KR101890256B1 - Space Coordinate Measurement System and Method of Space Coordinate Measurement Using the Same - Google Patents

Abstract

A spatial coordinate measurement system is provided. The spatial coordinate measuring system is configured to measure a first spatial coordinate of an object to be measured by capturing an object to be measured by using a first spatial coordinate of an object to be measured derived from an image sensing unit composed of two image sensing elements and an image sensing unit, And a tracking unit composed of three laser trackers for tracking the object and deriving a second spatial coordinate for a measurement object having a higher resolution than the first spatial coordinate. The laser trackers derive the second spatial coordinates of the measurement object using the multivariate method.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a space coordinate measurement system and a space coordinate measurement method using the same,

The present invention relates to a spatial coordinate measuring system and a spatial coordinate measuring method using the same, and more particularly, to a spatial coordinate measuring system having a high resolution for a wide area measuring object by using a laser tracker and a spatial coordinate measuring method using the same will be.

The key technologies that lead the high-tech industry including today's semiconductors, displays, and high-speed information communications require high precision in terms of hardware, and the precision required for them is large in the area of hundreds of millimeters (mm) Reaching a level of ultra-precision that implements the function in meters (nm).

The technical demand for ultra-high precision in such a large area requires a measurement technique that can be implemented in a wavelength range of light wavelengths of several tens to several tens of nanometers. Among these measurement techniques, an optical interferometer using a laser is capable of measuring at a resolution of several nanometers without damaging the object to be measured in a non-contact manner.

Since the conventional laser distance measurement technique is based on the principle of a relative distance interferometer that measures distances by accumulating measurement displacements, there is a problem in that errors occurring when measuring a displacement in a wide area are accumulated, There is a problem that the distance measurement information is lost because the distance change information can not be accumulated in the meantime.

In order to overcome this limitation, an absolute distance interferometer has been proposed. Unlike the conventional relative distance interferometer, there is an advantage that the distance can be measured at one time without accumulation of movement and measurement displacement of the object to be measured. Many researches are being conducted.

However, the femtosecond (fs) laser has recently been applied to improve the measurement accuracy and the multi-lateration method using a plurality of femtosecond laser-based absolute distance interferometers Studies are being conducted to measure coordinates. However, there is still insufficient technology to measure the distance and spatial coordinates of each of the plurality of measurement objects separately.

A problem to be solved by the present invention is to grasp an initial position in a space of a measurement object and to quickly perform a continuous measurement again when a position of the measurement object is missed during tracking, and the operation of the multidetropy algorithm is accurately and quickly performed And a spatial coordinate measurement system capable of effectively acquiring spatial coordinates of an object.

Another problem to be solved by the present invention is to grasp the initial position on the space of the measurement object and quickly perform the continuous measurement again when the position of the measurement object is missed and the operation of the multidetropy algorithm is performed accurately and quickly, And a spatial coordinate measuring method of the present invention.

The problems to be solved by the present invention are not limited to the above-mentioned problems, and other problems not mentioned can be clearly understood by those skilled in the art from the following description.

In order to achieve the above object, the present invention provides a spatial coordinate measurement system. The spatial coordinate measuring system is configured to measure a first spatial coordinate of an object to be measured by capturing an object to be measured by using a first spatial coordinate of an object to be measured derived from an image sensing unit composed of two image sensing elements and an image sensing unit, And a tracking unit composed of three laser trackers for tracking the object and deriving a second spatial coordinate for the measurement object having a higher resolution than the first spatial coordinate. The laser trackers can derive the second spatial coordinates of the measurement object using a multivariate method.

The image pickup element may be a cassette image sensor, and the image pickup section may be a stereo camera type.

The first spatial coordinates for the measurement object derived from the imaging unit may be two-dimensional or three-dimensional.

The first spatial coordinates may be for the initial position of the object to be measured or for the position of the object to be measured with the three laser tracers missing the object to be measured.

The laser tracker can generate a femtosecond laser beam.

The laser tracker can be connected to a laser interferometer to measure the absolute distance or relative distance while tracking the object being measured.

The tracing unit may further include one additional laser tracker.

According to another aspect of the present invention, there is provided a method of measuring spatial coordinates. This method can use the spatial coordinate measurement system described above. The method comprises the steps of: capturing an image of an object to be measured and deriving a first spatial coordinate for the object to be measured; and using the first spatial coordinates of the object to be measured derived by the image capturing unit, And deriving a second spatial coordinate for the measurement object having a higher resolution than the first spatial coordinate. The laser trackers can derive the second spatial coordinates of the measurement object using a multivariate method.

The first spatial coordinates for the measurement object derived from the imaging unit may be two-dimensional or three-dimensional.

The first spatial coordinates may be for the initial position of the object to be measured or for the position of the object to be measured with the three laser tracers missing the object to be measured.

Deriving the second spatial coordinates is to derive the spatial coordinates of the laser trackers using the non-linear least squares method, deriving the distance between the first spatial coordinate applying the initial value and the boundary condition and the object defining the spatial coordinate, and And deriving a second spatial coordinate of the measurement object using the first spatial coordinate applying the initial value and the boundary condition, the measured value of the distance to the measurement object, and the spatial coordinate derived by the laser trackers using the nonlinear least squares method .

The tracking unit, which further includes one additional laser tracker, can track the object to be measured and derive a second spatial coordinate for the object to be measured.

As described above, according to the solution of the problem of the present invention, when the imaging unit recognizes the initial position on the space to be measured and the tracking unit finds the position of the measurement target quickly, it is possible to continuously measure the measurement target . Accordingly, a spatial coordinate measurement system can be provided that can accurately and quickly perform the calculation of the multivariate analysis algorithm to efficiently acquire the spatial coordinates of the measurement object.

In addition, according to the solution of the problem of the present invention, it is possible to continuously measure an object to be measured by finding the initial position on the space of the object to be measured and quickly finding the position of the object to be measured. Accordingly, it is possible to provide a spatial coordinate measuring method capable of accurately and quickly performing an operation of a multivariate analysis algorithm to effectively acquire spatial coordinates of a measurement object.

1 is a block diagram illustrating a spatial coordinate measuring system according to an embodiment of the present invention.
2 is a block flow diagram illustrating a spatial coordinate measurement method using a spatial coordinate measurement system according to an embodiment of the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS The advantages and features of the present invention and the manner of achieving them will become apparent with reference to the embodiments described in detail below with reference to the accompanying drawings. However, the present invention is not limited to the embodiments described herein but may be embodied in different forms. Rather, the embodiments disclosed herein are provided so that the disclosure can be thorough and complete, and will fully convey the concept of the invention to those skilled in the art, and the invention is only defined by the scope of the claims.

Like reference numerals refer to like elements throughout the specification. Accordingly, although the same reference numerals or similar reference numerals are not mentioned or described in the drawings, they may be described with reference to other drawings. Further, even if the reference numerals are not shown, they can be described with reference to other drawings.

The terminology used herein is for the purpose of illustrating embodiments and is not intended to be limiting of the present invention. In the present specification, the singular form includes plural forms unless otherwise specified in the specification. It is to be understood that the terms 'comprises' and / or 'comprising' as used herein mean that an element, step, operation, and / or apparatus is referred to as being present in the presence of one or more other elements, Or additions. In addition, since they are in accordance with the preferred embodiment, the reference numerals presented in the order of description are not necessarily limited to the order. In addition, in this specification, when it is mentioned that a film is on another film or substrate, it means that it may be formed directly on another film or substrate, or a third film may be interposed therebetween.

It is to be understood that one element is referred to as being 'connected to' or 'coupled to' another component if it is directly connected or coupled to another component, As shown in Fig. On the other hand, when an element is referred to as being " directly coupled to " or " directly coupled to " another element, it means that it does not intervene in the other element. &Quot; and / or " include each and every combination of one or more of the mentioned items.

The terms 'below', 'beneath', 'lower', 'above', 'upper' and the like, which are spatially relative terms, May be used to easily describe a device or a relationship with components and other devices or components. Spatially relative terms should be understood in terms of the directions shown in the drawings, including the different directions of the device during use or operation. For example, when inverting a device shown in the figures, a device described as "below" or "beneath" of another device may be placed "above" another device. Thus, the exemplary term " below " may include both the downward and upward directions. The device can also be oriented in different directions, so that spatially relative terms can be interpreted according to orientation.

In addition, the embodiments described herein will be described with reference to cross-sectional views and / or plan views, which are ideal illustrations of the present invention. In the drawings, the thicknesses of the films and regions are exaggerated for an effective description of the technical content. Thus, the shape of the illustrations may be modified by manufacturing techniques and / or tolerances. Accordingly, the embodiments of the present invention are not limited to the specific forms shown, but also include changes in the shapes that are generated according to the manufacturing process. For example, the etched areas shown at right angles can be rounded and shaped with a certain curvature. Thus, the regions illustrated in the figures have schematic attributes, and the shapes of the regions illustrated in the figures are intended to illustrate specific forms of regions of the apparatus and are not intended to limit the scope of the invention.

FIG. 1 is a block diagram for explaining a spatial coordinate measuring system according to an embodiment of the present invention, and FIG. 2 is a block diagram for explaining a spatial coordinate measuring method using a spatial coordinate measuring system according to an embodiment of the present invention. Fig.

1 and 2, the spatial coordinate measuring system includes an imaging unit 120 for imaging a measurement target 100 and deriving a first spatial coordinate for the measurement target 100, A tracking unit 110 for tracking a measurement target 100 using first spatial coordinates of the measurement target 100 and deriving a second spatial coordinate for the measurement target 100 having a higher resolution than the first spatial coordinate .

The image pickup unit 120 may be composed of two image pickup elements. The image pickup device may be a CCD (charge-coupled device) image sensor, and the image pickup unit 120 may be a stereoscopic camera. Accordingly, the imaging unit 120 can derive the first spatial coordinates of the two-dimensional or three-dimensional form with respect to the measurement target 100. [

The tracking unit 110 may be composed of three laser trackers 112, 114, and 116 that track the object to be measured. The tracking unit 110 may further include one additional laser tracker 118. The tracking unit 110 further includes one additional laser tracker 118 so that the tracking unit 110 is faster in deriving the second spatial coordinates of the measurement object 100 and the approximate error can be further reduced have. The laser tracker 112, 114, 116, or 118 may generate a femtosecond laser beam. Further, the laser tracker 112, 114, 116, or 118 may be connected to the laser interferometer to measure the absolute distance or the relative distance while tracking the measurement target 100. The laser trackers 112, 114, 116, and 118 may derive the second spatial coordinates of the measurement object 100 using a multivariate method. That is, three or more laser trackers 112, 114, 116, and 118 may be used to measure the position coordinates of each laser tracker 112, 114, 116, or 118 and the respective laser tracker 112, 114, 116, The secondary spatial coordinates can be derived through the distance value to the object 100. [

In deriving the second spatial coordinates, we derive the spatial coordinates of the laser trackers using the nonlinear least squares method, which derives the distance between the first spatial coordinate applying the initial value and the boundary condition and the object defined the spatial coordinate. The first spatial coordinate applying the initial value and the boundary condition, the distance measurement value of the measurement object 100, and the spatial coordinates derived by the laser trackers 112, 114, 116, and 118 are compared with the nonlinear least squares method And the second spatial coordinate of the measurement object 100 is derived using the spatial coordinate measurement step.

The multivariate algorithm specifies a local coordinate system based on the positional coordinates of three or more laser trackers 112, 114, 116, and 118 derived in advance or self-calibrated. The distance from each laser tracker 112, 114, 116 or 118 to the object of measurement 100 is measured. A nonlinear least squares method is applied to calculate the distance values measured at each laser tracker 112, 114, 116 or 118 and the position coordinates of the respective laser tracker 112, 114, 116 or 118 and the unknown The second spatial coordinate of the measurement object 100 can be derived such that the error of the spatial coordinate is minimized. When the nonlinear least squares method is applied, the approximation speed of the muscle and the approximate error occurrence may be influenced by the initial value. That is, by setting the threshold value corresponding to the solution, the approximation speed can be increased, and the approximate error can be reduced.

When the spatial coordinate measurement of the measurement object 100 by the multivariate measurement method is performed through three or more laser trackers 112, 114, 116 and 118 through a measurement algorithm and applied to the multidetropy algorithm, The second spatial coordinates of the first image 100 may be derived. In this case, the nonlinear least squares method is applied to derive the second spatial coordinates of the measurement object 100 at the distance value measured by each of the three or more sides, which is performed by using the laser trackers 112, 114, 114, 116, and 118, which are values that are previously known values due to self-calibration or measurement, and a plurality of measured distance values that are actually measured distance values between the measurement targets 100, 116, and 118 The solution corresponding to the second spatial coordinate of the measurement object 100 can be approximated so that the error of the distance between the position coordinate and the second spatial coordinate of the unknown object 100 is minimized. In this case, the nonlinear least squares method affects the approximation speed according to the initial value, and the approximated solution may give an incorrect result. Therefore, by setting the approximate first spatial coordinate for the measurement object 100 derived by the imaging unit 120 as the boundary condition in the measurement algorithm, it is possible to determine the second spatial coordinate of the measurement object 100 by the nonlinear least squares method And errors of the second spatial coordinates of the measurement object 100 can be reduced.

Also, in the multivariate method, it is possible to derive the second spatial coordinates for the measurement object 100 in the three-dimensional form using the three laser trackers 112, 114, and 116, but a sign error for the z- have. In addition, one additional laser tracker 118 may be needed to obtain the positional coordinates of each of the laser trackers 112, 114, and 116 through self-calibration. However, since imaging section 120 can replace the role of one additional laser tracker 118, a dense spatial coordinate measuring system consisting of only three laser trackers 112, 114 and 118 can be constructed have.

In addition, in order to derive the second spatial coordinates of the three-dimensional shape of the measurement object 100 in the multivariate measurement method, it is first necessary to know the positional coordinates of the laser trackers 112, 114 and 116. This is practically difficult to apply, although it may be measured directly using other measurement devices, and self-calibrating is applied to derive the positional coordinates of each of the laser trackers 112, 114 and 116, which are also based on nonlinear least squares Can be obtained. That is, approximate positional coordinates of each of the three or more laser trackers 112, 114, 116, and 118 are obtained through the imaging unit 120, and by applying them to the boundary condition of the nonlinear least squares method, The approximation speed for the solution corresponding to the second spatial coordinate of the measurement object 100 can be increased and the approximate error can be reduced so that the solution corresponding to the second spatial coordinate of the measurement object 100 can be closer to the ideal value.

When deriving the second spatial coordinates for the measurement object 100 by the multivariate measurement method, the image pickup section 120 grasps the initial position of the measurement object 100 or acquires the position of the laser trackers 112, 114, 116, and 118 Can miss the measurement object 100, it can play a role for finding the measurement object 100 quickly. Since the object 100 is tracked by the laser trackers 112, 114, 116, and 118 when deriving the second spatial coordinates for the object 100 to be measured by the multidetector method on the moving object 100, A second spatial coordinate for the measurement object 100 can be derived in real time. The laser trackers 112, 114, 116 and 118 then irradiate the laser beam to an initial position for a given measurement object 100, which is derived through the imaging section 120, And 118, respectively, of the measurement object 100. [0033] FIG.

Further, when the laser beam is disconnected due to an obstacle or the like while measuring the distance between each of the laser tracers 112, 114, 116, and 118 and the measurement target 100, when the measurement target 100 is missed, Each of the sensors 112, 114, 116, and 118 may receive information about the position of the measurement object 120 with the image pickup unit 120, and perform tracking and real-time distance measurement on the measurement object 100 again.

When deriving the second spatial coordinates for the measurement object 100 by the multivariate measurement method, the respective second spatial coordinates for the plurality of measurement objects 100 can be derived. When the laser tracers 112, 114, 116, and 118 are applied to track a plurality of measurement objects 100 respectively and to derive a second spatial coordinate, a plurality of measurement targets The first spatial coordinates of the initial three-dimensional shape of each of the three-dimensional shapes 100 may be provided at the same time. This makes it possible to irradiate a plurality of measurement objects 100 with a laser beam and simultaneously provides a boundary condition on a multivariate measurement algorithm for a plurality of measurement objects 100 to quickly and accurately measure a plurality of measurement objects 100 ≪ / RTI > can be derived.

The spatial coordinate measuring system and the spatial coordinate measuring method using the spatial coordinate measuring system according to an embodiment of the present invention include an imaging unit that grasps an initial position on a space of a measurement subject and can quickly find the position of the measurement target when the tracking unit misses, Continuous measurement of the measurement object may be possible. Accordingly, it is possible to provide a spatial coordinate measuring system and a spatial coordinate measuring method using the same, which can accurately and rapidly perform the calculation of the multidetropy algorithm to acquire the spatial coordinate of the measuring object effectively.

While the present invention has been described in connection with what is presently considered to be practical exemplary embodiments, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, It will be understood. It is therefore to be understood that the above-described embodiments are illustrative and non-restrictive in every respect.

100: Measurement object
110:
112, 114, 116, 118: first, second, third and fourth laser trackers
120:

Claims (12)

An imaging apparatus comprising: an imaging unit configured to acquire a first spatial coordinate for an object to be measured by photographing a measurement object, the imaging unit comprising two imaging elements; And
And a second spatial coordinate detector for tracking the measurement object using the first spatial coordinate with respect to the measurement object derived from the imaging unit to derive a second spatial coordinate for the measurement object having a higher resolution than the first spatial coordinate, Wherein the laser trackers derive the second spatial coordinates of the measurement object using a multivariate measurement method,
Deriving the second spatial coordinates comprises:
Deriving the spatial coordinates of the laser trackers using a nonlinear least squares method that derives the distance between the first spatial coordinate and the spatial coordinate defined by applying the initial value and the boundary condition; And
A first spatial coordinate applying the initial value and the boundary condition, a value obtained by measuring a distance of the object to be measured, and a spatial coordinate derived by the laser tracers, using the nonlinear least squares method, And deriving spatial coordinates. The method according to claim 1,
Wherein the image pickup element is a scyed image sensor, and the image pickup unit is a stereo camera system. The method according to claim 1,
Wherein the first spatial coordinate for the measurement object derived from the imaging unit is a two-dimensional or three-dimensional shape. The method according to claim 1,
Wherein the first spatial coordinates are for an initial position of the measurement object or for the position of the measurement object in a state where the three laser trackers miss the measurement object. The method according to claim 1,
Wherein the laser tracker generates a femtosecond laser beam. The method according to claim 1,
Wherein the laser tracker is connected to a laser interferometer to measure an absolute distance or a state distance while tracking the object to be measured. The method according to claim 1,
Wherein the tracking unit further comprises one additional laser tracker. A method for measuring spatial coordinates using the spatial coordinate measuring system according to claim 1,
The imaging unit photographing the measurement object to derive a first spatial coordinate for the measurement object; And
Wherein the tracking unit tracks the measurement object with the three laser tracers in the tracking unit using the first spatial coordinates of the measurement object derived from the imaging unit, Wherein the laser trackers derive the second spatial coordinates of the measurement object using a multivariate measurement method,
Deriving the second spatial coordinates comprises:
Deriving the spatial coordinates of the laser trackers using a nonlinear least squares method that derives the distance between the first spatial coordinate and the spatial coordinate defined by applying the initial value and the boundary condition; And
A first spatial coordinate applying the initial value and the boundary condition, a value obtained by measuring a distance of the object to be measured, and a spatial coordinate derived by the laser tracers, using the nonlinear least squares method, And deriving spatial coordinates. 9. The method of claim 8,
Wherein the first spatial coordinate for the measurement object derived from the imaging unit is a two-dimensional or three-dimensional shape. 9. The method of claim 8,
Wherein the first spatial coordinates are for the initial position of the measurement object or for the position of the measurement object in a state where the three laser trackers miss the measurement object. delete 9. The method of claim 8,
Wherein the tracking unit further includes an additional laser tracker for tracking the measurement object to derive the second spatial coordinate for the measurement object.

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