The present specification discloses an image processing device, a work robot, a board inspection device, and a specimen inspection device.
Conventionally, as an image processing device, a device has been proposed which is configured to acquire image data of a two-dimensional image (a planar image) of an object and detect the position and orientation of the object in three-dimensional space based on the image data (see, for example, Patent Document 1). In this device, a template image of each surface of the object is prepared, the visible surface is detected from the image of the object within the acquired image data, and the template image corresponding to each visible surface is read in and the converted image data in which the line-of-sight direction is changed in accordance with the line-of-sight direction of the image data for each template image is generated. The image processing device then calculates the degree of matching between the image data and the converted image data, and obtains the position and the orientation of the object based on the surface having the highest reliability among surfaces whose degree of matching exceeds a threshold value and have been thus deemed effective.
Patent Document 1: Japanese Patent Publication No. 2012-185752
In the image processing device described above, a conversion process using a conversion matrix is performed on all points on the visible surface of the captured image data to generate converted image data. As a result, the processing load of the image processing device may increase, causing the image processing device to take time to recognize the position and the orientation.
It is a principal object of the present disclosure to accurately recognize the position and orientation of an object while moderating the processing load.
The present disclosure has taken following means to achieve the main object described above.
The image processing device of the present disclosure has a storage section configured to store a three-dimensional shape model in which feature amounts and three-dimensional positional information for multiple feature points of a target object are associated; an extraction process section configured to extract the feature amounts and two-dimensional positional information of the feature points from a two-dimensional image of the target object captured with a camera; and a recognition process section configured to identify three-dimensional positional information of the feature points for the two-dimensional image and recognize the position and orientation of the target object by matching the feature points of the two-dimensional image with the feature points of the three-dimensional shape model using the feature amounts.
The image processing device of the present disclosure recognizes the position and orientation of the target object by extracting the feature amounts and the two-dimensional positional information of the feature points from the two-dimensional image of the target object captured with the camera and matching the feature points of the two-dimensional image with the feature points of the three-dimensional shape model using the feature amounts. As a result, when recognizing the position and the orientation of the target object, it is sufficient to match the feature points extracted from the two-dimensional image of the target object with the feature points of the three-dimensional shape model, making it possible to reduce the processing load since it is not necessary to perform the process for all the points in the image. Further, matching can be appropriately performed using the feature amount of each feature point. Accordingly, it is possible to accurately recognize the position and orientation of the target object while suppressing the processing load.
Next, embodiments of the present disclosure will be described with reference to the drawings.
Work robot 20 includes vertical multi-jointed robot arm 22 having a chuck as a work tool at the distal end, camera 24 attached to the distal end of robot arm 22, and image processing device 30 for processing an image captured by camera 24. Work robot 20 performs an operation of picking up workpiece W from conveyor belt 12a with the chuck by operation of robot arm 22, placing workpiece W on tray T, assembling workpiece W at a predetermined position, and the like. Camera 24 captures a two-dimensional image in order to recognize the position and orientation of workpiece W and outputs the image to image processing device 30. Image processing device 30 is configured by an HDD or the like, includes storage section 32 for storing a program necessary for image processing, three-dimensional shape model M, or the like, and is connected to input devices 38, such as a keyboard and a mouse, and output device 39, such as a display.
Next, various types of processes of robot system 10 for recognizing the position and orientation of workpiece W will be described. First, a preparation process for recognition will be described.
In the image acquisition process in
If it is determined in S240 that the amount of positional deviation is equal to or greater than the predetermined amount, image processing device 30 outputs a warning regarding the positional deviation of workpiece W to output device 39 (S250) and waits for the operator to reposition workpiece W to the center of the imaging area (S260). When the operator repositions workpiece W, he/she inputs a message to that effect using input device 38. If it is determined that workpiece W is repositioned, image processing device 30 returns to S220. On the other hand, when it is determined in S240 that the amount of positional deviation is less than the predetermined amount, image processing device 30 subsequently moves camera 24 horizontally above multiple viewpoints Ei by controlling work robot 20 with control device 18 to capture multiple two-dimensional images Gi (S270) and terminates the image acquisition process. As shown in
When the two-dimensional images Gi are acquired in this manner in S100, image process device 30 extracts feature points P (feature data 2Di (x, y; f)), which are key points, from each two-dimensional image Gi in S110. Image processing device 30 obtains, for example, brightness distribution of two directions orthogonal to each other from brightness values of each pixel in each two-dimensional image Gi, and extracts, as feature points P, points at which the differential is equal to or greater than a predetermined amount. As a result, feature points P easily appear at a vertex of workpiece W, boundary points between different materials of workpiece W, boundary points between different surface properties of workpiece W, or the like, so that light reflections, noise, or the like can be easily suppressed. In
In the model creation process of
Next, image processing device 30 determines whether the number of appearances of the feature points P is equal to or more than a predetermined number (S320), sets the feature points P as feature points Pm targeted for registration in three-dimensional shape model M (S330) if it is determined that the number is equal to or greater than the predetermined number, and excludes the feature points P from being targeted for registration in three-dimensional shape model M (S340) if it is determined that the number is not equal to or greater than the predetermined number. The predetermined number is appropriately set to a value that excludes feature points P that appear only in two-dimensional images G4, G5 in
Next, a process for recognizing the position and orientation of workpiece W, which is a target object, when robot system 10 performs an operation on workpiece W will be described.
In the matching process of
Next, image processing device 30 projects an image of three-dimensional shape model M on two-dimensional image Ga based on the set approximate positions Pr (S520, see
Here, correspondence between constituent elements of the first embodiment and constituent elements of the present disclosure will be described. Storage section 32 of the first embodiment corresponds to a storage section, image processing device 30 that executes S410 of the recognition process of
In work robot 20 of the first embodiment described above, image processing device 30 recognizes the position and orientation of workpiece W by matching the feature points P of two-dimensional image Ga of workpiece W captured by camera 24 with the feature points Pm of three-dimensional shape model M. Therefore, since image processing device 30 does not have to perform the process for all points in two-dimensional image Ga and can properly perform matching based on the feature descriptor f of the feature point P, the position and orientation of workpiece W can be accurately recognized while suppressing the processing load. Further, work robot 20 can improve work accuracy by properly picking up workpiece W. Further, work robot 20 does not need to have a relatively large camera or a relatively expensive camera for capturing three-dimensional images.
In addition, even in a case where the three-dimensional shape data of workpiece W cannot be acquired, image processing device 30 can generate three-dimensional shape model M from multiple two-dimensional images Gi of workpiece W. In addition, since image processing device 30 sends out a warning when workpiece W is offset from the center position, it is possible to appropriately obtain the height z of the feature point P from the two-dimensional image Gi in which parallaxes appropriately appear. In addition, since image processing device 30 creates three-dimensional shape model M by excluding feature points P having a small number of appearances, it is possible to further improve the recognition accuracy of workpiece W while reducing the processing load of matching. In addition, since image processing device 30 adjusts the approximate positions Pr so that the degree of overlap between the projected image of three-dimensional shape model M and two-dimensional image Ga increases, the error in matching can be appropriately corrected. In addition, image processing device 30 can improve the extraction accuracy of the feature descriptor f of the feature point P by machine learning such as DNN.
Next, a second embodiment will be described.
Printing device 110 includes printing control device 111, printing section 112, and camera 113. Printing section 112 presses the solder into the pattern holes of the screen mask using a squeegee to print the solder on board B. Printing control device 111 controls printing section 112 so as to print solder at a predetermined printing position based on the two-dimensional image captured with camera 113. Print inspection device 115 includes inspection control device 116, image processing device 117, and camera 119. Image processing device 117 is configured to perform various types of image processing on a two-dimensional image of board B captured with camera 119 and includes storage section 118 for storing three-dimensional shape model Mb or the like of the solder printed on board B. Inspection control device 116 inspects the printing state based on the processing result of image processing device 117 performed on the two-dimensional image captured with camera 119 and controls the entire print inspection device 115.
Mounting device 120 includes mounting control device 121, mounting section 122, and camera 123. Mounting section 122 includes a head including a suction nozzle, picks up a component supplied by a supply section (not shown) with the suction nozzle, moves the head above board B, and mounts the component on board B. Mounting control device 121 controls mounting section 122 so that the component is mounted at a predetermined mounting position based on the two-dimensional image captured with camera 123. Mounting inspection device 125 includes inspection control device 126, image processing device 127, and camera 129. Image processing device 127 is configured to perform various types of image processing on a two-dimensional image of board B captured with camera 129, and includes storage section 128 for storing three-dimensional shape model Mc or the like of the component mounted on board B. Inspection control device 116 inspects the mounting state of the component or controls the entire mounting inspection device 125 based on the processing result of image processing device 127 performed on the two-dimensional image captured with camera 129.
In the second embodiment, for example, the same processes as the preparation process and the recognition process described above are performed by image processing device 117 of print inspection device 115 (board inspection device) targeting printed matter (resulting object) such as solder printed on board B as a target object. In the preparation process, image processing device 117 captures an image of multiple two-dimensional images Gi by targeting printed matter as a reference and extracts feature points P such as vertices of the printed matter from each two-dimensional image Gi. Image processing device 117 then generates feature data 3Di (x, y, z; f) of each extracted feature point P, and creates three-dimensional shape model Mb, and stores three-dimensional shape model Mb in storage section 118. In the recognition process, image processing device 117 captures two-dimensional image Ga of board B on which the printed matter is formed, extracts feature points P, matches feature points P with feature points Pm of three-dimensional shape model Mb using feature descriptors f, and recognizes each vertex position and orientation of the printed matter. Based on the recognition result, inspection control device 116 can inspect the printing state such as whether the height of the solder printed on board B is appropriate and whether the amount (volume) of solder is appropriate. That is, print inspection device 115 can inspect the three-dimensional printing state of board B from the two-dimensional image of the printed matter.
In the second embodiment, the target object is not limited to the printed matter and may be any of the following. For example, image processing device 127 of mounting inspection device 125 (board inspection device) executes a preparation process and stores three-dimensional shape model Mc in storage section 128 with a component (resulting object) mounted on board B as a target object. In addition, inspection control device 126 may perform an inspection of the mounting state such as determining whether the height of the component mounted on board B is normal or whether the inclination degree is within an allowable range based on the result of the recognition process of image processing device 127 based on two-dimensional image Ga and three-dimensional shape model Mc of the component. Inspection control device 126 can also inspect the presence or absence of a defect in the component based on whether feature points P appear at positions different from feature points Pm of three-dimensional shape model Mc. Alternatively, mounting device 120 may include an image processing device and may execute a preparation process or a recognition process with a supplied component as a target object. Examples of this type of mounting device 120 include a bulk feeder that accommodates multiple components in a scattered state and supplies the components while aligning the components, and a tray feeder that accommodates and supplies multiple components on a flat tray. By appropriately recognizing the position and orientation of components supplied from such a feeder, components can be appropriately picked up (adsorbed).
Next, a third embodiment will be described.
In the third embodiment, for example, the same process as the preparation process and the recognition process described above is executed by image processing device 230 using a specific inspection target in the specimen as a target object. Examples of the object (i.e., a specific test object) include, but are not limited to, bacteria, viruses, and proteins. Image processing device 230 captures multiple two-dimensional images Gi of a reference object and extracts feature points P such as the vertices of the object from each two-dimensional image Gi. Image processing device 230 then generates feature data 3Di (x, y, z; f) of each extracted feature point P, and creates three-dimensional shape model Md, and stores three-dimensional shape model Mb in storage section 232. Further, in the recognition process, image processing device 230 captures two-dimensional image Ga of the specimen, extracts feature points P, matches feature points P with feature points Pm of three-dimensional shape model Md using feature descriptors f, and recognizes each vertex position or orientation of the specimen. Based on the recognition result, inspection control device 202 can detect or inspect a target object in the specimen. That is, specimen inspection device 200 can accurately inspect a target object having a three-dimensional shape in the specimen from the two-dimensional image of the specimen. In addition, in such an inspection, although it is difficult to obtain three-dimensional CAD data or the like of the target object, it is possible to appropriately generate three-dimensional shape model Md from multiple two-dimensional images Gi.
It is to be understood that the present disclosure is not limited to the embodiments described above in any way, and may be executed in various forms as long as the embodiments belong to the technical scope of the present disclosure.
For example, although three-dimensional shape model M is generated from multiple two-dimensional images Gi in the above embodiment, the present disclosure is not limited to this, and three-dimensional shape model M may be generated from drawing data such as CAD data of the target object. Further, image processing device 30 is not limited to a device for creating three-dimensional shape model M, and three-dimensional shape model M created by another device may be stored in storage section 32 or the like.
In the above embodiment, although a warning is sent out when workpiece W is offset from the center position when capturing two-dimensional images Gi, the present disclosure is not limited to this, and such a warning may be omitted. However, it is preferable to send out a notification for the purpose of acquiring two-dimensional images Gi in which parallaxes appropriately appear.
In the above embodiment, three-dimensional shape model M is created by excluding feature points P having a small number of appearances, but the present disclosure is not limited to this, and three-dimensional shape model M including the extracted feature points P may be created regardless of the number of appearances.
In the above embodiment, approximate positions Pr are adjusted so that the degree of overlap between the projected image on which three-dimensional shape model M is projected and two-dimensional image Ga is increased to identify the three-dimensional position information of feature points P, but the present disclosure is not limited to this. Without performing such superimposition, the positions of feature points P may be identified by matching.
In the above embodiment, the feature amounts are extracted using machine learning such as DNN, but the present disclosure is not limited to this, and any method may be used as long as the feature amounts of the feature points P such as the SURF feature amounts or the SIFT feature amounts are extracted.
In the first embodiment described above, vertical multi-jointed work robot 20 is used as an example, but the present disclosure is not limited to this, and may be a horizontal multi-jointed robot, a parallel-link robot, or the like. Further, application of the present disclosure is not limited to a work robot, a board inspection device, and a specimen inspection device, and may be applied to other devices such as a machine tool or the like. The image processing device is not limited to those provided in the devices of the present disclosure, and may be configured as an independent device. Although the present disclosure is applied to the detection of a protein or the like in the third embodiment described above, the present disclosure is not limited to this, and may be applied to image processing of a microscopic object on the micrometer or nanometer scale. Further, the present disclosure may be applied to image processing when a predetermined operation using a micromanipulator or the like is performed on such a microscopic object.
The image processing device of the present disclosure may be configured as follows. For example, the image processing device of the present disclosure may be an image processing device in which the extraction process section is provided with a creation process device configured to acquire multiple two-dimensional images of the target object captured with the camera at multiple viewpoints in a state in which the target object to be a reference is disposed at a predetermined position, extract feature amounts and two-dimensional positional information of the feature points from multiple two-dimensional images, create three-dimensional positional information by obtaining height information of the feature points from parallax between the two-dimensional images, create the three-dimensional shape model in which the feature amounts and the three-dimensional positional information are associated with the feature points, and store the three-dimensional shape model in the storage section. As a result, it is possible to create a three-dimensional shape model even in a case in which the three-dimensional shape data of the target object cannot be acquired.
The image processing device of the present disclosure may be an image processing device in which the extraction processing device acquires images, which are to become the two-dimensional images, captured by subsequently moving the camera from multiple viewpoints with respect to the predetermined position while the target object to be a reference is disposed at the predetermined position; and the extraction process device comprises a notification section configured to send out a warning when the amount of positional deviation of the target object from the predetermined position is equal to or greater than a predetermined allowable amount. As a result, since the height information of the feature points can be obtained from the two-dimensional image in which the parallaxes appropriately appear, it is possible to accurately generate the three-dimensional model.
The image processing device of the present disclosure may be an image processing device in which the creation process section counts, for each of the feature points extracted from the multiple two-dimensional images, the number of times the feature points appear in the multiple two-dimensional images and creates the three-dimensional shape model using the feature points whose counted number of appearances are equal to or greater than a predetermined number. As a result, since a three-dimensional shape model in which the feature points having small number of appearances and low reliability are eliminated can be created, it is possible to further improve the recognition accuracy of the target object while reducing the burden of the matching process.
The image processing device of the present disclosure may be an image processing device in which the recognition process section identifies the three-dimensional positional information of the feature points by setting approximate positions of the feature points by the matching, projecting an image of the three-dimensional shape model on the two-dimensional image based on the set approximate positions, and adjusting the approximate positions so as to increase the degree of overlap between the projected image and the two-dimensional image. As a result, it is possible to appropriately correct the error of the matching so that the position and orientation of the target object can be recognized with higher accuracy.
The image processing device of the present disclosure may be an image processing device in which the extraction process section extracts the feature amounts by predetermined machine learning. As a result, it is possible to appropriately perform matching while improving the extraction accuracy of the feature amounts of the feature points.
The work robot of the present disclosure includes any of the image processing devices described above and a camera configured to capture the two-dimensional image of the workpiece as the target object; wherein the work robot picks up the workpiece based on the workpiece recognition result on the workpiece recognized by the image processing device from the two-dimensional image captured with the camera and performs a predetermined operation. Since the work robot of the present disclosure picks up a workpiece based on the recognition result of the workpiece recognized by any of the image processing devices described above and performs a predetermined operation, the work accuracy is improved by appropriately picking up the workpiece.
The board inspection device of the present disclosure includes any of the image processing devices described above and a camera configured to capture, as the target object, a two-dimensional image of a resulting object provided on a board by a predetermined operation on the board; wherein the board inspection device performs inspection of the board based on the recognition result of the resulting object recognized by the image processing device from the two-dimensional image captured with the camera. Since the board inspection device of the present disclosure inspects the board based on the recognition result of the resulting object recognized by any of the image processing devices described above, the board inspection is accurately performed using the two-dimensional image of the resulting object.
The specimen inspection device of the present disclosure includes any of the image processing device described above, a microscope device configured to enlarge an image of a specimen which is the target object, a camera configured to capture a two-dimensional image of the specimen enlarged by the microscope device; and the specimen inspection device inspects the specimen based on the recognition result of the specimen recognized by the image processing device from the two-dimensional image captured with the camera. Since the specimen inspection device of the present disclosure performs the inspection of the specimen based on the recognition result of the specimen recognized by any of the image processing devices described above, the inspection of the specimen is accurately performed using the two-dimensional image of the specimen enlarged by the microscope device.
The present disclosure can be applied to, for example, the manufacturing industry for image processing devices, work robots, board inspection device, and specimen inspection devices.
10 Robot system, 12 Supply device, 12a Conveyor belt, 14 Conveyance device, 18 Control device, 20 Work robot, 22 Robot arm, 24,113,119,123,129,213 Camera, 30,117,127,230 Image processing device, 32,118,128,232 Storage device, 38,238 Input device, 39,239 Output device, 100 Board work line, 110 Printing device, 111 Printing control device, 112 Printing device, 115 Print inspection device, 116,126,202 Inspection control device, 120 Mounting device, 121 Mounting control device, 122 Mounting section, 125 Mounting inspection device, 200 Specimen inspection device, 210 Microscope device, 212 Microscope section, 212a Stage, 212b Lens, M, Mb, Mc, Md Three-dimensional shape model, B Board, T Tray, W Workpiece
Filing Document | Filing Date | Country | Kind |
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PCT/JP2019/000412 | 1/9/2019 | WO | 00 |