Production System

Abstract

This invention relates to a production system comprising a conveying device for transporting items, a robot for operating on items transported by the conveying device, and a moving device for moving the robot. The system includes: a sensor for acquiring position information of the items transported by the conveying device; a calculation unit for calculating the velocity vector of the items transported 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 and the velocity vector of the robot's end effector position when the direction of movement of the items transported by the conveying device differs from the direction of movement of the robot moved by the moving device, such that the sum of the velocity vector of the robot and the velocity vector of the robot's end effector position is consistent with the velocity vector of the items transported by the conveying device.

Description

[Technical Field]

[0001] This invention relates to a production system. [Previous Technology]

[0002] A production system is known in which a robot performs operations on items transported by a conveying device. The production system includes a conveying device for transporting items, a robot performing operations on the items transported by the conveying device, and a moving device for moving the robot. Maintaining a suitable positional relationship between the robot and the items is important in the production system.

[0003] For example, a following control method for a robot with a transfer axis is known, which enables a robot body and a transfer axis that moves the robot body in a specific direction to follow a continuous line. The method is characterized by: controlling the transfer axis of the robot with the transfer axis so that the movement speed of the line is divided into units of time, calculating the average speed per unit time, and following the line at the average speed per unit time. Based on the result, the following deviation between the transfer axis and the line is taken as the robot deviation in the direction of the transfer axis, and the joint axis of the robot body is controlled to make correction (for example, see Patent Document 1).

[0004] For example, a known operating system includes: a conveying device for conveying an article; a movable platform; an operating unit fixed to the platform and performing operations on the article conveyed by the conveying device; a vision sensor fixed to the platform and acquiring visual information of the article conveyed by the conveying device or a mark formed on the conveying device; a detection unit that processes the visual information acquired by the vision sensor to detect at least the position of the article or the mark; a calculation unit that calculates the conveying speed of the conveying device based on the position of the article or the mark detected by the detection unit; and a drive control unit that drives 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 mechanism for conveying workpieces, a robot performing specific operations on the workpieces conveyed by the workpiece conveying mechanism, and a robot movement drive mechanism enabling the robot to move along a workpiece conveying path. The device is characterized by comprising: a workpiece position detection mechanism that detects the conveying direction position of the workpieces conveyed by the workpiece conveying mechanism; a robot position detection mechanism that detects the position of the robot driven by the robot movement drive mechanism in the workpiece conveying direction; a robot control mechanism that controls the robot; a synchronization control mechanism that controls the robot movement drive mechanism to make the robot move synchronously following the conveyed workpieces; and a coordination control mechanism that uses the workpiece position detected by the workpiece position detection mechanism and the robot position detected by the robot position detection mechanism to coordinate the control performed by the robot control mechanism with the control performed by the synchronization control mechanism (for example, see Patent Document 3). [Prior Art Documents] [Patent Documents]

[0006] [Patent Document 1] Japanese Patent Publication No. 07-060327 [Patent Document 2] Japanese Patent Publication No. 2019-072792 [Patent Document 3] Japanese Patent Publication No. 08-072764 [Summary of the Invention]

[0007] [The problem the invention aims to solve]

[0008] In a production system, when the direction of movement of an item transported by a conveying device is the same as the direction of movement of a robot moved by a mobile device, if an encoder or other machine is used to calculate the speed of the conveying device, and the robot is moved at the same speed as the conveying device to follow the item, the positional relationship in which the robot can properly perform operations on the item can be maintained. However, the direction of movement of the item transported by the conveying device and the direction of movement of the robot moved by the mobile device may sometimes be different. For example, due to various factors such as the motion accuracy of the conveying device and / or the mobile device and vibration, the direction of movement of the item and / or the robot may sometimes deviate from the ideal direction, and the relative distance between the robot and the item may change. Also, for example, the direction of movement of the item transported by the conveying device may sometimes be curved rather than straight, or the item may sometimes be transported by the conveying device in a direction inclined relative to the horizontal plane. When the direction of movement of an item transported by a conveyor is different from the direction of movement of a robot moved by a mobile device, controlling the conveyor's speed based solely on the encoder-measured speed of the item cannot enable the robot to follow it. Therefore, it is desirable to develop a production system that maintains a suitable positional relationship for the robot to perform operations on the item even when the direction of movement of the item transported by the conveyor is different from the direction of movement of the robot moved by the mobile device. [Technical Means for Solving the Problem]

[0009] According to one aspect of the present invention, a production system is provided, comprising a conveying device for conveying items, a robot for performing operations on items conveyed by the conveying device, and a moving device for moving the robot, and including: a sensor for acquiring position information of the items conveyed by the conveying device; a calculation unit for calculating the velocity vector of the items 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 moved by the moving device and the velocity vector of the position of the robot's end effector when the direction of movement of the items conveyed by the conveying device is different from the direction of movement of the robot moved by the moving device, such that the sum of the velocity vector of the robot moved by the moving device and the velocity vector of the position of the robot's end effector is consistent with the velocity vector of the items conveyed by the conveying device. [Effects of the Invention]

[0010] According to one aspect of the present invention, a production system can be realized in which the robot can perform operations on the items appropriately, even when the direction of movement of the items transported by the conveying device is different from the direction of movement of the robot moved by the moving device.

Implementation Method

[0012] The production system will be described with reference to the following diagrams. For ease of understanding, the scale of these diagrams has been appropriately changed. The forms shown in the diagrams are examples of implementation and are not limited to the illustrated embodiments. Furthermore, in the following description, "velocity" refers to a vector representing the change in an object per unit time and its direction. In this specification, "velocity" is expressed as "velocity vector" for more explicit representation as a vector. Also, "speed" is a scalar representing the magnitude of speed.

[0013] Figure 1 is a perspective view of a production system according to one embodiment of the present invention.

[0014] The production system 1 includes a conveying device 11 for conveying items 41, a robot 12 for performing operations on the items 41 conveyed by the conveying device 11, and a moving device 13 for moving the robot 12. As an example, the production system 1 is described in which the robot 12 performs the operation of assembling parts 42 on the items 41 conveyed by the conveying device 11.

[0015] The production system 1 establishes a reference coordinate system (world coordinate system) relative to which the position and posture of the robot 12 remain stationary despite changes. In this reference coordinate system, the origin is fixed, and consequently, the directions of the coordinate axes are fixed. The reference coordinate system has mutually orthogonal X-axis, Y-axis, and Z-axis as coordinate axes. Furthermore, the W-axis is set as the coordinate axis around the X-axis. The P-axis is set as the coordinate axis around the Y-axis. The R-axis is set as the coordinate axis around the Z-axis.

[0016] Furthermore, the production system 1 includes a tool coordinate system with an origin set at any position on the end effector (working tool) 31 of the robot 12. The position and orientation of the tool coordinate system change 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 the robot 12 corresponds to the position of the tool tip point in the reference coordinate system (the origin position of the tool coordinate system). Also, the orientation of the end effector 31 of the robot 12 corresponds to the orientation of the tool coordinate system relative to the reference coordinate system.

[0017] The conveying device 11 for transporting the item 41 can be of any shape. Furthermore, the direction (movement direction) of the conveying device 11 for transporting the item 41 can be any direction along the X-axis and Y-axis on the horizontal plane, or any direction along the Y-axis perpendicular to the horizontal plane. In Figure 1, as an 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 along the X-axis and / or Y-axis on the horizontal plane. Also, the AGV as the conveying device 11 can move on a slope with any angle of inclination relative to the horizontal plane; in this case, the AGV's movement direction is the X-axis, Y-axis, and / or Z-axis. Furthermore, the conveying device 11 is not limited to the AGV shown here. For example, it may be a belt conveyor, a conveying device with a transfer shaft that moves on a track for guiding movement, a magnetic levitation conveying device, or an electromagnetic levitation conveying device.

[0018] The moving device 13, which moves the robot 12 (its body), can be of any form. The moving device 13 causes the robot 12 to reciprocate in one direction on a horizontal plane. In Figure 1, as an example, the moving device 13 causes the body of the robot 12 to reciprocate in the positive (+) and negative (-) directions along the X-axis. For example, the moving device 13 is a moving device with a transfer axis that causes the support platform supporting the robot 12 to move on a track for guiding movement using a motor (not shown) as a drive source. Furthermore, the moving device 13 is not limited to this form, and 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, AGV, magnetic levitation transport device, or electromagnetic levitation transport device.

[0019] The robot 12 performs arbitrary operations on the item 41 transported by the conveying device 11. The end effector 31 installed on the robot 12 is an arbitrary working tool corresponding to the operation performed by the robot 12. In Figure 1, as an example, the end effector 31 is a hand that holds or releases the part 42. The hand is, for example, an adhesive hand that holds the surface of the part 42 by suction. Furthermore, the end effector 31 installed on the robot 12 is not limited to this form. In a production system that performs welding operations, it can be used as a welding tool, and in a production system that performs painting operations, it can be used as a tool for applying paint to the surface of an item.

[0020] In the example shown in Figure 1, the robot 12 assembles the part 42 onto the article 41 by engaging the engagement portions 42A and 42B of the part 42 held by the hand, which is the end effector 31, with the engagement portions 42A and 42B of the article 41 respectively. For example, the article 41 is the body of a car, and the part 42 is a car door or a tire.

[0021] In order to enable the end effector 31 of the robot 12 to follow the movement of the items transported by the conveying device 11, a production system 1 according to one embodiment of the present invention includes a sensor 21, a computing unit 22, and a control unit 23.

[0022] Sensor 21 acquires position information of the item 41 transported by the conveying device 11. Sensor 21 can obtain the positional relationship between item 41 and robot 12. In the illustrated example, sensor 21 is disposed on the body of robot 12 to sense the position of item 41. As an alternative example, sensor 21 can also be disposed above robot 12 and item 41 (e.g., on the ceiling of the room housing production system 1) so that both robot 12 and item 41 can sense each other.

[0023] The sensor 21 obtains position information of the object 41 in various ways, such as stereo camera method and pulse radar method.

[0024] The sensor 21, which utilizes a stereo camera, includes: two two-dimensional cameras that capture two-dimensional images; and a processing unit that obtains the position information of the object 41 based on the parallax of the two images captured by the two two-dimensional cameras and through image processing. 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. Furthermore, the sensor 21 includes a projector that projects patterned light, such as stripes, onto the object 41. The projected pattern on the object 41 can be captured by the two-dimensional cameras, and the position information of the object 41 can be obtained based on the captured image.

[0025] The sensor 21 using pulse radar includes: a transmitter that transmits radio waves; a receiver that receives reflected waves from the item 41; and a processing unit that obtains the location information of the item 41 based on the relationship between the radio waves transmitted by the transmitter and the reflected waves received by the receiver.

[0026] Furthermore, when the conveying device 11 includes a conveying device (such as an AGV) with a support platform that moves along 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.

[0027] The position information of the item 41 transported by the conveying device 11 is periodically obtained by the sensor 21 (for example, every few hundred ms) and sent to the computing unit 22.

[0028] The computing unit 22 calculates the velocity vector of the item 41 transported by the conveying device 11 based on the position information periodically acquired by the sensor 21. The velocity vector of the item 41 includes the "velocity" representing the variation of the item 41 per unit time and the "direction of movement" of the item 41 moving at that velocity.

[0029] The computing unit 22 includes an arithmetic processing device (processor). Examples of arithmetic processing devices include ICs (Integrated Circuits), LSIs (Large Scale Integration), CPUs (Central Processing Units), MPUs (Micro Processing Units), and DSPs (Digital Signal Processors). The computing unit 22, including the arithmetic processing device, is, for example, a functional module implemented by a computer program executed on the processor. For example, when the computing unit 22 is constructed as a computer program, the functions of the computing unit 22 can be implemented by causing the arithmetic processing device to operate according to the computer program. The computer program used to execute the processing of the computing unit 22 can be provided in the form of a computer-readable recording medium such as semiconductor memory, magnetic recording medium, or optical recording medium. Alternatively, the computing unit 22 can also be implemented as a personal computer having a semiconductor integrated circuit on which a computer program implementing the function is written.

[0030] Furthermore, the production system 1 is equipped with a first control device 14 and a second control device 15.

[0031] 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. Since the speed vector includes the "speed" representing the variation of the object per unit time and the "direction of movement" of the object moving at that speed, the control of the speed vector includes "speed control" and "direction control". For example, when the conveying device 11 includes an AGV, a magnetic levitation conveying device, or an electromagnetic levitation conveying device, the second control device 15 controls the speed and direction of movement of the item 41 caused by the conveying device 11. When the conveying device 11 includes a belt conveyor or a conveying device with a transfer shaft that moves on a track for transfer guidance, the direction of movement of the item 41 caused by the conveying device 11 has been predetermined, so the second control device 15 controls the speed at which the item 41 is conveyed by the conveying device 11.

[0032] 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. In addition to a control unit (not shown) for controlling the movement of the end effector 31 required for the operation of the article 41, the first control device 14 also has a control unit 23 for controlling the movement of the robot 12 caused by the moving device 13 and the positional 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 positional velocity vector of the end effector 31 of the robot 12 based on the velocity vector of the article 41 calculated by the calculation unit 22. More specifically, the control unit 23 controls the velocity vector of the robot 12 moved by the moving device 13 and the positional velocity vector of the end effector 31 of the robot 12, such that the sum of the velocity vector of the robot 12 moved by the moving device 13 and the positional velocity vector of the end effector 31 of the robot 12 is consistent with the velocity vector of the article 41 transported by the conveying device 11. Since the velocity vector includes the "velocity" representing the change in velocity of an object per unit time and the "direction of movement" of the object moving at that velocity, the control of the velocity vector includes both "velocity control" and "direction control". Details of the control processing for the movement performed by the control unit 23 and the position movement of the end effector 31 of the robot 12 will be described later.

[0033] The first control device 14 and the second control device 15 are equipped with an arithmetic processing unit (processor). Examples of arithmetic processing units include ICs, LSIs, CPUs, MPUs, and DSPs. The control unit 23, which includes the arithmetic processing unit in the first control device 14, is, for example, a functional module implemented by a computer program executed on the processor. For example, when the control unit 23 is constructed as a computer program, the function of the control unit 23 can be realized by causing the arithmetic processing unit to operate according to the computer program. The computer program used to execute 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 also be implemented as a semiconductor integrated circuit with a computer program implementing the function written in it.

[0034] The first control device 14 and the second control device 15 can also be configured as an integrated control device, and furthermore, the computing unit 22 can be included in the integrated control device. In addition, the computing unit 22 can be included in the first control device 14 or the second control device 15.

[0035] Next, the details of the control processing of the movement performed by the control unit 23 and the position movement of the end effector 31 of the robot 12 will be explained.

[0036] Figure 2 is a diagram showing the relationship between the velocity vector of the article transported by the conveying device, the velocity vector of the robot, and the velocity vector of the position of the robot's end effector in a production system according to one embodiment of the present invention. In Figure 2, reference numeral 100 represents the velocity vector of the article 41 calculated by the calculation unit 22. Reference numeral 200 represents the velocity vector of the robot 12 (body) controlled by the control unit 23, and reference numeral 300 represents the velocity vector of the position of the end effector 31 of the robot 12 controlled by the control unit 23.

[0037] The main body of robot 12 moves back and forth along the positive (+) and negative (-) directions of the X-axis by means of the movement device 13.

[0038] On the other hand, according to the configuration of the production system 1, in some cases, the item 41 transported by the conveying device 11 moves in a direction away from or close to the body of the robot 12 (Y-axis direction and / or Z-axis direction), and does not remain parallel to the movement direction of the robot 12 body. Furthermore, the production system 1 may also have the following configuration: the movement direction of the item 41 transported by the conveying device 11 is curved rather than linear, or the conveying device 11 transports the item 41 in a direction inclined relative to the horizontal plane. Moreover, according to the configuration of the production system 1, even in a production system 1 where the movement direction of the item 41 transported by the conveying device 11 is designed to be parallel to the movement direction of the robot 12 body, due to various factors such as the motion accuracy of the conveying device 11 and / or the moving device 13 and vibration, the movement direction of the item 41 and / or the movement direction of the robot 12 (body) may sometimes deviate from its original direction, and the relative distance between the robot 12 (body) and the item 41 may sometimes change.

[0039] Thus, in production system 1, a state may arise where the direction of movement of the item 41 transported by the conveying device 11 is different from the direction of movement of the robot 12 (body) moved by the moving device 13. Therefore, in one embodiment of the present invention, 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 transported by the conveying device 11 is different from the direction of movement of the robot 12 (body) moved by the moving device 13, the control unit 23 controls the velocity vector of the robot 12 (body) moved by 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 (body) moved by 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 transported by the conveying device 11. Therefore, even when the direction of movement of the item 41 transported by the conveying device 11 in the production system 1 is different from the direction of movement of the robot 12 (its body) moved by the moving device 13, the positional relationship in which the robot 12 can properly perform operations on the item can be maintained.

[0040] Since the moving device 13 can move the body of the robot 12 back and forth along the positive (+) and negative (-) directions of the X-axis, the velocity vector of the robot 12 controlled by the control unit 23 should ideally only have an X-axis component. However, in reality, the body of the robot 12 controlled by the control unit 23 undergoes slight changes in the Y-axis and / or Z-axis directions due to the motion accuracy and vibration of the moving device 13. Since the position information of the item 41 obtained by the sensor 21 represents the position of the item 41 relative to the 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, 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. In this way, it can also cope with the changes in the Y-axis direction and / or Z-axis direction of the robot 12 body caused by the motion accuracy and vibration of the moving device 13.

[0041] Furthermore, the velocity vector of the item 41 transported by the conveying device 11 can also be determined based on the design data or control data of the production system 1. However, as mentioned above, due to various factors such as the motion accuracy and vibration of the conveying device 11 and / or the moving device 13, the "actual" velocity vector of the item 41 may deviate from the "ideal" velocity vector of the item 41 determined according to the design content of the production system 1. In one embodiment of the present invention, the velocity vector of the item 41 calculated based on the position information of the item 41 obtained by the sensor 21, that is, based on the "actual" velocity vector of the item 41, is used to control the velocity vector 200 of the robot 12 and the velocity vector 300 of the end effector 31 of the robot 12. Therefore, compared with the case where the control is based on the velocity vector of the item 41 determined according to the design data or 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.

[0042] Figure 3 is a flowchart illustrating the operation flow of a production system according to one embodiment of the present invention. As an example, a production system 1 is described in which a robot 12 assembles parts 42 from an article 41 transported by a conveying device 11.

[0043] The robot's working area, in which the robot 12 can perform operations on the items 41 transported by the conveying device 11, is defined by the range of the items 41 that the conveying device 11 can transport, the range of motion of the robot 12's arm, and the range of motion of the robot 12's body caused by the moving device 13. For example, in a production system 1 where multiple items 41 are successively fed into the robot's working area by the conveying device 11, the robot 12 begins to follow and perform operations on the item 41 when it enters the robot's working area, and completes the robot 12's operations on the item 41 during the period until the item 41 leaves the robot's working area. In step S101, the control unit 23 controls the moving device 13 so that the robot 12's body is idle at the start position of the operation until the item 41 enters the robot's working area.

[0044] When the item 41 enters the robot's working area, in step S102, the sensor 21 obtains the position information of the item 41 being transported by the conveying device 11.

[0045] In step S103, the calculation unit 22 calculates the velocity vector of the item 41 transported 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.

[0046] In step S104, the control unit 23 controls the velocity vector of the robot 12 moved by 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 moved by 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 transported by the conveying device 11.

[0047] In step S104, the first control device 14 determines whether the robot 12 has completed its operation on the item 41.

[0048] If the first control device 14 determines in step S104 that the robot 12 has not yet completed the assembly operation of the item 41, it returns to step S102. The processing of steps S102 to S105 is repeated at a specific period (e.g., several hundred ms). During the repeated execution of steps S102 to S105, the first control device 14 controls the robot 12 to perform the assembly operation of parts 42 on the item 41. Furthermore, a two-dimensional camera for assembly operation is set near the end effector 31. The two-dimensional camera is used to photograph the item 41 at a high period (e.g., several ms), and pattern matching processing based on the photographed image is used to control the movement of the end effector 31 on the item 41 with high precision, and to perform the operation required to assemble parts 42 on the item 41.

[0049] If the first control device 14 determines in step S104 that the robot 12 has not yet completed the assembly operation of the item 41, then the processing of the item 41 ends. Then, the control unit 23 controls the robot 12 to move to the operation start position, and controls the robot 12 to stand by at the operation start position until a new item 41 enters the robot operation area (step S101).

[0050] Furthermore, when the control unit 23 controls the velocity vector of the robot 12 moving by 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 of the robot 12's body movement caused by the moving device 13 is appropriately 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. That is, the velocity vector component in the X-axis direction of the robot 12's body movement caused by 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 by the velocity vector of the robot 12 and the velocity vector of the position of the end effector 31 of the robot 12 in any proportion. Several examples of the sharing of the velocity vector of the robot 12 and the velocity vector of the position of the end effector 31 of the robot 12 will be listed.

[0051] According to the first embodiment, the control unit 23 performs control so that the moving distance of the robot 12 (body) moved by the moving device 13 in the moving direction of the robot 12 body caused by the moving device 13, i.e. the X-axis direction, is greater than the moving distance of the end effector 31 of the robot 12.

[0052] According to the second embodiment, the control unit 23 controls the velocity vector component of the movement direction of the robot 12 body caused by the moving device 13, i.e. the X-axis direction, so that the velocity in the velocity vector of the robot 12 moved by the moving device 13 is greater than the velocity in the velocity vector of the position of the end effector 31 of the robot 12.

[0053] In the first and second embodiments, the moving device 13 causes the robot 12 body to move as much as possible along the X-axis, while the robot 12 end effector 31 moves as little as possible along the X-axis. This prevents the robot 12's arm from reaching its dead 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 adjusting the control weights for the Y-axis and Z-axis components, the robot 12 can achieve higher operational precision. In particular, even if the object 41 suddenly moves significantly along the X-axis, the moving device 13 causes the robot 12 body to move rapidly along the X-axis, minimizing the impact on the robot 12's original operation.

[0054] According to the third embodiment, the control unit 23 controls the position of the end effector 31 of the robot 12 to have a velocity vector greater than the velocity vector of the robot 12 moved by the moving device 13. Generally, since the acceleration of the moving device 13 is worse than that of the end effector 31 of the robot 12, its following ability of the item 41 carried by the conveying device 11 is poor. Therefore, in order to quickly follow the item 41 carried by the conveying device 11, in the third embodiment, the moving speed of the end effector 31 of the robot 12 is prioritized over the moving speed of the robot 12 moved by the moving device 13. For example, when the item 41 transported by the conveying device 11 approaches the end of the robot's working area or the end of the movable range of the mobile device 13, and the robot 12 does not have much remaining working time, the third mode is used to control the robot 12 so that the velocity in the velocity vector of the position of the end effector 31 is greater than the velocity in the velocity vector of the robot 12 moving by the mobile device 13. In this way, the end effector 31 of the robot 12 quickly follows the item 41 transported by the conveying device 11.

[0055] Regarding the first, second and third forms, they can be executed in combination as appropriate, or selectively switched. [Simplified Explanation of the Diagram]

[0011] Figure 1 is a perspective view illustrating a production system according to one embodiment of the present invention. Figure 2 is a diagram showing the relationship between the velocity vector of the item transported by the conveying device, the velocity vector of the robot, and the velocity vector of the position of the robot's end effector in the production system according to one embodiment of the present invention. Figure 3 is a flowchart showing the operation flow of the production system according to one embodiment of the present invention.

Claims

1. A production system comprising a conveying device for transporting goods, a robot for performing operations on the goods transported by the conveying device, and a moving device for moving the robot, and further comprising: The system includes a sensor that acquires position information of the item being transported by the conveying device; a calculation unit that calculates the velocity vector of the item being transported by the conveying device based on the position information acquired by the sensor; and a control unit that, when the direction of movement of the item being transported by the conveying device is different from the direction of movement of the robot being moved by the mobile device, controls the velocity vector of the robot being moved by the mobile device and the velocity vector of the position of the robot's end effector, such that the sum of the velocity vector of the robot being moved by the mobile device and the velocity vector of the position of the robot's end effector is consistent with the velocity vector of the item being transported by the conveying device; and the control unit controls the movement of the robot being moved by the mobile device to be greater than the movement distance of the position of the robot's end effector.

2. A production system comprising a conveying device for transporting goods, a robot for performing operations on the goods transported by the conveying device, and a moving device for moving the robot, and further comprising: A sensor acquires position information of the item being transported by the conveying device; a calculation unit calculates the velocity vector of the item being transported by the conveying device based on the position information acquired by the sensor; and a control unit controls the velocity vector of the robot being transported by the mobile device and the velocity vector of the position of the robot's end effector when the direction of movement of the item being transported by the conveying device is different from the direction of movement of the robot being transported by the mobile device, such that the sum of the velocity vector of the robot being transported by the mobile device and the velocity vector of the position of the robot's end effector is consistent with the velocity vector of the item being transported by the conveying device; and the control unit controls the velocity vector of the robot being transported by the mobile device to be greater than the velocity vector of the position of the robot's end effector.

3. A production system comprising a conveying device for transporting goods, a robot for performing operations on the goods transported by the conveying device, and a moving device for moving the robot, and further comprising: The system includes a sensor that acquires position information of the item being transported by the conveying device; a calculation unit that calculates the velocity vector of the item being transported by the conveying device based on the position information acquired by the sensor; and a control unit that, when the direction of movement of the item being transported by the conveying device is different from the direction of movement of the robot being moved by the moving device, controls the velocity vector of the robot being moved by the moving device and the velocity vector of the position of the robot's end effector, such that the sum of the velocity vector of the robot being moved by the moving device and the velocity vector of the position of the robot's end effector is consistent with the velocity vector of the item being transported by the conveying device; and the control unit controls the system so that the velocity in the velocity vector of the position of the robot's end effector is greater than the velocity in the velocity vector of the robot being moved by the moving device.

4. A production system as described in any of claims 1 to 3, wherein the aforementioned moving device causes the robot to move back and forth in one direction.

5. The production system of claim 1, wherein the control unit controls the movement of the robot by the mobile device such that the velocity in the velocity vector of the robot is greater than the velocity in the velocity vector of the position of the robot's end effector.

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