Three-dimensional sensor, robot system, and three-dimensional measurement method

Abstract

Provided is a three-dimensional sensor capable of measuring, at high accuracy and in a short period of time, the three-dimensional shape of a work object. This three-dimensional sensor comprises: a projector that projects a plurality of types of projection patterns onto a work object; and a camera that captures images of the work object onto which the projection patterns are projected. The projection patterns include: a first projection pattern for three-dimensionally measuring the work object according to a first measurement algorithm; and a second projection pattern for three-dimensionally measuring the work object according to a second measurement algorithm.

Description

3D Sensor, Robot System, and 3D Measurement Method

[0001] The present disclosure relates to a 3D sensor, a robot system, and a 3D measurement method.

[0002] Conventionally, a robot system configured to measure a work piece with a 3D sensor (vision sensor) and perform a predetermined operation on the measured work piece by a robot has been put into practical use. As this vision sensor, a projector projects a projection pattern onto the work piece, and the work piece onto which the projection pattern is projected is imaged by a camera (for example, a set of stereo cameras), and the 3D shape of the work piece is measured from the captured image. Here, as the pattern projected from the projector onto the work piece, for example, a random dot pattern (random pattern) and a stripe pattern (stripe pattern) are known.

[0003] Conventionally, various 3D sensors have been proposed that project a projection pattern onto a work piece and image the work piece onto which the projection pattern is projected to measure the 3D shape of the work piece.

[0004] Japanese Patent Application Laid-Open No. 2015-222220 International Publication No. 2021-065608

[0005] As described above, as the 3D sensor used in the conventional robot system, those that project a random dot pattern onto the work piece to measure the 3D shape, and those that project a stripe pattern onto the work piece to measure the 3D shape are known.

[0006] A 3D sensor that measures the 3D shape of a workpiece by projecting a random dot pattern works by, for example, projecting one type of random dot pattern onto the workpiece and then imaging the projected random dot pattern with a set of stereo cameras. Therefore, although the accuracy is not very high, it is possible to measure the 3D shape of the workpiece at high speed. In other words, a 3D sensor using a random dot pattern can perform measurement even if only one type of random dot pattern is projected (once), thus reducing the number of projections and enabling high-speed 3D measurement, but it has the challenge of low 3D measurement resolution.

[0007] On the other hand, a 3D sensor that measures the 3D shape of a workpiece by projecting a striped pattern requires the projection of multiple types of striped patterns with varying positions (phases) and widths of the stripes. While this makes it difficult to measure the 3D shape of a workpiece in a short time, it allows for high-precision measurement of the 3D shape of the workpiece. In other words, a 3D sensor using a striped pattern offers high resolution for 3D measurement and enables high-precision 3D measurement based on a high-definition 3D image. However, it has the drawback of requiring longer measurement times because it needs to project multiple types of striped patterns.

[0008] Thus, methods such as projecting a random dot pattern onto a workpiece to measure its three-dimensional shape, and projecting a striped pattern onto a workpiece to measure its three-dimensional shape, each have their own advantages and disadvantages, and none have been entirely satisfactory. Therefore, there is a demand for a three-dimensional sensor, robot system, and three-dimensional measurement method that can measure the three-dimensional shape of a workpiece with high accuracy in a short amount of time.

[0009] According to one embodiment of the present disclosure, a three-dimensional sensor is provided comprising a projector that projects multiple types of project patterns onto a work object, and a camera that images the work object onto which the project patterns are projected. The project patterns include a first project pattern that performs three-dimensional measurement of the work object according to a first measurement algorithm, and a second project pattern that performs three-dimensional measurement of the work object according to a second measurement algorithm.

[0010] Figure 1 is a schematic diagram showing an example of a robot system equipped with a three-dimensional sensor according to this embodiment. Figure 2 is a block diagram showing an example of a robot system equipped with one embodiment of the three-dimensional sensor according to this embodiment. Figure 3 is a block diagram illustrating one embodiment of the three-dimensional sensor according to this embodiment. Figure 4 is a diagram illustrating an example of a project pattern used with the three-dimensional sensor shown in Figure 3. Figure 5 is a block diagram showing an example of a robot system equipped with another embodiment of the three-dimensional sensor according to this embodiment. Figure 6 is a flowchart illustrating an example of processing in one embodiment of the three-dimensional measurement method according to this embodiment.

[0011] Hereinafter, embodiments of the three-dimensional sensor, robot system, and three-dimensional measurement method according to this embodiment will be described in detail with reference to the accompanying drawings. In each drawing, identical or similar components are denoted by the same or similar reference numerals. Furthermore, the embodiments described below do not limit the technical scope of the invention and the meaning of terms as described in the claims.

[0012] Figure 1 is a schematic diagram showing an example of a robot system equipped with a three-dimensional sensor according to this embodiment. In Figure 1, reference numeral 1 denotes the robot, 2 denotes the robot control device, 3 denotes the vision sensor (three-dimensional sensor), 100 denotes the robot system, and W denotes the work object (workpiece). Here, Figure 1 shows the image captured by the vision sensor (camera) 3 when a predetermined projection pattern is projected onto a workpiece W placed on the installation floor F. An end effector (work tool) 12 is provided at the tip of the arm portion 11 of the robot 1.

[0013] As shown in Figure 1, the robot system 100 comprises a robot 1, a robot control device 2, and a three-dimensional sensor 3. The robot control device 2 controls the robot 1 to perform a predetermined operation on the workpiece W using a work tool 12, based on a pre-installed machining (operation) program and image information from the three-dimensional sensor 3. In Figure 1, the three-dimensional sensor 3 is attached to the wrist of the robot 1, but the attachment location of the three-dimensional sensor 3 is not limited to the wrist of the robot 1.

[0014] As shown in Figure 1, for example, when a predetermined projection pattern is projected onto a workpiece W, the first portion Wa and the second portion Wb of the workpiece W placed on the installation floor F are recognized in the image 300 captured by the camera of the 3D sensor 3 as the first image portion Wa' and the second image portion Wb' of the workpiece W' placed on the installation floor F'.

[0015] Incidentally, various proposals have been made to accurately measure the three-dimensional shape of a workpiece W, even when the shape of the workpiece W is complex or when multiple workpieces are stacked on top of each other. For example, a vision sensor (3D sensor) has been proposed that projects a predetermined projection pattern onto the workpiece W from a projector, and then uses a vision sensor to image the workpiece W onto which the projection pattern has been projected to measure the three-dimensional shape of the workpiece W.

[0016] Specifically, known patterns that can be projected from a projector onto a workpiece W include, for example, random patterns (random dot patterns) and stripe patterns (striped patterns). Here, a 3D sensor that projects a random dot pattern to measure the 3D shape of a workpiece can perform high-speed 3D measurement because only one type of random dot pattern needs to be projected, but it has the problem of low 3D measurement resolution. On the other hand, a 3D sensor that projects a striped pattern to measure the 3D shape of a workpiece has high 3D measurement resolution and can perform high-precision 3D measurement based on a high-definition 3D image, but it has the problem of requiring a long measurement time because it is necessary to project multiple types of striped patterns.

[0017] In this embodiment, the robot system 100 equipped with the three-dimensional sensor 3 enables the creation of a three-dimensional shape of the work object W with high precision in a short time. In the following description, random dot patterns and stripe patterns are described as examples of project patterns, but it is also possible to use laser cutting (optical cutting) or various other project patterns.

[0018] Figure 2 is a block diagram showing an example of a robot system equipped with one embodiment of the three-dimensional sensor according to this embodiment, and Figure 3 is a block diagram for explaining one embodiment of the three-dimensional sensor according to this embodiment. As shown in Figures 1 and 2, the robot system 100 equipped with one embodiment of the three-dimensional sensor 3 according to this embodiment comprises a robot 1, a robot control device 2, and a three-dimensional sensor (vision sensor) 3. The robot control device 2 comprises a three-dimensional image acquisition unit 21 that acquires three-dimensional images (three-dimensional measurement images) output from the three-dimensional sensor 3, a robot control unit 22 that controls the robot 1 (work tool 12) based on an operation program and image information from the three-dimensional image acquisition unit 21, and a storage device 23 that stores the operation program and various data.

[0019] As shown in Figure 3, the 3D sensor 3 includes a 3D image processing unit 30 including a storage unit 33 and a processing unit 34, a projector 31, and a pair of cameras (stereo cameras) 32a and 32b provided on both sides of the projector 31. The storage unit 33 stores, for example, multiple project patterns such as a random dot pattern (first project pattern) and a stripe pattern (second project pattern), as well as an image processing program for processing images captured from the stereo cameras 32a and 32b.

[0020] The processing unit 34 includes an arithmetic processing unit and processes measurement algorithms using random dot patterns (first measurement algorithm) and stripe patterns (second measurement algorithm), as well as processing images captured from stereo cameras 32a and 32b to perform three-dimensional measurement of the workpiece W. The processing unit 34 also performs tasks such as selecting a project pattern to be projected from the projector 31 onto the workpiece W based on an image processing program, and selecting a measurement algorithm corresponding to the selected project pattern.

[0021] Here, the 3D sensor 3 may be attached to the wrist of the robot 1, for example, as shown in Figure 1, but it is not limited to the wrist of the robot 1 and can be attached to the most optimal location in each robot system.

[0022] Figure 4 illustrates an example of a projection pattern used in the 3D sensor shown in Figure 3. Figure 4(a) shows an example of a random dot pattern 311, and Figure 4(b) shows an example of a stripe pattern 312. 3D measurement of a workpiece W using the random dot pattern 311 is performed, for example, by projecting one type of random dot pattern 311 onto the workpiece W from a projector 31. Furthermore, the workpiece W onto which the random dot pattern 311 is projected is imaged by a pair of stereo cameras 32a and 32b located on both sides of the projector 31. The images captured by the stereo cameras 32a and 32b (stereo images) are then processed by a processing unit 34 according to a measurement algorithm (first measurement algorithm) and an image processing program corresponding to the random dot pattern 311 to generate a 3D image (a 3D measurement image based on the random dot pattern 311).

[0023] Next, for 3D measurement of the workpiece W using the striped pattern 312, for example, the striped pattern 312 is projected onto the workpiece W from the projector 31 multiple times (multiple types) while shifting its position (phase) or changing the width of the stripes, and each time the workpiece W onto which the striped pattern 312 is projected is imaged by the stereo cameras 32a and 32b. Then, the processing unit 34 processes the images captured by the stereo cameras 32a and 32b according to a measurement algorithm (second measurement algorithm) and image processing program corresponding to the striped pattern 312 to generate a 3D image (3D measurement image based on the striped pattern 312).

[0024] The 3D image generated by the 3D sensor 3, that is, the 3D measurement image based on either or both of the 3D image generated using the random dot pattern 311 and the 3D image generated using the stripe pattern 312, is input to the 3D image acquisition unit 21 of the robot control device 2. Thus, according to one embodiment of the 3D sensor according to this embodiment, for example, first, a 3D image of the workpiece W is generated using the random dot pattern 311, which has low resolution but enables high-speed measurement, and then a 3D image of the workpiece W is generated using the stripe pattern 312, which requires a longer measurement time but enables high-precision measurement. This makes it possible to determine the 3D shape of the workpiece W with high precision in a short amount of time.

[0025] Figure 5 is a block diagram showing an example of a robot system equipped with another embodiment of the three-dimensional sensor according to this embodiment. In one embodiment of the three-dimensional sensor according to this embodiment, described with reference to Figures 1 to 4, a three-dimensional image processing unit 30 is provided inside the three-dimensional sensor 3. In contrast, in another embodiment of the three-dimensional sensor according to this embodiment shown in Figure 5, the three-dimensional image processing unit 30 is omitted from the three-dimensional sensor 3, and instead, the robot control device 2 is provided with a three-dimensional image processing unit 20 that corresponds to the three-dimensional image processing unit 30.

[0026] In other words, in a robot system equipped with another embodiment of the 3D sensor according to this embodiment, the storage of multiple project patterns such as the random dot pattern 311 and the stripe pattern 312, as well as the storage of image processing programs for processing images captured from stereo cameras 32a and 32b, are performed not by the 3D sensor 3, but by the robot control device (control device) 2. Furthermore, in a robot system equipped with another embodiment of the 3D sensor according to this embodiment, the processing of measurement algorithms using the random dot pattern 311, the processing of measurement algorithms using the stripe pattern 312, etc., are also performed not by the 3D sensor 3, but by the robot control device 2.

[0027] Specifically, for example, multiple project patterns such as a random dot pattern (first project pattern) and a striped pattern (second project pattern), as well as image processing programs for processing images captured from stereo cameras 32a and 32b, are stored in the storage device 23 of the robot control device 2. Furthermore, the processing of the measurement algorithm using the random dot pattern 311 (first measurement algorithm) and the measurement algorithm using the striped pattern 312 (second measurement algorithm), as well as the selection of the project pattern to be projected from the projector 31 onto the workpiece W and the selection of the measurement algorithm corresponding to the selected project pattern, are performed by the robot control unit 22 (arithmetic processing unit of the robot control unit 22).

[0028] Alternatively, the 3D image processing unit 30(20) may be provided on both the 3D sensor 3 and the robot control device 2, with some processing performed by the 3D sensor 3 and the remaining processing performed by the robot control device 2. Furthermore, for example, the 3D sensor 3 can be connected to the robot control device 2 via an image processing device, and the 3D image processing unit 30 can be provided on the image processing device for processing. In addition, some processing can be performed on the 3D sensor 3 and the remaining processing on the image processing device.

[0029] Figure 6 is a flowchart illustrating an example of processing in one embodiment of the three-dimensional measurement method according to this embodiment, and shows an example of processing in the three-dimensional measurement method to which a random dot pattern 311 and a stripe pattern 312 are applied.

[0030] As shown in Figure 6, when an example of the processing in one embodiment of the three-dimensional measurement method according to this embodiment starts, in step ST1, the random dot pattern 311 is stereo-measured. That is, in step ST1, the random dot pattern 311 is projected onto the workpiece W from the projector 31 of the three-dimensional sensor 3, and an image of the workpiece W onto which the random dot pattern 311 is projected is captured by a pair (two) stereo cameras 32a and 32b provided on both sides of the projector 31, and the process proceeds to step ST2.

[0031] In step ST2, a correspondence is made between two images captured by stereo cameras 32a and 32b, that is, a three-dimensional measurement of the workpiece W is performed using the random dot pattern 311. Specifically, in step ST2, areas with similar patterns are searched for in the images obtained by each camera 32a and 32b, and a correspondence is made between pixels in the images (between cameras) (first correspondence).

[0032] Here, the image mapping process in step ST2 can be performed by a 3D image processing unit 30, which includes a storage unit 33 and a processing unit 34 built into the 3D sensor 3, as explained with reference to Figures 1 to 3. Alternatively, the image mapping process in step ST2 can also be performed by a 3D image processing unit (vision sensor control unit) 20 provided in the robot control device 2, as explained with reference to Figure 5.

[0033] In one embodiment of the three-dimensional measurement method according to this embodiment, after three-dimensional measurement of the workpiece W using the random dot pattern 311 in steps ST1 and ST2, for example, three-dimensional measurement of the workpiece W is performed by projecting a stripe pattern 312 onto the workpiece W a predetermined number of times (for example, n times) while finely shifting the stripes left and right (changing the phase). That is, after matching the images in step ST2, the process proceeds to step ST3 where i=1 is set, and then to step ST4 where the stripe pattern 312 is measured in stereo.

[0034] Furthermore, the process proceeds to step ST5 to determine whether i=n is true. If it is determined that i=n is not true (No), that is, if it is determined that the number of 3D measurements of the workpiece W performed by projecting the stripe pattern 312 is less than the predetermined number (n), the process proceeds to step ST6. In step ST6, the stripe pattern 312 projected onto the workpiece W is shifted left or right. Then, the process proceeds to step ST7, where i=i+1 is incremented, and the process returns to step ST4 to perform stereo measurement of the stripe pattern 312.

[0035] On the other hand, if it is determined in step ST5 that i = n is true (Yes), that is, if it is determined that the predetermined number of times (n) the 3D measurement of the workpiece W performed by changing the phase of the stripe pattern 312 has been reached, the process proceeds to step ST8 to perform re-correspondence between each acquired image. Specifically, in step ST8, pixels with similar brightness value distributions are searched for in the vicinity of the corresponding pixels obtained in the first correspondence based on the random dot pattern 311 between the stereo cameras 32a and 32b, and the correspondence between pixels between the cameras is determined with higher precision (a second correspondence is performed), and the process proceeds to step ST9.

[0036] In step ST9, based on the results of the re-correspondence in step ST8, the distance to each pixel is calculated using the principle of triangulation, that is, the three-dimensional shape of the workpiece W using the random dot pattern 311 and the stripe pattern 312 is measured, and an example of the processing in one embodiment of the three-dimensional measurement method according to this embodiment is completed (END).

[0037] The 3D measurement images based on the 3D image generated using the random dot pattern 311 and the 3D image generated using the stripe pattern 312 are input to, for example, the 3D image acquisition unit 21 of the robot control device 2. Furthermore, as explained with reference to Figure 3, the above processing can be performed by the 3D image processing unit 30 (processing unit 34) of the 3D sensor 3, but as mentioned above, the 3D image processing unit 30 can be removed from the 3D sensor 3, and instead, a 3D image processing unit 20 equivalent to the 3D image processing unit 30 can be provided in the robot control device 2.

[0038] In the flowchart shown in Figure 6, as shown in step ST6, the stripe pattern 312 projected onto the workpiece W is shifted left and right to perform multiple 3D measurements using the stripe pattern 312. However, various methods can be applied to the process in step ST6, such as changing the width of the stripes or changing the direction of the stripes. Furthermore, although the flowchart shown in Figure 6 is intended to explain an example of the processing of a 3D measurement method that applies a random dot pattern 311 and a stripe pattern 312, the 3D measurement method according to this embodiment is not limited to applying a random dot pattern 311 and a stripe pattern 312. For example, a project pattern used in the optical section method (laser section method) or various other 3D measurement methods may also be used. Thus, according to one embodiment of the 3D measurement method according to this embodiment, it becomes possible to determine the 3D shape of the workpiece W with high precision in a short time.

[0039] The three-dimensional measurement method according to the embodiment described above can be implemented as a program (three-dimensional measurement program) that causes a computer (processing unit) to execute processing. This three-dimensional measurement program may also be provided by recording it on a computer-readable non-temporary recording medium or a non-volatile semiconductor memory, and can also be provided via wired or wireless connection. Examples of computer-readable non-temporary recording media include optical discs such as CD-ROMs (Compact Disc Read Only Memory) and DVD-ROMs, or hard disk drives. Examples of non-volatile semiconductor memory include PROMs (Programmable Read Only Memory) and flash memory. Distribution from a server device can be via a wired or wireless LAN (Local Area Network), or via a WAN such as the Internet. The program (computer program) may also be provided in the form of a computer program product.

[0040] As described in detail above, the three-dimensional sensor, robot system, and three-dimensional measurement method according to this embodiment make it possible to determine the three-dimensional shape of a work object with high precision in a short amount of time.

[0041] While this disclosure has been described in detail, it is not limited to the individual embodiments described above. These embodiments can be added, replaced, modified, partially deleted, etc., in any way that does not depart from the gist of this disclosure or from the spirit of this disclosure derived from the claims and their equivalents. Furthermore, these embodiments can be implemented in combination. For example, the order of operations and processes in the embodiments described above are given as examples only and are not limited thereto. The same applies when numerical values ​​or mathematical formulas are used in the description of the embodiments described above.

[0042] With respect to the above embodiments and modifications, the following additional notes are disclosed. [Addendum 1] A three-dimensional sensor comprising: a projector (31) that projects multiple types of project patterns onto a work object (W); and cameras (32a, 32b) that image the work object (W) onto which the project patterns are projected, wherein the project patterns include a first project pattern (311) that performs three-dimensional measurement of the work object (W) according to a first measurement algorithm, and a second project pattern (312) that performs three-dimensional measurement of the work object (W) according to a second measurement algorithm. [Addendum 2] The three-dimensional sensor according to Addendum 1, wherein the first project pattern (311) and the first measurement algorithm perform three-dimensional measurement of the work object (W) in a shorter time than the second project pattern (312) and the second measurement algorithm. [Note 3] The 3D sensor according to Note 1 or Note 2, wherein the second project pattern (312) and the second measurement algorithm perform 3D measurement of the work object (W) with higher precision than the first project pattern (311) and the first measurement algorithm. [Note 4] The 3D sensor according to any one of Notes 1 to 3, wherein the first project pattern (311) and the first measurement algorithm, and the second project pattern (312) and the second measurement algorithm are selectable. [Note 5] The 3D sensor according to any one of Notes 1 to 4, wherein the first measurement algorithm performs 3D measurement of the work object (W) based on imaging processing using one type of the first project pattern (311), and the second measurement algorithm performs 3D measurement of the work object (W) based on imaging processing using multiple types of the second project pattern (312). [Note 6] The three-dimensional measurement of the work object (W) by the first measurement algorithm is performed before the three-dimensional measurement of the work object (W) by the second measurement algorithm, as described in any one of Notes 1 to 5.[Note 7] The three-dimensional sensor according to any one of Notes 1 to 6, wherein the first measurement algorithm performs three-dimensional measurement of the work object (W) based on imaging processing using the first project pattern (311), and the second measurement algorithm performs three-dimensional measurement of the work object (W) based on the three-dimensional measurement result of the first measurement algorithm and imaging processing using the second project pattern (312). [Note 8] The three-dimensional sensor according to any one of Notes 1 to 7, wherein the first project pattern is a random dot pattern (311), and the second project pattern is a stripe pattern (312). [Note 9] The three-dimensional sensor according to any one of Notes 1 to 8, wherein the camera is a stereo camera (32a, 32b). [Note 10] The three-dimensional sensor according to any one of Notes 1 to 9, further comprising: a storage unit (33) for storing the first project pattern (311) and the second project pattern (312); and a processing unit (34) for performing processing of the first measurement algorithm using the first project pattern (311) and processing of the second measurement algorithm using the second project pattern (312). [Note 11] The three-dimensional sensor according to any one of Notes 1 to 9, wherein the storage of the first project pattern (311) and the second project pattern (312), and the processing of the first measurement algorithm and the processing of the second measurement algorithm are performed by a control device (2) to which the three-dimensional sensor is connected. [Appendix 12] A robot system comprising: a three-dimensional sensor (3) described in any one of the appendices 1 to 11; a robot (1) that performs a predetermined operation on the work object (W); and a robot control device (2) that acquires a three-dimensional image of the work object (W) based on the output of the three-dimensional sensor and controls the robot to perform a predetermined operation on the work object (W).[Note 13] A three-dimensional measurement method comprising projecting multiple types of project patterns (311, 312) onto a work object (W), and imaging the work object (W) onto which the project patterns are projected with cameras (32a, 32b) to measure the three-dimensional shape of the work object (W), wherein the project patterns include a first project pattern (311) that performs three-dimensional measurement of the work object (W) according to a first measurement algorithm, and a second project pattern (312) that performs three-dimensional measurement of the work object (W) according to a second measurement algorithm. [Note 14] The three-dimensional measurement method according to Note 13, wherein the first project pattern (311) and the first measurement algorithm perform three-dimensional measurement of the work object (W) in a shorter time than the second project pattern (312) and the second measurement algorithm. [Note 15] The three-dimensional measurement method according to Note 13 or Note 14, wherein the second project pattern (312) and the second measurement algorithm perform three-dimensional measurement of the work object (W) with higher precision than the first project pattern (311) and the first measurement algorithm. [Note 16] The three-dimensional measurement method according to any one of Notes 13 to 15, wherein the first project pattern (311) and the first measurement algorithm, and the second project pattern (312) and the second measurement algorithm are selectable. [Note 17] The three-dimensional measurement method according to any one of Notes 13 to 16, wherein the first measurement algorithm performs three-dimensional measurement of the work object (W) based on imaging processing using one type of the first project pattern (311), and the second measurement algorithm performs three-dimensional measurement of the work object (W) based on imaging processing using multiple types of the second project pattern (312). [Note 18] The three-dimensional measurement method according to any one of Notes 13 to 17, wherein the three-dimensional measurement of the work object (W) by the first measurement algorithm is performed before the three-dimensional measurement of the work object (W) by the second measurement algorithm.[Note 19] The three-dimensional measurement method according to any one of Notes 13 to 18, wherein the first measurement algorithm performs three-dimensional measurement of the work object (W) based on imaging processing using one type of first project pattern (311), and the second measurement algorithm performs three-dimensional measurement of the work object (W) based on the three-dimensional measurement result of the first measurement algorithm and imaging processing using multiple types of second project patterns (312). [Note 20] The three-dimensional measurement method according to any one of Notes 13 to 19, wherein the first project pattern is a random dot pattern (311), and the second project pattern is a stripe pattern (312).

[0043] 1 Robot 2 Robot control unit 3 3D sensor (vision sensor) 11 Arm unit 12 End effector (work tool) 20 3D image processing unit (vision sensor control unit) 21 3D image acquisition unit 22 Robot control unit 23 Storage unit 31 Projector 32a, 32b Camera 33 Memory unit 34 Processing unit 100 Robot system 300 Captured image 311 Random dot pattern (random pattern) 312 Stripe pattern F Installation floor W Workpiece

Claims

1. A three-dimensional sensor comprising: a projector that projects multiple types of project patterns onto a work object; and a camera that captures images of the work object onto which the project patterns are projected, wherein the project patterns include a first project pattern that performs three-dimensional measurement of the work object according to a first measurement algorithm, and a second project pattern that performs three-dimensional measurement of the work object according to a second measurement algorithm.

2. The three-dimensional sensor according to claim 1, wherein the first project pattern and the first measurement algorithm perform three-dimensional measurement of the work object in a shorter time than the second project pattern and the second measurement algorithm.

3. The three-dimensional sensor according to claim 1 or 2, wherein the second project pattern and the second measurement algorithm perform three-dimensional measurement of the work object with higher accuracy than the first project pattern and the first measurement algorithm.

4. The three-dimensional sensor according to any one of claims 1 to 3, wherein the first project pattern and the first measurement algorithm, and the second project pattern and the second measurement algorithm are selectable.

5. The three-dimensional sensor according to any one of claims 1 to 4, wherein the first measurement algorithm performs three-dimensional measurement of the work object based on imaging processing using one type of first project pattern, and the second measurement algorithm performs three-dimensional measurement of the work object based on imaging processing using multiple types of second project patterns.

6. The three-dimensional sensor according to any one of claims 1 to 5, wherein the three-dimensional measurement of the work object by the first measurement algorithm is performed before the three-dimensional measurement of the work object by the second measurement algorithm.

7. The three-dimensional sensor according to any one of claims 1 to 6, wherein the first measurement algorithm performs three-dimensional measurement of the work object based on imaging processing by the first project pattern, and the second measurement algorithm performs three-dimensional measurement of the work object based on the three-dimensional measurement result of the first measurement algorithm and imaging processing by the second project pattern.

8. The three-dimensional sensor according to any one of claims 1 to 7, wherein the first projection pattern is a random dot pattern, and the second projection pattern is a striped pattern.

9. The three-dimensional sensor according to any one of claims 1 to 8, wherein the camera is a stereo camera.

10. A three-dimensional sensor according to any one of claims 1 to 9, further comprising: a storage unit for storing the first project pattern and the second project pattern; and a processing unit for performing processing of the first measurement algorithm using the first project pattern and processing of the second measurement algorithm using the second project pattern.

11. The storage of the first project pattern and the second project pattern, and the processing of the first measurement algorithm and the processing of the second measurement algorithm are performed by a control device to which the three-dimensional sensor is connected, as described in any one of claims 1 to 9.

12. A robot system comprising: a three-dimensional sensor according to any one of claims 1 to 11; a robot that performs a predetermined operation on the work object; and a robot control device that acquires a three-dimensional image of the work object based on the output of the three-dimensional sensor and controls the robot to perform a predetermined operation on the work object.

13. A three-dimensional measurement method comprising projecting multiple types of project patterns onto a work object, and measuring the three-dimensional shape of the work object by imaging the work object onto which the project patterns are projected with a camera, wherein the project patterns include a first project pattern for performing three-dimensional measurement of the work object according to a first measurement algorithm, and a second project pattern for performing three-dimensional measurement of the work object according to a second measurement algorithm.

Images