Work taking method and work taking system

Abstract

A workpiece picking method for picking workpieces supplied onto a supply stage in a dispersed manner, the supply stage being wider than an image capturing range corresponding to the angle of view of an image capturing unit, the workpiece picking method comprising: (a) a step for performing, in each of a plurality of regions of the supply stage divided on the basis of the image capturing range, a picking process for selecting a pickable workpiece on the basis of an image of the region captured by the image capturing unit, and causing a picking unit to pick the workpiece; (b) a step for acquiring, for each region, a remaining number of workpieces remaining after the picking process; (c) a step for supplying new workpieces onto the supply stage and performing a disentangling operation for disentangling a mass of workpieces, or performing the disentangling operation without supplying new workpieces, on the basis of the remaining number of workpieces in each region; and (d) a step for performing a picking process, after the disentangling operation, in a largest-number region in which the remaining number of workpieces acquired for each of the regions after the picking process is largest.

Description

Technical Field

[0001] This specification discloses a work picking method and a work picking system.

Background Art

[0002] Conventionally, a method has been proposed in which a work supplied in a scattered state on a supply stage is imaged by an imaging unit, a pickable work is selected, and then picked up by a robot. For example, in Patent Document 1, the entire plate as a supply stage is configured to be uniformly vibratable, and the work is dispersed over the entire surface of the plate by vibration and then picked up by the robot, so that the entire surface of the plate is effectively utilized to efficiently pick up the work.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] Here, there are cases where the supply stage (plate) is wider than the imaging range corresponding to the angle of view of the imaging unit. In that case, using an imaging unit with a wide imaging range according to the supply stage lacks versatility and is disadvantageous in terms of cost. Also, it may be possible to image the supply stage in a plurality of regions divided based on the imaging range, and combine the captured images to create an overall image, but this increases the burden of image processing. Therefore, it is conceivable to perform the process of imaging the image and picking up the work for each region, but depending on the state of dispersion of the work, there may be cases where a region without work is imaged, and there is a risk of a decrease in processing efficiency.

[0005] The main object of the present disclosure is to efficiently pick up work from a supply stage wider than the imaging range of the imaging unit.

Means for Solving the Problems

[0006] To achieve the above main object, the present disclosure adopts the following means.

[0007] The first workpiece picking method of the present disclosure is a workpiece picking method for picking up workpieces supplied in a scattered state on a supply stage wider than the imaging range corresponding to the angle of view of the imaging unit, (a) performing a picking process of selecting pickable workpieces based on an image obtained by imaging the area by the imaging unit in each of a plurality of areas obtained by dividing the supply stage based on the imaging range, and causing the picking unit to pick them up; (b) obtaining the remaining number of workpieces remaining in each area after the picking process; (c) based on the remaining number of workpieces in each area, causing a loosening operation to loosen a mass of workpieces by newly supplying workpieces to the supply stage, or causing the loosening operation without newly supplying workpieces; (d) performing the picking process after the loosening operation in the area with the largest number of remaining workpieces in each area obtained after the picking process; and is characterized by including the above.

[0008] In the first workpiece picking method of the present disclosure, based on the remaining number of workpieces in each area remaining after the picking process, a loosening operation is caused by newly supplying workpieces to the supply stage, or the loosening operation is caused without newly supplying workpieces. Also, in the area with the largest number of remaining workpieces after the picking process, the picking process after the loosening operation is performed. Since the area that was the area with the largest number of remaining workpieces before the loosening operation is likely to still have a relatively large number of workpieces after the loosening operation, it is possible to prevent inefficient processes such as performing a picking process on an area with few pickable workpieces or wasteful processes such as imaging an image of an area where there are no workpieces. Therefore, it is possible to efficiently pick up workpieces from a supply stage wider than the imaging range of the imaging unit.

Brief Description of the Drawings

[0009]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Mode for Carrying Out the Invention

[0010] Next, embodiments of the present disclosure will be described with reference to the drawings. FIG. 1 is a configuration diagram showing an overview of the configuration of the work system 10. FIG. 2 is a block diagram showing the electrical connection relationship of the work system 10. In FIG. 1, the left - right direction is the X - axis direction, the front - rear direction is the Y - axis direction, and the up - down direction is the Z - axis direction.

[0011] As shown in FIGS. 1 and 2, the work system 10 includes a work supply device 20 (20A, 20B), a tray conveyance device 30, a work robot 40, a camera 45, and a control device 50. The work system 10 performs predetermined work such as pick - and - place of workpieces using the work robot 40. For example, the work robot 40 of the work system 10 picks up the bolts B (first workpieces) supplied in a scattered state, turns the head downward, and arranges them on the tray T in an upright posture, and picks up the washers W (second workpieces) supplied in a scattered state and arranges them so as to be inserted into the screw portion (rod - shaped portion) of the bolts B on the tray T. Note that the work system 10 is not limited to pick - and - place, and for example, as long as it can sequentially cause the work robot 40 to pick up the supplied workpieces such as picking up a workpiece and attaching it to an object.

[0012] The working system 10 of this embodiment includes, as a work supply device 20, a first work supply device 20A that supplies bolts B and a second work supply device 20B that supplies washers W. Since the first work supply device 20A and the second work supply device 20B have the same configuration, they will be simply described as the work supply device 20 below. Note that the work supply device 20 may supply works such as various mechanical parts like bolts B and washers W, as well as various electronic parts. Also, the working system 10 is not limited to including two work supply devices 20A and 20B, and may include only one work supply device 20. Further, the working system 10 may include a work robot 40 corresponding to the number of work supply devices 20.

[0013] The work supply device 20 includes a feeding unit 22 that sends the work input by an operator or a replenishment robot (not shown) forward, a supply stage 25 where the work robot 40 is arranged so as to be able to collect the work, and a vibration device 26 (see FIG. 2) that vibrates the supply stage 25 vertically.

[0014] The feeding unit 22 has a first inclined portion 22a, a second inclined portion 22b, and a third inclined portion 22c, and includes a lifting device 23 (see FIG. 2) that moves the second inclined portion 22b up and down. The first inclined portion 22a, the second inclined portion 22b, and the third inclined portion 22c are provided in this order from the rear, and all are inclined downward toward the front lower side. The second inclined portion 22b is located at the lower end of the lifting range when the lifting device 23 is not operating, and its upper surface is continuous with the upper surface of the first inclined portion 22a. When the lifting device 23 is operating, it is located at the upper end of the lifting range, and its upper surface is continuous with the upper surface of the third inclined portion 22c. The third inclined portion 22c is provided such that its front end extends above the rear end of the supply stage 25. Although not shown, a rear wall extending downward from the rear end of the second inclined portion 22b is provided. Even when the second inclined portion 22b rises, the work on the first inclined portion 22a is blocked by the rear wall of the second inclined portion 22b. Also, a rear wall extending downward from the rear end of the third inclined portion 22c is provided, and the work on the second inclined portion 22b located at the lower end is blocked by the rear wall of the third inclined portion 22c.

[0015] The workpiece loaded into the workpiece supply device 20 flows forward and downward on the first inclined portion 22a and stays on the second inclined portion 22b. When the upper surface of the second inclined portion 22b that has risen due to the operation of the lifting device 23 is continuous with the upper surface of the third inclined portion 22c, the workpiece staying on the second inclined portion 22b flows to the third inclined portion 22c and drops onto the supply stage 25. In this way, the workpiece supply device 20 supplies the workpieces in a scattered state onto the supply stage 25, enabling the work robot 40 to pick up the workpieces on the supply stage 25. Further, the workpiece supply device 20 can loosen (separate) the workpiece mass by driving the vibration device 26 to apply vibration to the workpieces on the supply stage 25. This operation is called the loosening operation.

[0016] The tray conveyor 30 has a pair of belt conveyors 32 that are spaced apart in the front-rear direction (Y-axis direction) and span in the left-right direction (X-axis direction). The tray conveyor 30 conveys the tray T to the working area of the work robot 40 by driving the belt conveyor 32.

[0017] The work robot 40 includes, for example, a vertically articulated robot arm 42 and an end effector 44 that is detachably attached to the tip link of the robot arm 42. The end effector 44 is for picking up the workpiece and is composed of an electromagnetic chuck, a mechanical chuck, a suction nozzle, etc., and is appropriately selected according to the shape and material of the workpiece.

[0018] In addition, a camera 45 for imaging is also attached to the robot arm 42. The camera 45 is equipped with a single-focus lens and has a constant angle of view. This camera 45 images the workpiece to recognize the position, number, and posture of the workpiece supplied to the supply stage 25, or images the tray T to recognize the position of the tray T conveyed by the tray conveyor 30.

[0019] FIG. 3 is an explanatory diagram showing the relationship between the imaging range FC of the camera 45 and the supply stage 25. In FIG. 3, the area of the supply stage 25 viewed from above is shown by a solid line, and the imaging range FC is shown by a dotted line. Also, a state in which a plurality of washers W are supplied onto the supply stage 25 is illustrated. The imaging range FC is a range determined on the supply stage 25 based on the angle of view of the camera 45, and in this embodiment, substantially coincides with the area obtained by dividing the supply stage 25 into two regions on the left and right. Therefore, in order to image the entire area of the supply stage 25 with the camera 45, it is necessary to perform imaging twice. That is, the camera 45 needs to image the first region (for example, the left region) while being positioned above the first region by the operation of the robot arm 42, and image the second region (for example, the right region) while being positioned above the second region by the operation of the robot arm 42.

[0020] As shown in FIG. 2, the control device 50 is configured as a microprocessor centered on the CPU 51. In addition to the CPU 51, the control device 50 includes a ROM 52 that stores various control programs, a RAM 53 used as a work area, an HDD 54 that stores various data, and input / output ports (not shown). Detection signals from sensors (not shown) provided in the work supply device 20, the tray transport device 30, and the work robot 40, images captured by the camera 45, etc. are input to the control device 50. Further, control signals are output from the control device 50 to the work supply device 20, the tray transport device 30, the work robot 40 (the robot arm 42 and the end effector 44), the camera 45, etc.

[0021] Next, the operation of the work system 10 configured in this way, particularly the process when imaging the work on the supply stage 25, selecting a work that can be picked up, and causing the work robot 40 to pick it up, will be described. FIG. 4 is a flowchart showing an example of a work process routine. As an example of the work process, the left region of the supply stage 25 is defined as the first region, the right region as the second region, and the process when picking up the washer W will be described.

[0022] In the operation processing routine of FIG. 4, the CPU 51 of the control device 50 first controls the work robot 40 so that the camera 45 moves to the imaging position in the first area (S100), and executes the work collection process in the first area (S105). When the work collection process in the first area is completed, the CPU 51 controls the work robot 40 so that the camera 45 moves to the imaging position in the second area (S110), and executes the work collection process in the second area (S115). Hereinafter, the work collection processes of S105 and S115 will be described. FIG. 5 is a flowchart showing an example of the work collection process. Since the work collection processes of S105 and S115 are the same processes although the target areas of the processes are different, a common flowchart will be used for the description.

[0023] In the work collection process of FIG. 5, the CPU 51 first controls the camera 45 to image the image of the target area (S200). In the case of S105, the image of the first area is imaged, and in the case of S115, the image of the second area is imaged. Next, the CPU 51 processes the captured image to recognize the number of workpieces, positions, etc. (S205). In the case where the workpiece to be collected is a bolt B or the like, the posture of the workpiece is also recognized. Subsequently, the CPU 51 determines whether there is a workpiece that can be collected (S210). In S210, for example, since there is no other workpiece overlapping and no other workpiece or the peripheral wall of the supply stage 25 is not close to the surroundings, a workpiece that can be gripped by the end effector 44 such as a mechanical chuck is determined to be collectable. When the CPU 51 determines that there is a workpiece that can be collected, it collects the workpiece and arranges it at a predetermined location (S215), increments the collection count by a value of 1 (S220), and returns to S210. In the case of the washer W, in S215, it is arranged to be inserted into the screw portion of the bolt B as described above.

[0024] Also, when the CPU 51 determines that there is no work that can be collected in S210, it stores the remaining number of workpieces R (S225) and ends the workpiece collection process. The remaining number of workpieces R is obtained by subtracting the number of collected workpieces incremented in S220 from the number of workpieces recognized in S205. Also, let the remaining number R stored in the workpiece collection process in the first area of S105 be the remaining number R1, and the remaining number R stored in the workpiece collection process in the second area of S115 be the remaining number R2.

[0025] FIG. 6 is an explanatory diagram showing an example of the change in the remaining number of workpieces R. FIG. 6(a) shows the state after the workpiece collection process in the first area (left area) of S105 is executed from the state of FIG. 3. For example, the remaining number R1 in the first area is 6. FIG. 6(b) shows the state after the workpiece collection process in the second area (right area) of S115 is executed from the state of FIG. 6(a). For example, the remaining number R2 in the second area is 8.

[0026] In the work process routine of FIG. 4, when the CPU 51 executes the workpiece collection process of S115, it calculates the total number Sa as the total number S of the remaining number R (S120). The total number Sa is the total number of workpieces remaining on the supply stage 25 after the workpiece collection process is executed in each area, and is the sum of the remaining number R1 in the first area and the remaining number R2 in the second area. Also, in the example of FIG. 6, it becomes 14 (FIG. 6(b)). Subsequently, the CPU 51 determines whether the total number Sa is equal to or greater than a predetermined number Sref (S125). The predetermined number Sref may be a value that can be appropriately set by the operator according to the size of the supply stage 25, the type of workpiece, etc., or may be a fixed value. When the CPU 51 determines that the total number Sa is equal to or greater than the predetermined number Sref, since relatively many workpieces remain, it controls the workpiece supply device 20 so as to perform a loosening operation on the workpieces on the supply stage 25 without newly supplying workpieces to the supply stage 25 (S130) and proceeds to S140. On the other hand, when the CPU 51 determines that the total number Sa is less than Sref and not equal to or greater than Sref, it controls the workpiece supply device 20 so as to perform a loosening operation on the workpieces after newly supplying workpieces to the supply stage 25 (S135) and proceeds to S140.

[0027] Next, when calculating the total number S (Sa or Sb described later), the CPU 51 discriminates a majority area with a large remaining number R and a minority area (remaining number Rf) with a small remaining number R (S140). In the example of FIG. 6, since the remaining number R2 in the second area is larger than the remaining number R1 in the first area (FIG. 6(b)), the second area is the majority area and the first area is the minority area. Also, in S140, the CPU 51 stores the value 6 of the remaining number R1 in the first area as the remaining number Rf of the minority area. Then, the CPU 51 controls the work robot 40 so that the camera 45 moves to the imaging position of the majority area (S145) and executes the work collection process for the majority area (S150). That is, before performing the loosening operation of the work in S130 or before performing the work supply and the loosening operation in S135, the CPU 51 performs the work collection process with the majority area having a larger remaining number R as the next processing target. Although the work may move between areas due to the loosening operation, it can be said that the movement from the first area to the second area and the movement from the second area to the first area occur in the same way. Therefore, in S140 and S150, without particularly considering the change in the remaining number R due to the movement of the work between areas, the majority area after the previous work collection process is set as the next processing target. Also, the work collection process in S150 is executed based on the flowchart of FIG. 5, similar to S105 and S115, so the description is omitted. Also, let the remaining number R after the work collection process in S150 be the remaining number Rm. In the example of FIG. 6, since the second area is the majority area, the work collection process for the second area is executed (FIG. 6(c), (d)). Since the work collection process for the first area, which was set as the minority area in S140, is not executed, the remaining number Rf remains the value 6.

[0028] When the work collection process in S150 is executed, the CPU 51 calculates the total number Sb as the total number S of the remaining number R (S155). The total number Sb is the sum of the remaining number Rm after the work collection process in the majority area and the remaining number Rf in the minority area. In the example of FIG. 6, since the remaining number Rm in the second area, which is the majority area, becomes, for example, the value 4, and the remaining number Rf in the first area, which is the minority area, remains the value 6, the total number Sb becomes the value 10 (FIG. 6(d)). In this example, the remaining number Rf in the first area is larger than the remaining number Rm in the second area.

[0029] Subsequently, the CPU 51 determines whether the total number Sb is equal to or greater than a predetermined number Sref (S160). The predetermined number Sref in S160 is the same as the predetermined number Sref in S125, but it may be a different number. If the CPU 51 determines that the total number Sb is equal to or greater than the predetermined number Sref, the CPU 51 controls the workpiece supply device 20 to perform a loosening operation on the workpiece on the supply stage 25 without newly supplying a workpiece to the supply stage 25 (S165), and proceeds to S140. If the CPU 51 determines in S160 that the total number Sb is less than the predetermined number Sref and less than Sref, the CPU 51 controls the workpiece supply device 20 to newly supply a workpiece to the supply stage 25 and then perform a loosening operation on the workpiece (S170), and proceeds to S100. That is, in this case, the collection process is executed again in the order of the first region and the second region.

[0030] In S140 executed after S165, the CPU 51 discriminates between a majority region with a large remaining number R and a minority region (remaining number Rf) with a small remaining number R when calculating the total number Sb, and executes the processes after S145. That is, a workpiece collection process is executed for the majority region when the total number Sb is calculated in S155. In the example of FIG. 6, as shown in FIG. 6(d), since the first region is the majority region and the second region is the minority region, the remaining number Rf becomes the value 4 of the remaining number R of the second region, and the workpiece collection process of the first region is executed. Although not shown, when the collection process of the first region is executed in S145 and S155, the remaining number R of the first region becomes the remaining number Rm. The CPU 51 calculates the total number Sb of the remaining number Rm and the remaining number Rf (value 4) of the second region in S155. In this way, when collecting the required number of workpieces from the supply stage 25 while selecting the target region (majority region) and executing the workpiece collection process of the target region, the work process routine ends.

[0031] Here, the correspondence between the components of this embodiment and the components of the present disclosure will be clarified. S105 and S115 (excluding S225 in FIG. 2) of the work processing routine of this embodiment correspond to step (a), S225 in FIG. 2 when performing S105 and S115 corresponds to step (b), S120 to S135 of the work processing routine correspond to step (c), and S140, S145, and S150 (excluding S225 in FIG. 2) of the work processing routine correspond to step (d). S225 in FIG. 2 when performing S150 corresponds to step (e), and S155 to S170 of the work processing routine correspond to step (f). Further, the camera 45 corresponds to the imaging unit, the supply stage 25 of the work supply device 20 corresponds to the supply stage, the work robot 40 corresponds to the collection unit, the feeding unit 22 (lifting device 23) of the work supply device 20 corresponds to the supply unit, the vibration device 26 of the work supply device 20 corresponds to the loosening unit, and the control device 50 corresponds to the control unit.

[0032] As described above, in the work collection method of the present disclosure, based on the remaining number R (R1, R2) of work for each area after the work collection process, the work is supplied to perform the loosening operation, or the loosening operation is performed without supplying the work. Further, before the loosening operation (when calculating the total number S), the work collection process after the loosening operation is performed for a large number of areas where the remaining number R of work is large. In a large number of areas, it is highly likely that there is still a relatively large amount of work even after the loosening operation. Therefore, by performing the work collection process for a large number of areas after the loosening operation, it is possible to prevent inefficient work collection processes in areas with a small amount of work and wasteful imaging processes in areas where there is no work. Also, since there is no need to perform processes such as imaging the images of each area and determining the target area after the loosening operation, the cycle time can be shortened.

[0033] Also, based on the remaining number Rm after performing the work collection process in a large number of areas and the remaining number Rf in a small number of areas, the loosening operation is performed after supplying the work or the loosening operation is performed without supplying the work. That is, after performing the work collection process in a large number of areas, the next process can be moved without imaging the images of the small number of areas, so the imaging process can be omitted and the cycle time can be shortened.

[0034] Also, when the workpiece is supplied and then the loosening operation is performed after the workpiece collection process for multiple regions, since it proceeds to S100, if there is a high possibility that workpieces that can be collected exist in each region due to the supply of the workpiece, the workpiece collection process for each region can be sequentially performed. On the other hand, when the loosening operation is performed without supplying the workpiece after the workpiece collection process for multiple regions, since it proceeds to S140, multiple regions can be reselected and the workpiece collection process for those multiple regions can be performed. Therefore, if there may be regions with few collectable workpieces or no existing workpieces because the workpiece was not supplied, inefficient workpiece collection processes and wasted imaging processes can be prevented by performing the workpiece collection process in multiple regions.

[0035] Note that the present disclosure is not limited to the above-described embodiments, and it goes without saying that various embodiments can be implemented as long as they belong to the technical scope of the present disclosure.

[0036] In the above-described embodiment, when the workpiece is supplied and then the loosening operation is performed after the workpiece collection process for multiple regions (when S170 is executed), it proceeds to S100, but it is not limited to this. FIG. 7 is a flowchart showing a work processing routine of a modified example. The work processing routine of the modified example is different from the embodiment in that it proceeds to S140 instead of S100 after executing S170. As a result, when the loosening operation is performed at S165 and S170, multiple regions can be reselected and the workpiece collection process for those multiple regions can be performed. That is, since the workpiece collection process for multiple regions can be repeatedly performed, inefficient workpiece collection processes and wasted imaging processes can be prevented for regions with few collectable workpieces or no existing workpieces.

[0037] In the embodiment, in calculating the total number Sb in S155 after S165 is executed and the process proceeds to S140, the remaining number R of the majority region uses the actual remaining number Rm after the workpiece picking process, and the remaining number R of the minority region uses the remaining number Rf obtained before the loosening operation (when calculating the total number S), but it is not limited thereto. For example, the CPU 51 may image the minority region with the camera 45 to obtain the actual remaining number R. Also, when proceeding to S140 after S165 and S170 as in the above-described modification example, the following may be done. That is, after only the loosening operation is performed in S165, since the remaining number R for each region is unlikely to have changed, the CPU 51 may use the remaining number Rf obtained before the loosening operation as the remaining number R of the minority region. On the other hand, when the workpiece supply and the loosening operation are performed in S170, since the remaining number R for each region is likely to have changed, the CPU 51 may image the minority region with the camera 45 to obtain the actual remaining number R.

[0038] In the embodiment, based on the total number S (Sa, Sb) of the remaining number R of each region, the loosening operation is performed without supplying the workpiece, or the loosening operation is performed after supplying the workpiece, but it is not limited thereto. Based on the remaining number R of one region (majority region) to be the next processing target, the loosening operation may be performed without supplying the workpiece, or the loosening operation may be performed after supplying the workpiece. Also, in S125, the determination is made based on the total number S (Sa) of the remaining number R of each region, and in S160, the determination is made based on the remaining number Rm of the majority region. Thus, there may be cases where the determination is made based on the total number S of the remaining number R of each region and cases where the determination is made based on the remaining number R (remaining number Rm) of one region.

[0039] In the embodiment, an example is given in which the supply stage 25 is divided into two regions, the first region and the second region, but it is not limited thereto, and it may be divided into three or more regions. For example, the supply stage 25 may be divided into three regions, a left region, a central region, and a right region.

[0040] When dividing into n regions (n is plural) in this way, the work processing routine in FIG. 4 (FIG. 7) may be performed as follows. First, in S100 to S115, a work collection process is executed for each of the n regions, and in S120, the total number Sa of the remaining numbers R after the work collection process for each region is calculated. Then, in S125 to S135, in the same manner as in the embodiment, the total number Sa of the remaining numbers R is compared with a predetermined number Sref, and S130 or S135 is executed. In S140, the majority region is set as the region with the largest remaining number among the n regions, and the minority region is set as the region that is not the majority region, that is, the remaining (n - 1) other regions. Then, in S145 and S150, the work collection process for the majority region is executed, and in S155 to S170, the total number Sb of the remaining number Rm after the work collection process for the majority region and the remaining numbers of the other regions is calculated, and the total number Sb is compared with the predetermined number Sref, and S165 or S170 is executed. When the supply stage 25 is divided into three or more regions, it takes more time to capture images of each region than in the embodiment. Therefore, by applying the processing of the present disclosure, the effect of preventing inefficient work collection processing and unnecessary imaging processing is further enhanced. Also, after the loosening operation, it is not necessary to capture images of each region to determine the target region, and the effect of shortening the cycle time by omitting unnecessary imaging processing is also enhanced.

[0041] In the embodiment, the work supply device 20 includes the feeding unit 22 that sends the work to the supply stage 25 and the vibration device 26 that performs the loosening operation of the work on the supply stage 25, but it is not limited thereto. The work supply device 20 may include the supply stage 25 and the vibration device 26, and the work may be directly supplied onto the supply stage 25 by a replenishment robot or the like. Alternatively, the work supply device 20 may include only the supply stage 25, and a robot such as a replenishment robot may perform the loosening operation of the work.

[0042] Here, the work collection method of the present disclosure may be as follows. For example, in the first work collection method of the present disclosure, (e) a step of obtaining the remaining number of works remaining in the maximum area after the collection process in step (d); and (f) based on the remaining number of works obtained before the loosening operation in areas other than the maximum area and the remaining number of works in the maximum area obtained in step (e), after the collection process in step (d), a step of performing the loosening operation after newly supplying a work to the supply stage or performing the loosening operation without newly supplying a work may be included. In this way, after the collection process in the maximum area, it is possible to move to the next process without imaging the images of other areas, so that unnecessary processes such as imaging areas where there are no works can be prevented.

[0043] In the first work collection method of the present disclosure, when the loosening operation is performed after newly supplying a work in step (f), it may be shifted to step (a), and when the loosening operation is performed without newly supplying a work in step (f), it may be shifted to step (d). In this way, when there is a high possibility that there are works that can be collected in each area because a new work is supplied, it is possible to return to step (a) and sequentially perform the collection process for each area. Also, when there may be areas where there are few collectible works or areas where there are no works because the loosening operation is performed without newly supplying a work, unnecessary processes can be prevented by performing the collection process in the maximum area.

[0044] In the first work collection method of the present disclosure, when any of the loosening operations in step (f) is performed, it may be shifted to step (d). In this way, since the collection process in the maximum area will be repeated, unnecessary processes can be prevented.

[0045] The second workpiece picking method of the present disclosure is a workpiece picking method for picking up workpieces supplied in a scattered state on a supply stage wider than an imaging range corresponding to the angle of view of an imaging unit, including: (a) In each of two regions obtained by dividing the supply stage based on the imaging range, performing a picking process of selecting workpieces that can be picked up based on an image obtained by imaging the region by the imaging unit and causing a picking unit to pick them up; (b) obtaining the remaining number of workpieces remaining after the picking process for each region; (c) when the total number of remaining workpieces for each region is less than a predetermined number, supplying new workpieces to the supply stage and causing a loosening operation to loosen the workpiece mass, and when the total number is greater than or equal to the predetermined number, causing the loosening operation without supplying new workpieces; and (d) performing the picking process after the loosening operation in a majority region where the remaining number of workpieces for each region obtained after the picking process is larger.

[0046] In the second workpiece picking method of the present disclosure, similar to the first workpiece picking method, the picking process after the loosening operation is performed in a majority region where the remaining number of workpieces obtained before the loosening operation is larger, so that workpieces can be efficiently picked up from a supply stage wider than the imaging range of the imaging unit. In addition, in the second workpiece picking method, each step of the first workpiece picking method may be added.

[0047] The workpiece picking system of the present disclosure includes an imaging unit, a supply stage wider than the imaging range corresponding to the angle of view of the imaging unit, a supply unit for supplying workpieces onto the supply stage, a picking unit for picking up the workpieces supplied in a scattered state on the supply stage, a loosening unit for performing a loosening operation to loosen the clumps of workpieces on the supply stage, and a control unit. The control unit performs a picking process of selecting and picking up pickable workpieces based on the images of the regions obtained by imaging each of the plurality of regions obtained by dividing the supply stage based on the imaging range, and controls the imaging unit and the picking unit to perform the picking process. Based on the remaining number of workpieces in each region remaining after the picking process, the supply unit and the loosening unit are controlled to perform a loosening operation to supply new workpieces to the supply stage to loosen the clumps of workpieces, or to perform the loosening operation without supplying new workpieces. The gist is to control the imaging unit and the picking unit to perform the picking process after the loosening operation in the region with the largest number of remaining workpieces obtained for each region after the picking process.

[0048] In the workpiece picking system of the present disclosure, similar to the first workpiece picking method described above, the picking process after the loosening operation is performed in the region with the largest number of remaining workpieces after the picking process. Therefore, it is possible to efficiently pick up workpieces from a supply stage wider than the imaging range of the imaging unit. In addition, in the workpiece picking system, functions for realizing each step of the first workpiece picking method may be added.

Industrial Applicability

[0049] The present disclosure can be used in the technical field of systems for picking up and arranging workpieces.

Explanation of Reference Numerals

[0050] 10 Operating system, 20, 20A, 20B Work supply device, 22 Feeding unit, 22a First inclined part, 22b Second inclined part, 22c Third inclined part, 23 Lifting device, 25 Supply stage, 26 Vibration device, 30 Tray transfer device, 32 Conveyor belt, 40 Work robot, 42 Robot arm, 44 End effector, 45 Camera, 50 Control device, 51 CPU, 52 ROM, 53 RAM, 54 HDD, B Bolt, T Tray, W Washer.

Claims

1. A work collection method for collecting workpieces supplied in a scattered state on a supply stage that is wider than the imaging range corresponding to the angle of view of an imaging unit, comprising: (a) performing a collection process of selecting, in each of a plurality of regions obtained by dividing the supply stage based on the imaging range, workpieces that can be collected based on an image obtained by imaging the region with the imaging unit and causing a collection unit to collect the selected workpieces; (b) obtaining the remaining number of workpieces remaining after the collection process for each of the regions; (c) based on the remaining number of workpieces for each region, causing a loosening operation to loosen a mass of workpieces by newly supplying workpieces to the supply stage or causing the loosening operation without newly supplying workpieces; (d) performing the collection process after the loosening operation in the region with the largest remaining number of workpieces, which is the region with the largest remaining number of workpieces obtained for each region after the collection process; A work collection method including the above steps.

2. The work collection method according to claim 1, further comprising: (e) obtaining the remaining number of workpieces remaining in the region with the largest remaining number of workpieces after the collection process in step (d); and (f) based on the remaining number of workpieces obtained before the loosening operation in regions other than the region with the largest remaining number of workpieces and the remaining number of workpieces in the region with the largest remaining number of workpieces obtained in step (e), after the collection process in step (d), causing the loosening operation after newly supplying workpieces to the supply stage or causing the loosening operation without newly supplying workpieces. A work collection method including the above steps.

3. The work collection method according to claim 2, wherein: when the loosening operation is performed after newly supplying workpieces in step (f), the process proceeds to step (a), and when the loosening operation is performed without newly supplying workpieces in step (f), the process proceeds to step (d). A work collection method.

4. The work collection method according to claim 2, wherein: when any of the loosening operations in step (f) is performed, the process proceeds to step (d). A work collection method.

5. A work collection method for collecting workpieces supplied in a scattered state on a supply stage that is wider than the imaging range corresponding to the angle of view of an imaging unit, comprising: (a) performing a collection process of selecting, in each of two regions obtained by dividing the supply stage based on the imaging range, workpieces that can be collected based on an image obtained by imaging the region with the imaging unit and causing a collection unit to collect the selected workpieces; Step (b) of obtaining the remaining number of workpieces remaining after the picking process for each of the regions; Step (c) of, when the total number of remaining workpieces for each region is less than a predetermined number, supplying new workpieces to the supply stage to perform a loosening operation for loosening the mass of workpieces, and when the total number is greater than or equal to the predetermined number, performing the loosening operation without supplying new workpieces; Step (d) of performing the picking process after the loosening operation in a large number of regions where the remaining number of workpieces for each region obtained after the picking process is larger; A workpiece picking method including the above steps.

6. A workpiece picking system comprising an imaging unit, a supply stage wider than the imaging range corresponding to the angle of view of the imaging unit, a supply unit for supplying workpieces onto the supply stage, a picking unit for picking up the workpieces supplied in a scattered state on the supply stage, a loosening unit for performing a loosening operation for loosening the mass of workpieces on the supply stage, and a control unit, wherein the control unit controls the imaging unit and the picking unit to perform a picking process of selecting and picking up pickable workpieces based on an image obtained by imaging the region in each of a plurality of regions obtained by dividing the supply stage based on the imaging range; controls the supply unit and the loosening unit so as to perform a loosening operation for supplying new workpieces to the supply stage to loosen the mass of workpieces or to perform the loosening operation without supplying new workpieces based on the remaining number of workpieces for each region remaining after the picking process; controls the imaging unit and the picking unit to perform the picking process after the loosening operation in the region with the largest number of remaining workpieces for each region obtained after the picking process, where the remaining number of workpieces is the largest; A workpiece picking system.

Images