JP2021067592A - Inspection system - Google Patents

Abstract

To provide an inspection system that can inspect an inspection target object without missing any spot, with a spacial restriction taken in consideration.SOLUTION: According to an embodiment of the present invention, the inspection system for inspecting an inspection target object includes an imaging apparatus and a rotary table, the imaging apparatus including a camera and a driving mechanism, the camera being in the driving mechanism to be movable by the driving mechanism so that the camera can take images of the inspection target object from different points of view and from different lines of vision, and the rotary table being rotatable with the inspection target object on the table.SELECTED DRAWING: Figure 1

Description

The present invention relates to an inspection system.

At the production site, an inspection system including a camera may be used instead of visual inspection by a person to inspect the appearance of the object to be inspected. Patent Document 1 discloses a prior art of an inspection system for inspecting an object to be inspected.

Japanese Unexamined Patent Publication No. 2016-85137

By the way, in order to inspect the object to be inspected without omission in detail, the camera used in the inspection system may have a short focus, and its viewpoint and line of sight may be dynamically changed. However, for a leak-free inspection, it is necessary to increase the movable range of the camera, and there is a problem that a spatial restriction for providing an inspection system occurs. FIG. 10 shows an example of the inspection system 9 according to the prior art. In this figure, there is one drive mechanism and one camera located at the tip thereof, and the movable range thereof is schematically shown. In this conventional technique, the inspection system 9 includes an image pickup device 91 and a fixing device 92, but there is a problem that the image pickup device 91 becomes large and takes up space.

The present invention has been made in view of such circumstances, and an object of the present invention is to provide an inspection system capable of inspecting an inspected object without omission in consideration of spatial restrictions.

According to one aspect of the present invention, it is an inspection system for inspecting an object to be inspected, which includes an image pickup device and a rotary table, the image pickup device includes a camera and a drive mechanism, and the camera includes the camera. The drive mechanism is provided so as to be movable by the drive mechanism so as to photograph the object to be inspected from different viewpoints and lines of sight, and the rotary table is configured to be rotatable on which the object to be inspected is placed. Things are provided.

According to such an inspection system, the inspected object can be inspected without omission while suppressing the influence of spatial constraints. It has the above-mentioned advantageous effects.

It is a top view which shows the appearance of inspection system 1. It is a front view which shows the appearance of inspection system 1. It is a block diagram which shows the hardware structure of inspection system 1. It is a conceptual diagram which shows the line-of-sight and a viewpoint of a camera 21. It is a block diagram which shows the hardware structure of an information processing apparatus 4. It is a functional block diagram which shows the function which the control part 43 in an information processing apparatus 4 has. An example is shown in the case where it is determined that there is no defect in the determination result of the molded body M. An example is shown in the case where it is determined that there is a defect in the determination result of the molded body M. It is an activity diagram of the inspection system 1 which concerns on embodiment. An example of the inspection system 9 according to the prior art is shown.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. The various features shown in the embodiments shown below can be combined with each other. In particular, in the present specification, the "part" may include, for example, a combination of hardware resources implemented by circuits in a broad sense and information processing of software that can be concretely realized by these hardware resources. .. Further, in this embodiment, various information is handled, and these information are represented by high and low signal values as a bit set of binary numbers composed of 0 or 1, and communication / calculation is executed on a circuit in a broad sense. Can be done.

A circuit in a broad sense is a circuit realized by at least appropriately combining a circuit, a circuit, a processor, a memory, and the like. That is, an integrated circuit for a specific application (Application Special Integrated Circuit: ASIC), a programmable logic device (for example, a simple programmable logic device (Simple Programmable Logical Device: SPLD), a composite programmable logic device (Complex Program)) It includes a programmable gate array (Field Programmable Gate Array: FPGA) and the like.

1. 1. Hardware configuration 1-1. Inspection system 1
Section 1 describes the hardware configuration of the inspection system 1 according to the present embodiment. FIG. 1 is a plan view showing the appearance of the inspection system 1. In this figure, there is one drive mechanism 21a and one camera 21 located at the tip thereof, and the movable range thereof is schematically shown. FIG. 2 is a front view showing the appearance of the inspection system 1. FIG. 3 is a block diagram showing a hardware configuration of the inspection system 1. The inspection system 1 for inspecting an object to be inspected includes an image pickup device 2 and a fixing device 3 (rotary table 31). Further, the inspection system 1 further includes an information processing device 4.

In the present embodiment, the object to be inspected targeted by the inspection system 1 is a molded product M having a welded portion, and the welded portion will be described as being inspectable. Such a molded product M has an asymmetrical shape. It should be noted that this is just an example and is not limited to this. Each component will be described in more detail below.

1-2. Imaging device 2
The image pickup device 2 includes a camera 21 and a drive mechanism 21a. Further, the drive mechanism 21a includes a rod 22, a joint 23a, a joint 23b, and a base 24. Details will be described below.

<Camera 21>
The camera 21 is provided in the drive mechanism 21a. The camera 21 is configured to be movable by a drive mechanism 21a so as to photograph the molded body M from different viewpoints and lines of sight. More specifically, the camera 21 is configured to capture a plurality of inspection images IM1 including the molded body M located on the rotary table 31. The inspection image IM1 may be a still image or a moving image. Here, the plurality of inspection images IM1 are images taken from different viewpoints and lines of sight by driving the drive mechanism 21a so as to image the molded body M without omission. A lighting 27 is provided above the camera 21. The illumination 27 is configured to irradiate the molded body M with illumination light so as to ensure the brightness required for each shooting.

The camera 21 is configured to take a picture with an inclination so as to look up at the welded portion slightly upward. With such an inclination, it is possible to improve the detection accuracy for the deviation in the depth direction. Assuming that the inclination angle with respect to the horizontal is θ, for example, θ is 1,1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1. 8,1.9,2,2.1,2.2,2.3,2.4,2.5,2.6,2.7,2.8,2.9,3,3.1 3.2, 3.3, 3.4, 3.5, 3.6, 3.7, 3.8, 3.9, 4, 4.1, 4.2, 4.3, 4.4 4.5, 4.6, 4.7, 4.8, 4.9, 5, 5.1, 5.2, 5.3, 5.4, 5.5, 5.6, 5.7, 5.8, 5.9, 6, 6.1, 6.2, 6.3, 6.4, 6.5, 6.6, 6.7, 6.8, 6.9, 7, 7. 1,7.2,7.3,7.4,7.5,7.6,7.7,7.8,7.9,8,8.1,8.2,8.3,8. 4,8.5,8.6,8.7,8.8,8.9,9,9.1,9.2,9.3,9.4,9.5,9.6,9. It is 7, 9.8, 9.9, 10 degrees, and may be within the range between any two of the numerical values exemplified here.

The camera 21 is provided at the tip of a driveable drive mechanism 21a, and has a variable viewpoint and line of sight. In order to obtain the inspection image IM1 without omission in detail, the lens provided in the camera 21 is preferably a short focus lens. However, since the short focus lens has a shallow depth of field, even a slight misalignment causes the lens to be out of focus. In the present embodiment, the drive mechanism 21a is configured so that the distance from the viewpoint on the camera 21 to the image pickup position on the molded body M can be adjusted. Further, since the image using the single focus lens has a small angle of view, it is necessary to capture the inspection image IM1 by changing the imaging location. Therefore, as the drive mechanism 21a, a mechanism having at least two degrees of freedom in the angle of view direction can be adopted. Preferably, as the drive mechanism 21a, a SCARA robot having four degrees of freedom can be adopted. The main parts constituting the drive mechanism 21a will be described below.

<Rod 22>
The rod 22 is provided on the component 25 and extends vertically downward, and its length is variably configured. As a result, the viewpoint position of the camera 21 can be changed up and down.

<Joint 23a>
The joint 23a is a joint portion and makes the component 25 rotatable with respect to the component 26 (arm). As a result, the line of sight of the camera 21 can be swung left and right.

<Joint 23b>
The joint 23b is a joint portion and makes the component 26 (arm) rotatable with respect to the base 24. As a result, the viewpoint position of the camera 21 can be changed to the left or right.

<Base 24>
The base 24 is fixed to the floor surface or the like on which the inspection system 1 is placed. Therefore, the image pickup apparatus 2 is basically fixed and used at the time of inspection.

1-3. Fixing device 3
The fixing device 3 includes a rotary table 31 and a fixing member 32. Details will be described below.

<Rotary table 31>
The rotary table 31 is configured to be rotatable on which the molded body M is placed. As a result, the orientation of the molded body M imaged by the camera 21 can be changed. The work of placing the molded body M on the rotary table 31 may be performed manually or by a work robot (not shown).

In the image pickup apparatus 2, the line of sight and the viewpoint of the camera 21 can be flexibly changed, but in the inspection system 1 according to the present embodiment, the inspection system 9 according to the prior art (in the inspection system 1 according to the present embodiment) in consideration of the limitation of the installation space. Note that the size of the drive mechanism 21a is smaller than that (see FIG. 10). Therefore, the imaging range of the camera 21 of the inspection system 1 is narrower than the imaging range of the inspection system 9.

FIG. 4 is a conceptual diagram showing the line of sight and the viewpoint of the camera 21. As shown in FIG. 4, the camera 21 is configured to move from the first viewpoint P1 to the second viewpoint P2 so as to photograph the molded body M from different viewpoints and lines of sight. Then, the angle formed by the first line-of-sight vector v_1 from the first viewpoint P1 toward the molded body M and the second line-of-sight vector v_1 from the second viewpoint P2 toward the molded body M is α, and the rotary table 31 can rotate. It should be noted that if the angle is β (not shown), α + β ≧ 360 degrees is satisfied. That is, even if the imaging range of the camera 21 is limited, the rotary table 31 rotates the molded body M, so that the molded body M can be inspected without omission. In particular, considering the miniaturization of the drive mechanism 21a, it is preferable to satisfy α ≦ 180 degrees.

<Fixing member 32>
The fixing member 32 is configured to fix the molded body M placed on the rotary table 31 by pressing it from above. The fixing member 32 can prevent the molded body M from moving or falling even if the rotary table 31 rotates.

1-4. Information processing device 4
FIG. 5 is a block diagram showing a hardware configuration of the information processing device 4. The information processing device 4 has a communication unit 41, a storage unit 42, and a control unit 43 (image processing unit 432, determination unit 433), and these components provide a communication bus 40 inside the information processing device 4. It is electrically connected via. Hereinafter, each component will be further described.

<Communication unit 41>
Although wired communication means such as USB, IEEE1394, Thunderbolt, and wired LAN network communication are preferable, the communication unit 41 can perform wireless LAN network communication, mobile communication such as LTE / 3G, Bluetooth (registered trademark) communication, and the like as necessary. May be included. That is, it is more preferable to carry out as a set of these plurality of communication means. In particular, it is preferable that the camera 21 is configured to be communicable according to a predetermined communication standard.

The communication unit 41 is configured to receive the plurality of inspection images IM1 when the camera 21 captures them. Further, the communication unit 41 is configured to be able to transmit information for controlling each joint angle of the drive mechanism 21a to a desired angle based on inverse kinematics. Further, it is more preferable that the current joint angle can be acquired as information (encoder). With such a configuration, it is possible to control the camera 21 provided at the tip of the drive mechanism 21a so as to be displaced to a desired position and direction in spatial coordinates.

<Memory unit 42>
The storage unit 42 stores various information defined by the above description. This is, for example, as a storage device such as a solid state drive (SSD), or a random access memory (Random Access Memory:) that stores temporarily necessary information (arguments, arrays, etc.) related to program operations. It can be implemented as a memory such as RAM). Moreover, these combinations may be used.

In particular, the storage unit 42 stores the inspection image IM1 imaged by the camera 21 and received by the communication unit 41. The inspection image IM1 is, for example, array information including pixel information of 8 bits for each of RGB. Further, the storage unit 42 stores the operation control program, the acquisition program, the image processing program, and the determination program. In addition to this, the storage unit 42 stores various programs related to the information processing device 4 executed by the control unit 43.

<Control unit 43>
The control unit 43 processes and controls the entire operation related to the information processing device 4. The control unit 43 is, for example, a central processing unit (CPU) (not shown). The control unit 43 realizes various functions related to the information processing device 4 by reading a predetermined program stored in the storage unit 42. Specifically, the operation control function, the acquisition function, the image processing function, and the determination function are applicable. That is, the information processing by the software (stored in the storage unit 42) is specifically realized by the hardware (control unit 43), so that the operation control unit 430, the acquisition unit 431, the image processing unit 432, and the determination unit It can be run as 433.

Although it is described as a single control unit 43 in FIG. 5, it is not limited to this, and it may be implemented so as to have a plurality of control units 43 for each function. Moreover, it may be a combination thereof. The operation control unit 430, the acquisition unit 431, the image processing unit 432, and the determination unit 433 will be described in more detail in Section 2.

2. Functional configuration Section 2 describes the functional configuration of the information processing device 4 (control unit 43) of the inspection system 1. FIG. 6 is a functional block diagram showing a function played by the control unit 43 in the information processing device 4. Hereinafter, each component will be further described.

[Operation control unit 430]
In the operation control unit 430, information processing by software (stored in the storage unit 42) is specifically realized by hardware (control unit 43). The operation control unit 430 controls the drive mechanism 21a and the rotary table 31 connected via the communication unit 41. That is, an electric signal including information instructed by the motion control unit 430 is transmitted to the drive mechanism 21a, and the drive mechanism 21a is driven so that the camera 21 has a desired viewpoint and line of sight. An electric signal including information instructed by the operation control unit 430 is transmitted to the drive system of the rotary table 31, and the rotary table 31 rotates so that the molded body M has a desired orientation.

[Acquisition unit 431]
In the acquisition unit 431, information processing by software (stored in the storage unit 42) is specifically realized by hardware (control unit 43). The acquisition unit 431 is configured to acquire the inspection image IM1 captured by the camera 21 via the communication unit 41.

[Image processing unit 432]
In the image processing unit 432, information processing by software (stored in the storage unit 42) is specifically realized by hardware (control unit 43). The image processing unit 432 executes predetermined image processing on the inspection image IM1 transmitted from the camera 21 and received by the communication unit 41, and generates the processed image IM2. More specifically, a predetermined threshold value is set for the brightness of the inspection image IM1 and converted into a binary image (an example of the processed image IM2).

[Judgment unit 433]
In the determination unit 433, information processing by software (stored in the storage unit 42) is specifically realized by hardware (control unit 43). The determination unit 433 is configured to determine the presence or absence of defects in the molded body M based on the plurality of inspection images IM1 captured by the camera 21. Specifically, the determination unit 433 is configured to determine whether or not there is a defect in the welded portion of the molded body M based on the processed image IM2 created from the inspection image IM1.

In particular, the determination unit 433 determines whether or not the defect is applicable based on at least one of the positions and areas of the locations that are considered to be defects. It should be noted that noise of the camera 21, calculation error in image processing, or a minute defect that does not cause a quality problem may be determined not to be a defect. Further, in view of the line process, the determination unit 433 determines whether or not there is a defect in the molded product M being inspected by the time the next molded product M is conveyed, based on the plurality of inspection images IM1 received by the communication unit 41. It should be configured to do so.

Further, the result of the determination may be displayed on a display device (not shown) or the like so that a human can confirm the result. In particular, since the quality status at the production site is displayed in real time, it is useful for quickly grasping and identifying problems and for quick countermeasures. FIG. 7 shows an example in the case where it is determined that there is no defect in the determination result of the molded product M. FIG. 8 shows an example in the case where it is determined that there is a defect in the determination result of the molded body M.

3. 3. Inspection method Section 3 describes the inspection method using the inspection system 1 described so far. FIG. 9 is an activity diagram of the inspection system 1 according to the embodiment. Hereinafter, description will be given with reference to this figure.

[from here]
(Activity A01)
The molded body M is placed on the rotary table 31, and one side of the molded body M can be imaged. In this state, the motion control unit 430 drives the drive mechanism 21a to control the camera 21 so as to have a predetermined viewpoint and line of sight.

(Activity A02)
The camera 21 images one side of the molded body M with the desired viewpoint and line of sight determined in activity A01. Activities A01 and A02 are performed from a plurality of viewpoints and lines of sight.

(Activity A03)
Subsequently, the rotary table 31 is rotated 180 degrees so that the other side of the molded body M can be imaged.

(Activity A04)
In this state, the motion control unit 430 drives the drive mechanism 21a to control the camera 21 so as to have a predetermined viewpoint and line of sight.

(Activity A05)
The camera 21 images the other side of the molded body M with the desired viewpoint and line of sight determined in activity A04. Activities A04 and A05 are performed from multiple viewpoints and lines of sight.

(Activity A06)
The acquisition unit 431 of the information processing device 4 acquires the inspection image IM1 from the camera 21 via the communication unit 41.

(Activity A07)
The image processing unit 432 of the information processing device 4 performs appropriate image processing on the inspection image IM1 acquired by the acquisition unit 431 to generate the processed image IM2.

(Activity A08)
The determination unit 433 in the information processing apparatus 4 determines the presence or absence of defects in the molded body M based on the processed image IM2.

(Activity A09)
Finally, the rotary table 31 is rotated 180 degrees again to return to the initial state.
[to this point]

4. Modification Example Section 4 describes a modification of the inspection system 1 according to the present embodiment. That is, the inspection system 1 may be provided in the following aspects.

(1) Instead of the drive mechanism 21a, the position coordinates of the camera 21 or the like may be changed by using the XYZ stage.
(2) The fixing device 3 may be provided with a mechanism for translating the molded body M (for example, an XYZ stage or the like).
(3) There may be a plurality of cameras 21.
(4) In addition to the camera 21, different types of sensors may be added.
(5) The rotary table 3 is not limited to one that is rotated 180 degrees once, and may be finely and continuously rotated. Alternatively, it may be rotated by a specified discrete value, such as 45 degrees, 60 degrees, 90 degrees, or 120 degrees.

5. Conclusion As described above, according to the present embodiment, it is possible to realize an inspection system capable of appropriately determining the presence or absence of defects in the subject to be inspected having a difficult-to-see region that cannot be viewed from the front.

It may be provided in each of the following aspects.
In the inspection system, the drive mechanism is configured to be able to adjust the distance from the viewpoint of the camera to the imaging location of the object to be inspected.
In the inspection system, the camera is configured to move from a first viewpoint to a second viewpoint so as to capture an object to be inspected from different viewpoints and lines of sight, and from the first viewpoint to the object to be inspected. Let α be the angle formed by the first line-of-sight vector v_1 heading toward the object and the second line-of-sight vector v_1 heading toward the object to be inspected from the second viewpoint, and β be the angle at which the rotary table can rotate, α + β ≧ 360 degrees. Those that meet.
In the inspection system, one that satisfies α ≦ 180 degrees.
The inspection system further includes an information processing device, the information processing device includes a determination unit, and the determination unit is based on a plurality of inspection images captured by the camera and has a defect in the object to be inspected. What is configured to determine.
In the inspection system, the object to be inspected is a molded product having a welded portion, and the welded portion can be inspected.
Of course, this is not the case.

Finally, various embodiments of the present invention have been described, but these are presented as examples and are not intended to limit the scope of the invention. The novel embodiment can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the gist of the invention. The embodiment and its modifications are included in the scope and gist of the invention, and are included in the scope of the invention described in the claims and the equivalent scope thereof.

1: Inspection system 2: Imaging device 21: Camera 21a: Drive mechanism 22: Rod 23a: Joint 23b: Joint 24: Base 25: Parts 26: Parts 27: Lighting 3: Fixing device 31: Rotating table 32: Fixing member 4: Information processing device 40: Communication bus 41: Communication unit 42: Storage unit 43: Control unit 430: Operation control unit 431: Acquisition unit 432: Image processing unit 433: Judgment unit 9: Inspection system 91: Imaging device 92: Fixing device IM1 : Inspection image IM2: Processed image M: Molded body P1: First viewpoint P2: Second viewpoint v_1: First line-of-sight vector v_2: Second line-of-sight vector

Claims (6)

It is an inspection system that inspects the object to be inspected.
Equipped with an image pickup device and a rotary table
The image pickup device includes a camera and a drive mechanism.
The camera
Provided in the drive mechanism
It is configured to be movable by the drive mechanism so as to photograph the object to be inspected from different viewpoints and lines of sight.
The rotary table is configured to be rotatable on which the object to be inspected is placed. In the inspection system according to claim 1,
The drive mechanism is configured so that the distance from the viewpoint of the camera to the imaging location of the object to be inspected can be adjusted. In the inspection system according to claim 1,
The camera is configured to move from a first viewpoint to a second viewpoint so as to capture an object to be inspected from different viewpoints and lines of sight.
The angle formed by the first line-of-sight vector v_1 from the first viewpoint toward the object to be inspected and the second line-of-sight vector v_1 from the second viewpoint toward the object to be inspected is α, and the rotary table can be rotated. If the angle is β,
Those that satisfy α + β ≧ 360 degrees. In the inspection system according to claim 2,
Those that satisfy α ≤ 180 degrees. In the inspection system according to any one of claims 1 to 4.
Equipped with more information processing equipment
The information processing device includes a determination unit.
The determination unit is configured to determine the presence or absence of defects in the object to be inspected based on a plurality of inspection images captured by the camera. In the inspection system according to any one of claims 1 to 5.
The object to be inspected is a molded product having a welded portion, and the welded portion can be inspected.

Images