JP2021032779A - Length measuring device - Google Patents

Abstract

To enable the error of computed length of a measurement object to be reduced.SOLUTION: A length measuring device comprises: a first image sensor 3 for detecting an edge position on one side of measurement face fronting on a tabular measurement face; a second image sensor 4, fronting on one face that indicates thickness, for detecting the position of an edge on one side, the imaging direction of which approximately intersects the first image sensor at right angles; a third image sensor 5, fronting on the measurement face, for detecting the position of an edge on the side opposite the one side of the measurement face; a fourth image sensor 6, fronting on the other face that indicates thickness on the side opposite the one face that indicates thickness, for detecting the position of an edge on the opposite side, the imaging direction of which approximately intersects the third image sensor at right angles; and a computation unit for calculating the position of an edge 2R on one side of a measurement object on the basis of the position of edge on the one side detected by the first and second image sensors, as well as calculating the position of an edge on the opposite side of the measurement object on the basis of the position of an edge 2L on the opposite side detected by the third and fourth sensors, and calculating the length of the measurement object that includes the edge on the one side and the edge on the other side.SELECTED DRAWING: Figure 2

Description

Embodiments of the present invention relate to a length measuring device.

Conventionally, in the rolling process of a steel sheet which is a metal sheet, the edges on both sides in the direction orthogonal to the transport direction (hereinafter referred to as the width direction) of the rolled long steel sheet are imaged from above with two cameras respectively. A length measuring device for measuring the length of a steel sheet in the width direction by extracting the end portion of the steel sheet from an captured image is known.

In this length measuring device, the actual length of the steel sheet in the width direction is calculated by grasping the correspondence between the pixel address of the camera (the address indicating the position of the light receiving element) and the distance to the steel sheet in advance. Was adopted.

In this case, each of the two cameras is arranged side by side in the width direction of the steel plate, and when the steel plate is conveyed, each edge is viewed in stereo by the two cameras to measure the steel plate to be measured. When the lift from the transport table occurred, the lift was corrected.

Japanese Unexamined Patent Publication No. 2008-128756

As a result of performing this lift correction, the length of the steel sheet in the width direction contained a certain error. Then, as the distance between the camera and the edge of the steel sheet to be conveyed in the width direction increases, the error that occurs in the calculated length of the steel sheet in the width direction tends to increase considerably. For example, when the distance between the camera and the edge is 1200 mm, an error of up to 0.7 mm occurs in the calculated length of the steel plate.

The present invention has been made in view of the above, and an object of the present invention is to provide a length measuring device capable of alleviating an error in the length of a calculated object to be measured.

The length measuring device of the embodiment is arranged at a position facing the measurement surface of the measurement target in a plate shape, and has a first image sensor that detects the position of an edge on one side of the measurement surface and a thickness of the measurement target. The second image sensor is arranged at a position facing the indicated one surface, the imaging direction is substantially orthogonal to the first image sensor, and the second image sensor for detecting the position of the edge on one side is arranged at a position facing the measurement surface of the measurement target. At a position facing the third image sensor that detects the position of the edge of the measurement surface on the side opposite to the one side and the other surface that indicates the thickness on the side opposite to the one surface that indicates the thickness of the measurement target. A fourth image sensor that is arranged and whose imaging direction is substantially orthogonal to the third image sensor and detects the position of the opposite edge, and the one side detected by the first image sensor and the second image sensor. The position of the edge on one side of the measurement target is calculated based on the position of the edge, and the measurement is performed based on the position of the opposite edge detected by the third image sensor and the fourth image sensor. It is provided with a calculation unit that calculates the position of the edge on the opposite side of the target and calculates the length of the measurement target including the edge on the one side and the edge on the opposite side.

FIG. 1 is a diagram showing the entire length measuring device according to the embodiment in the embodiment. FIG. 2 is an explanatory diagram showing the arrangement relationship of the length measuring device. FIG. 3 is an explanatory diagram for calculating the edge on one side of the steel sheet. FIG. 4 is a graph showing a graph of the relationship between the distance (Wds) from the camera to the edge of the steel plate and its error (ΔWds). FIG. 5 is an explanatory diagram for calculating the edge on the other side of the steel sheet. FIG. 6 is a block diagram showing a hardware configuration of the calculation unit. FIG. 7 is a flowchart showing a length measurement process of the steel sheet in the width direction by the calculation unit 20.

Hereinafter, the length measuring device of the embodiment will be described with reference to the drawings. The invention is not limited to this embodiment.

FIG. 1 is an explanatory diagram of an embodiment in a case where the length measuring device is applied to steel plate transportation and configured as a steel plate length measuring system.

The length measuring system 10 is roughly divided into a steel plate conveying device 11 for conveying a long steel plate 2 (measurement target) rolled flat by a rolling apparatus (not shown) and a steel plate conveyed by the steel plate conveying device 11. It is provided with a length measuring device 13 that captures an image of 2 and measures the length while correcting the lift of the conveyed steel plate 2, and a calculation unit 20 that calculates the edge of the steel plate 2.

In the steel plate transfer device 11, a plurality of rotating transfer rollers 1 are arranged in parallel at equal intervals in the transfer direction of the steel plate 2 (direction of arrow Y2). Each transport roller 1 is rotated in the same direction by a power source (not shown) to transport the steel plate 2 in the transport direction.

The length measuring device 13 includes a camera 3 (first image sensor), a camera 4 (second image sensor), a camera 5 (third image sensor), a camera 6 (fourth image sensor), a first light source 7, and a second. A light source 8 and a third light source 9 are provided. The camera 3 is installed above the steel plate 2, that is, at a position facing the upper surface 2-1 (measurement surface) of the steel plate 2. The camera 3 is an image sensor in which light receiving elements are arranged in a row in the width direction (arrow Y1 direction) of the steel plate 2. That is, the image pickup direction of the camera 3 is the width direction of the steel plate 2 (that is, the arrow Y1 direction). The camera 3 images the upper surface of the steel plate 2 in the vertical direction from above to below. The camera 3 takes an image of the upper surface 2-1 of the steel plate 2 including the right edge 2R, which is one edge. The camera 3 transmits video information indicating the captured image to the calculation unit 20 described later. The camera 4 is installed at a position facing the side surface 2-2 (one surface indicating the thickness) of the steel plate 2 including the right side edge 2R which is one edge of the steel plate 2. The camera 4 is an image sensor in which light receiving elements are arranged in a row in the thickness direction of the steel plate 2 (that is, in the vertical direction (arrow Y3 direction)). That is, the image pickup direction of the camera 4 is the thickness direction of the steel plate 2 (that is, the vertical direction (arrow Y3 direction)). That is, the camera 4 is located on the side of the steel plate 2 on the right side edge 2R side and below the right side edge 2R (in the direction opposite to the upper surface 2-1), and images the steel plate 2 including the right edge 2R. .. The camera 4 transmits video information indicating the captured image to the calculation unit 20 described later.

The camera 5 is installed above the steel plate 2, that is, at a position facing the upper surface 2-1 (measurement surface) of the steel plate 2. The camera 5 is an image sensor in which light receiving elements are arranged in a row in the width direction (arrow Y1 direction) of the steel plate 2. That is, the image pickup direction of the camera 5 is the width direction of the steel plate 2 (that is, the arrow Y1 direction). The camera 5 takes an image of the steel plate 2 in the vertical direction from above to below. The camera 5 takes an image of the steel plate 2 including the left edge 2L, which is the edge on the other side. The camera 5 transmits video information indicating the captured image to the calculation unit 20 described later. The camera 6 is installed at a position facing the side surface 2-3 (another surface indicating the thickness) of the steel plate 2 including the left side edge 2L which is the opposite edge of the steel plate 2. The camera 6 is an image sensor in which light receiving elements are arranged in a row in the thickness direction (that is, the vertical direction) of the steel plate 2. That is, the image pickup direction of the camera 6 is the thickness direction of the steel plate 2 (that is, the vertical direction (arrow Y3 direction)). That is, the camera 6 is located on the side of the left side edge 2L side of the steel plate 2 and below the left side edge 2L (in the direction opposite to the upper surface 2-1), and the upper surface 2 of the steel plate 2 including the left side edge 2L. -1 is imaged. The camera 6 transmits video information indicating the captured image to the calculation unit 20 described later.

The first light source 7 is arranged vertically below the steel plate conveying device 11 and below (far) from the camera 4 and the camera 6. The first light source 7 includes a light source in which light emitting elements are arranged in a row in the width direction of the steel plate 2 on the upper surface. When the light source emits light, the first light source 7 emits light from the lower side of the steel plate 2 toward the upper side in the vertical direction. The light emitted from the first light source 7 and not blocked by the steel plate 2 is received by the camera 3 and the camera 5. Further, the light emitted from the first light source 7 and blocked by the steel plate 2 is not received by the camera 3 and the camera 5. That is, among the light receiving elements provided in the camera 3 and the camera 5, the light receiving element at the position facing the steel plate 2 does not receive the light emitted from the first light source 7. That is, the video information output from the camera 3 and the camera 5 becomes a dark level signal by the width of the steel plate 2, and falls or rises at the positions of the right edge 2R and the left edge 2L of the steel plate 2.

Here, by associating (calibrating) the pixel address of the light receiving element with the scale of the steel plate 2 in the camera 3, the calculation unit 20 described later can use the steel plate from the rising address and falling address of the light receiving element. The right edge 2R of 2 can be calculated.

Further, in the camera 5, by associating (calibrating) the pixel address of the light receiving element with the scale of the steel plate 2, the left edge 2L of the steel plate 2 is calculated from the rising address and falling address of the light receiving element. be able to. The camera 3 and the camera 5 transmit information received by the light receiving element (information on which light receiving element receives light and which light receiving element does not receive light) as video information to the calculation unit 20 described later. To do.

The second light source 8 is installed on the right edge 2R side of the steel plate 2 to be conveyed. The second light source 8 includes a light source in which light emitting elements are arranged in a row in the vertical direction. The second light source 8 emits light obliquely downward toward the side surface including the right edge 2R of the steel plate 2. The light emitted from the second light source 8 and reflected by the side surface of the steel plate 2 is received by the camera 4. On the other hand, the light emitted from the second light source 8 and not reflected by the side surface of the steel plate 2 is not received by the camera 4.

The third light source 9 is installed on the left edge 2L side of the steel plate 2 to be conveyed. The third light source 9 includes a light source in which light emitting elements are arranged in a row in the vertical direction. The third light source 9 emits light obliquely downward toward the side surface including the left side edge 2L of the steel plate 2. The light emitted from the third light source 9 and reflected by the side surface of the steel plate 2 is received by the camera 5. On the other hand, the light emitted from the third light source 9 and not reflected by the side surface of the steel plate 2 is not received by the camera 5.

The wavelength of the light emitted from the second light source 8 and the third light source 9 is shorter than the wavelength of the light emitted from the first light source. Then, a filter (not shown) for cutting short wavelengths of light emitted from the second light source 8 and the third light source 9 is attached to the camera 3 and the camera 5 in front of the image sensor. By doing so, the camera 3 and the camera 5 receive the light emitted from the first light source 7, but do not receive the light emitted from the second light source 8 and the third light source 9.

The arithmetic unit 20 is configured as a so-called computer system, and includes a computer main body including a CPU, ROM, RAM, an external storage device (SSD, hard disk, etc.), a display unit, a printer, and the like. The arithmetic unit 20 is electrically connected to the camera 3, the camera 4, the camera 5, and the camera 6 via the communication line P. The calculation unit 20 receives the video information captured by the camera 3, the camera 4, the camera 5, and the camera 6. The calculation unit 20 calculates the position information of the right side edge 2R and the left side edge 2L of the steel plate 2 based on these video information, and calculates the length of the steel plate 2 in the width direction based on the position information.

FIG. 2 is an explanatory diagram showing the arrangement relationship of the length measuring device 13. Note that FIG. 2 is a view of the length measuring device 13 of FIG. 1 as viewed from the downstream side in the transport direction. Further, in FIG. 2, the width direction (horizontal direction in FIG. 2) is defined as the x-axis coordinate and the vertical direction (vertical direction in FIG. 2) is defined as the y-axis coordinate centered on the origin (0,0). The camera 3 and the camera 5 are arranged above the steel plate 2 to be conveyed at the same height from the steel plate 2. The distance between the camera 3 and the camera 5 is L. The origin exists at a position directly below the midpoint between the camera 3 and the camera 5 (the position at a distance of L / 2 from both the camera 3 and the camera 5). The steel plate 2 is transported in the transport direction with the midpoint between the camera 3 and the camera 5 being substantially in the center of the steel plate 2.

The camera 3 has a calibration position at a position at a distance a in the vertical direction from the camera 3. The camera 5 has a calibration position at a position at a distance a in the vertical direction from the camera 5. That is, the calibration position of the camera 3 and the calibration position of the camera 5 are at the same height in the vertical direction. Further, the origin is a calibration position separated from the midpoint between the camera 3 and the camera 5 by a distance a directly below in the vertical direction. Both the calibration position of the camera 3 and the calibration position of the camera 5 are located below the transport position of the steel plate 2. The calibration position is a position for recognizing an image captured by the camera.

The camera 4 is located outside the width direction by a distance Ld from the camera 3 and is arranged on the calibration position of the camera 3. That is, the camera 4 is arranged below the steel plate 2.

The camera 6 is located outside the width direction by a distance Lw from the camera 5 and is arranged on the calibration position of the camera 5. That is, the camera 6 is arranged below the steel plate 2.

The length W of the steel plate 2 in the width direction is set shorter than the distance L between the camera 3 and the camera 5. The camera 3 is located outside the width direction (right side in FIG. 2) by a distance Wds from the position of the right edge 2R of the steel plate 2. Further, the camera 5 is located on the outer side in the width direction (left side in FIG. 2) by a distance Wws from the left side edge 2L of the steel plate 2.

The calibration position of the camera 4 is set to a vertically downward position of the camera 3. That is, the camera 3 is arranged above the vertical line of the calibration position of the camera 4. The calibration position of the camera 4 is located outward by Wds from the right edge 2R of the steel plate 2 in the width direction.

Further, the calibration position of the camera 6 is set to a vertically downward position of the camera 5. That is, the camera 5 is arranged above the vertical line of the calibration position of the camera 6. The calibration position of the camera 6 is located outward by Wws from the left edge 2L of the steel plate 2 in the width direction.

The light emitted upward from the first light source 7 is received by the camera 3 or the camera 5. Of the light emitted from the first light source 7, the light outside the light KR that has passed through the right edge 2R is received by the camera 3. Further, among the light emitted from the first light source 7, the light outside the light KL that has passed through the left edge 2L is received by the camera 5. However, of the light emitted from the first light source 7, the light inside the light KR and the light KL is blocked by the steel plate 2 and is not received by the camera 3 or the camera 5.

Further, among the light emitted obliquely downward from the second light source 8, the light SR reflected by the right edge 2R of the steel plate 2 is received by the camera 4. However, among the light emitted from the second light source 8, the light passing outside the right edge 2R of the steel plate 2 (upper side in FIG. 2) is not reflected by the steel plate 2 and is not received by the camera 4. In this case, the right edge 2R is located on the upper surface of the steel plate 2.

Further, among the light emitted obliquely downward from the third light source 9, the light SL reflected by the left edge 2L of the steel plate 2 is received by the camera 6. However, among the light emitted from the third light source 9, the light passing outside the left side edge 2L of the steel plate 2 (upper side in FIG. 2) is not reflected by the steel plate 2 and is not received by the camera 6. In this case, the left edge 2L is located on the upper surface of the steel plate 2.

The steel sheet 2 emits natural light (self-luminous) by itself when the temperature is high. When the steel plate 2 emits light by itself, the camera 3, the camera 4, the camera 5, and the camera 6 receive the self-light receiving from the steel plate 2 even without the first light source 7, the second light source 8, and the third light source 9. Then, the same video information as the video information associated with the reception of the light emitted by the first light source 7, the second light source 8, and the third light source 9 can be transmitted to the arithmetic unit 20.

Next, a step of calculating the coordinates of the right edge 2R by the calculation unit 20 based on the video information accompanying the imaging by the camera 3 and the camera 4 will be described. FIG. 3 is an explanatory diagram for calculating the right edge 2R of the steel plate 2.

First, the position Pd of the camera 3 is such that the camera 3 is separated from the origin by a distance L / 2 in the x-axis direction and is separated from the origin by a distance a in the y-axis direction. Therefore, the coordinate position of the camera 3 is Pd. (L / 2, a). Further, the camera 3 measures the right edge 2R of the steel plate 2 at the calibration position Qd of the camera 3. The calibration position Qd of the camera 3 is Qd (L / 2-Wdc, 0). Further, since the position Rd of the camera 4 is located on the x-axis separated by a distance L / 2 + Ld in the x-axis direction, the coordinate position of the camera 4 is Rd (L / 2 + Ld, 0). Further, the camera 4 measures the right edge 2R of the steel plate 2 at the calibration position Sd of the camera 4. The calibration position Sd of the camera 4 is Sd (L / 2, hd). The coordinates Ed (xd, yd) of the right edge 2R where the extension lines of the line segment Pd-Qd (the line segment connecting the coordinates Pd and the coordinates Qd) and the line segment Rd-Sd (the line segment connecting the coordinates Rd and the coordinates Sd) intersect. ), Let Xd be the distance on the x-coordinate from the origin to the coordinate xd, and let Yd be the distance on the y-coordinate from the origin to the coordinate yd.
(Number 1)
Yd-a = (Xd-L / 2) · a / Wdc ... (1)
(Number 2)
Yd = (Xd-L / 2-Ld) · hd / Ld ... (2)
Will be. Substituting equation (1) into equation (2)
(Number 3)
(Xd-L / 2-Ld) · hd / Ld-a = (Xd-L / 2) · a / Wdc ... (3)
Will be. Solving equation (3) for Xd
(Number 4)
Xd = [(L / 2 + Ld) · hd / Ld + a−L / 2 · a / Wdc] / (hd / Ld-a / Wdc)… (4)
Will be. The position of the distance Xd in the x-axis direction from the origin is the x-coordinate (xd) of the coordinates Ed (xd, yd). By substituting Xd obtained by the formula (4) into the formula (1) or the formula (2), the distance Yd can be obtained. The position of the distance Yd in the y-axis direction from the origin is the y-coordinate (yd) of the coordinates Ed (xd, yd). Then, since Xd = L / 2-Wds, when substituted into the equation (4),
(Number 5)
L / 2-Wds = [(L / 2 + Ld) · hd / Ld + a−L / 2 · a / Wdc] / (hd / Ld-a / Wdc)… (5)
Will be. Solving this equation for Wds
(Number 6)
Wds = L / 2-[(L / 2 + Ld) · hd / Ld + a−L / 2 · a / Wdc] / (hd / Ld-a / Wdc)… (6)
Will be. By the way, in the equation (6), when the error ΔWdc is included in Wdc and the error Δhd is included in hd, the error ΔWds of Wds can be expressed.
(Number 7)
Wds + ΔWds = L / 2-[(L / 2 + Ld) · (hd + Δhd) / Ld + a−L / 2 · a / (Wdc + ΔWdc)] / [hd / Ld−a / (Wdc + ΔWdc)]… (7)
Will be. Solving this equation for ΔWds
(Number 8)
ΔWds = L / 2-[(L / 2 + Ld) · (hd + Δhd) / Ld + a−L / 2 · a / (Wdc + ΔWdc)] / [hd / Ld−a / (Wdc + ΔWdc)] −Wds… (8)
Will be. Regarding this equation (8), the relationship between Wds and ΔWds when the errors ΔWdc and Δhd are used as parameters is shown in FIG.

FIG. 4 is a graph showing a graph of the relationship between the distance (Wds) from the camera 3 to the right edge 2R of the steel plate 2 and the error (ΔWds) included in the distance (Wds). In this graph, for example, when an error of ± 0.1 mm occurs between ΔWdc and Δhd, and when the distance between the camera 3 and the right edge 2R is 1200 mm, the error ΔWds is ± 0.24 mm. That is, even if the distance (Wds) from the camera 3 to the right edge 2R of the steel plate 2 becomes large, the error ΔWds can be relaxed (reduced).

From here, the process of calculating the coordinates of the left edge 2L by the calculation unit 20 based on the video information accompanied by the imaging by the cameras 5 and 6 will be described. FIG. 5 is an explanatory diagram for calculating the left edge 2L of the steel plate 2.

First, the position Pw of the camera 5 is such that the camera 5 is separated from the x origin by a distance L / 2 in the axial direction and is separated by a distance a in the y-axis direction, so that the coordinate position of the camera 5 is Pw (-). L / 2, a). Further, the camera 5 measures the left edge 2L of the steel plate 2 at the calibration position Qw of the camera 5. The calibration position Qw of the camera 5 is Qw (−L / 2 + Wwc, 0). Further, since the position Rw of the camera 6 is located on the x-axis separated by a distance L / 2 + Lw in the x-axis direction, the coordinate position Rw of the camera 6 is Rw (−L / 2-Lw, 0). .. Further, the camera 6 measures the right edge 2R of the steel plate 2 at the calibration position Sw of the camera 6. The calibration position Sw of the camera 6 is Sw (−L / 2, hw). Coordinates Ew (xw, yw) on the left edge 2L where the extension lines of the line segment Pw-Qw (the line segment connecting the coordinates Pw and the coordinates Qw) and the line segment Rw-Sw (the line segment connecting the coordinates Rw and the coordinates Sw) intersect. ), Let Xw be the distance on the x-coordinate from the origin to the coordinate xw, and let Yw be the distance on the y-coordinate from the origin to the coordinate yw.
(Number 9)
Yw-a = (Xw-L / 2) ・ a / Wwc… (9)
(Number 10)
Yw = (Xw-L / 2-Lw) ・ hw / Lw… (10)
Will be. Substituting equation (9) into equation (10)
(Number 11)
(Xw-L / 2-Lw) ・ hw / Lw-a = (Xw-L / 2) ・ a / Wwc… (11)
Will be. Solving equation (11) for Xw
(Number 12)
Xw = [(L / 2 + Lw) ・ ww / Lw + a-L / 2 ・ a / Wwc] / (hp / Lw-a / Wwc)… (12)
Will be. The position of the distance Xw in the x-axis direction from the origin is the x-coordinate (xw) of the coordinates Ew (xw, yw). By substituting Xw obtained by the formula (12) into the formula (9) or the formula (10), the distance Yw can be obtained. The position of the distance Yw in the y-axis direction from the origin is the y-coordinate (yw) of the coordinates Ew (xw, yw). Then, since Xw = L / 2-Wws, when substituted into the equation (12),
(Number 13)
L / 2-Wws = [(L / 2 + Lw) · ww / Lw + a-L / 2 · a / Wwc] / (hw / Lw-a / Wwc) ... (13)
Will be. Solving this equation for Wws
(Number 14)
Wws = L / 2-[(L / 2 + Lw) · ww / Lw + a-L / 2 · a / Wwc] / (hw / Lw-a / Wwc) ... (14)
Will be. By the way, in the equation (14), when the error ΔWwc is included in Wwc and the error Δhw is included in hw, the error ΔWws of Wws is expressed.
(Number 15)
Wws + ΔWws = L / 2-[(L / 2 + Lw) · (hw + Δhw) / Lw + a−L / 2 · a / (Wwc + ΔWwc)] / [hp / Lw-a / (Wwc + ΔWwc)]… (15)
Will be. Solving this equation for ΔWws
(Number 16)
ΔWws = L / 2-[(L / 2 + Lw) · (hw + Δhw) / Lw + a−L / 2 · a / (Wwc + ΔWwc)] / [ww / Lw-a / (Wwc + ΔWwc)] −Wws… (16)
Will be. Regarding this equation (16), the relationship between Wws and ΔWws when the errors ΔWwc and Δhw are used as parameters is the same as the relationship between Wds and ΔWds shown in FIG. 4, and the left edge 2L of the steel plate 2 from the camera 5 Even if the distance to (Wws) becomes large, the error ΔWws can be relaxed (reduced).

The length W = Xd + Xw in the width direction of the steel plate 2. Then, in the case of Xd = Xw (that is, in the case of Xd = Xw = W / 2), the length values obtained by the equations (9) to (16) are the same as those of the equations (1) to (8). It is a value and can be obtained in the same manner as in the formulas (1) to (8) (that is, the values in the formulas (9) to (16) can be obtained by the formulas (1) to (8)). Then, the error ΔWds = ΔWws. Therefore, the error with respect to the length W in the width direction of the steel sheet 2 is ΔWds + ΔWws = 2ΔWds.

From here, the hardware of the arithmetic unit 20 will be described. FIG. 6 is a block diagram showing a hardware configuration of the calculation unit 20. As shown in FIG. 6, the arithmetic unit 20 includes a CPU (Central Processing Unit) 21, a ROM (Read Only Memory) 22, a RAM (Random Access Memory) 23, a memory unit 24, and the like. The CPU 21 is the control body. The ROM 22 stores various programs. The RAM 23 develops programs and various data. The memory unit 24 stores various programs. The CPU 21, ROM 22, RAM 23, and memory unit 24 are connected to each other via a bus 25. The CPU 21, ROM 22, and RAM 23 constitute the control unit 200. That is, the control unit 200 executes the control processing of the calculation unit 20, which will be described later, by operating the CPU 21 according to the control program stored in the ROM 22 or the memory unit 24 and expanded in the RAM 23.

The RAM 23 includes a camera 3 information unit 231 and a camera 4 information unit 232, a camera 5 information unit 233, and a camera 6 information unit 234. The camera 3 information unit 231 stores the video information received from the camera 3 based on the light received by the camera 3. The camera 4 information unit 232 stores the video information received from the camera 4 based on the light received by the camera 4. The camera 5 information unit 233 stores the video information received from the camera 5 based on the light received by the camera 5. The camera 6 information unit 234 stores the video information received from the camera 6 based on the light received by the camera 6.

The memory unit 24 is composed of an HDD (Hard Disc Drive), a flash memory, or the like, and maintains the stored contents even when the power supply is cut off. The memory unit 24 includes a control program unit 241. The control program unit 241 stores a control program for controlling the calculation unit 20.

The control unit 200 connects the operation unit 27 and the display unit 28 via the bus 25 and the controller 26. The operation unit 27 is a keyboard. The display unit 28 displays information toward the person who operates the calculation unit 20.

Further, the control unit 200 is connected to the communication interface (I / F) 29 via the bus 25. The communication interface 29 is connected to the camera 3, the camera 4, the camera 5, and the camera 6 via the communication line P. The communication interface 29 receives the video information received from the camera 3, the camera 4, the camera 5, and the camera 6.

Next, the control of the length calculation process of the steel plate 2 in the width direction by the calculation unit 20 will be described. FIG. 7 is a flowchart showing a length measurement process of the steel sheet in the width direction by the calculation unit 20. As shown in FIG. 7, the control unit 200 of the calculation unit 20 receives video information (that is, the image sensor of each camera) associated with the image captured by each camera from the camera 3, the camera 4, the camera 5, and the camera 6. (Video information based on optical information) is received via the communication line P (S11).

Next, the control unit 200 stores the video information received from each camera in the RAM 23 (S12). That is, the control unit 200 stores the video information received from the camera 3 in the camera 3 information unit 231. Further, the control unit 200 stores the video information received from the camera 4 in the camera 4 information unit 232. Further, the control unit 200 stores the video information received from the camera 5 in the camera 5 information unit 233. Further, the control unit 200 stores the video information received from the camera 6 in the camera 6 information unit 234.

Next, the control unit 200 calculates the position of the xy coordinate of the edge of the steel plate 2 based on the video information stored in the RAM 23 (S13). Specifically, the control unit 200 is based on the video information acquired from the camera 3 stored in the camera 3 information unit 231 and the video information acquired from the camera 4 stored in the camera 4 information unit 232. The coordinates Ed (xd, yd) of the right edge 2R of the steel plate 2 are calculated using the above equations (1) to (8). Further, the control unit 200 is based on the video information acquired from the camera 5 stored in the camera 5 information unit 233 and the video information acquired from the camera 6 stored in the camera 6 information unit 234. 9) The coordinates Ew (xw, yw) of the left edge 2L of the steel plate 2 are calculated using the equations (16). At that time, the error ΔWds included in the distance Wds used when calculating the coordinate xd and the error ΔWws included in the distance Wws used when calculating the coordinate xw are relaxed (the error is small). .. Therefore, more accurate coordinates xd and coordinates xw can be calculated.

Next, the control unit 200 calculates the length of the steel plate 2 in the width direction based on the calculated coordinates Ed (xd, yd) and coordinates Ew (xw, yw) (S14). That is, the control unit 200 calculates the length of the steel plate 2 in the width direction by calculating the distance between the coordinates xd and the coordinates xw on the x-axis. Then, the control unit 200 ends the process.

The length measuring device of such an embodiment detects the position of the right edge 2R on one side in the width direction of the steel plate 2 by an image sensor in which light receiving elements are arranged in a row in the width direction of the plate-shaped steel plate 2. The camera 4 detects the position of the right edge 2R of the steel plate 2 by the image sensor in which the light receiving elements are arranged in a row in the thickness direction of the side surface on one side of the steel plate 2, and the light is received in the width direction of the steel plate 2. The camera 5 that detects the position of the left side edge 2L on the other side of the steel plate 2 in the width direction by the image sensor in which the elements are arranged in a row, and the light receiving elements are arranged in a row in the thickness direction of the side surface on the other side of the steel plate 2. The position of the right edge 2R of the steel plate 2 is calculated based on the positions of the camera 6 that detects the position of the left edge 2L of the steel plate 2 and the right edge 2R detected by the camera 3 and the camera 4 by the image sensor. A calculation unit is provided which calculates the position of the left edge 2L of the steel plate 2 based on the position of the left edge 2L detected by the camera 5 and the camera 6 and calculates the length of the steel plate 2 in the width direction. Therefore, it is possible to alleviate an error in calculating the length of the steel plate 2 in the width direction.

The program executed by the length measuring system 10 (calculation unit 20) of the present embodiment is a file in an installable format or an executable format, and is a semiconductor memory device such as a CD-ROM or a USB memory, or a DVD (Digital Versaille Disk). ) Etc. are recorded on a computer-readable recording medium and provided.

Further, the program executed by the length measuring system 10 of the present embodiment may be stored on a computer connected to a network such as the Internet and provided by downloading via the network. Further, the program executed by the length measuring system 10 of the present embodiment may be configured to be provided or distributed via a network such as the Internet.

Further, the program of the length measuring system 10 of the present embodiment may be configured to be provided by incorporating it into a ROM or the like in advance.

Although the embodiment of the present invention has been described above, this embodiment is presented as an example and is not intended to limit the scope of the invention. This novel embodiment can be implemented in various other embodiments, and various omissions, replacements, and changes can be made without departing from the gist of the invention. This embodiment and its modifications are included in the scope and gist of the invention, and are also included in the scope of the invention described in the claims and the equivalent scope thereof.

1 Conveyor roller 2 Steel plate 2L Left edge 2R Right edge 3 Camera (1st image sensor)
4 camera (second image sensor)
5 Camera (3rd image sensor)
6 camera (4th image sensor)
7 1st light source 8 2nd light source 9 3rd light source 10 Measuring system 11 Steel plate transfer device 13 Measuring device 20 Calculation unit 200 Control unit 241 Control program unit P Communication line

Claims (6)

A plate-shaped first image sensor that is arranged at a position facing the measurement surface of the measurement target and detects the position of an edge on one side of the measurement surface, and a first image sensor.
A second image sensor, which is arranged at a position facing one surface indicating the thickness of the measurement target, has an imaging direction substantially orthogonal to the first image sensor, and detects the position of the edge on one side.
A third image sensor, which is arranged at a position facing the measurement surface of the measurement target and detects the position of an edge on the opposite side of the measurement surface to the one side.
It is arranged at a position facing the other surface indicating the thickness on the side opposite to the one surface indicating the thickness of the measurement target, the imaging direction is substantially orthogonal to the third image sensor, and the position of the edge on the opposite side is detected. With the 4th image sensor
The position of the edge on the one side of the measurement target is calculated based on the position of the edge on the one side detected by the first image sensor and the second image sensor, and the third image sensor and the fourth image sensor are calculated. The position of the opposite edge of the measurement target is calculated based on the position of the opposite edge detected by the image sensor, and the length of the measurement target including the one side edge and the opposite edge. The calculation unit that calculates the
A length measuring device equipped with. The calculation unit calculates an intersection of a straight line connecting the position of the edge on one side and the position of the first image sensor and a straight line connecting the position of the edge on the one side and the position of the second image sensor. The position of the edge on one side is calculated, and the straight line connecting the position of the edge on the opposite side and the position of the third image sensor, the position of the edge on the opposite side, and the position of the fourth image sensor are determined. Calculate the intersection of the straight lines to connect and calculate the position of the opposite edge.
The length measuring device according to claim 1. Facing the first image sensor and the third image sensor, the first image sensor and the third image sensor are provided farther from the second image sensor and the fourth image sensor, and the first image sensor and the third image sensor are provided. A first light source that emits light toward the third image sensor and light having a wavelength different from the light emitted from the first light source provided in the vicinity of the second image sensor are used to measure the thickness of the measurement target. A second light source that emits light toward one surface shown, and another surface that is provided in the vicinity of the fourth image sensor and has a wavelength different from the light emitted from the first light source and indicates the thickness of the measurement target. The first image sensor and the third image sensor include a third light source that emits light toward the surface, and the first image sensor and the third image sensor transmit the light emitted by the first light source, the light emitted by the second light source, and the second light source. The second image sensor includes a filter that blocks the light emitted by the three light sources, the second image sensor receives the light emitted from the second light source and reflected by the measurement target, and the fourth image sensor receives the light emitted from the third light source. Receives the light that is emitted and reflected by the measurement target.
The length measuring device according to claim 1 or 2. The angle of the second light source is adjusted so that the light emitted from the second light source is not received by the fourth image sensor, and the light emitted from the third light source is not received by the second image sensor. The angle of the third light source was adjusted.
The length measuring device according to claim 3. The first image sensor, the second image sensor, the third image sensor, and the fourth image sensor receive self-luminous light emitted by the measurement target at a high temperature.
The length measuring device according to claim 1 or 2. The position of the edge on one side and the edge on the opposite side are formed on the measurement surface of the measurement target, and the second image sensor is in the direction of one surface of the measurement target from the position of the edge on the one side. The fourth image sensor is arranged on the side opposite to the measurement surface, and the fourth image sensor is arranged on the side opposite to the measurement surface to be measured from the position of the edge on the opposite side.
The length measuring device according to claim 5.

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