and are respectively positioned at two sides of a measuring station (point P). Fixing the total station at a point P, centering and leveling, observing the angle and the distance between the point P ' and the point A, B with the actual centering point P ', establishing an independent plane rectangular coordinate system and leveling to obtain the coordinate of the point P ' after levelingSlightly unscrewing the connecting screw to make the total station respectively move horizontally in X-axis and Y-axis directionsThe centering error of the total station is corrected, and the next actual production can be carried out.

The total station centering error measuring method provided by the invention is simple to operate and easy to realize, and has higher precision than the conventional method for observing the centering error of the instrument by naked eyes. Can inspect the total powerstation centering error in arbitrary place before field survey, discover that the error transfinites and can in time handle, avoid great because of the measuring result deviation that this error leads to, work efficiency reduces, needs a large amount of reworks scheduling problem, can provide good basis for developing of follow-up measurement work.

It should be noted that, in this document, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or system that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or system. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other like elements in a process, method, article, or system that comprises the element.

The above-mentioned serial numbers of the embodiments of the present invention are merely for description and do not represent the merits of the embodiments. In the unit claims enumerating several means, several of these means may be embodied by one and the same item of hardware. The use of the words first, second, third and the like do not denote any order, but rather the words first, second and the like may be interpreted as indicating any order.

The above description is only a preferred embodiment of the present invention, and not intended to limit the scope of the present invention, and all modifications of equivalent structures and equivalent processes, which are made by using the contents of the present specification and the accompanying drawings, or directly or indirectly applied to other related technical fields, are included in the scope of the present invention.