Production system

Abstract

A production system including a conveying device that conveys an article, a robot that performs work on the article conveyed by the conveying device, and a moving device that moves the robot, the production system including a sensor that acquires position information of the article conveyed by the conveying device, a calculation section that calculates a velocity vector of the article conveyed by the conveying device based on the position information acquired by the sensor, and a control section that, when a moving direction of the article conveyed by the conveying device and a moving direction of the robot moved by the moving device are different, controls a velocity vector of the robot moved by the moving device and a velocity vector of a position of an end effector of the robot so that a sum of the velocity vector of the robot moved by the moving device and the velocity vector of the position of the end effector of the robot coincides with the velocity vector of the article conveyed by the conveying device.

Description

Technical Field

[0001] This invention relates to production systems. Background Technology

[0002] A production system is known in which a robot performs operations on items conveyed by a conveyor. The production system comprises: a conveyor for conveying items; a robot for performing operations on the items conveyed by the conveyor; and a moving device for moving the robot. In the production system, it is important to maintain the proper positional relationship of the robot to perform operations on the items.

[0003] For example, in a following control method that enables a robot with a travel axis, which has a robot body and a travel axis for moving the robot body in a predetermined direction, to follow a continuous line, a following control method for a robot with a travel axis is known as follows: the travel speed of the line is divided into units of time, the average speed of each unit of time is calculated, the travel axis of the robot with the travel axis is controlled so that it follows the line at the average speed of each unit of time, and the following deviation between the travel axis and the line is used as the robot deviation in the direction of the travel axis to control the joint axis of the robot body for correction (for example, see Patent Document 1).

[0004] For example, a known operating system includes: a conveying device for conveying items; a movable platform; an operating unit fixed to the platform for operating on the items conveyed by the conveying device; a vision sensor fixed to the platform for sequentially acquiring visual information of the items conveyed by the conveying device or marks formed on the conveying device; a detection unit for processing the visual information acquired by the vision sensor and sequentially detecting at least the position of the items or the marks; a calculation unit for calculating the conveying speed of the conveying device based on the positions of the items or the marks detected sequentially by the detection unit; and a drive control unit for driving the operating unit using the conveying speed (for example, see Patent Document 2).

[0005] For example, a production line control device is known, comprising: a workpiece conveying unit for conveying workpieces; a robot for performing a predetermined operation on the workpieces conveyed by the workpiece conveying unit; and a robot movement drive unit capable of moving the robot along a workpiece conveying path. The production line control device further comprises: a workpiece position detection unit for detecting the conveying direction position of the workpieces conveyed by the workpiece conveying unit; a robot position detection unit for detecting the position of the robot driven by the robot movement drive unit in the workpiece conveying direction; a robot control unit for controlling the robot; a synchronization control unit for controlling the robot movement drive unit so that the robot synchronously follows the conveyed workpieces; and a coordination control unit for coordinating the control of the robot control unit with the control of the synchronization control unit using the workpiece position detected by the workpiece position detection unit and the robot position detected by the robot position detection unit (for example, see Patent Document 3).

[0006] Existing technical documents

[0007] Patent documents

[0008] Patent Document 1: Japanese Patent Publication No. 07-060327

[0009] Patent Document 2: Japanese Patent Application Publication No. 2019-072792

[0010] Patent Document 3: Japanese Patent Application Publication No. 08-072764 Summary of the Invention

[0011] The problem that the invention aims to solve

[0012] In a production system, when the direction of movement of an item transported by a conveyor is the same as the direction of movement of a robot transported by a mobile device, if an encoder or similar device is used to calculate the speed of the conveyor, and the robot is moved at the same speed as the conveyor, thus allowing the robot to follow the item, the positional relationship for the robot to perform appropriate operations on the item can be maintained. However, sometimes the direction of movement of an item transported by a conveyor differs from the direction of movement of the robot transported by the mobile device. For example, due to various reasons such as the motion accuracy of the conveyor and / or the mobile device, and vibration, the direction of movement of the item and / or the robot may deviate from the ideal direction, causing changes in the relative distance between the robot and the item. Additionally, for example, sometimes the direction of movement of an item transported by a conveyor is not a straight line but a curve, or the item is transported in an inclined direction relative to the horizontal plane. In such cases, when the direction of movement of an item transported by a conveyor differs from the direction of movement of the robot transported by the mobile device, control based solely on the conveyor speed determined by an encoder cannot enable the robot to follow the item. Therefore, it is desirable to develop a production system that can maintain the proper positional relationship for the robot to perform operations on the items, even when the direction of movement of the items transported by the conveyor is different from the direction of movement of the robot moved by the mobile device.

[0013] Methods for solving problems

[0014] According to one aspect of this disclosure, a production system includes: a conveying device for conveying articles; a robot for performing operations on the articles conveyed by the conveying device; and a moving device for moving the robot. The production system further includes: a sensor for acquiring position information of the articles conveyed by the conveying device; a computing unit for calculating a velocity vector of the articles conveyed by the conveying device based on the position information acquired by the sensor; and a control unit for controlling the velocity vector of the robot moving via the moving device and the velocity vector of the position of the robot's end effector when the direction of movement of the articles conveyed by the conveying device differs from the direction of movement of the robot moving via the moving device, such that the sum of the velocity vector of the robot moving via the moving device and the velocity vector of the position of the robot's end effector is consistent with the velocity vector of the articles conveyed by the conveying device.

[0015] Invention Effects

[0016] According to one aspect of this disclosure, a production system can be implemented that maintains the positional relationship in which the robot can properly perform operations on the items, even when the direction of movement of the items conveyed by the conveying device is different from the direction of movement of the robot moving by the moving device. Attached Figure Description

[0017] Figure 1 This is a perspective view illustrating a production system according to one embodiment of the present disclosure.

[0018] Figure 2 This describes the relationship between the velocity vector of an article transported by a conveying device, the velocity vector of a robot, and the velocity vector of the position of the robot's end effector in a production system according to an embodiment of this disclosure.

[0019] Figure 3 This is a flowchart illustrating the operation flow of a production system according to one embodiment of the present disclosure. Detailed Implementation

[0020] The production system will now be described with reference to the accompanying drawings. The scale of these drawings has been appropriately altered for ease of understanding. The embodiments shown in the drawings are one example for implementation and are not limited to those illustrated. Furthermore, in the following description, "velocity" is a vector representing the amount of displacement of an object per unit time and its direction. In this specification, "velocity" is referred to as "velocity vector" for more precise representation of a vector. Additionally, "speed" is a scalar quantity representing the magnitude of velocity.

[0021] Figure 1 This is a perspective view illustrating a production system according to one embodiment of the present disclosure.

[0022] Production system 1 includes: a conveying device 11 that conveys items 41; a robot 12 that performs operations on the items 41 conveyed by the conveying device 11; and a moving device 13 that moves the robot 12. Here, as an example, production system 1 that performs operations such as assembling parts 42 from items 41 conveyed by the conveying device 11 by the robot 12 will be described.

[0023] In production system 1, a reference coordinate system (world coordinate system) is established that remains stationary relative to changes in the position and posture of robot 12. In this reference coordinate system, the origin is fixed, and the orientation of the coordinate axes is also fixed. The reference coordinate system has mutually orthogonal X-axis, Y-axis, and Z-axis as coordinate axes. Additionally, the W-axis is defined as the coordinate axis around the X-axis. The P-axis is defined as the coordinate axis around the Y-axis. The R-axis is defined as the coordinate axis around the Z-axis.

[0024] Furthermore, a tool coordinate system is established in production system 1, which has an origin set at any position of the end effector (working tool) 31 of robot 12. The position and orientation of the tool coordinate system change together with the end effector 31. The origin of the tool coordinate system is set at the tool tip point of the end effector 31. The position of the end effector 31 of robot 12 corresponds to the position of the tool tip point in the reference coordinate system (the position of the origin of the tool coordinate system). In addition, the orientation of the end effector 31 of robot 12 corresponds to the orientation of the tool coordinate system relative to the reference coordinate system.

[0025] The conveying device 11, which transports the article 41, can be any type of conveying device. Furthermore, the conveying direction (movement direction) of the conveying device 11 for transporting the article 41 can be any direction in the X-axis and Y-axis directions on the horizontal plane, or any direction in the Y-axis direction perpendicular to the horizontal plane. Figure 1 In this example, an AGV (Automated Guided Vehicle) is used as the conveying device 11. For example, the AGV as the conveying device 11 can move in any direction in the X-axis and / or Y-axis directions on a horizontal plane. Furthermore, the AGV as the conveying device 11 can also move on a slope with any angle of inclination relative to the horizontal plane, in which case the AGV's direction of movement is the X-axis, Y-axis, and / or Z-axis. Moreover, the conveying device 11 is not limited to the AGV shown here; for example, a belt conveyor, a conveyor with a travel axle that travels on a guide track, a magnetic levitation conveyor, and an electromagnetic levitation conveyor can be used.

[0026] The moving device 13, used to move the robot 12 (its main body), can be any type of moving device. The moving device 13 causes the robot 12 to move back and forth in one direction on a horizontal plane. Figure 1 In this example, the moving device 13 causes the main body of the robot 12 to reciprocate along the positive (+) and negative (-) directions of the X-axis. For example, the moving device 13 is a moving device with a travel axle that uses a motor (not shown) as a drive source to move the robot 12 on a guide track, supporting a support platform. Furthermore, the moving device 13 is not limited to this type; any moving device that causes the robot 12 to reciprocate in one direction on a horizontal plane can be used. For example, the moving device 13 can be a belt conveyor, an AGV, a magnetic levitation conveyor, or an electromagnetic levitation conveyor.

[0027] Robot 12 performs arbitrary operations on the item 41 conveyed by conveyor 11. The end effector 31 installed on robot 12 is an arbitrary work tool corresponding to the operation performed by robot 12. Figure 1In this example, the end effector 31 is a robotic arm that grasps or releases the component 42. The robotic arm may be an adsorption plate that grasps the surface of the component 42 by suction. Furthermore, the end effector 31 installed on the robot 12 is not limited to this method; in a production system performing welding operations, it may be a welding tool, and in a production system performing painting operations, it may be a tool for applying paint to the surface of an item.

[0028] exist Figure 1 In the example shown, robot 12 assembles component 42 onto article 41 by engaging parts 42A and 42B of component 42, which are grasped by a robotic arm acting as an end effector 31, with parts 41A and 41B of article 41, respectively. For example, article 41 is the body of a car, and component 42 is a car door or tire.

[0029] In order to enable the end effector 31 of the robot 12 to follow the movement of the items conveyed by the conveying device 11, a production system 1 according to one embodiment of the present disclosure includes a sensor 21, a computing unit 22 and a control unit 23.

[0030] Sensor 21 acquires the position information of the item 41 conveyed by the conveyor 11. Sensor 21 only needs to be able to obtain the positional relationship between the item 41 and the robot 12. In the illustrated example, sensor 21 is configured on the main body of the robot 12 to sense the position of the item 41. Alternatively, sensor 21 can also be configured above the robot 12 and the item 41 (e.g., on the ceiling of the room housing the production system 1), so that it can sense both the robot 12 and the item 41.

[0031] Methods for obtaining location information of item 41 by sensor 21 include stereo camera method and pulse radar method.

[0032] The stereo camera-type sensor 21 includes: two two-dimensional cameras that capture two-dimensional images; and a processing unit that obtains the position information of the object 41 through image processing based on the parallax of the two images captured by the two two-dimensional cameras. As an example of a two-dimensional camera, any camera equipped with an imaging element such as a CCD (Charge-Coupled Device) sensor or a CMOS (Complementary Metal-Oxide Semiconductor) sensor can be used. Alternatively, the sensor 21 may also include a projector that projects patterned light, such as stripes, onto the object 41, and the two-dimensional cameras capture the projected pattern on the object 41, based on which the position information of the object 41 is obtained.

[0033] The pulse radar sensor 21 includes: a transmitter that transmits radio waves; a receiver that receives reflected waves from the article 41; and a processing unit that obtains the position information of the article 41 based on the relationship between the radio waves transmitted by the transmitter and the reflected waves received by the receiver.

[0034] Furthermore, when the conveying device 11 is composed of a conveying device (such as an AGV) having a support platform that moves together with the item 41, the position information of the item 41 corresponds one-to-one with the position information of the support platform of the conveying device 11. Therefore, in this case, the sensor 21 can also obtain the position information of the support platform of the conveying device 11, and obtain the position information of the item 41 based on the position information of the support platform.

[0035] The position information of the item 41 transported by the conveying device 11 is periodically acquired by the sensor 21 (e.g., at a period of several hundred milliseconds) and sent to the computing unit 22.

[0036] The calculation unit 22 calculates the velocity vector of the item 41 conveyed by the conveying device 11 based on the position information periodically acquired by the sensor 21. The velocity vector of the item 41 includes a "rate" representing the amount of displacement of the item 41 per unit time and a "direction of movement" of the item 41 moving at that rate.

[0037] The computing unit 22 is composed of an arithmetic processing device (processor). Examples of arithmetic processing devices include ICs, LSIs, CPUs, MPUs, and DSPs. The computing unit 22, composed of an arithmetic processing device, is a functional module implemented, for example, by a computer program running on the processor. For example, when the computing unit 22 is constructed in the form of a computer program, the functions of the computing unit 22 can be realized by causing the arithmetic processing device to operate according to the computer program. The computer program for performing the processing of the computing unit 22 can be provided in the form of a computer-readable recording medium such as a semiconductor memory, magnetic recording medium, or optical recording medium. Alternatively, the computing unit 22 can be implemented as a personal computer, wherein the personal computer has a semiconductor integrated circuit on which a computer program for implementing the function is written.

[0038] In addition, a first control device 14 and a second control device 15 are provided in the production system 1.

[0039] The second control device 15 has the function of controlling the operation of the conveying device 11. That is, the second control device 15 controls the speed vector of the conveying device 11 according to a predetermined operation program. The speed vector includes a "rate" representing the amount of displacement of an object per unit time and a "direction of movement" of the object moving at that rate. Therefore, the control of the speed vector includes both "rate control" and "direction control". For example, when the conveying device 11 is composed of an AGV, a magnetic levitation conveyor, or an electromagnetic levitation conveyor, the second control device 15 controls the rate at which the conveying device 11 transports the item 41 and its direction of movement. When the conveying device 11 is composed of a belt conveyor or a conveyor with a travel axle that travels on a guide track, since the direction of movement of the item 41 transported by the conveying device 11 is predetermined, the second control device 15 controls the conveying rate of the item 41 transported by the conveying device 11.

[0040] The first control device 14 has the functions of controlling the operation of the robot 12 and controlling the movement of the moving device 13. Within the first control device 14, in addition to a control unit (not shown) for controlling the movement of the end effector 31 required for the operation of the item 41, a control unit 23 is also provided. This control unit 23 controls the movement of the robot 12 by the moving device 13 and the position movement of the end effector 31 of the robot 12. The control unit 23 controls the velocity vector of the robot 12 (its main body) and the velocity vector of the end effector 31 of the robot 12 based on the velocity vector of the item 41 calculated by the calculation unit 22. More specifically, the control unit 23 controls the velocity vector of the robot 12 moving via the moving device 13 and the velocity vector of the end effector 31 of the robot 12, such that the sum of the velocity vector of the robot 12 moving via the moving device 13 and the velocity vector of the end effector 31 of the robot 12 is consistent with the velocity vector of the item 41 being transported by the conveying device 11. The velocity vector contains a "rate" representing the amount of displacement of the object per unit time and a "direction of movement" of the object moving at that rate. Therefore, the control of the velocity vector includes both "rate control" and "direction control". The details of the control unit 23's control processing for movement and the movement of the position of the end effector 31 of the robot 12 will be described later.

[0041] Both the first control device 14 and the second control device 15 are equipped with a processing unit (processor). Examples of processing units include ICs, LSIs, CPUs, MPUs, and DSPs. The control unit 23, comprised of the processing unit within the first control device 14, is a functional module implemented, for example, by a computer program running on the processor. For instance, when the control unit 23 is constructed as a computer program, its functions can be realized by causing the processing unit to operate according to the computer program. The computer program for executing the processing of the control unit 23 can be provided in the form of a computer-readable recording medium such as a semiconductor memory, magnetic recording medium, or optical recording medium. Alternatively, the control unit 23 can be implemented as a semiconductor integrated circuit in which a computer program for implementing the function is written.

[0042] The first control device 14 and the second control device 15 can be configured as a single control device. Alternatively, the calculation unit 22 can be included within the single control device. Furthermore, the calculation unit 22 can also be configured to be included within either the first control device 14 or the second control device 15.

[0043] Next, the details of the control processing of the control unit 23 for movement and the movement of the position of the end effector 31 of the robot 12 will be explained.

[0044] Figure 2 This describes the relationship between the velocity vector of an article transported by a conveying device, the velocity vector of a robot, and the velocity vector of the position of the robot's end effector in a production system according to an embodiment of this disclosure. Figure 2 In the figure, reference numeral 100 indicates the velocity vector of the item 41 calculated by the calculation unit 22. In addition, reference numeral 200 indicates the velocity vector of the robot 12 (the main body) controlled by the control unit 23, and reference numeral 300 indicates the velocity vector of the position of the end effector 31 of the robot 12 controlled by the control unit 23.

[0045] The main body of robot 12 moves back and forth in the positive (+) and negative (-) directions of the X-axis through the action of the moving device 13.

[0046] On the other hand, depending on the structure of production system 1, sometimes the item 41 conveyed by conveyor 11 does not move parallel to the movement direction of the robot 12's main body, but moves in a direction away from or closer to the robot 12's main body (Y-axis direction and / or Z-axis direction). Furthermore, there are production systems 1 with structures where the movement direction of the item 41 conveyed by conveyor 11 is not a straight line but a curve, or the item 41 is conveyed in a direction inclined relative to the horizontal plane. Additionally, even in production systems 1 designed so that the movement direction of the item 41 conveyed by conveyor 11 is parallel to the movement direction of the robot 12's main body, due to various reasons such as the motion accuracy of conveyor 11 and / or the movement of moving device 13 and vibration, sometimes the movement direction of the item 41 and / or the movement direction of the robot 12 (the main body) deviates from its original direction, and the relative distance between the robot 12 (the main body) and the item 41 changes.

[0047] Thus, in production system 1, a state occurs where the direction of movement of the item 41 conveyed by the conveyor 11 is different from the direction of movement of the robot 12 (the main body) moving via the moving device 13. Therefore, in one embodiment of this disclosure, the control unit 23 controls the velocity vector 200 of the robot 12 and the velocity vector 300 of the end effector 31 of the robot 12 based on the velocity vector 100 of the item 41 calculated by the calculation unit 22. More specifically, when the direction of movement of the item 41 conveyed by the conveyor 11 is different from the direction of movement of the robot 12 (the main body) moving via the moving device 13, the control unit 23 controls the velocity vector of the robot 12 (the main body) moving via the moving device 13 and the velocity vector of the position of the end effector 31 of the robot 12, such that the sum of the velocity vector 200 of the robot 12 (the main body) moving via the moving device 13 and the velocity vector 300 of the position of the end effector 31 of the robot 12 is consistent with the velocity vector of the item 41 conveyed by the conveyor 11. Therefore, even if the direction of movement of the item 41 conveyed by the conveying device 11 in the production system 1 is different from the direction of movement of the robot 12 (the main body) moving by the moving device 13, the robot 12 can maintain the positional relationship in which it can properly perform operations on the item.

[0048] The moving device 13 only needs to move the main body of the robot 12 back and forth in the positive (+) and negative (-) directions of the X-axis. Therefore, the velocity vector of the robot 12 controlled by the control unit 23 ideally only has an X-axis component. However, in reality, due to the influence of the motion accuracy of the moving device 13 and vibration, the main body of the robot 12 controlled by the control unit 23 undergoes slight changes in the Y-axis and / or Z-axis directions. Since the position information of the item 41 obtained by the sensor 21 represents the position of the item 41 relative to the main body of the robot 12, the velocity vector of the item 41 calculated by the calculation unit 22 based on the position information of the item 41 also includes the Y-axis component and / or Z-axis component caused by the motion accuracy and vibration of the moving device 13. Therefore, by controlling the velocity vector 200 of the robot 12 and the velocity vector 300 of the end effector 31 of the robot 12 based on the velocity vector 100 of the item 41 calculated by the calculation unit 22, the control unit 23 can also cope with the changes in the Y-axis direction and / or Z-axis direction of the main body of the robot 12 caused by the motion accuracy of the moving device 13 and vibration.

[0049] Furthermore, the velocity vector of the item 41 conveyed by the conveyor 11 can be determined based on the design data and control data of the production system 1. However, as mentioned above, due to various reasons such as the motion accuracy and vibration of the conveyor 11 and / or the moving device 13, the "actual" velocity vector of the item 41 is likely to deviate from the "ideal" velocity vector of the item 41 determined based on the design of the production system 1. In one embodiment of this disclosure, the velocity vector of the item 41 calculated based on the position information of the item 41 obtained by the sensor 21, that is, the velocity vector 200 of the robot 12 and the velocity vector 300 of the end effector 31 of the robot 12 are controlled based on the "actual" velocity vector of the item 41. Therefore, compared with the case where the velocity vector of the item 41 is determined based on the design data and control data of the production system 1, the positional relationship in which the robot 12 can properly perform operations on the item can be maintained more accurately and reliably.

[0050] Figure 3 This is a flowchart illustrating the operation flow of a production system according to one embodiment of the present disclosure. Here, as an example, a production system 1 in which the robot 12 assembles parts 42 onto articles 41 transported by the conveyor 11 will be described.

[0051] The robot work area, in which the robot 12 can perform operations on the items 41 conveyed by the conveyor 11, is defined by the conveyable range of the conveyor 11 for transporting the items 41, the movable range of the robot 12's arm, and the movable range of the robot 12's main body moved by the moving device 13. For example, in a production system 1 where multiple items 41 flow sequentially into the robot work area via the conveyor 11, the robot 12 begins following and performing operations on the item 41 as it enters the robot work area, and completes its operations on the item 41 until it exits the robot work area. In step S101, the control unit 23 controls the moving device 13 so that the robot 12's main body waits at the start of the operation position until the item 41 enters the robot work area.

[0052] When item 41 enters the robot's working area, in step S102, sensor 21 obtains the position information of item 41 conveyed by conveying device 11.

[0053] In step S103, the calculation unit 22 calculates the velocity vector of the item 41 conveyed by the conveying device 11 based on the position information obtained by the sensor 21, and sends it to the control unit 23 in the first control device 14.

[0054] In step S104, the control unit 23 controls the velocity vector of the robot 12 moving through the moving device 13 and the velocity vector of the position of the end effector 31 of the robot 12, so that the sum of the velocity vector of the robot 12 moving through the moving device 13 and the velocity vector of the position of the end effector 31 of the robot 12 is consistent with the velocity vector of the item 41 conveyed by the conveying device 11.

[0055] In step S105, the first control device 14 determines whether the robot 12 has completed its operation on the item 41.

[0056] If, in step S105, the first control device 14 determines that the robot 12 has not completed the assembly operation of the item 41, it returns to step S102. Steps S102 to S105 are repeatedly executed at a predetermined period (e.g., a period of several hundred milliseconds). During the repeated execution of steps S102 to S105, the first control device 14 controls the robot 12 to perform the assembly operation of component 42 onto the item 41. Additionally, a two-dimensional camera for the assembly operation is positioned near the end effector 31. The item 41 is photographed at a high frequency (e.g., several milliseconds) using the two-dimensional camera, and the operation required to assemble component 42 onto the item 41 is performed while using pattern matching processing based on the photographed images to precisely control the movement of the end effector 31 on the item 41.

[0057] In step S105, if the first control device 14 determines that the robot 12 has completed the assembly operation of the item 41, the processing of the item 41 ends. Afterwards, the control unit 23 controls the main body of the robot 12 to move to the operation start position and controls the main body of the robot 12 to wait at the operation start position until a new item 41 enters the robot's operation area (step S101).

[0058] Furthermore, when the control unit 23 controls the velocity vector of the robot 12 moving via the moving device 13 and the velocity vector of the position of the end effector 31 of the robot 12, the velocity vector component in the X-axis direction (movement direction of the robot 12's main body moving via the moving device 13) is generated by appropriately sharing the velocity vector of the robot 12 and the velocity vector of the position of the end effector 31 of the robot 12. That is, the velocity vector component in the X-axis direction (movement direction of the robot 12's main body moving via the moving device 13) can be equally shared by the velocity vector of the robot 12 and the velocity vector of the position of the end effector 31 of the robot 12, or it can be shared in any proportion. Several examples of how the velocity vector of the robot 12 and the velocity vector of the position of the end effector 31 of the robot 12 are shared are given.

[0059] According to the first method, the control unit 23 performs control such that, in the direction of movement of the main body of the robot 12 via the moving device 13, i.e., the X-axis direction, the moving distance of the robot 12 (main body) via the moving device 13 is greater than the moving distance of the end effector 31 of the robot 12.

[0060] According to the second method, the control unit 23 performs control such that, in the direction of movement of the main body of the robot 12 via the moving device 13, i.e., the X-axis direction, the velocity vector of the robot 12 moving via the moving device 13 is greater than the velocity vector of the position of the end effector 31 of the robot 12.

[0061] These first and second methods, through the moving device 13, enable the main body of the robot 12 to move as much as possible in the X-axis direction, while minimizing the movement of the end effector 31 of the robot 12 in the X-axis direction. This prevents the robot 12's arm from reaching its dead zone limit and exceeding its range of motion. Furthermore, by further reducing the control burden on the X-axis component of the robot's end effector 31's velocity vector and placing greater emphasis on the control of the Y-axis and Z-axis components, the robot 12's operational accuracy can be improved. In particular, even if the object 41 suddenly moves significantly in the X-axis direction, the moving device 13 can quickly move the main body of the robot 12 in the X-axis direction, thereby minimizing the impact on the robot 12's original operation.

[0062] According to the third method, the control unit 23 controls the movement of the robot 12's end effector 31 so that its velocity vector is greater than the velocity vector of the robot 12 moving via the moving device 13. Normally, the acceleration of the moving device 13 is less than that of the robot 12's end effector 31, resulting in poorer following of the item 41 transported by the conveyor 11. Therefore, in order to quickly follow the item 41 transported by the conveyor 11, in the third method, the movement rate of the robot 12's end effector 31 is prioritized over the movement rate of the robot 12 moving via the moving device 13. For example, when the item 41 transported by the conveyor 11 approaches the end of the robot's work area, or the moving device 13 approaches the end of its movable range, and the remaining time for the robot 12 to perform its work is limited, the third method controls the movement so that the velocity vector of the robot 12's end effector 31 is greater than the velocity vector of the robot 12 moving via the moving device 13, thereby enabling the robot 12's end effector 31 to quickly follow the item 41 transported by the conveyor 11.

[0063] The first, second, and third methods can be combined appropriately or selectively switched.

[0064] Explanation of reference numerals in the attached figures

[0065] 1 Production System

[0066] 11 Conveying Device

[0067] 12 robots

[0068] 13 mobile devices

[0069] 14 First Control Device

[0070] 15 Second Control Device

[0071] 21 sensors

[0072] 22 Computing Department

[0073] 23 Control Department

[0074] 14 First Control Device

[0075] 15 Second Control Device

[0076] 31 end effector

[0077] 41 items

[0078] 41A, 41B Fitting Parts

[0079] 42 parts

[0080] 42A, 42B Fitting Parts

[0081] Velocity vector of 100 items

[0082] Velocity vector of 200 robots

[0083] The velocity vector of the end effector of the 300 robot.

Claims

1. A production system comprising: a conveying device for conveying articles, a robot for performing operations on the articles conveyed by the conveying device, and a moving device for moving the robot. Its features are, The production system has the following features: A sensor that acquires position information of the item being transported by the conveying device; The computing unit calculates the velocity vector of the item being transported by the conveying device based on the position information obtained by the sensor; and The control unit controls the velocity vector of the robot moving via the mobile device and the velocity vector of the robot's end effector position when the direction of movement of the item transported by the conveying device is different from the direction of movement of the robot moving via the mobile device, such that the sum of the velocity vector of the robot moving via the mobile device and the velocity vector of the robot's end effector position is consistent with the velocity vector of the item transported by the conveying device. The control unit controls the robot to move a greater distance than the position of the robot's end effector by means of the moving device.

2. A production system comprising: a conveying device for conveying articles, a robot for performing operations on the articles conveyed by said conveying device, and a moving device for moving said robot. Its features are, The production system has the following features: A sensor that acquires position information of the item being transported by the conveying device; The computing unit calculates the velocity vector of the item being transported by the conveying device based on the position information obtained by the sensor; and The control unit controls the velocity vector of the robot moving via the mobile device and the velocity vector of the robot's end effector position when the direction of movement of the item transported by the conveying device is different from the direction of movement of the robot moving via the mobile device, such that the sum of the velocity vector of the robot moving via the mobile device and the velocity vector of the robot's end effector position is consistent with the velocity vector of the item transported by the conveying device. The control unit controls the robot to move such that the velocity vector of the robot via the mobile device is greater than the velocity vector of the position of the robot's end effector.

3. A production system comprising: a conveying device for conveying articles, a robot for performing operations on the articles conveyed by the conveying device, and a moving device for moving the robot. Its features are, The production system has the following features: A sensor that acquires position information of the item being transported by the conveying device; The computing unit calculates the velocity vector of the item being transported by the conveying device based on the position information obtained by the sensor; and The control unit controls the velocity vector of the robot moving via the mobile device and the velocity vector of the robot's end effector position when the direction of movement of the item transported by the conveying device is different from the direction of movement of the robot moving via the mobile device, such that the sum of the velocity vector of the robot moving via the mobile device and the velocity vector of the robot's end effector position is consistent with the velocity vector of the item transported by the conveying device. The control unit controls the robot so that the velocity vector of the position of the robot's end effector is greater than the velocity vector of the robot moving through the mobile device.

4. The production system according to any one of claims 1 to 3, characterized in that, The mobile device enables the robot to move back and forth in one direction.

5. The production system according to claim 1, characterized in that, The control unit controls the robot to move such that the velocity vector of the robot via the mobile device is greater than the velocity vector of the position of the robot's end effector.

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