CN103292795B - A method for accurate measurement by using dual prisms, and a measuring rod - Google Patents
A method for accurate measurement by using dual prisms, and a measuring rod Download PDFInfo
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- CN103292795B CN103292795B CN201310109586.0A CN201310109586A CN103292795B CN 103292795 B CN103292795 B CN 103292795B CN 201310109586 A CN201310109586 A CN 201310109586A CN 103292795 B CN103292795 B CN 103292795B
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Abstract
The invention provides a method and an apparatus for accurate measurement by using dual prisms. The method comprises: measuring prism A, prism B and a to-be-measured point C which are located on the same line; in the case that a linear distance SBC between the prism B and the to-be-measured point C is given, determining three-dimensional coordinates of the prism A (XA, YA, HA), and the prism B (XB, YB, HB); and measuring and calculating a slope distance SAB between the prism A and the prism B and a slope distance SBC between the prism A and the to-be-measured point C, and calculating the three-dimensional coordinates of the to-be-measured point C according to a formula (shown in the specification). According to the present invention, the method is simple, the accuracy is high, during the measurement, the need of adjusting an adjustment bubble of a measuring rod is eliminated; during measurement of a sheltered position, all one need to do is to adjust the angle direction of the measuring rod or lengthen the distance between the prism B and the to-be-measured point C according to the situation, without the need of side shots.
Description
Technical field
The present invention relates to a kind of method, particularly the method and apparatus accurately measured of a kind of biprism.
Background technology
The common single prism occurred on the market is measured centering rod and is had the small and exquisite feature such as flexible, simple to operate, be widely used in mapping operations field, its drawback is exactly that the round leveling bubble of centering rod can only check vertical roughly, the measuring point be suitable for also can only be the vertical of position, measured point, and other non-vertical concealment parts then cannot be measured.Sometimes the stability in order to improve vertical centering needs to increase tripod; thus add equipment cost; carry also inconvenient; and owing to colliding with or shaking and other reasons in actual mapping process; the round leveling bubble precision of centering rod often can be caused low; when occurring that bubble is placed in the middle, centering rod is actual is the phenomenon tilted, and causes the gross error of range finding and angle measurement, affects the precision of measurement point position.Common centering rod needs often to carry out strict check, and during to ensure that round leveling bubble on centering rod is placed in the middle, centering rod keeps vertically.Also very high to the requirement of auxiliary department mirror personnel during measurement, requirement department mirror personnel significant attention, strict continuing keeps bubble placed in the middle, and bubble slightly deviation will cause larger measuring error, cannot ensure high precision and the accuracy of Point Measurement.
Summary of the invention
The object of this invention is to provide a kind of position being widely used in common centering rod and measuring, be more suitable for the concealment part that common centering rod cannot be measured, the position cannot directly measured when the setting-out position, face big gun hole be blocked as sight line in underground cavern excavation process, concrete placings surveying and locating and template are checked and accepted, Metal structure installation and privileged sites when detecting, vertical is blocked cannot the measuring point etc. of vertical centering.
Technical scheme of the present invention is achieved in that the method that biprism is accurately measured comprises the A prism, B prism and the C tested point that are located on the same line with total station survey, air line distance S between B prism and C tested point
bCwhen known, go out the three-dimensional coordinate of A prism, B prism with total station survey, A prism (XA, YA, HA), B prism (XB, YB, HB), and calculate the oblique distance S of A prism to B prism
aBand B prism is to the oblique distance S of C tested point
bC, use following formulae discovery to go out the three-dimensional coordinate of C tested point, concrete formula comprises the following steps:
(1) the horizontal projection distance D of A prism, B prism, is calculated
aB
The horizontal projection distance D of A prism, B prism
aBby planimetric coordinates (XA, YB), the calculating of (XB, YB) inverse of A prism, B prism.Computing formula is:
;
The horizontal projection distance D of B prism, C tested point
bCby the oblique distance S of A prism to B prism
aBand B prism is to the oblique distance S of C tested point
bCcalculate according to vertical similar triangle theory, S
aB/ D
aB=S
bC/ D
bC, D
bC=S
bC/ S
aB* D
aB;
(2) projection coordinate (XC, YC) of C tested point in plane coordinate system is calculated
(XB-XC)/D
bC=(XA-XB)/D
aB, then XC=XB-D
bC/ D
aB* (XA-XB), if it is equal with the distance to A prism to C tested point to be positioned at B prism, i.e. S
aB=S
bC, then XC=2XB-XA, (XC+XA)/2=XB, i.e. mid-point formula.
In like manner: (YB-YC)/D
bC=(YA-YB)/D
aB, then YC=YB-D
bC/ D
aB* (YA-YB), if S
aB=S
bC, then YC=2YB-YA, (YC+YA)/2=YB.
(3) the elevation HC of C tested point is calculated
Measuring point elevation HC:S is calculated according to vertical similar triangle theory
aB/ (HA-HB)=S
bC/ (HB-HC), then: HC=HB-S
bC/ S
aB* (HA-HB).If S
aB=S
bC, then HC=2HB-HA, (HC+HA)/2=HB, mid-point formula.
Just the three-dimensional coordinate (XC, YC, HC) of C tested point can be calculated by above step.
For the equipment biprism hidden sounding rod that biprism is accurately measured, comprise one end and be provided with the pole of sharp body and two prisms on described pole, between each described prism, have interval.
Further, pole is made up of connecting link and the backstay with sharp body, and connecting link one end is set to female fitting, the other end is convex joint, and backstay one end is sharp body, the other end is convex joint, prism two side is respectively equipped with female fitting, convex joint, and described female fitting can coincide with convex joint and be connected.
All right, the picture frame of prism posts reflective membrane.
The invention has the advantages that, use above method, just measure air line distance S between B prism and C tested point in advance
bC, then measure A prism (XA, YA with the total powerstation building up station, HA), the three-dimensional coordinate of B prism (XB, YB, HB), namely C tested point (XC, YC, HC) can be calculated by mathematical operation, as long as its process ensures that A prism, B prism, C tested point are on same straight line, eliminate the process repeatedly adjusting bubble in the middle of centering rod, make measurement more quick, simultaneously, when C tested point be in hole or concealment part time, by lengthen S
bCdistance, A prism, B prism is placed in outside hole or concealment part can be measured outward, and what minimizing was middle draws point process, improves the precision measured, its process eliminates centering rod adjustment centering steam bubble and measures hidden point needs the process of drawing a little, only needs in conjunction with known S
bClength, then measure A prism (XA, YA, HA), B prism (XB, YB, HB), the remaining three-dimensional can obtaining C tested point (XC, YC, HC) by computing is marked, and A prism is to the oblique distance S of B prism
aBcan measure in advance, also can calculate by mathematical operation.
Use above structure, the sharp body of pole is positioned over tested point, during measurement, this centering rod can be placed arbitrarily any measurement, as long as total powerstation quick and precisely can measure the three-dimensional coordinate of two prisms, namely calculate the three-dimensional coordinate of tested point by mathematical operation.
In measuring process, except the sharp body of pole must be positioned over except on tested point, pole need not keep vertical or state, the three-dimensional coordinate of tested point can be measured, relatively traditional pole is not used for adjustment verticality centering bubble, and operate more simple, precision is also higher.
Pole is made up of connecting link and the backstay with sharp body, connecting link one end is set to female fitting, the other end is convex joint, backstay one end is sharp body, the other end is convex joint, prism two side is respectively equipped with female fitting, convex joint, described female fitting can coincide with convex joint and be connected, long fulcrum bar can be added arbitrarily as required, to adapt to the needs of varying environment.
The picture frame of prism posts reflective membrane, and when sighting, target clearly, is easy to find.
Accompanying drawing explanation
Fig. 1 is Computing Principle schematic diagram of the present invention.
Fig. 2 is that plane of the present invention makes mark Computing Principle schematic diagram.
Fig. 3 is that high standard of the present invention makes mark Computing Principle schematic diagram.
Fig. 4 is present device structural representation.
Fig. 5 is present device connecting link schematic diagram.
Fig. 6 is present device backstay schematic diagram.
Fig. 7 is present device prism schematic diagram.
As schemed S
aBfor S-AB, D
aBfor D-AB, S
bCfor S-BC
,d
bCfor D-BC pole 1, prism 2, connecting link 3, backstay 4.
Embodiment
Composition graphs 1, Fig. 2, Fig. 3, measuring method is that the method that biprism is accurately measured comprises the A prism, B prism and the C tested point that are located on the same line with total station survey, air line distance S between B prism and C tested point
bCwhen known, go out the three-dimensional coordinate of A prism, B prism with total station survey, A prism (XA, YA, HA), B prism (XB, YB, HB), and calculate the oblique distance S of A prism to B prism
aBand B prism is to the oblique distance S of C tested point
bC, use following formulae discovery to go out the three-dimensional coordinate of C tested point, concrete formula comprises the following steps:
(1) the horizontal projection distance D of A prism, B prism, is calculated
aB
The horizontal projection distance D of A prism, B prism
aBby planimetric coordinates (XA, YB), the calculating of (XB, YB) inverse of A prism, B prism.Computing formula is:
;
The horizontal projection distance D of B prism, C tested point
bCby the oblique distance S of A prism to B prism
aBand B prism is to the oblique distance S of C tested point
bCcalculate according to vertical similar triangle theory, S
aB/ D
aB=S
bC/ D
bC, D
bC=S
bC/ S
aB* D
aB;
(2) projection coordinate (XC, YC) of C tested point in plane coordinate system is calculated
(XB-XC)/D
bC=(XA-XB)/D
aB, then XC=XB-D
bC/ D
aB* (XA-XB), if it is equal with the distance to A prism to C tested point to be positioned at B prism, i.e. S
aB=S
bC, then XC=2XB-XA, (XC+XA)/2=XB, i.e. mid-point formula.
In like manner: (YB-YC)/D
bC=(YA-YB)/D
aB, then YC=YB-D
bC/ D
aB* (YA-YB), if S
aB=S
bC, then YC=2YB-YA, (YC+YA)/2=YB.
(3) the elevation HC of C tested point is calculated
Measuring point elevation HC:S is calculated according to vertical similar triangle theory
aB/ (HA-HB)=S
bC/ (HB-HC), then: HC=HB-S
bC/ S
aB* (HA-HB).If S
aB=S
bC, then HC=2HB-HA, (HC+HA)/2=HB, mid-point formula.
Just the three-dimensional coordinate (XC, YC, HC) of C tested point can be calculated by above step.
Composition graphs 4, Fig. 5, Fig. 6, Fig. 7, equipment biprism hidden sounding rod for biprism accurate measurement method comprises the pole 1 that one end is provided with sharp body, and two prisms 2 on described pole 1 are respectively the A prism in measuring method, B prism, pole 1 is by two connecting links 3, and the backstay 4 with sharp body forms, connecting link 3 one end is set to female fitting, the other end is convex joint, backstay 4 one end is sharp body, the other end is convex joint, prism 2 two side is respectively equipped with female fitting, convex joint, the convex joint of the female fitting of one of them prism 2 with backstay 4 is connected, prism 2 convex joint connects with the female fitting of a wherein connecting link 3, the female fitting of another prism 2 connects with its convex joint, the convex joint of another prism can also connect the female fitting of another connecting link 3, the picture frame of prism 2 posts reflective membrane.
Principle of work: during work, first build up total powerstation workstation by General Requirements, the sharp body of pole 1 is positioned over C tested point, this centering rod any measurement be can be placed arbitrarily during measurement, and A prism (XA, YA quick and precisely can be measured with total powerstation, HA), B prism (XB, the three-dimensional coordinate of YB, HB, because A prism is to the oblique distance S of B prism
aBand B prism is to the oblique distance S of C tested point
bCbe relatively-stationary, can measure by prior survey instrument, such as tape measure or Steel Ruler.
Contrast test is as follows:
1, total powerstation is adopted to measure in conjunction with common single prism centering rod
In working-yard, building site, Three Gorges, when Setting Station of Total Station Instrument checks complete, common single prism centering rod is adopted to measure certain any three-dimensional coordinate, by centering rod bottom alignment measuring point C, keep the round leveling bubble on centering rod placed in the middle, total powerstation sights common centering rod, and (height bottom prism centers to centering rod is 1.3m, unit is m, as follows) above single prism centers, the three-dimensional coordinate of three groups of list prism centers is recorded by total powerstation, draw after average: X=21458.266, Y=48122.732, H=96.349.Assuming that bubble is strictly placed in the middle when measuring, the perpendicularity deviation of prism bar is ignored, then the planimetric coordinates of measuring point is the projection coordinate (XC=21458.266, YC=48122.732) of prism centers, and the elevation of measuring point is HC=96.349-1.3=95.049.
2, total powerstation is adopted to measure in conjunction with biprism hidden sounding rod
(1) (namely B point is on the mid point of AC line segment, S for the equidistant situation bottom prism B to prism A and prism B to sounding rod
aB=S
bC).
When adopting biprism hidden sounding rod to measure, setting top prism is A prism, lower prism is B prism, and measuring point is the center distance S of C, AB two prisms
aBfor boring the interval S of point bottom 0.4m, B prism centers to sounding rod
bCfor 0.4m, do not need the leveling bubble on sounding rod placed in the middle when total powerstation is observed, as long as keep stable during sounding rod bottom alignment measuring point, can arbitrarily angledly place, total powerstation sights two A prisms, B prism on centering rod, the three-dimensional coordinate that Quick Measuring obtains A prism centers is (XA=21458.133, YA=48122.832, HA=95.830), the three-dimensional coordinate of B prism centers is (XB=21458.200, YB=48122.781, HB=95.439).Then according to above-mentioned mid-point formula:
XC=2XB-XA=21458.267,
YC=2YB-YA=48122.730,
HC=2HB-HA=95.048。
Differ respectively (0.001 ,-0.002 ,-0.001) with the common centering rod measurement result of single prism, measurement result closely.
(2) the unequal situation of distance (the i.e. S bottom prism B to prism A and prism B to sounding rod
aB≠ S
bC).
The center distance S of AB two prisms
aBa connecting link is increased, its spacing S for boring bottom 0.4m, B prism centers to sounding rod between point
bCfor 0.7m, total powerstation records the three-dimensional coordinate of A prism centers for (XA=21458.121, YA=48122.871, HA=96.128), and the three-dimensional coordinate of B prism centers is (XB=21458.173, YB=48122.821, HB=95.736).Then as follows according to above-mentioned computing formula result of calculation:
= 0.072 ,
D
BC= S
BC/ S
AB* D
AB=0.7/0.4*0.072=0.126,
XC= XB-D
BC/ D
AB*(XA-XB)= 21458.264
YC= YB-D
BC/ D
AB*(YA-YB)= 48122.734
HC=HB-S
BC/ S
AB*(HA-HB)= 95.050
Differ respectively (-0.002,0.002,0.001) with the common centering rod measurement result of single prism, measurement result closely.
Can increase according to different geographical location circumstances or shorten the oblique distance S of A prism to B prism
aBand/or B prism is to the oblique distance S of C tested point
bC, its computation process repeats above step.
Claims (1)
1. the method accurately measured of biprism, is characterized in that: the method that described biprism is accurately measured comprises the A prism, B prism and the C tested point that are located on the same line with total station survey, air line distance S between B prism and C tested point
bCwhen known, go out the three-dimensional coordinate of A prism, B prism with total station survey, A prism (XA, YA, HA), B prism (XB, YB, HB), and calculate the oblique distance S of A prism to B prism
aB, B prism is to the oblique distance S of C tested point
bC, use following formulae discovery to go out the three-dimensional coordinate of C tested point, concrete formula comprises the following steps:
(1) the horizontal projection distance D of A prism, B prism, is calculated
aB
The horizontal projection distance D of A prism, B prism
aBby planimetric coordinates (XA, YB), the calculating of (XB, YB) inverse of A prism, B prism;
Computing formula is:
;
The horizontal projection distance D of B prism, C tested point
bCby the oblique distance S of A prism to B prism
aBand B prism is to the oblique distance S of C tested point
bCcalculate according to vertical similar triangle theory, S
aB/ D
aB=S
bC/ D
bC, D
bC=S
bC/ S
aB* D
aB;
(2) projection coordinate (XC, YC) of C tested point in plane coordinate system is calculated
(XB-XC)/D
bC=(XA-XB)/D
aB, then XC=XB-D
bC/ D
aB* (XA-XB), if it is equal with the distance to A prism to C tested point to be positioned at B prism, i.e. S
aB=S
bC, then XC=2XB-XA, (XC+XA)/2=XB, i.e. mid-point formula;
In like manner: (YB-YC)/D
bC=(YA-YB)/D
aB, then YC=YB-D
bC/ D
aB* (YA-YB), if S
aB=S
bC, then YC=2YB-YA, (YC+YA)/2=YB;
(3) the elevation HC of C tested point is calculated
Measuring point elevation HC:S is calculated according to vertical similar triangle theory
aB/ (HA-HB)=S
bC/ (HB-HC), then: HC=HB-S
bC/ S
aB* (HA-HB);
If S
aB=S
bC, then HC=2HB-HA, (HC+HA)/2=HB, mid-point formula;
Just the three-dimensional coordinate (XC, YC, HC) of C tested point can be calculated by above step.
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