KR20140075545A - Method for measuring spin character of rotating body and apparatus thereof - Google Patents

Abstract

Disclosed are a method for measuring the spin character of a rotating body and an apparatus thereof. A method for measuring the spin character of a rotating body according to one embodiment of the present invention includes a step of generating a correction matrix based on correction information on the internal variable of a measuring apparatus and correction information on an external variable, a step of acquiring spin images with regard to the rotating body according to different magnification, and a step of generating the reference positions of the rotating body based on the correction matrix and the position information of the rotating images. According to the present invention, the spin character of the rotating body can be accurately measured.

Description

TECHNICAL FIELD [0001] The present invention relates to a rotating body,

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for measuring rotation characteristics of a rotating body, and more particularly, to a method and an apparatus for measuring rotation characteristics of a rotating body for measuring rotation characteristics such as linear velocity and angular velocity of the rotating body.

Generally, the technique of measuring the rotation characteristics (e.g., linear velocity, angular velocity, etc.) of the rotating body is widely used in the field of virtual sports game using motion simulations of rotating bodies such as virtual golf, baseball, soccer, and tennis game.

A technique for measuring a rotation characteristic of a conventional rotating body using a radar, a technique for measuring a rotation characteristic using a camera, and the like. A technique for measuring the rotation characteristics using a radar is to use a Doppler radar to transmit a high frequency signal to the rotating body and analyze the characteristics (for example, size, modulation characteristics, etc.) of the high frequency signal reflected from the rotating body, Measure the rotation characteristics. Such a radar system can accurately measure the linear velocity and rotation rate of the rotating body, but it can not directly measure the rotation axis of the rotating body, and there is a problem that a cost for the development of a radar-based rotation characteristic measurement system is consumed.

On the other hand, the technique of measuring the rotation characteristics using a camera measures the rotation characteristics of the rotation body by analyzing the image of the rotation body acquired through the camera. Such a camera system can accurately measure the linear velocity and angular velocity of a rotating body when an expensive high-speed camera is used. However, there is a problem that a high-speed camera-based rotation characteristic measuring system is costly to develop.

On the other hand, if a multiple exposure camera is used, the rotation characteristic measurement system can be developed at a low cost. However, the rotation characteristic measurement system based on the multiple exposure camera can not accurately measure the linear velocity and angular velocity of the rotation body.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a method of measuring the rotation characteristics of a rotating body for accurately measuring a rotation characteristic of a rotating body based on a binocular multiple exposure camera.

It is another object of the present invention to provide an apparatus for measuring the rotation characteristics of a rotating body for accurately measuring a rotation characteristic of a rotating body based on a binocular multiple exposure camera.

According to another aspect of the present invention, there is provided a method of measuring rotation characteristics of a rotating body, the method including generating a correction matrix based on correction information on an internal variable of the measurement apparatus and correction information on an external variable, Acquiring a plurality of rotation images of the rotating body according to different magnifications, and generating reference positions of the rotating body based on the correction matrix and the position information of the plurality of rotation images.

The generating of the correction matrix may include obtaining a plurality of correction images for the correction plate according to different magnifications, generating correction information for the internal variables based on the plurality of correction images, Generating correction information for the external variable based on the position information of the apparatus, and generating the correction matrix based on the correction information for the internal variable and the correction information for the external variable.

The generating of the reference positions of the rotating body includes generating two-dimensional position information of the rotating body on the basis of the plurality of rotating images, based on the correction matrix and the two-dimensional position information of the rotating body Dimensional position information of the rotating body and three-dimensional position information in which a difference between the three-dimensional position information of the rotating body and the two-dimensional position information satisfies a predetermined criterion is determined as a reference position of the rotating body .

The method may further include calculating a linear velocity of the rotating body based on a difference between reference positions of the rotating body.

The method may further include calculating an angular velocity of the rotary body based on a change in rotation between reference positions of the rotary body.

The step of calculating the angular velocity of the rotating body may include selecting two-dimensional position information corresponding to reference positions of a rotation image having a relatively high magnification among the plurality of rotation images, Generating two-dimensional candidate position information in which an error with respect to a center point of the rotating body is corrected, and generating two-dimensional candidate position information in which an error with respect to a center point of the rotating body is corrected, Generating a matrix and calculating an angular velocity of the rotary body based on the rotation matrix.

According to another aspect of the present invention, there is provided an apparatus for measuring rotation characteristics of a rotating body, including a first obtaining unit obtaining a first rotated image of a rotating body and a first corrected image of a compensating plate, A second acquiring unit acquiring a second rotated image of the rotating body and a second corrected image of the compensating plate at a magnification different from that of the first acquiring unit and a second acquiring unit acquiring the first corrected image, Generates a correction matrix based on the position information on the first obtaining unit and the position information on the second obtaining unit, and generates a reference position of the rotating body based on the correction matrix, the first rotating image, and the second rotating image And a processing unit.

Here, the processing unit may generate correction information for an internal variable based on the first corrected image and the second corrected image, and may include position information on the first obtaining unit and position information on the second obtaining unit And generates the correction matrix based on the correction information for the internal variable and the correction information for the external variable.

Here, the processing unit generates two-dimensional position information of the rotating body on the basis of the first rotating image and the second rotating image, and based on the correction matrix and the two-dimensional position information of the rotating body, Dimensional position information of the rotating body and determine three-dimensional position information, which is a difference between the three-dimensional position information of the rotating body and the two-dimensional position information, satisfies a predetermined reference as the reference position of the rotating body.

Here, the processing unit may calculate the linear velocity of the rotating body based on a difference between reference positions of the rotating body.

Here, the processing unit may calculate the angular velocity of the rotary body based on the rotation change between the reference positions of the rotary body.

Here, the processing unit may select two-dimensional position information corresponding to reference positions of a rotation image having a relatively high magnification among the first rotation image and the second rotation image, and based on the two-dimensional position information, Dimensional candidate position information with the error of the entire center point is corrected and a rotation matrix is generated based on the rotation variation whose error according to the image matching among the rotation changes according to the two- And the angular velocity of the rotating body can be calculated based on the rotation matrix.

According to the present invention, it is possible to accurately measure the rotation characteristics (e.g., linear velocity, angular velocity, and the like) of the rotating body by correcting the error of the rotating body image using the correction information. Further, the linear velocity and angular velocity of the rotating body can be measured simultaneously.

1 is a flowchart illustrating a method for measuring rotation characteristics of a rotating body according to an embodiment of the present invention.
2 is a flowchart showing a step of generating a correction matrix in a method of measuring rotation characteristics of a rotating body according to an embodiment of the present invention.
FIG. 3 is a flowchart illustrating a step of generating a reference position in a method of measuring rotation characteristics of a rotating body according to an embodiment of the present invention.
4 is a flowchart showing a step of calculating an angular velocity in a method for measuring rotation characteristics of a rotating body according to an embodiment of the present invention.
5 is a block diagram illustrating an apparatus for measuring rotation characteristics of a rotating body according to an embodiment of the present invention.
FIG. 6 is a conceptual diagram showing an installation state of an apparatus for measuring rotation characteristics of a rotating body according to an embodiment of the present invention.
7 is a conceptual diagram showing a process of measuring the linear velocity of the rotating body.
8 is a conceptual diagram showing a process of measuring the angular velocity of the rotating body.
9 is a conceptual diagram showing a process of calculating a rotation change in a process of measuring the angular velocity of the rotating body.

While the invention is susceptible to various modifications and alternative forms, specific embodiments thereof are shown by way of example in the drawings and will herein be described in detail.

It should be understood, however, that the invention is not intended to be limited to the particular embodiments, but includes all modifications, equivalents, and alternatives falling within the spirit and scope of the invention.

The terms first, second, etc. may be used to describe various components, but the components should not be limited by the terms. The terms are used only for the purpose of distinguishing one component from another. For example, without departing from the scope of the present invention, the first component may be referred to as a second component, and similarly, the second component may also be referred to as a first component. And / or < / RTI > includes any combination of a plurality of related listed items or any of a plurality of related listed items.

It is to be understood that when an element is referred to as being "connected" or "connected" to another element, it may be directly connected or connected to the other element, . On the other hand, when an element is referred to as being "directly connected" or "directly connected" to another element, it should be understood that there are no other elements in between.

The terminology used in this application is used only to describe a specific embodiment and is not intended to limit the invention. The singular expressions include plural expressions unless the context clearly dictates otherwise. In the present application, the terms "comprises" or "having" and the like are used to specify that there is a feature, a number, a step, an operation, an element, a component or a combination thereof described in the specification, But do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, or combinations thereof.

Unless defined otherwise, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Terms such as those defined in commonly used dictionaries should be interpreted as having a meaning consistent with the meaning in the context of the relevant art and are to be interpreted in an ideal or overly formal sense unless explicitly defined in the present application Do not.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In order to facilitate the understanding of the present invention, the same reference numerals are used for the same constituent elements in the drawings and redundant explanations for the same constituent elements are omitted.

1 is a flowchart illustrating a method for measuring rotation characteristics of a rotating body according to an embodiment of the present invention.

Referring to FIG. 1, a method of measuring rotation characteristics of a rotating body according to an embodiment of the present invention includes generating correction matrixes based on correction information on internal variables and correction information on external variables of a rotation property measurement apparatus (S300) of generating a plurality of rotation images for the rotating body in accordance with different magnifications (S200), generating reference positions of the rotating body based on the correction matrix and position information of the plurality of rotating images (S300) And measuring the rotation characteristics (e.g., linear velocity, angular velocity, etc.) of the rotating body based on the reference positions (S400).

5 may be performed by the rotation property measurement apparatus 10 and the rotation property measurement apparatus 10 may include a first acquisition unit 11, a second acquisition unit 12, (13). The first acquiring unit 11 and the second acquiring unit 12 may use a multiple exposure camera and the first acquiring unit 11 and the second acquiring unit 12 may use a lens having a different magnification, Can be obtained. For example, the first acquiring unit 11 can acquire an image using a lens having a larger magnification than the second acquiring unit 12.

 FIG. 6 is a conceptual diagram showing an installation state of an apparatus for measuring rotation characteristics of a rotating body according to an embodiment of the present invention.

도로 설정할 수 있고, 제2 획득부(12)의 틸트 각도는 0도, 롤 각도는 0도, 팬 각도는

도로 설정할 수 있다. 아울러, 회전체의 각속도를 측정하기 위해 색상 대비(contrast)가 높은 패턴을 가지는 회전체를 사용할 수 있다.6, the first acquiring unit 11 and the second acquiring unit 12 can be installed at a position of h meters in height from the batting seat 30 (i.e., the position where the rotating body strikes) The interval between the first obtaining unit 11 and the second obtaining unit 12 may be set to be g meter. At this time, the tilt angle of the first obtaining unit 11 is set to 0 degrees and the roll angle is set to 0 degrees so that the directions of the first obtaining unit 11 and the second obtaining unit 12 face the center of the plate. 0 degrees, the pan angle is

The tilt angle of the second acquiring unit 12 is 0 degree, the roll angle is 0 degree, and the fan angle is

You can set the road. Further, in order to measure the angular velocity of the rotating body, it is possible to use a rotating body having a high contrast in color.

2 is a flowchart showing a step of generating a correction matrix in a method of measuring rotation characteristics of a rotating body according to an embodiment of the present invention.

Referring to FIGS. 2 and 6, the step of generating the correction matrix may include obtaining a plurality of correction images for the correction plate 20 according to different magnifications (S110) (S130) of generating correction information for an external variable on the basis of the position information of the measurement apparatus (S130), and generating correction information based on the correction information for the internal variable and the correction information for the external variable And generating a matrix (S140).

The rotation characteristic measuring apparatus can acquire a plurality of correction images for the correction plate 20 according to different magnifications (S110). Here, the compensation plate 20 may be located at the center of the batter seat 30, and the compensation plate 20 may have a length of C _x meters and a length C _y meters. The first acquiring unit 11 of the rotational property measuring apparatus can acquire the first corrected image 21 for the correction plate 20 through a single exposure and the first corrected image 21 has the horizontal resolution n _x pixels, And may have a vertical resolution n _y pixels. The first corrected image 21 may have a width r _x pixels and a length r _y pixels and may have a horizontal center line of the first corrected image 21 obtained through the first obtaining unit 11 (Or the horizontal center line) of the correction plate in the first corrected image 21 to the horizontal center line may have the y _r pixel in the lower direction.

For example, when the resolution of the first corrected image 21 is 640 pixels wide by 580 pixels high, the horizontal center line (or the horizontal center line) of the first corrected image 21 is vertically 290 pixels, Y _r has 60 pixels (i.e., y _r = 350 - 290) when the horizontal centerline (or horizontal centerline) of the correction plate in the corrected image 21 is located on 350 pixels vertically.

On the other hand, the second acquiring unit 12 of the rotational characteristic apparatus can acquire the second corrected image 22 for the correction plate 20 through a single exposure, and the second corrected image 22 can acquire the corrected resolution n _x , And a vertical resolution n _y pixels. Also, the second corrected image 22 is the width l _x pixels, and the height l _y may have a pixel, and a second transverse center line of the second calibration image 22 is obtained by means of the acquisition unit 12 (or, second correction image from the horizontal center line) 22 in the horizontal center line of the compensation plate (or the length of the horizontal center line) may have a _l y pixels in the upper direction.

For example, when the resolution of the second corrected image 22 is 640 pixels wide by 580 pixels high, the horizontal center line (or the horizontal center line) of the second corrected image 22 is vertically located on 290 pixels, If the horizontal centerline (or horizontal centerline) of the correction plate in the corrected image 22 is located on 350 pixels vertically, y _l is 60 pixels (i.e., y _l = 350-290).

The rotation characteristic measuring apparatus can generate correction information for an internal variable based on a plurality of corrected images (i.e., the first corrected image 21 and the second corrected image 22) (S120). That is, based on the information about the first corrected image 21 and the second corrected image 22 acquired in step S110, the rotation characteristic measuring apparatus calculates correction information ( _Kr , K _l ) < / RTI >

In Equation (1), K _r denotes correction information for the internal variable of the first acquisition unit 11, and K ₁ denotes correction information for the internal variable of the second acquisition unit 12. That is, Equation (1) can be used to generate correction information for internal variables of the first acquisition unit 11 and the second acquisition unit 12 without using a separate camera calibration technique.

The rotation characteristic measuring apparatus may generate correction information for the external variable based on the position information of the first acquiring unit 11 and the second acquiring unit 12 (S130). That is, the rotation characteristic measurement apparatus calculates the rotation characteristic of the external variable based on the position information (i.e., tilt angle, roll angle, fan angle) of the first acquisition unit 11 and the second acquisition unit 12, It may generate the correction information _{(r r,} r _l).

In Equation (2), R _r denotes correction information for an external variable of the first acquisition unit 11, and R ₁ denotes correction information for an external variable of the second acquisition unit 12.

The rotation characteristic measuring apparatus may generate a translation vector according to the following equation (3) based on the interval information between the first acquiring unit 11 and the second acquiring unit 12.

In Equation (3), t _r means a motion vector for the first acquiring unit 11, and t _l means a motion vector for the second acquiring unit 12.

The rotation characteristic measuring apparatus can generate a correction matrix based on the correction information on the internal variable, the correction information on the external variable, and the motion vector (S140). That is, the rotation characteristic measuring apparatus can generate the correction matrix P _r , P _l through the following equation (4).

In Equation (4), P _r means a correction matrix for the first acquisition unit 11, and P _l means a correction matrix for the second acquisition unit 12.

In the description of the step of generating the correction matrix, the correction information for the internal variable is generated and then the correction information for the external variable is generated. However, the process for generating the correction matrix is not limited to this, After generating the information, the correction information for the internal variable can be generated.

The rotation characteristic measuring apparatus can acquire a plurality of rotation images for the rotating body 40 (refer to FIG. 7) according to different magnifications (S200). That is, the rotation characteristic measuring apparatus includes a first rotation image 31 (see FIG. 7) having different magnifications through the first acquiring unit 11 and a second acquiring unit 12 having lenses having different magnifications, The rotation image 32 (see Fig. 7) can be obtained.

At this time, the rotation characteristic measuring apparatus can continuously obtain the first rotation image 31 and the second rotation image 32 for the rotating body 40 by performing N times of exposure at least twice, The minimum value (dt _min ) can be calculated by the following equation (5).

In Equation (5), D denotes the actual diameter of the rotating body 40, and v _max denotes the maximum speed of the rotating body 40. That is, the rotation characteristic measuring apparatus can acquire the first rotation image 31 and the second rotation image 32, which are multiple exposure images, using the minimum value of the exposure interval calculated through Equation (5).

The rotation characteristic measuring apparatus can generate a reference position of the rotation body based on the position information of the correction matrix and the plurality of rotation images (S300).

FIG. 3 is a flowchart illustrating a step of generating a reference position in a method of measuring rotation characteristics of a rotating body according to an embodiment of the present invention.

3 and 7, the step of generating the reference position includes generating (S310) two-dimensional position information of the rotating body on the basis of the plurality of rotating images, (S320) of generating three-dimensional position information of the rotating body and determining the three-dimensional position information whose difference from the two-dimensional position information among the three-dimensional position information of the rotating body satisfies a predetermined criterion as the reference position of the rotating body (Step S330).

The rotation characteristic measuring apparatus can generate two-dimensional position information (e.g., center point, diameter, etc.) of the rotating body based on the first rotation image 31 and the second rotation image 32 (S310 ). Here, the apparatus for measuring rotation characteristics includes image processing and image processing such as background subtraction and connected component labeling, area filtering, circle fitting, vision method, it is possible to calculate the center point, diameter, etc. of the rotating body based on a plurality of rotated images.

In other words, the rotation characteristic measuring device measures N rotator center points {X _r1 , ..., N) in the order of time from the first rotation image 31. , X _rN } and the diameter D _r, and obtains N rotational center points {X _{l 1} , ..., X n} from the second rotated image 32 in order of time. , X _lN } and the diameter D _l . In this case, the rotational property measurement apparatus rotational center point in the first rotary image (31) X _r = (x _r, y _r) and the second rotating body in the rotating image 32 is the center point X _l = (x _l, y _l) The center point and the diameter of the rotating body can be calculated so as to satisfy Equation (6) below.

를 생성할 수 있다.The rotation characteristic measuring apparatus can generate three-dimensional position information of the rotating body on the basis of the correction matrix and the two-dimensional position information of the rotating body (S320). That is, the rotation characteristic measuring apparatus includes a correction matrix P _r for the first acquiring unit 11, a correction matrix P _l for the second acquiring unit 12, n (n) acquired from the first rotation image 31, second time the center point of the entire X _rn = (x _rn, y _rn), the second rotary image 32, the n-th time the center point of the entire X _ln = equation below 7 based on the (x _ln, y _ln) obtained from The three-dimensional position information of the rotating body

Lt; / RTI >

는

의 동차 좌표(homogeneous coordinate) 벡터로서

이다. 즉, 회전 특성 장치는 3차원 위치 정보를 선형 기법(linear method)을 통해 산출할 수 있다.In Equation (7)

The

As a homogeneous coordinate vector

to be. That is, the rotation characteristic device can calculate the three-dimensional position information through a linear method.

The rotation characteristic measuring apparatus may determine the reference position of the rotating body as the three-dimensional position information in which the difference between the two-dimensional position information of the three-dimensional position information of the rotating body satisfies a predetermined reference (S330). In other words, the rotation characteristic measuring apparatus includes a reconstruction error corresponding to the difference between the position where the three-dimensional position information is projected on the first rotation image 31 and the two-dimensional position information (i.e., the center point) Dimensional position information (i.e., the center point) of the rotating body and the projection position of the second rotating image 32 to the second rotating image 32, Dimensional position information (i.e., reference position) X _n , Y _n , Z of the rotating body that minimizes a normalized reconstruction error (NRCE) normalized through the entire diameter (D _r , D ₁ ) _n can be calculated through a nonlinear method.

In Equation (8), the normal restoration error (NRCE) can be calculated by the following Equation (9) based on the rotating radius D _r of the first rotating image 31 and the rotating radius D _l of the second rotating image 32 have.

는 회전체의 3차원 위치 정보 X_n을 제1 회전 영상(31)에 투영한 위치이고,

는 회전체의 3차원 위치 정보 X_n을 제2 회전 영상(32)에 투영한 위치이다.

와

는 아래 수학식 10을 통해 산출할 수 있다.In Equation (9)

Dimensional position information X _n of the rotating body onto the first rotation image 31,

Dimensional position information X _n of the rotating body onto the second rotated image 32. [

Wow

Can be calculated by the following equation (10).

In this manner, the rotation-property measurement apparatus calculates the three-dimensional position information {X ₁ , ..., Xn based on the equations (8) to , X _N }, and generates three-dimensional position information {X ₁ , ..., X _N }. , X _N} from the normal error recovery (NRCE) the two smallest point X _s (see Fig. 8a) (see Fig. 8a) and X _e is possible to determine the reference position of the rotor as a whole.

The rotation characteristic measuring apparatus can calculate the linear velocity of the rotating body based on the difference between the reference positions (S400).

7 is a conceptual diagram showing a process of measuring the linear velocity of the rotating body.

Referring to FIG. 7, reference numeral 31 denotes a first rotation image acquired through the first acquisition unit 11, reference numeral 32 denotes a second rotation image acquired through the second acquisition unit 12, . The rotation characteristic measuring apparatus includes a rotation unit 40 based on the first rotation image 31 acquired through the first acquisition unit 11 and the second rotation image 32 acquired through the second acquisition unit 12, Can be measured.

로부터 회전체의 선속도

를 산출할 수 있다.That is, the position change between the rotational property measurement apparatus based on the position of the rotating body through the following equation (11) X _s (see Fig. 8a) and X _e (see Figure 8a)

The linear velocity of the rotating body

Can be calculated.

The rotation characteristic measuring apparatus can calculate the angular velocity of the rotating body based on the rotation change between the reference positions (S400).

4 is a flowchart showing a step of calculating an angular velocity in a method for measuring rotation characteristics of a rotating body according to an embodiment of the present invention.

Referring to FIG. 4, the step of calculating the angular velocity of the rotating body may include selecting (S410) two-dimensional position information corresponding to reference positions of a rotation image having a relatively high magnification among a plurality of rotation images, Dimensional candidate position information in which the error with respect to the center point of the rotating body is corrected based on the position information of the two-dimensional candidate position information (S420) A step S430 of generating a rotation matrix based on the rotation matrix and a step S440 of calculating an angular velocity of the rotation based on the rotation matrix.

8 is a conceptual diagram showing a process of measuring the angular velocity of the rotating body.

8, 8a is the reference position will showing a first rotating image 31 having a relatively high magnification of the plurality of rotating images, 8b and 8c is a first rotating image 31 X _re ( Or X _rs ), the rotation matrix according to the rotation change is calculated.

The rotation property measuring apparatus may select two-dimensional position information corresponding to reference positions of the rotation image having a relatively high magnification among the plurality of rotation images (i.e., the first rotation image and the second rotation image) (S410).

를 생성할 수 있다.The rotation characteristic measuring apparatus can generate the two-dimensional candidate position information in which the error with respect to the center point of the rotating body is corrected based on the two-dimensional position information of the rotating body (S420). That is, since the result of the three-dimensional image matching based on the rotation matrix can be different according to the rotation axis and the center point extraction error, the center point extraction error (d _rx , d _ry ) is corrected to the center point (X _rs , X _re ) Two-dimensional candidate position information of one round

Lt; / RTI >

9 is a conceptual diagram showing a process of calculating a rotation change in a process of measuring the angular velocity of the rotating body.

Referring to FIG. 9, reference numeral 91 denotes two-dimensional position information before correction of the extraction error, and reference numeral 93 denotes two-dimensional position information in which extraction errors are corrected. Reference numeral 92 denotes three-dimensional position information according to reference numeral 91, and reference numeral 94 denotes three-dimensional position information according to reference numeral 93.

The rotation characteristic measuring apparatus may generate a rotation matrix based on the rotation variation in which the error according to the image matching among the rotation changes according to the two-dimensional candidate position information satisfies a predetermined criterion (S430).

로 하여 아래 수학식 12와 같이 나타낼 수 있다.First, the rotation property measuring apparatus applies a 3-dimensional rotation image-based three-dimensional image registration technique to a rotating body surface image within a radius d _r according to two-dimensional position information (X _rs , X _re ) It is possible to calculate the rotation matrix dR according to the three-dimensional rotation variation of the rotation matrix dR. The rotation matrix dR of the rotating body

And can be expressed as Equation (12) below.

을 산출할 수 있다.The rotation characteristic measuring apparatus calculates the normalized registration error (NRGE) normalized through the size A of the surface image matching region as the additional parameter d _rx and d _ry as shown in Equation (13) below

Can be calculated.

In Equation (13), the normalized matching error NRGE can be calculated by Equation (14) below.

U (x, y, d _r ) in Equation (14) can be calculated by Equation (15) below. If (x, y) is within the radius d _r at the origin, _r ) is 1, otherwise U (x, y, d _r ) is zero.

이 양수(positive)이면 V(x,y,dR)는 1이고, 그렇지 않으면 V(x,y,dR)는 0이다.In Equation (14), V (x, y, dR) is a function representing visibility and can be calculated by the following expression (16) After rotating the dimension point (x, y, z) by dR, the height of the rotating body

(X, y, dR) is 1 if it is positive, otherwise V (x, y, dR) is zero.

은 아래 수학식 17을 통해 산출할 수 있다.In equation (16)

Can be calculated by the following equation (17).

In Equation (17), z can be calculated by Equation (18) below.

는 dR만큼 회전된 회전체의 픽셀 값 차이를 나타내는 함수로서 아래 수학식 19를 통해 산출할 수 있다.In Equation (14)

Is a function representing the difference in pixel value of the rotating body rotated by dR, and can be calculated through Equation (19) below.

In Equation 19, x _dR can be calculated by Equation (20) and y _dR can be calculated by Equation (21) below.

In Equation (14), A is a function indicating the size of an image area satisfying equations (15) and (16) simultaneously, and can be calculated through Equation (22) below.

을 산출할 수 있고, 이를 기반으로 회전 행렬 dR을 산출할 수 있다.As described above, through the equations (12) to (22), the normal matching error NRGE is minimized

And the rotation matrix dR can be calculated based on the rotation matrix dR.

를 산출할 수 있다(S440). The rotation characteristic measuring device measures the angular velocity of the rotating body based on the rotation matrix

(S440).

을 아래 수학식 23을 통해 산출할 수 있고, 크기(norm)

를 아래 수학식 24를 통해 산출할 수 있다.In order to calculate the angular velocity of the rotating body,

Can be calculated by the following equation (23)

Can be calculated through Equation (24) below.

In Equation 24, u may be selected to satisfy the following Equation 25 as an orthogonal vector of n.

과

를 아래 수학식 26에 적용하여 회전체의 각속도를 산출할 수 있다.
The rotation-property measuring device calculates the rotation-

and

Can be applied to Equation (26) below to calculate the angular velocity of the rotating body.

5 is a block diagram illustrating an apparatus for measuring rotation characteristics of a rotating body according to an embodiment of the present invention.

5, an apparatus 10 for measuring rotational characteristics of a rotating body according to an embodiment of the present invention may include a first obtaining unit 11, a second obtaining unit 12, and a processing unit 13 . The first obtaining unit 11 can obtain the first rotated image 31 (see Fig. 7) and the first corrected image 21 (see Fig. 6) for the correction plate, and the second obtaining unit 12 Can obtain the second rotated image 32 (see FIG. 7) and the second corrected image 22 (see FIG. 6) for the correction plate at different magnifications from the first obtaining unit 11. At this time, the first acquiring unit 11 and the second acquiring unit 12 may acquire the first rotation image 31 and the second rotation image 32 by continuously executing the N-times exposure at least twice , And the minimum value of the exposure interval (dt _min ) can be calculated through Equation (5).

Here, the first obtaining unit 11 and the second obtaining unit 12 may use a multiple exposure camera, and the first obtaining unit 11 and the second obtaining unit 12 may use a lens having a different magnification Images can be acquired. For example, the first acquiring unit 11 can acquire an image using a lens having a larger magnification than the second acquiring unit 12.

도로 설정할 수 있고, 제2 획득부(12)의 틸트 각도는 0도, 롤 각도는 0도, 팬 각도는

도로 설정할 수 있다.
6, the first acquiring unit 11 and the second acquiring unit 12 can be installed at a height of h meters from the batting seat 30, and the first acquiring unit 11 and the second acquiring unit 12 2 acquisition units 12 may be set to be g-meter. At this time, the tilt angle of the first obtaining unit 11 is set to 0 degrees and the roll angle is set to 0 degrees so that the directions of the first obtaining unit 11 and the second obtaining unit 12 face the center of the plate. 0 degrees, the pan angle is

The tilt angle of the second acquiring unit 12 is 0 degree, the roll angle is 0 degree, and the fan angle is

You can set the road.

The processing unit 13 calculates a correction matrix based on the first corrected image 21, the second corrected image 22, the position information on the first obtaining unit 11, and the position information on the second obtaining unit 12 And generates a reference position of the rotating body based on the correction matrix, the first rotation image 31, and the second rotation image 32. [

The processing unit 13 can generate correction information for the internal variable based on the first corrected image 21 and the second corrected image 22 and generates correction information for the internal variable based on the step S120 can do. That is, the processing unit 13 generates the correction information (K _r , K _l ) for the internal variable based on the information about the first corrected image 21 and the second corrected image 22 .

The processing unit 13 may generate correction information for an external variable based on the positional information on the first obtaining unit 11 and the positional information on the second obtaining unit 12. Based on the above described step S130 It is possible to generate correction information for an external variable. That is, the processing unit 13 calculates the positional information of the external variable through the equation (2) based on the positional information (i.e., the tilt angle, the roll angle, and the fan angle) of the first obtaining unit 11 and the second obtaining unit 12 It may generate the correction information _{(R r,} R _l).

The processing unit 13 may generate a correction matrix based on the correction information on the internal variable and the correction information on the external variable, and may generate the correction matrix on the basis of the above-described step S140. That is, the processing unit 13 may generate the correction matrix P _r , P _l through Equation (4).

The processing unit 13 can generate the two-dimensional position information of the rotating body based on the first rotating image 31 and the second rotating image 32. Based on the above-described step S310, Lt; / RTI > That is, the processing unit 13 can calculate the center point, diameter, and the like of the rotating body from the plurality of rotated images using image processing and computer vision techniques such as background removal and connection component labeling, area filtering, and a circle fitting technique.

The processing unit 13 obtains N rotator center points {X _r1 , ..., N _r ) from the first rotated image 31 in order of time. , X _rN } and the diameter D _r, and obtains N rotational center points {X _{l 1} , ..., X n} from the second rotated image 32 in order of time. , X _lN } and the diameter D _l . At this time, the processor 13 first rotating image 31 rotational center point in the X _r = (x _r, y _r) and the second rotating body in the rotating image 32 is the center point X _l = (x _l, y _l) The center point and the diameter of the rotating body can be calculated so as to satisfy Equation (6).

를 생성할 수 있다.The processing unit 13 can generate three-dimensional position information of the rotating body based on the correction matrix and the two-dimensional position information of the rotating body, and can generate three-dimensional position information of the rotating body based on the above-described step S320 . That is, the processing unit 13 obtains the correction matrix P _r for the first obtaining unit 11, the correction matrix P _l for the second obtaining unit 12, second time the center point of the entire _{x rn = (x rn, y} rn), the second rotating the n-th time the center point of the entire acquired from the image (32) x _ln = equation (7) based on the (x _ln, y _ln) The three-dimensional position information of the rotating body

Lt; / RTI >

The processing unit 13 can determine the three-dimensional position information whose difference from the two-dimensional position information in the three-dimensional position information of the rotating body satisfies a predetermined reference as the reference position of the rotating body. Based on the above-described step S330 The entire reference position can be determined. That is, the processing unit 13 obtains the reconstruction error corresponding to the difference between the position where the three-dimensional position information is projected on the first rotation image 31 and the two-dimensional position information (i.e., the center point) As shown in Equation (8), so that the reconstruction error corresponding to the difference between the position at which the first rotation image 32 is projected onto the second rotation image 32 and the two-dimensional position information (i.e., the center point) Dimensional position information (i.e., reference position) X _n , Y _n , Z of the rotating body that minimizes a normalized reconstruction error (NRCE) normalized through the entire diameter (D _r , D ₁ ) _n can be calculated through a nonlinear method.

로부터 회전체의 선속도

를 산출할 수 있다.The processing section 13 can calculate the linear velocity of the rotating body on the basis of the difference between the reference positions of the rotating body and calculate the linear velocity of the rotating body on the basis of the above step S400. That is, the processing unit 13 _obtains the positional change between the reference position X _s and X _e of the rotating body through Equation (11)

The linear velocity of the rotating body

Can be calculated.

The processing unit 13 can calculate the angular speed of the rotating body based on the rotation change between the reference positions of the rotating body. Specifically, the processing unit 13 can select the two-dimensional position information corresponding to the reference positions of the rotation image having a relatively high magnification among the first rotation image 31 and the second rotation image 32, The two-dimensional position information can be selected based on S410.

를 생성할 수 있다.The processing unit 13 can generate the two-dimensional candidate position information in which the error with respect to the center point of the rotating body is corrected based on the two-dimensional position information, and generate the two-dimensional candidate position information based on the step S420 . That is, the processing unit 13 _obtains the two-dimensional candidate position information of the rotating body which corrects the center point extraction error (d _rx , d _ry ) on the center point X _re (or X _rs )

Lt; / RTI >

The processing unit 13 can generate a rotation matrix based on the rotation variation whose error according to the image matching in the rotation variation according to the two-dimensional candidate position information satisfies a predetermined criterion. Based on the above-described step S430, Can be generated.

로 하여 상기 수학식 12와 같이 나타낼 수 있다.That is, the processing unit 13 applies a 3-dimensional rotation image-based three-dimensional image registration technique to the rotating body surface image within the radius d _r according to the two-dimensional position information X _rs , X _re , It is possible to calculate the rotation matrix dR according to the three-dimensional rotation variation of the rotation matrix dR. The rotation matrix dR of the rotating body

(12) " (12) "

을 산출할 수 있고, 이를 기초로 미리 결정된 기준을 만족하는 회전 변화에 따른 회전 행렬을 생성할 수 있다.Then, the processing unit 13 sets the normalized re-registration error (NRGE) normalized through the size A of the surface image matching area to a minimum value with d _rx and d _ry as additional parameters as shown in Equation (13)

And based on this, a rotation matrix according to a rotation change satisfying a predetermined criterion can be generated.

과

를 상기 수학식 26에 적용하여 회전체의 각속도를 산출할 수 있다.The processing unit 13 can calculate the angular velocity of the rotary body based on the rotation matrix and calculate the angular velocity of the rotary body based on the above-described step S440. That is, the processing unit 13 calculates the values

and

Can be applied to Equation (26) to calculate the angular velocity of the rotating body.

The functions performed by the processing unit 13 may be substantially performed by a processor (e.g., a CPU (Central Processing Unit) and / or a GPU (Graphics Processing Unit) Each step performed may be performed in the processor.

The methods according to the present invention can be implemented in the form of program instructions that can be executed through various computer means and recorded on a computer readable medium. The computer readable medium may include program instructions, data files, data structures, and the like, alone or in combination. The program instructions recorded on the computer readable medium may be those specially designed and constructed for the present invention or may be available to those skilled in the computer software. Examples of computer readable media include hardware devices that are specially configured to store and execute program instructions, such as ROM, RAM, flash memory, and the like. Examples of program instructions include machine language code such as those generated by a compiler, as well as high-level language code that can be executed by a computer using an interpreter or the like. The hardware devices described above may be configured to operate with at least one software module to perform the operations of the present invention, and vice versa.

The methods according to the present invention can be implemented in the form of program instructions that can be executed through various computer means and recorded on a computer readable medium. The computer readable medium may include program instructions, data files, data structures, and the like, alone or in combination. The program instructions recorded on the computer readable medium may be those specially designed and constructed for the present invention or may be available to those skilled in the computer software. Examples of computer readable media include hardware devices that are specially configured to store and execute program instructions, such as ROM, RAM, flash memory, and the like. Examples of program instructions include machine language code such as those generated by a compiler, as well as high-level language code that can be executed by a computer using an interpreter or the like. The hardware devices described above may be configured to operate with at least one software module to perform the operations of the present invention, and vice versa.

It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined in the appended claims. It will be possible.

10: Rotation characteristic measuring device
11:
12; The second obtaining unit
13:

Claims (12)

A method of measuring a rotation characteristic of a rotating body performed in an apparatus for measuring rotation characteristics of a rotating body,
Generating a correction matrix based on correction information on an internal variable of the measurement apparatus and correction information on an external variable;
Obtaining a plurality of rotated images for the rotating body according to different magnifications; And
And generating reference positions of the rotator based on position information of the correction matrix and the plurality of rotation images. The method of claim 1, wherein generating the correction matrix comprises:
Obtaining a plurality of correction images for the correction plate according to different magnifications;
Generating correction information for the internal variable based on the plurality of corrected images;
Generating correction information for the external variable based on position information of the measurement device; And
And generating the correction matrix based on correction information on the internal variable and correction information on the external variable. The method of claim 1, wherein generating the reference positions of the rotor comprises:
Generating two-dimensional position information of the rotating body on the basis of the plurality of rotated images;
Generating three-dimensional position information of the rotating body based on the correction matrix and the two-dimensional position information of the rotating body; And
And determining three-dimensional position information, which is a difference between the three-dimensional position information of the rotating body and the two-dimensional position information, satisfying a predetermined reference as a reference position of the rotating body. 2. The method according to claim 1,
And calculating a linear velocity of the rotating body based on a difference between reference positions of the rotating body. 2. The method according to claim 1,
And calculating an angular velocity of the rotating body based on a change in rotation between reference positions of the rotating body. 6. The method according to claim 5, wherein the step of calculating the angular velocity of the rotating body comprises:
Selecting two-dimensional position information corresponding to reference positions of a rotation image having a relatively high magnification among the plurality of rotation images;
Generating two-dimensional candidate position information in which an error with respect to a center point of the rotating body is corrected based on the two-dimensional position information;
Generating a rotation matrix based on a rotation change in which an error according to the image matching among the rotation changes according to the two-dimensional candidate position information satisfies a predetermined criterion; And
And calculating an angular velocity of the rotating body based on the rotation matrix. A first acquiring unit acquiring a first rotation image for the rotation body and a first correction image for the correction plate;
A second acquiring unit acquiring a second rotated image of the rotating body and a second corrected image of the compensating plate at a magnification different from that of the first acquiring unit; And
Wherein the correction matrix generating unit generates a correction matrix based on the first correction image, the second correction image, the position information on the first obtaining unit, and the position information on the second obtaining unit, And a processing unit for generating a reference position of the rotating body on the basis of the second rotation image. The image processing apparatus according to claim 7,
Wherein the correction information generating unit generates correction information for an internal variable based on the first correction image and the second correction image and generates correction information for an internal variable based on the position information for the first obtaining unit and the position information for the second obtaining unit, And generates the correction matrix based on the correction information on the internal variable and the correction information on the external variable. The image processing apparatus according to claim 7,
Dimensional position information of the rotating body on the basis of the first rotating image and the second rotating image and generates three-dimensional position information of the rotating body based on the correction matrix and the two-dimensional position information of the rotating body And determining three-dimensional position information of the three-dimensional position information of the rotating body, the three-dimensional position information having a difference between the three-dimensional position information and the two-dimensional position information satisfying a predetermined reference, as a reference position of the rotating body. The image processing apparatus according to claim 7,
And calculating a linear velocity of the rotating body based on a difference between reference positions of the rotating body. The image processing apparatus according to claim 7,
Wherein the angular velocity of the rotating body is calculated based on a change in rotation between reference positions of the rotating body. 12. The apparatus of claim 11,
Dimensional position information corresponding to reference positions of a rotation image having a relatively high magnification among the first rotation image and the second rotation image, based on the two-dimensional position information, Dimensional candidate position information, and generates a rotation matrix based on a rotation variation whose error according to the image matching satisfies a predetermined criterion in the rotation variation according to the two-dimensional candidate position information, And the angular velocity of the rotating body is calculated on the basis of the angular velocity of the rotating body.

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