ARTICLE TRANSPORT SYSTEM WITH MULTIPLE MOVING PARTS

Abstract

Article transport system (10), comprising a sensor (14) that detects the three-dimensional position of each of a plurality of articles (12); a robot (18a, 18b) provided with a plurality of movable parts (22a, 22b) that transports the articles (12) to a specific transport destination (16a, 16b); a control unit (20) that controls the robot (18a, 18b); a movement amount calculation unit (24) which, based on the three-dimensional position of each of the articles (12), calculates the movement amount of each of the movable parts (22a, 22b) when transporting each of the plurality of articles (12) by any one of the movable parts (22a, 22b); and a distribution determining unit (26) that determines a distribution pattern for transporting each of the plurality of articles (12) using each movable part (22a, 22b) among the plurality of movable parts (22a, 22b) such that the difference between the moving amounts of the movable parts (22a, 22b) becomes the smallest or less than a predetermined value.

Description

General state of the art

[0001] The present invention relates to an article transport system with multiple moving parts.

[0002] A removal device that captures a plurality of articles irregularly arranged in a container with a camera, detects the position of the individual articles by image processing of the obtained image, and performs a removal operation by a robot based on the detected positions is known (see, for example, Patent Application Laid-Open No. JP 2014-087913 A).

[0003] Furthermore, a system is known that photographs a plurality of articles transported by a conveyor with a camera, detects the position of the articles by image processing of the obtained image, and transports articles by a plurality of robots arranged downstream of the camera based on the detected positions (see, for example, International Publication No. WO 2014 / 013 607 A1).

[0004] Furthermore, a transport system configured to calculate a rotation direction and a rotation angle of each arm when taking out a workpiece using a robot having two arms, select the arm whose rotation amount becomes the smallest, and use the selected arm for taking out the workpiece is known (see, for example, Patent Application Laid-Open No. JP H10-329069 A).

[0005] Further article transport systems that use one or more robots to transport articles are known from DE 10 2018 101 375 A1, DE 10 2017 125 190 A1, EP 2 876 066 A1, EP 2 537 645 B1, EP 2 492 055 B1 and US 2012 / 0 165 972 A1.

[0006] In an application / system where multiple items are transported using a robot equipped with multiple moving parts, it is often necessary to calculate / determine which moving part will transport each item so that the transport of all items can be completed in the shortest possible time. However, in such a case, the load may be concentrated on a specific moving part, increasing the maintenance frequency of only that specific moving part. From the perspective of managing and maintaining the transportation system as a whole, it is desirable to keep the maintenance frequency of each moving part as uniform as possible. Brief description of the invention

[0007] The invention is based on the object of specifying an article transport system with a robot in which the frequency of maintenance of individual moving parts of the robot is kept as uniform as possible.

[0008] According to the invention, this object is achieved with regard to the article transport system by the subject matter of claim 1.

[0009] Specifically, the above object is achieved by an article transportation system comprising a sensor that detects the three-dimensional position of each of a plurality of articles; a robot that is provided with a plurality of moving parts and transports the articles to a predetermined transportation destination; a control unit that controls the robot; a movement amount calculation unit that calculates, based on the three-dimensional position of each of the articles, the movement amount of each of the moving parts when transporting each of the plurality of articles by any one of the moving parts; and a distribution determination unit that determines a distribution pattern for transporting each of the plurality of articles using each moving part among the plurality of moving parts such that the difference between the movement amounts of the moving parts becomes the smallest or less than a predetermined value. Simple explanation of the drawings

[0010] The objects, features and advantages of the present invention will become more apparent from the following explanation of embodiments taken in conjunction with the accompanying drawings. In these accompanying drawings is Fig. 1 is a view showing the structure of an article conveying system according to a first embodiment; is Fig. 2 is a flowchart showing the workpiece detection processing in the first embodiment; is Fig. 3 is a flowchart showing distribution and transportation processing in the first embodiment; is Fig. 4 is a flowchart showing the distribution pattern determination processing in the first embodiment; is Fig. 5 is a plan view showing the positional relationship between workpieces on a conveyor and the workpiece transport destination; is Fig. 6 is a side view showing the positional relationship between workpieces on a conveyor and the workpiece transport destination; is Fig. 7 is a view showing an example in which workpieces are stacked in ten stages; is Fig. 8 is a view showing the structure of an article conveying system according to a second embodiment; is Fig. 9 is a flowchart showing distribution and transport processing in a third embodiment; and is Fig. 10 is a flowchart showing the distribution pattern determination processing in the flowchart of Fig. 9 shows. Detailed explanation

[0011] Fig. 1 is a view showing a basic structural example of an article transport system 10 according to a first embodiment. The article transport system 10 includes a sensor 14 that detects the three-dimensional position of each of a plurality of articles (workpieces) 12; robots (here, two robots) 18a and 18b equipped with a plurality of movable parts that transport the workpieces 12 to specific transport destinations (here, pallets or the like) 16a and 16b, respectively; a controller 20 that controls the robots 18a and 18b; a movement amount calculation unit 24 that calculates, based on the three-dimensional position of each workpiece 12, the movement amount of the respective movable parts (here, robot arms 22a and 22b) of the robots 18a and 18b when each of the plurality of workpieces 12 is transported by any one of the robots 18a and 18b; and a distribution determination unit 26.which determines a distribution pattern for transporting each of the workpieces 12 using each of the robot arms 22a, 22b such that the difference between the amount of movement of the robot arm 22a and the amount of movement of the robot arm 22b becomes the smallest or less than a certain value.

[0012] The control unit 20, the movement amount calculation unit 24, and the distribution determination unit 26 are a computing device (a processor) such as a CPU or the like, which can be incorporated into a robot control device 28. Furthermore, the robot control device 28 may further include a storage unit 30 such as a memory that can store various data. Furthermore, at least some of these constituent elements may be provided in a computer (a personal computer or the like) separate from the robot control device 28.

[0013] In the first embodiment, a plurality of workpieces 12 are transported one after the other at a specific transport speed in a specific transport direction (indicated by arrow 32 in the illustrated example). A conveyor device 34, such as a belt conveyor, is provided. For the sensor 14, for example, a general-purpose 3D image sensor can be used. The sensor 14 can detect the three-dimensional position and orientation of workpieces within a specific measurement area. Specific examples of a 3D image sensor include a sensor based on the stereo vision method, the structured light method, the laser triangulation measurement method, or the time-of-flight (TOF) method.As concrete examples of a sensor 14 other than a 3D image sensor, a combination of a 2D camera and a distance sensor can be cited, wherein in this case the 2D camera measures / obtains information regarding the XY coordinates of a measurement object and the distance sensor measures / obtains the Z coordinate of the measurement object and thereby the three-dimensional position and attitude of the measurement object can be detected.

[0014] The robot 18a is, for example, a six-axis articulated robot having a hand 36a attached to the tip end of its arm 22a and capable of holding a workpiece 12. The robot 18a can grasp workpieces 12 transported by the conveyor 34 one by one based on a distribution pattern described later (one by one in the illustrated example) and transport them to a transport destination 16a. Likewise, the robot 18b is, for example, a six-axis articulated robot having a hand 36b attached to the tip end of its arm 22b and capable of holding a workpiece 12. The robot 18b can also grasp workpieces 12 transported by the conveyor 34 one by one based on a distribution pattern described later (one by one in the illustrated example) and transport them to a transport destination 16b.

[0015] The article transport system 10 according to the first embodiment includes two robots 18a and 18b, each equipped with a movable part (arm), but this is not limited to this. For example, there may be three or more robots equipped with a movable part, and as long as each robot can transport a workpiece, it is not limited to a six-axis articulated robot. Or, it is also possible that one robot actually has multiple movable parts (arms), and each movable part can independently perform an operation of holding and transporting a workpiece. In the specification of the present application, the "robot with multiple movable parts" includes any of these configurations.

[0016] The following explains the processing sequence of the article transport system 10. Here it is assumed that, as in Fig. 1, workpieces 12 are transported by the conveyor device 34 in a state stacked in two stages.

[0017] Fig. 2 is a flowchart showing an example of detection processing by the sensor 14. First, the controller 28 or the like determines whether the conveyor 34 has moved a certain distance (more specifically, whether the feed amount of the transport area (belt or the like) of the conveyor 34 has reached a certain distance from the start of detection) using an encoder 38 or the like formed on the conveyor 34 (step S1). When the conveyor 34 has moved the certain distance, the sensor 14 captures an image of a certain area on the conveyor 34 (step S2).This specific area is normally set as an area on the conveyor 34 located upstream at a specific distance from the setup position of the most upstream robot (here, the robot 18a), and the specific area in question may be set based on, for example, the characteristics of the robot or the running speed of the processing described below or the like.

[0018] In the following step S3, using a control device or an image processing device (not shown) or the like of the sensor 14, image processing of the image obtained in step S2 is performed, and the presence or absence of workpieces 12 in the specified area on the conveyor 34 and, if workpieces 12 are present in the specified area, their three-dimensional positions are detected. At this time, the posture of the workpieces can also be detected to facilitate the gripping of the workpieces by the robots. The processing of steps S1 to S3 is repeated at a specified time period. Information (data) related to the three-dimensional positions, etc., detected by the sensor 14 is sent to the control device 28 and used in the processing in step S4 discussed later.

[0019] Fig. 3 is a flowchart showing an example of processing when the robot 18a or 18b transfers a workpiece 12 using the detection result of the sensor 14. First, at step S4, it is determined whether or not there are workpieces in the specified area (which here roughly corresponds to the detection area of ​​the sensor 14) for which the three-dimensional position detection, etc., has been completed and the distribution processing described below has not been performed, and if there are such workpieces, it proceeds to step S5.

[0020] At step S5, the above-described distribution determination unit 26 determines a distribution pattern indicating which of the robots should transport the above workpieces. Details will be explained below using the flowchart of Fig. 4. Here it is assumed that the number of the pile of workpieces stacked in two stages n (in the example of Fig. 1 (a total of three, one of which is located in the upper stage and two in the lower stage), and the range of the presence of workpieces that the upstream robot 18a can grasp and transport is assumed to be Xa to Xb. Xa and Xb are coordinates in the direction along the transport direction of the conveyor 34 (the X direction).

[0021] First, in step S51, the number n of workpieces for which distribution processing is to be performed is determined from the detection data of the sensor 14. Subsequently, in step S52, the above-described distribution determination unit 26, etc., creates / determines, for each of the n workpieces 12, several (and preferably all) combinations (distribution patterns) in the case of transport by the robot 18a or 18b. Since, in the present embodiment, the number of workpieces is n and the number of moving parts (robots) is two, a maximum of 2 n Distributions of the workpieces are conceivable, but combinations in which the upstream robot 18a transports workpieces of the lower stage and the downstream robot 18b transports workpieces of the upper stage, which are even only partially located above workpieces of the lower stage, are excluded.

[0022] In the subsequent step S53, the movement amount of the movable part 22a of the robot 18a and the movement amount of the movable part 22b of the robot 18b are calculated for each of the combinations determined in step S52. A concrete example of this is explained below.

[0023] Fig. 5 and Fig. 6 are a plan view and a side view illustrating the positional relationship between workpieces 12 on the conveyor 34 and the transport destination 16a (16b), by way of example. Here, it is assumed that the hand 36a or 36b, whose position is represented as a representative point (for example, the front end point of the workpiece) of the robot 18a or 18b, moves from its initial position P0 via a workpiece approach position P1 directly above the workpiece 12 constituting the transport object to a workpiece grasping position P2, and grasps the workpiece 12, and moves via a retracted position P3 (which roughly coincides with P1 here) and a transport approach position P4 directly above the transport destination 16a or 16b to the transport position P5 where the workpiece 12 is placed at the transport destination 16a or 16b.

[0024] Now, if the longest moving distance from P3 to P4 among P0 to P5 is taken as an example, the moving distance L1 of the upper-stage workpiece and the moving distance L2 of the lower-stage workpiece can be expressed by the following formulas (1) and (2), respectively. L1=√((X−X0)2+(Y−Y0)2+H2) L1=√((X−X0)2+(Y−Y0)2)

[0025] As described above, the upstream robot 18a can grasp and transport workpieces in the X-coordinate range from Xa to Xb, but it is assumed here that, in the case of transporting multiple workpieces, the robot 18a grasps and transports the first workpiece when its X-coordinate is Xa and grasps and transports the last workpiece when its X-coordinate is Xb. Further, when three or more workpieces are transported by the robot 18a and their number is assumed to be k, the workpieces except the first and last workpieces can be grasped and transported by the robot 18a when their X-coordinate has reached the value expressed by the following formula (3). In the formula (3), i = 1, 2, ... k-2. X=Xa+(Xb−Xa) / (k−1))×i

[0026] From the above formula (3) etc., the moving distance of the movable part (here, the hand attached to the tip end of the arm) when transporting each workpiece, or a predicted value for the workpiece transport distance, can be obtained as the moving amount of the movable part. This also applies to the robot 18b.

[0027] Next, at step S54, from all the distribution patterns obtained at step S53, the distribution pattern in which the difference between the movement amount of the movable part of the robot 18a and the movement amount of the movable part of the robot 18b becomes the smallest or less than a certain value is selected / determined as the distribution pattern in the actual transfer of the workpieces. When the same movable part transfers multiple workpieces consecutively, the movement amount expresses the total value of the movement amounts when each workpiece is transferred. In this way, a distribution pattern that equalizes the load on each robot when transferring n workpieces can be automatically determined. The certain value can be empirically determined, for example, taking into account the maintenance frequency of the movable parts such as the robot arms or the like.

[0028] With further reference to Fig. 3, in step S6, it is detected whether or not there are workpieces in the area detected by the sensor 14 for which the determination of which robot to transport them has been completed but the actual transport has not taken place. If such a workpiece is not present, the process returns to step S4. If such a workpiece is present, the workpiece is transported according to the determined distribution pattern (step S7). The processing of steps S4 to S7 is executed when the sensor 14 has detected workpieces to be transported again.

[0029] In the above-described embodiment, a case was explained where workpieces are stacked in two stages, but the same processing can also be applied when workpieces are stacked in three or more stages. For example, as in Fig. 7, consider a case where workpieces 12 are stacked in ten stages, the height H of each workpiece is 100 mm, and the horizontal distance from the arrangement position of the workpieces on the conveyor to the workpiece destination (Y - Y0) is 500 mm.

[0030] In order to equalize the load on the individual robots, it is usually first considered to make the number of workpieces that the individual robots transport the same, but if in the example of Fig. 7, assuming that the two robots each transport five workpieces (concretely, the robot 18a transports the upper five workpieces and the robot 18b transports the lower five workpieces), the transport distance La of the movable part of the robot 18a and the transport distance Lb of the movable part of the robot 18b are respectively given by the following formulas (4) and (5) (unit: mm), and it is recognized that the load of the robot 18a becomes much larger than that of the robot 18b. La=1030+943+860+781+707=4321 Lb:640+583+539+510+500=2772

[0031] Now, when the present embodiment is applied, a distribution pattern is automatically determined in which the robot 18a transports the upper four workpieces and the robot 18b transports the lower six workpieces, the transport distance La' of the movable part of the robot 18a and the transport distance Lb' of the movable part of the robot 18b are respectively given by the following formulas (6) and (7) (unit: mm), and it is recognized that the movement amounts of the two robots are equalized. La'=1030+943+860+781=3614 Lb':707+640+583+539+510+500=3479

[0032] Therefore, in the present embodiment, the load on the robots when transporting workpieces can be equalized even in a state where multiple workpieces are stacked. Thus, by using the three-dimensional position (especially the height information) of the workpieces, a distribution pattern for the workpieces can be determined, thereby making the maintenance frequency approximately equal among the robots, and also facilitating the maintenance and management of the transportation system as a whole.When a plurality of workpieces are transported by a conveyor or the like at a certain speed as in the present embodiment, it is necessary to complete the transport of all the workpieces to a transport destination within a certain time, and since the movement amount of the robots is equalized in the present embodiment, the time required for the transport of each robot can also be equalized.

[0033] In the example described above, the movement distance of each robot's movable part from P0 to P5 was calculated as the movement amount. However, in terms of the load on the robot, the load is greater when the robot grasped a workpiece than when it did not grasp a workpiece. For example, the robot's movable part can be calculated only for the distance P2 to P5 where the robot grasped a workpiece, and the distance P2 to P2 (i.e., the workpiece transport distance) can be used as the movement amount of the movable part. Alternatively, it is possible to calculate the total by assigning different weights to the distance P2 to P5 where the robot grasped a workpiece and the distance P0 to P2 where it did not grasp a workpiece (specifically, the weight of the latter is lower), and use the resulting total value as the movement amount of each movable part.

[0034] In the example described above, the movement distance of the moving part (the workpiece) was used as the movement amount of the robot's moving part. However, from the perspective of robot maintenance frequency, it may be more appropriate to use the cumulative rotation angle of at least one axis driving the moving part as the movement amount of the moving part. A specific example is explained below.

[0035] If the rotational angular position of an axis (here assumed to be axis J1) driving the hand changes from (-35° → +120° → +10°) on the above-mentioned hand movement distance from P3 to P4, the range of motion (the cumulative rotational angular range) of axis J1 reaches 265° (= 155° + 110°). It is assumed that the rotational angular position changes monotonically (monotonically increases or monotonically decreases) between -35° and +120° and between +120° and +10°.

[0036] If it is assumed that the number of changes of the rotation angle position from an increase to a decrease or from a decrease to an increase during the change of the rotation angle position of each axis of the robot from X 0 to X n and the angles when changing from increase to decrease or from decrease to increase are X 1 , X 2 , ... X n Assuming that k = 1, 2, ..., n, the cumulative rotation angle (movement amount) D of each axis can generally be represented by the following formula (8). In formula (8), k = 1, 2, ..., n. The rotation angle position of each axis can be obtained from the detection value of an encoder or the like (not shown) formed on each axis, or from the command value included in the operation command sent from the robot control device to each robot. D=∑(|Xk−Xk−1|)

[0037] By calculating the movement amounts (cumulative rotation angles) of the axes of each robot for each distribution pattern using formula (8), the optimal distribution pattern can be selected / determined. For the axis movement amount, for each robot, only the movement amount of a specific axis (for example, axis J1) among the axes that drive the moving part can be used, or the sum of the movement amounts of all axes (for example, axes J1 to J6) related to driving the moving part can be used. If there is a large difference in maintenance effort and cost between axes J1 to J6, the sum can be obtained after assigning a certain weight to the movement amounts of each axis, and this sum can be used as the movement amount in determining the optimal distribution pattern.This use of the movement amount of each axis can also be applied to the second embodiment and the third embodiment described below.

[0038] Fig. 8 is a view showing a basic structural example of an article conveying system 10' according to a second embodiment. The second embodiment differs from the first embodiment only in the number of control units (control devices), while other structural elements and processing are the same as those in the first embodiment. While in the first embodiment, a plurality of robots are actually controlled by one control device, the article conveying system 10' includes a control unit that controls the first robot 18a (a robot control device 28a) and a control unit that controls the second robot 18b (a robot control device 28b), and the robot control devices 28a and 28b are communicatively connected through the Ethernet (registered trademark) 40 or the like.

[0039] In the second embodiment, the controller 28a controlling the upstream robot 18a performs the processing of the controller 28 in the first embodiment and determines the optimal distribution pattern. Then, based on the determined distribution pattern, the controller 28a sends a command to the robot 18a instructing the robot 18a to pick up the workpieces it should transport and transport them to the pallet 16a, and sends information regarding the workpieces that the robot 18a should not transport (that is, that the robot 18b should transport) to the controller 28b of the robot 18b. Therefore, it is sufficient for the controller 28b to control the robot 18b based on the information from the controller 28a.

[0040] Since the number of control units (control devices) in the second embodiment is larger than in the first embodiment, the entire article conveying system is rather disadvantageous from a cost perspective. However, in general, there is an upper limit to the number of robots that can be controlled by a single control unit, or it may be difficult for a single control device to perform the calculation processing in the present disclosure due to the characteristics of its CPU. In such a case, it is advantageous to provide a control unit for each robot as in the second embodiment.

[0041] The third embodiment is similar in structure to the first or second embodiment in the article transport system, but the processing for determining the optimal distribution pattern is different from the first or second embodiment. The following will be explained with reference to the flowchart of Fig. 9 explains a concrete example.

[0042] The steps S14 to S17 in the flowchart of Fig. 9 can be assigned to steps S4 to S3 of the flow chart of Fig. 3. The difference to the flow chart of Fig. 3 is that in Fig. 9, after step S17, a step S18 is included in which the actual movement amount of each robot (the movement distance of the movable part or the movement amount of each axis or the like) is stored in the storage unit 30 (see Fig. 1) is stored.

[0043] Next, referring to the flowchart of Fig. 10 Details regarding step S15, in which the ideal distribution pattern is determined, are explained. Steps S151 to S153 can be corresponding to steps S51 to S53 of the flowchart of Fig. 4, but this can be done at step S53 of Fig. 4 calculated movement range of each robot can also be called the prediction value for the movement range of each robot.

[0044] Now, in the subsequent step S154, the actual value of the movement amount of each robot stored in step S18 is added to the prediction value calculated in step S153.

[0045] The third embodiment can be ideally applied to a case where, as exemplified in Fig. 1, there are multiple piles of n workpieces. That is, the respective movement amounts of the robots 18a and 18b after transporting a pile of n workpieces are stored as actual values ​​(step S18), and predicted values ​​for the movement amounts of each robot when transporting the next pile of n workpieces are calculated (steps S151 to S153). This calculation may be the same as that in the first embodiment.

[0046] Then, for each robot, the prediction value is added to the actual value (S154), and the distribution pattern in which the difference between the sums becomes smallest or less than a certain value is selected / determined as the ideal solution (step S155), whereby a distribution pattern in which the load of each robot has been further equalized compared to using only the prediction value can be obtained.

[0047] If, as an application example, the third embodiment is applied, for example, to the case of transporting several groups of workpieces, as in Fig. 7 shown in ten stages stacked workpieces constitute a group, is applied by a conveyor, the following results are obtained.

[0048] As described above, in the case of a workpiece group, a pattern in which the upper workpieces are transported by the robot 18a and the lower six workpieces are transported by the robot 18b is selected as the ideal distribution pattern. However, as can be seen from formulas (6) and (7), the moving distances of the two robots are not completely equal, but there is a certain difference (here, 135 mm). Therefore, when this distribution pattern is repeated, the cumulative moving distance of the two robots gradually increases.

[0049] Since the movement amount of each robot is taken into account in the third embodiment, a pattern in which the upper three workpieces are transported by the robot 18a and the lower seven workpieces is selected as the ideal distribution pattern for some of the multiple workpiece groups. Thus, in the third embodiment, the movement distance (load) of each robot can be adjusted with even higher accuracy.

[0050] The above-described embodiments can be combined as appropriate. For example, the calculation processing of the third embodiment can be performed in the configuration of the second embodiment, the workpieces to be transported by the upstream robot 18a can be determined based on the sum of the actual value and the predicted value of the movement amount of the movable part of the robot 18a, and the information regarding the workpieces not transported by the robot 18a can be sent from the robot control device 28a to the robot control device 28b.

[0051] In each of the above-described embodiments, the movement distance of the movable part of the robot (the transport distance of the workpiece) is preferably set so as to avoid collisions with other workpieces or surrounding objects, etc. Regarding the means or method for determining the transport distance so as to avoid collisions, a well-known technique can be applied, and a detailed explanation is omitted here.

[0052] Since the movement amounts of the individual moving parts are equalized according to the present disclosure, the load on the individual moving parts is also dispersed / equalized. Therefore, the periods or intervals for maintenance of the moving parts can also be equalized, and the maintenance / management of the transportation system as a whole becomes easy.

Claims

[1] Article transport system (10), comprising a sensor (14) that detects the three-dimensional position of each of a plurality of articles (12); a robot (18a, 18b) provided with a plurality of movable parts (22a, 22b) that transports the articles (12) to a specific transport destination (16a, 16b); a control unit (20) that controls the robot (18a, 18b); a movement amount calculation unit (24) which, based on the three-dimensional position of each of the articles (12), calculates the movement amount of each of the movable parts (22a, 22b) when transporting each of the plurality of articles (12) by any one of the movable parts (22a, 22b); and a distribution determining unit (26) that determines a distribution pattern for transporting each of the plurality of articles (12) using each movable part (22a, 22b) among the plurality of movable parts (22a, 22b) such that the difference between the moving amounts of the movable parts (22a, 22b) becomes the smallest or less than a predetermined value. [2] The article conveying system (10) according to claim 1, wherein the movement amount calculation unit (24) calculates the cumulative rotation angle of at least one axis driving the movable part (22a, 22b) as the movement amount of the movable part (22a, 22b). [3] The article transport system (10) according to claim 1, wherein the movement amount calculation unit (24) calculates the transport distance of the article (12) transported by the movable part (22a, 22b) as the movement amount of the movable part (22a, 22b). [4] The article conveying system (10) according to any one of claims 1 to 3, further comprising a storage unit (30) that stores the actual value of the movement amount of each of the plurality of movable parts (22a, 22b), wherein the distribution determining unit (26) determines the distribution pattern using a value for which the movement amount calculated by the movement amount calculating unit (24) is added to the actual value stored for each of the plurality of movable parts (22a, 22b) in the storage unit (30). [5] Article transport system (10) according to one of claims 1 to 4, further comprising a conveyor device (34) which transports a plurality of articles (12) at a specific transport speed in a specific transport direction. [6] Article transport system (10) according to one of claims 1 to 5, comprising a plurality of control units (28a, 28b) each controlling the plurality of movable parts (22a, 22b).

Images