Speed control device, conveyance control device, and conveyance control method

Abstract

To provide a technique capable of automatically shifting a moving object at a desired position.SOLUTION: A speed control device for controlling a moving speed of a moving object includes an object position grasping / tracking unit configured to detect and track, based on an image including the object, a tip end position of the object on the image, the tip end position being a tip end of the object when viewed from a moving direction of the object, and grasp a tip end position in a real space from the tip end position on the image, and a speed change command output unit configured to output a speed change command for the object when a position of the object grasped by the object position grasping / tracking unit reaches a desired designated position for performing a speed change of the object.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a speed control device for a moving object, such as hot steel, a transport control device for such an object, and a transport control method. [Background technology]

[0002] The transport and stopping of hot steel materials conveyed on conveyor rolls has traditionally been performed manually based on visual observation by an operator. However, there is a need for technology to automate this process. To achieve automation, a technology that automatically slows and stops the steel material at designated locations is essential. Therefore, automation using hot metal detectors (HMDs) has been considered (see, for example, Non-Patent Document 1). HMDs are radiation-type photoelectric sensors that directly detect infrared energy emitted from hot materials. HMDs are installed at key locations to monitor the area where the steel material passes. When the HMD turns on after the steel material passes, it issues a deceleration and stop command to the conveyor rolls transporting the steel material, stopping the steel material. This makes it possible to automatically decelerate and stop the steel material. Furthermore, technology using such HMDs can be used not only for slowing and stopping steel materials, but also for changing the speed of moving objects in general. [Prior art documents] [Non-patent literature]

[0003] [Non-Patent Document 1] Theory and Practice of Plate Rolling, Iron and Steel Institute of Japan, (2010), P278 Summary of the Invention [Problem to be solved by the invention]

[0004] However, the technology described in Non-Patent Document 1 is a technology that can only set the deceleration and stopping timing of the object, which is hot steel, at one specific point that the HMD is looking at, for example, at one point within a range of approximately Φ50 to 100 mm, and it is difficult to set the deceleration and stopping timing at an arbitrary point and decelerate and stop the object at a desired position.

[0005] Furthermore, the problem of not being able to change speed at a desired position arises not only when slowing down or stopping the hot steel material being transported, but also when changing the speed of a moving object. do.

[0006] Therefore, the present invention provides a technique that can automatically change the speed of a moving object at a desired position. [Means for solving the problem]

[0007] In order to solve the above problems, the present invention provides the following [1] to

[14] .

[0008] [1] A speed control device that controls the speed of a moving object, an object position grasping / tracking unit that detects and tracks a tip position on an image that is the tip of the object as seen from a moving direction of the object based on an image including the object, and grasps the tip position in real space from the tip position on the image; a speed change command output unit that outputs a speed change command for the object when the tip position of the object in real space grasped by the object position grasping / tracking unit reaches a desired designated position where a speed change of the object is to be performed; A speed control device having:

[0009] [2] The speed control device according to [1], wherein the speed change control is a deceleration control, and when the tip position of the object in real space reaches the designated position, a deceleration command is output as a speed change command for the object in order to stop the object at a desired position.

[0010] [3] The speed control device according to [2], wherein the specified position is one or two or more, and multi-stage deceleration is performed by specifying two or more positions.

[0011] [4] The object position recognition and tracking unit an object recognition unit that recognizes the object on the image; a tip position detection unit that detects the tip position on the image of the object recognized by the object recognition unit; an object position calculation unit that calculates a tip position of the object in real space from the tip position on the image detected by the tip position detection unit; The speed control device according to [1],

[0012] [5] The speed control device according to [4], wherein the tip position detection unit defines the tip position on the image by determining the distance from the pixels of the image after the image processing.

[0013] [6] A speed control device according to [4] or [5], wherein the object is hot steel that is red-hot and luminous, the object position grasping and tracking unit further has a binarization processing unit that binarizes the image, and the tip position detection unit detects the tip position on the image based on a change in brightness of the binarized image.

[0014] [7] A transport control device that controls transport of an object transported by a transport means, an imaging means for imaging a transport area of ​​the object being transported; a speed control device that controls a speed of the object to be conveyed based on the image captured by the imaging means; a drive control unit that controls the drive of the conveying means based on a speed control command from the speed control device; and The speed control device an object position grasping / tracking unit that detects and tracks a tip position that is a tip of the object when viewed from a moving direction of the object on the image based on an image including the object captured by the imaging means, and grasps the tip position in real space from the tip position on the image; a speed change command output unit that outputs a speed change command for the object when the tip position of the object in the real space grasped by the object position grasping / tracking unit reaches a desired position where a speed change of the object is performed; A transport control device having the above.

[0015] [8] The speed change control is a deceleration control, and a deceleration command is output as a speed change command for the object when the object reaches the specified position in order to stop the tip position of the object in real space at a desired position.

[0016] [9] The object positioning and tracking unit an object recognition unit that recognizes the object on the image; a tip position detection unit that detects the tip position on the image of the object recognized by the object recognition unit; an object position calculation unit that calculates a tip position of the object in real space from the tip position on the image detected by the tip position detection unit; The transport control device according to [7], having:

[0017]

[10] The object is hot steel that is red-hot and glowing, and the object position grasping / tracking unit further has a binarization processing unit that binarizes the image, and the tip position detection unit detects the tip position on the image based on a change in brightness of the binarized image. [9] A conveying control device as described in

[0018]

[11] A transport control method for controlling transport of an object transported by a transport means, comprising: taking an image of a transport area of ​​the object being transported; a step of recognizing the object from the captured image, detecting and tracking a tip position on the image that is the tip of the object when viewed from the direction of movement, and determining the tip position in real space from the tip position on the image; outputting a speed change command for the object when the tip position of the grasped object in real space reaches a designated position in real space where a speed change of the object is to be performed; a step of controlling a speed at which the object is conveyed by the conveying means based on the speed change command; A transport control method comprising:

[0019]

[12] A conveyance control method according to

[11] , wherein when the tip position of the object in real space reaches the specified position, a deceleration command is output as a speed change command for the object in order to stop the object at a desired position.

[0020]

[13] The process of detecting and tracking the tip position and determining the tip position in real space from the tip position on the image is performed by recognizing the object on the image, detecting the tip position on the image of the recognized object, and calculating the tip position of the object in real space from the tip position on the detected image.

[11] The transport control method described in

[11] .

[0021]

[14] The object is a hot steel material that is red-hot and luminous, and the process of detecting and tracking the tip position and determining the tip position in real space from the tip position on the image involves binarizing the image prior to recognizing the object, and detecting the tip position on the image of the object based on changes in brightness of the binarized image, in the conveying control method described in

[13] . [Effects of the Invention]

[0022] According to the present invention, the tip position of an object is grasped and tracked from an image including the object. Therefore, a wide field of view (e.g., several tens of meters) can be obtained by the angle of view of an imaging device, such as a camera, that captures the image, and a speed change point can be set at any position within that wide field of view. This allows the speed of a moving object to be automatically changed at a desired position. Furthermore, the wide field of view allows the object's speed to be changed at multiple points within that range. The technology of the present invention enables, for example, automatic deceleration and stopping of steel materials without manual operation, thereby improving work efficiency and labor savings through equipment automation. Furthermore, unlike the technology described in Non-Patent Document 1, which can only set the deceleration and stopping timing at a specific position viewed by the HMD, the technology allows the transported steel materials to be decelerated at any desired position within a wide range, thereby stopping the steel materials with precision. [Brief explanation of the drawings]

[0023] [Figure 1] 1 is a schematic configuration diagram showing a conveyance facility to which a conveyance control device equipped with a speed control device according to an embodiment is applied; [Figure 2] FIG. 2 is a block diagram showing a speed control device of the conveying equipment. [Figure 3] 1 is a flowchart showing a schematic flow of a method for controlling the transport of an object. [Figure 4] 10 is a flowchart showing a specific example of a control flow in a method for controlling the transport of an object. [Figure 5] 1 is a raw image of an H-beam moving straight along a line in an embodiment. [Figure 6] 6 is an image showing the state in which the position of the tip of the H-beam being transported is detected by processing the image of FIG. 5. [Figure 7] 10 is a diagram showing the change over time in the tip position when automatic deceleration and stopping are performed using the method of the embodiment. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0024] Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings.

[0025] <Conveying equipment> FIG. 1 is a schematic configuration diagram showing a conveyance facility to which a conveyance control device equipped with a speed control device according to one embodiment is applied, and FIG. 2 is a block diagram showing an example of a speed control device of the conveyance facility.

[0026] The conveying equipment 1 conveys an object 10 by a conveying means. In FIG. 1, arrow A indicates the movement direction (conveying direction) of the object 10. There are no particular restrictions on the object 10 as long as it is a moving object, and an example is steel. In this embodiment, an example is shown in which hot steel, which is an object that glows red hot, is used as the object 10. The conveying equipment 1 has a plurality of conveying rolls 2 as a conveying means, and a conveying control device 3 that controls the conveyance of the object 10.

[0027] The transport control device 3 has a camera 11 which is an imaging means, a speed control device 12, and a transport PLC 13 which is a drive control unit. The transport control device 3 is controlled by a higher-level process controller (not shown).

[0028] The camera 11, which is an imaging means, is used to capture an image of the area where the object 10 is being transported, i.e., the area where the object 10 is moving, and is installed so that a desired position where the speed of the object 10 is changed (described later), for example, a desired designated position where the object 10 is decelerated to stop, falls within the imaging field of view. The camera 11 may have an imaging element such as a CCD or CMOS. Generally, a camera has a wide field of view, for example, several tens of meters, depending on its angle of view, and can capture an image of the area where the object 10 is moving within that range.

[0029] The speed control device 12 controls the speed of the moving object 10, and specifically outputs a speed change command to the object 10 at a desired designated position in real space based on an image including the object 10 captured by the camera 11, which is an imaging means. The designated position is not limited to one, and may be multiple. That is, since the camera 11 has a wide field of view, multiple designated positions can be set within that range. For example, if the speed change control is a deceleration control to stop the object 10, as will be described later, deceleration commands can be output at multiple designated positions to perform multi-stage deceleration.

[0030] The transport PLC 13 sends a drive control signal to the transport rolls 2, which are driving means, based on a speed change command output from the speed control device 12, and controls the driving of the transport rolls 2.

[0031] An input device 31 is provided between the speed control device 12 and the camera 11, and an output device 32 is provided between the speed control device 12 and the conveying PLC 13. Images captured by the camera 11 are input to the speed control device 12 via the input device 31, and speed change commands from the speed control device 12 are sent to the conveying PLC 13 via the output device 32.

[0032] [Speed ​​control device] Next, the speed control device 12 will be described. As shown in FIG. 2, the speed control device 12 includes an object position recognition / tracking unit 21 and a speed change command output unit 22.

[0033] When an object enters the field of view of the camera 11, the object position grasping / tracking unit 21 grasps and tracks the leading edge position (leading edge position) of the object 10 on the image based on the image including the object 10, and calculates the leading edge position in real space from the leading edge position on the image. Note that the leading edge position is position 10a, which is the leading edge when viewed from the direction of arrow A, which is the movement direction, as shown in Figure 1.

[0034] In this example, an object 10 is an emitting object such as hot steel, and the object position grasping / tracking unit 21 has a binarization processing unit 23, an object recognition unit 24, a leading edge detection unit 25, and an object position calculation unit 26.

[0035] The binarization processing unit 23 acquires and binarizes the image captured by the camera 11. The binarization of the image in the binarization processing unit 23 is performed by converting a color image into a gray image, and for example, the following equation (1) is used (see OpenCV: Color conversions): RGB[A] to Gray: Y ← 0.299·R + 0.587·G + 0.114·B ···(1) The object recognition unit 24 recognizes that the object 10 has entered the field of view of the camera 11. The leading edge detection unit 25 detects the leading edge position on the image of the object 10 recognized by the object recognition unit 24. In this case, the leading edge detection unit 25 detects the edge on the image based on a change in brightness of the binarized image. The object position calculation unit 26 calculates the position of the object 10 in real space from the leading edge position on the image detected by the leading edge detection unit 25.

[0036] The object position calculation unit 26 defines the leading edge position in real space by, for example, determining the distance from the camera pixels after image processing. For example, if the right edge of the camera field of view is defined as 0 [mm] and the object 10 enters from the right edge of the camera field of view, the leading edge position α [mm] in real space when the right edge of the camera field of view is used as the reference is given by the following equation (2). α = zx × y (2) where x is the resolution [mm / pix], y is the pixel number [pix] at which the leading edge position in real space corresponds from the left edge of the camera's field of view, and z is the distance equivalent value of the left edge of the camera's field of view (camera field of view width) [mm].

[0037] The speed change command output unit 22 outputs a speed change command for the object 10 when the leading edge position in real space of the object 10 detected and tracked by the object position detection and tracking unit 21 reaches a desired specified position in real space. The speed change command for the object 10 may be a deceleration command for the object 10. For example, if the object 10 is a steel material, a deceleration command is output at the desired specified position in order to automatically stop the steel material at the desired position with high precision. As described above, the specified position is not limited to one, and there may be multiple positions. For example, when stopping the object 10, deceleration commands may be output at multiple specified positions to perform multi-stage deceleration and stop the object 10 at the desired position.

[0038] It should be noted that, for example, if the object 10 is not a light-emitting object such as hot steel, the binarization processing unit 23 is not essential.

[0039] <Transport control method> Next, a description will be given of a method for controlling the transport of an object by the transport control device 3. Fig. 3 is a flowchart showing a schematic flow of the method for controlling the transport of an object.

[0040] First, the transport area of ​​the object transported by the transport roll 2, which is the transport means, is imaged by the camera 11 (ST1).

[0041] Next, the object 10 is recognized from the captured image, and the object position recognition / tracking unit 21 detects and tracks the leading edge position of the object 10 on the image, and recognizes the leading edge position in real space from the leading edge position on the image (ST2).

[0042] Next, when the leading edge position of the object 10 in real space grasped by ST2 reaches a desired designated position where the speed of the object 10 is changed, a speed change command output unit 22 outputs a speed change command for the object 10 to the transport PLC 13 (ST3). For example, in order to stop a moving object at a desired position, a deceleration command is output when the leading edge position of the object 10 in real space reaches the desired designated position. Then, a speed change signal is output from the transport PLC 13 to the transport rolls 2, and the speed of the steel material is actually changed.

[0043] In this way, the leading edge position of object 10 on the image is grasped and tracked from an image including the moving object, so a wide field of view (for example, several tens of meters) can be obtained due to the angle of view of camera 11, which is the imaging means for capturing the image, and a speed change point can be set at any position within that wide field of view. This makes it possible to automatically change the speed of moving object 10 at a desired position. Furthermore, because of the wide field of view, multiple speed change points can be set within that range.

[0044] Next, a specific example of the control flow in such a conveyance control method will be described. Here, a case where hot steel, which is an object that emits light, is conveyed and automatically decelerated and stopped will be described. Figure 4 is a flowchart showing a specific example of the control flow in the object conveyance control method.

[0045] First, the camera 11 captures an image of a transport area for steel materials, which are objects transported by transport rolls 2, which are transport means (ST11).

[0046] Next, the object, the steel material, is recognized from the captured image, and the object position recognition / tracking unit 21 of the speed control device 12 detects and tracks the leading edge position of the object, the steel material, on the image, and recognizes the leading edge position in real space from the leading edge position on the image (ST12).

[0047] Specifically, in ST12, the binarization processing unit 23 binarizes the image (ST12-1), the object recognition unit 24 recognizes that a steel material as an object has entered the field of view of the camera (ST12-2), the leading edge detection unit 25 detects the leading edge position on the image, for example, from a change in brightness (ST12-3), and the object position calculation unit 26 calculates the leading edge position of the steel material in real space (ST12-4). At this time, the binarization of the image is performed, for example, by converting a color image into a gray image as described above, and the leading edge position in real space is detected using the above-mentioned equation (2).

[0048] Next, when the leading edge position of the steel material, which is the object grasped by ST12, reaches the desired designated position where the steel material is to be decelerated, a deceleration command for the object 10 is output from the speed change command output unit 22 to the transport PLC 13 (ST13). The designated position where the steel material is to be decelerated can be set by calculating backward from the desired position where the steel material is to be stopped.

[0049] Specifically, in this ST13, it is determined whether the leading edge position in real space of the steel material, which is the object, has reached a designated position in real space (ST13-1), and if it is determined that the steel material has reached the designated position in real space, a deceleration command is output to the transport PLC 13 (ST13-2). Then, a deceleration signal is output from the transport PLC 13 to the transport roll 2, and the steel material is actually decelerated.

[0050] Next, it is determined whether the number of times the deceleration command has been output has ended (ST14), and if it is determined that the number of times the deceleration command has been output has ended, the process ends.

[0051] In this example, the transport area for the steel material, which is the object being transported, is imaged using a camera (imaging device). The leading edge position in the image of the steel material is detected and tracked based on the captured image, and the leading edge position in real space is calculated from the leading edge position in the image. When the leading edge position in real space reaches a desired designated position in real space where the object is to be decelerated, a deceleration command is output, and the transport PLC 13 controls the transport of the steel material by the transport rolls 2 based on that command. Therefore, unlike the technology described in Non-Patent Document 1, which can only set the deceleration and stop timing at a specific position viewed by the HMD, this system can automatically decelerate the transported steel material at the desired position and stop the steel material with high precision. Furthermore, because the steel material is automatically decelerated and stopped, it is possible to improve work efficiency and reduce labor through equipment automation.

[0052] In addition, when transporting hot steel, which is an object that emits light, the image captured by the binary processing unit 23 is binarized, and the leading edge position on the image is detected by the leading edge detection unit 25 based on changes in brightness, thereby making it possible to clearly detect the leading edge position on the image and perform position detection with higher accuracy.

[0053] Although the embodiments of the present invention have been described above, these are merely examples and should not be considered limiting. The above embodiments may be omitted, substituted, or modified in various ways without departing from the spirit of the present invention.

[0054] For example, in the above embodiment, the present invention has been mainly described as being applied to the transportation of steel materials, particularly hot steel materials, but there are no particular limitations as long as the speed of a moving object is changed. Furthermore, the speed change control of an object is not limited to a case of decelerating the object, and may also be a case of increasing the speed.

[0055] Furthermore, the object position grasping / tracking unit 21 used in the present embodiment includes a binarization processing unit 23, an object recognition unit 24, a leading edge detection unit 25, and an object position calculation unit 26, but is not limited to this. Furthermore, the image processing and leading edge detection are not limited to binarizing the captured image and detecting the leading edge on the image based on changes in brightness. [Example]

[0056] Next, an embodiment of the present invention will be described. Here, we will explain the automatic deceleration and stopping of H-beams, which are hot steel products being transported on a line. Figure 5 shows a raw image of an H-beam moving straight along the line. Figure 6 shows the state after processing the image in Figure 5 to detect the leading edge position of the H-beam being transported. The "mask area" in Figure 6 is an area set in advance to exclude from the measurement area any obstructions to the field of view, such as handrails. The "measurement area" is the area in which the leading edge position of the steel product (H-beam) is measured. Since the line along which the steel product passes is predetermined, the measurement area is set on the line along which the steel product passes, and image processing is performed only within the measurement area. Furthermore, the "detected leading edge position" is obtained by searching for the leftmost point (direction of travel) based on the brightness change within the measurement area and drawing a line vertically from that position. Position calculations are performed using the leftmost coordinate.

[0057] Using the method described in the above embodiment, an H-beam moving straight along a line was automatically decelerated and stopped. Figure 7 shows the change in the tip position over time during this process. Here, the tip edge position on the vertical axis represents the detected tip position when the right edge of the camera's field of view is defined as 0 mm and the left edge as 6800 mm, for a steel beam moving straight from right to left. Here, the target stop position was set to 6700 mm, and the beam was stopped using two stages of deceleration. The first deceleration command (1.5 m / s → 0.5 m / s) was issued 3000 mm before the target stop position (3700 mm), and the second deceleration command (0.5 m / s → 0 m / s) was issued 200 mm before the target stop position (6500 mm). The resulting stop position was 6741 mm. In contrast, with the conventional method using an HMD, the deceleration is performed at a specific point that the HMD is looking at, and it is not possible to decelerate at the desired position, so it was confirmed that the stopping position is off by 100 mm or more. From these results, it was confirmed that the method of the above embodiment can decelerate the H-beam at the desired position, improving the stopping accuracy of the H-beam, which is a steel material. [Explanation of symbols]

[0058] 1. Transport equipment 2. Transport roll (transport means) 3. Transport control device 10 objects 11 Camera (imaging means) 12 Speed ​​control device 13 Transport PLC 21 Object location and tracking unit 22 Speed ​​change command output section 23 Binarization processing section 24 Object recognition section 25 Leading edge detection unit 26 Object position calculation section

Claims

1. A speed control device that controls the speed of a moving object, an object position grasping / tracking unit that detects and tracks a tip position on an image that is a tip of the object as seen from a moving direction of the object based on an image including the object, and grasps the tip position in real space from the tip position on the image; a speed change command output unit that outputs a speed change command for the object when the tip position of the object in real space grasped by the object position grasping / tracking unit reaches a desired designated position where a speed change of the object is to be performed; A speed control device having:

2. 2. The speed control device according to claim 1, wherein the speed change control is a deceleration control, and when the tip position of the object in real space reaches the designated position, a deceleration command is output as a speed change command for the object in order to stop the object at a desired position.

3. 3. The speed control device according to claim 2, wherein the specified position is one or more, and multi-stage deceleration is performed by specifying two or more specified positions.

4. The object position recognition and tracking unit an object recognition unit that recognizes the object on the image; a tip position detection unit that detects the tip position on the image of the object recognized by the object recognition unit; an object position calculation unit that calculates a tip position of the object in real space from the tip position on the image detected by the tip position detection unit; The speed control device of claim 1 , further comprising:

5. The speed control device according to claim 4 , wherein the tip position detection unit defines the tip position on the image by determining a distance from pixels of the image after the image processing.

6. 6. A speed control device according to claim 4, wherein the object is hot steel that is red-hot and luminous, the object position grasping and tracking unit further has a binarization processing unit that binarizes the image, and the tip position detection unit detects the tip position on the image based on a change in brightness of the binarized image.

7. A transport control device that controls transport of an object transported by a transport means, an imaging means for imaging a transport area of ​​the object being transported; a speed control device that controls a speed of the object to be conveyed based on the image captured by the imaging means; a drive control unit that controls the drive of the conveying means based on a speed control command from the speed control device; and The speed control device an object position grasping / tracking unit that detects and tracks a tip position of the object in the image, the tip position being a tip of the object as seen from the moving direction of the object, based on an image including the object captured by the imaging means, and grasps the tip position in real space from the tip position on the image; a speed change command output unit that outputs a speed change command for the object when the tip position of the object in the real space grasped by the object position grasping / tracking unit reaches a desired position where a speed change of the object is to be performed; A transport control device having the above.

8. 8. The transport control device according to claim 7, wherein the speed change control is a deceleration control, and when the object reaches the designated position, a deceleration command is output as a speed change command for the object in order to stop the tip position of the object in real space at a desired position.

9. The object position recognition and tracking unit an object recognition unit that recognizes the object on the image; a tip position detection unit that detects the tip position on the image of the object recognized by the object recognition unit; an object position calculation unit that calculates a tip position of the object in real space from the tip position on the image detected by the tip position detection unit; The transport control device according to claim 7 , further comprising:

10. 10. The transport control device according to claim 9, wherein the object is hot steel that is red-hot and luminous, the object position grasping / tracking unit further has a binarization processing unit that binarizes the image, and the tip position detection unit detects the tip position on the image based on a change in brightness of the binarized image.

11. A transport control method for controlling transport of an object transported by a transport means, comprising: taking an image of a transport area of ​​the object being transported; a step of recognizing the object from the captured image, detecting and tracking a tip position on the image that is the tip of the object when viewed from the direction of movement, and determining the tip position in real space from the tip position on the image; outputting a speed change command for the object when the tip position of the grasped object in real space reaches a designated position in real space where a speed change of the object is to be performed; a step of controlling a speed at which the object is conveyed by the conveying means based on the speed change command; A transport control method comprising:

12. 12. The transport control method according to claim 11, further comprising outputting a deceleration command as a speed change command for the object when a tip position of the object in real space reaches the designated position, in order to stop the object at a desired position.

13. 12. The transport control method according to claim 11, wherein the steps of detecting and tracking a tip position of the object and determining the tip position in real space from the tip position on the image are performed by recognizing the object on the image, detecting the tip position on the image of the recognized object, and calculating the tip position of the object in real space from the tip position on the detected image.

14. 14. The conveyance control method according to claim 13, wherein the object is a hot steel material that is red-hot and luminous, and the steps of detecting and tracking the tip position and determining the tip position in real space from the tip position on the image include binarizing the image prior to recognizing the object, and detecting the tip position on the image of the object based on a change in brightness of the binarized image.

Images