JPH0914965A - Surveying target - Google Patents

Abstract

(57) [Summary] [Purpose] To provide a surveying target which can easily perform automatic collimation even at a long distance and can achieve high speed and high precision of automatic collimation. [Structure] Two diagonal lines 1 of a square target plate 13
The first mark 1 along the diagonal line 16
4a to 14d are arranged and the second along the other diagonal line 17
Marks 15a to 15d are arranged. First mark 1
Since the 4a to 14d and the second marks 15a to 15d have a predetermined width and are simple figures, the image processing is executed at high speed and the target pattern is easily extracted.
The observation accuracy by image processing is improved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a surveying target, and more particularly to a surveying target suitable for a surveying device that performs an angle measurement operation while confirming a visual field using an image sensor.

[0002]

2. Description of the Related Art FIG. 7 is a diagram showing a conventional surveying target.

As a conventional target for surveying, as shown in FIG. 7, there is one in which a cross line 200 and a circle 300 having an intersection O of the cross line 200 as a center are drawn by a thin line.

In order to perform a measurement operation using this survey target 132, the telescope of the total station is aimed at the survey target 132, and the intersection of the cross reference lines located at the center of the field of view of the telescope is set to the crosshair of the survey target 132. Match the intersection of 200. The horizontal and vertical angles of the telescope at this time are read, and the survey target 1
32 is irradiated with laser light from the total station to measure the distance to the survey target 132.

The collimation of the surveying target includes a method of collimating the surveying target with the naked eye using an eyepiece lens and a method of automatically collimating the surveying target using a CCD incorporated in the telescope.

[0006]

However, when image processing is performed using a conventional surveying target, the target pattern is composed of thin lines as described above and is a complicated figure. When the distance is long, it becomes difficult to extract the target pattern, and it takes time to perform image processing after the extraction, and the collimation accuracy is not high.

The present invention has been made in view of the above circumstances, and its object is to easily perform automatic collimation even at a long distance and to increase the speed and accuracy of automatic collimation. It is to provide a surveying target that can be measured.

[0008]

In order to solve the above-mentioned problems, a surveying target according to a first aspect of the invention has a first mark arranged along one of two imaginary lines orthogonal to each other, and A second placed along the other of the two imaginary lines
A mark, and each of the first mark and the second mark has a width suitable for image processing.

In the surveying target according to the present invention, at least two of the first marks are arranged on the one virtual line, and at least two of the second marks are arranged on the other virtual line. One of the two first marks and one of the two second marks are located inside a virtual circle centered on the intersection of the two virtual lines, and The other and the other of the two second marks are located outside the virtual circle, respectively.

In the surveying target of the third aspect of the invention, both ends of the first mark and both ends of the second mark are formed in an arc shape.

[0011]

According to the surveying target of the invention described in claim 1,
Since the first mark and the second mark forming the target pattern have a width suitable for image processing and are simple figures, the image processing is executed at high speed and the target pattern can be easily extracted.

In the surveying target of the present invention as defined in claim 2, one of the two first marks and one of the two second marks are inside a virtual circle centered on the intersection of the two virtual lines. And the second of the two first marks and the second of the two first marks.
Since the other side of the mark is located outside the virtual circle, it is possible to perform long-distance measurement and short-distance measurement, and at the time of short-distance measurement, prevent the target pattern from coming out of the image extraction area. You can

In the surveying target of the third aspect of the invention, since both ends of the first mark and both ends of the second mark are each formed in an arc shape, noise generated during thinning of image processing is reduced. Can be reduced.

[0014]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 2 is an explanatory view for explaining a measuring operation using the surveying target and the measuring device according to the first embodiment of the present invention, and FIG. 3 is a block diagram of the measuring device of FIG.

A personal computer 2 for control and operation is connected to the total station 1, and a CAD system 3 is connected to the personal computer 2.

The total station 1 includes a distance measuring unit 4, an image capturing unit 5, an image processing unit 6, an angle measuring unit (horizontal angle) 7,
It is composed of an angle measuring unit (vertical angle) 8, a CNC drive unit 9 and a CPU 10 for controlling them. The image capturing section 5 includes a telescope section and a CCD camera (not shown).

A measuring object (for example, a bridge block) 11 is arranged in front of the total station 1, and a surveying target 12 is attached to the measuring object 11.

FIG. 1 is a diagram showing a surveying target according to a first embodiment of the present invention.

As shown in FIG. 1, the surveying target 12 has a square target plate 13 and four black first marks 14a to 14 displayed on the surface of the target plate 13.
d and four black second marks 15a to 15d.

The four first marks 14a to 14d are arranged along one diagonal line 16 of the two diagonal lines (two imaginary lines orthogonal to each other) 16 of the target plate 13 and are arranged along the four second marks. The marks 15a to 15d are arranged along the other diagonal line 17 of the target plate 13. Both ends of the first marks 14a to 14d and the second marks 15a to 1
Both ends of 5d are each formed in an arc shape.

Of the four first marks 14a to 14d, the first marks 14b and 14c and the four second marks 15a to 1 are provided.
Of the 5d, the second marks 14b and 14c are located inside a virtual circle 18 centered on the intersection of the two diagonal lines 16 and 17, and the first marks 14a and 14d and the second marks 15a and 15d are , And are located outside the virtual circle 18, respectively.

The first marks 14a to 14d and the second marks 15a to 15d each have a width suitable for image processing,
In this embodiment, when one side of the target plate 13 is 50 mm, the first marks 14a-14d and the second marks 15a-
The width of 15d is 5 mm. The ratio between the width and the length (diagonal length) of the first marks 14a to 14d and the second marks 15a to 15d is 2: 5. Also, the first mark 14
The distance between a and the first mark 14b and the distance between the first mark 14c and the first mark 14d are 2.5 mm. The distance between the second mark 15a and the second mark 15b, the second mark 15c
The distance between the second mark 15d and the second mark 15d is also 2.5 mm, and a surveying target having this value is suitable for image processing.

FIG. 4 is a flow chart for explaining the procedure of automatic collimation when the surveying target of the first embodiment is used.

First, the surveying target 12 is collimated and an image is extracted (step 101). An image obtained by taking the difference between two or more images when the illumination light source for the target of the total station 1 is turned on and off is taken as an acquired image, pre-processing such as smoothing and filtering is performed, and based on a certain threshold value. And binarize. Each mark is labeled on the binarized image, and the features are calculated. In this way, the range of the survey target 12 is determined.

Since the target pattern (the shape of the entire target mark) of the surveying target 12 is composed of thick lines as described above and is a simple figure, the image processing is executed at high speed and the target pattern is extracted. It's easy.

Next, the image obtained by the image extraction, that is, the target image is subjected to image processing (step 102).
The image signal of the target image is binarized to form a binary image, the binary image is thinned, and the straight line is detected from the image signal thus processed.

As described above, the first of the surveying target 12
Both ends of the marks 14a to 14d and the second marks 15a to 15
Since both ends of d are formed in an arc shape respectively, noise generated during thinning can be reduced. For example, if both ends of the first marks 14a to 14d are angular, a simple straight line suitable for intersection detection cannot be obtained by thinning.

Finally, the coordinates of the intersection of the diagonal lines 16 and 17 are detected (step 103). The coordinates of this intersection are the coordinates of the machine point.

According to the surveying target of the first embodiment, the first marks 14a to 14c constituting the target pattern are formed.
Since 14d and the second marks 15a to 15d have a predetermined width and are simple figures, image processing is performed at high speed, target patterns are easily extracted, and observation accuracy by image processing is improved.

The target pattern has the same shape and size as the first marks 14a to 14d and the second mark 15a.
The first mark 14b, 14c and the second mark 15b, 15c are located inside the virtual circle 18 centered on the intersection of the diagonal lines 16, 17 and are divided into eight parts.
a, 14d and the second marks 15a, 15d are virtual circles 18
Since it is located outside the area, part of the mark can be prevented from coming out of the image extraction area during short-distance measurement, so noise generated during thinning can be reduced and high-precision image processing can be performed. It can be performed. Therefore, although this surveying target 12 is a single target, it can be used for both short distance measurement and long distance measurement.

Further, since both ends of the first marks 14a to 14d and both ends of the second marks 15a to 15d of the surveying target 12 are formed in an arc shape, respectively, noise generated during thinning can be reduced. You can

Further, the first marks 14a to 14d are arranged along the diagonal line, and the second marks 15a to 15d are arranged on the diagonal lines 16 and 1.
Arranged along 7 respectively, 4 for the crosshairs of the telescope
Since they are tilted by 5 °, they do not overlap in the field of view of the telescope, and image processing can be performed accurately.

Further, stable image processing is possible even if the surveying target 12 is tilted with respect to the collimation axis of the telescope.

FIG. 5 is a diagram showing a surveying target according to the second embodiment of the present invention. Portions common to the above-described embodiments are denoted by the same reference numerals, and description thereof is omitted.

The surveying target 12 of the first embodiment described above.
Then, the four first marks 14a to 14d are arranged along one of the two diagonal lines 16 and 17 which are orthogonal to each other, and the four second marks 15 are arranged along the other of the two diagonal lines 16 and 17.
Although the case of arranging a to 15d has been described, instead of this, as shown in FIG. 5, the two first marks 14c and 14c are provided.
You may make it arrange | position the d and the two 2nd marks 15c and 15d.

According to the surveying target 22 of the second embodiment, the same effect as that of the first embodiment can be obtained.

FIG. 6 is a diagram showing a surveying target according to the third embodiment of the present invention. Portions common to the above-described embodiments are denoted by the same reference numerals, and description thereof is omitted.

In the third embodiment, as shown in FIG.
You may make it arrange | position one 1st mark 14c and one 2nd mark 15c.

The surveying target 32 of the third embodiment can be used as a target for short-distance measurement.

As a modification of the third embodiment, 1
If one first mark and one second mark are made longer along the diagonal line as compared with the third embodiment, it can be used as a surveying target for long-distance measurement.

As a modification of each of the above-mentioned embodiments, 2
A cross line (not shown) may be provided at the intersection of the diagonal lines 16 and 17 of the book. This cross line is inclined by 45 ° with respect to the diagonal lines 16 and 17 which are orthogonal to each other.

According to this modification, it is possible to collimate the surveying target with the naked eye using the eyepiece of the telescope.

[0044]

As described above, according to the surveying target of the first aspect of the invention, the first mark and the second mark forming the target pattern have a width suitable for image processing, and a simple figure. Therefore, image processing is executed at high speed, target pattern extraction becomes easy,
The observation accuracy by image processing is improved.

According to the surveying target of the second aspect of the present invention, one of the two first marks and one of the two second marks are imaginary circles centering on an intersection of two imaginary lines. Since the other of the two first marks and the other of the two second marks are respectively located outside the virtual circle, it is possible to perform long-distance measurement and short-distance measurement. Therefore, during the short-distance measurement, the target pattern can be prevented from coming out of the image extraction area, and highly accurate image processing can be performed.

According to the surveying target of the third aspect of the invention, since both ends of the first mark and both ends of the second mark are each formed in an arc shape, this occurs when thinning the image processing. Noise can be reduced, and more accurate image processing can be performed.

[Brief description of the drawings]

FIG. 1 is a diagram showing a surveying target according to a first embodiment of the present invention.

FIG. 2 is an explanatory diagram for explaining a measuring operation using a surveying target and a measuring apparatus according to the first embodiment of the present invention.

FIG. 3 is a block diagram of the measuring apparatus of FIG.

FIG. 4 is a flowchart for explaining a procedure of automatic collimation when the surveying target of this embodiment is used.

FIG. 5 is a diagram showing a surveying target according to a second embodiment of the present invention.

FIG. 6 is a diagram showing a surveying target according to a third embodiment of the present invention.

FIG. 7 is a diagram showing a conventional surveying target.

[Explanation of symbols]

 12 Target for Surveying 14a to 14d First Mark 15a to 15d Second Mark 16,17 Diagonal Line

Claims (3)

[Claims] 1. A first mark arranged along one of two imaginary lines orthogonal to each other, and a second mark arranged along the other of the two imaginary lines, wherein: The target for surveying, wherein the mark and the second mark each have a width suitable for image processing. 2. The at least two first marks are arranged on the one virtual line, and the at least two second marks are arranged on the other virtual line, one of the two first marks and the one of the two first marks. One of the two second marks is located inside a virtual circle centered on the intersection of the two virtual lines, and the other of the two first marks and the two second marks The target for surveying according to claim 1, wherein the other is located outside the virtual circle. 3. The surveying target according to claim 1, wherein both ends of the first mark and both ends of the second mark are each formed in an arc shape.