Robot system

Abstract

To provide a robot system that can improve convenience for an operator.SOLUTION: A robot system 1 comprises: a switching control part that switches an operation state of a welding robot 3 to either of a cooperation state where the robot operates in cooperation with an operator and a non-cooperation state where the robot operates without cooperating with the operator; a contact sensing part that senses contact with the welding robot 3; an operation restricting part that when the operation state of the welding robot 3 is the cooperation state and when the contact sensing part senses contact with the welding robot 3, restricts operation of the welding robot 3; a state notifying part that outputs notifications whose contents are different depending on whether the operation state is the cooperation state or the non-cooperation state; and a failure sensing part that senses a failure of the state notifying part. When the failure sensing part senses a failure of the state notifying part, the switching control part fixes the operation state of the welding robot 3 to the cooperation state.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a robot system. [Background technology]

[0002] The following Patent Document 1 discloses a collaborative robot that switches between a collaborative state in which the robot's operations are restricted when it detects that a person or object has entered a dangerous area, and a non-collaborative state in which the robot operates normally without detecting a person or object.As one method for making it easier to visually confirm whether the robot has switched to the collaborative state or the non-collaborative state, the following Patent Document 2 discloses that the robot is equipped with a light-emitting diode that changes its light color depending on the state of the robot. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2022-165821 [Patent Document 2] Patent Publication No. 2021-45820 Summary of the Invention [Problem to be solved by the invention]

[0004] However, even if a robot is equipped with an LED, if the LED breaks down, for example, a worker working in a collaborative area with the robot will no longer be able to visually check the robot's status, thereby reducing convenience for the worker.

[0005] Therefore, an object of the present invention is to provide a robot system that can improve convenience for workers. [Means for solving the problem]

[0006] A robot system according to one aspect of the present invention comprises a switching control unit that switches the operating state of an industrial robot between a collaborative state in which the robot operates in collaboration with a worker and a non-collaborative state in which the robot operates without collaborating with a worker; a contact detection unit that detects contact with the industrial robot; an operation restriction unit that restricts the operation of the industrial robot when the operating state is the collaborative state and contact with the industrial robot is detected by the contact detection unit; a status notification unit that outputs notifications with different content depending on whether the state is the collaborative state or the non-collaborative state; and a failure detection unit that detects a failure in the status notification unit, and the switching control unit fixes the operating state to the collaborative state when the failure detection unit detects a failure in the state notification unit.

[0007] According to this aspect, the operating state of the industrial robot can be switched between a collaborative state and a non-collaborative state, and if the operating state of the industrial robot is in the collaborative state and contact with the industrial robot is detected, the operation of the industrial robot can be restricted, and if a failure is detected in the state notification unit that outputs notifications with different content depending on whether the state is collaborative or non-collaborative, the operating state of the industrial robot can be fixed to the collaborative state.

[0008] This makes it possible to restrict the operation of the industrial robot if contact is detected while the industrial robot is operating in a collaborative state, and if the state notification unit that distinguishes between a collaborative state and a non-collaborative state fails, it becomes possible to fix the operating state of the industrial robot to a collaborative state.

[0009] In the above aspect, when the mode of the industrial robot is a mode in which an operator operates the industrial robot and teaches it how to operate, the switching control unit may not fix the operating state to the collaborative state even if the failure detection unit detects a failure in the state notification unit.

[0010] According to this aspect, when an operator operates an industrial robot in a non-collaborative state and teaches the robot an operation, even if the status notification unit breaks down, the operator can continue working in a non-collaborative state.

[0011] In the above aspect, when the failure detection unit detects a failure in the status notification unit, the switching control unit may cause an external terminal device to display a message or video notifying the user that the status notification unit has failed.

[0012] According to this aspect, the operator can confirm that the status notification unit has failed, for example, on a terminal device such as a teach pendant.

[0013] In the above aspect, when the operation state is fixed to the cooperation state, the switching control unit may output a sound to notify that the operation state is the cooperation state.

[0014] According to this aspect, the worker can auditorily confirm, by the notification sound, that the state notification unit has failed and is fixed in the cooperative state.

[0015] In the above aspect, the state notification unit may include a plurality of light-emitting diodes, and the switching control unit may fix the operating state to the cooperative state when the failure detection unit detects a failure in at least one of the light-emitting diodes.

[0016] According to this aspect, if even one of the plurality of light-emitting diodes fails, the operating state of the industrial robot can be fixed to the cooperative state. [Effects of the Invention]

[0017] According to the present invention, it is possible to provide a robot system that can improve convenience for workers. [Brief explanation of the drawings]

[0018] [Figure 1] FIG. 1 is a diagram illustrating a configuration of a robot system according to an embodiment. [Figure 2] 2 is a diagram illustrating an example of the functional configuration of a control unit of the robot control device of FIG. 1. DETAILED DESCRIPTION OF THE INVENTION

[0019] A preferred embodiment of the present invention will be described with reference to the accompanying drawings. In each drawing, components with the same reference numerals have the same or similar configurations. Furthermore, since the drawings are schematic, the dimensions and proportions of each component may differ from those of the actual components.

[0020] FIG. 1 is a diagram illustrating the configuration of a robot system 1 according to an embodiment. The robot system 1 includes, for example, a robot control device 2 and a welding robot 3. The robot control device 2 and the welding robot 3 can be connected via a network, for example, a wired network such as a communication cable, or a wireless network. The robot system 1 may also include a teaching pendant. The teaching pendant can be connected to the robot control device 2 and is, for example, a terminal device used by an operator to teach the welding robot 3 how to operate.

[0021] The robot control device 2 is a control unit that controls the operation of the welding robot 3, and includes, for example, a control unit 21, a storage unit 22, a communication unit 23, and a welding power supply unit 24.

[0022] Control unit 21 is a processor that controls welding robot 3 and welding power supply unit 24 by executing work programs such as a welding program stored in memory unit 22. Each function of control unit 21 will be described later. Communication unit 23 controls communication with each device connected via a network.

[0023] Welding power supply 24 supplies welding current, welding voltage, and the like to welding robot 3 in accordance with predetermined welding conditions, for example, to generate an arc between the tip of the welding wire and the workpiece. The welding conditions include data items such as welding conditions, welding start position, welding end position, welding distance, and welding torch posture. The welding conditions include data items such as welding current, welding voltage, welding speed, wire feed speed, and workpiece thickness. Welding power supply 24 may be provided separately from robot control device 2.

[0024] The welding robot 3 is a manipulator that performs arc welding on a welding target in accordance with welding conditions set in the robot control device 2, and is also a collaborative robot that works in cooperation with humans. Therefore, a worker can touch and directly operate the articulated arm of the welding robot 3, and can perform arc welding while directly operating it. The welding robot 3 can also detect external forces applied to the articulated arm.

[0025] The welding robot 3 includes, for example, a multi-joint arm mounted on a base member fixed to the floor of a factory, a welding torch which is one of the tools connected to the tip of the multi-joint arm, a torque sensor 31, and a light-emitting unit 32.

[0026] The torque sensor 31 is provided, for example, on the output side of the motor and reducer that drive each axis of the articulated arm, and detects the torque applied to each axis. By using the detection value of the torque sensor 31 provided on each axis, it is possible to detect contact (including collision) of a person or object with the articulated arm of the welding robot 3.

[0027] Light-emitting unit 32 is, for example, a light-emitting diode (LED) and is attached to the outer surface of welding robot 3. A full-color LED, a three-color LED, or a plurality of LEDs of different colors may be used as light-emitting unit 32. Note that light-emitting unit 32 does not necessarily have to be attached to welding robot 3, and may also be placed within a range visible to the worker operating welding robot 3 (for example, on a safety fence, etc.).

[0028] 2, a description will be given of some of the functions of the control unit 21 of the robot control device 2. The control unit 21 includes, as functional components, a failure detection unit 211, a switching control unit 212, a contact detection unit 213, and an operation restriction unit 214, for example.

[0029] The failure detection unit 211 detects a failure of the light-emitting unit 32. Specifically, when the failure detection unit 211 detects that a light-emitting diode constituting the light-emitting unit 32 does not light up normally, the failure detection unit 211 detects that the light-emitting unit 32 has failed. The fact that the light-emitting diode does not light up normally can be detected, for example, by comparing the current flowing in the path connecting the power supply and the light-emitting diode or the terminal voltage of the light-emitting diode with a predetermined reference value.

[0030] The switching control unit 212 switches the operating state of the welding robot 3 between a cooperative state in which the robot operates in cooperation with an operator and a non-cooperative state in which the robot operates without cooperation with an operator. The operating state and the non-cooperative state can be set by the operator using, for example, a teach pendant.

[0031] The collaborative state is an operating state in which a worker works next to the welding robot 3 in collaboration with the welding robot 3. In the collaborative state, contact with the welding robot 3 is detected, and when contact is detected, the operation of the welding robot 3 is suppressed to below a predetermined speed, and the welding robot 3 is restricted so that it cannot generate more than a specified force (torque).

[0032] The non-collaboration state is an operating state other than the collaboration state, and is, for example, a state in which the welding robot 3 is operated according to a work program or welding conditions. In the non-collaboration state, contact with the welding robot 3 is not detected, and the welding robot 3 can be operated without restrictions.

[0033] The switching control unit 212 causes the light-emitting unit 32 to output different lights depending on whether the state is cooperative or non-cooperative. The different lights may be different in color or lighting pattern, such as blinking intervals. It is sufficient if the worker can visually distinguish between the cooperative state and the non-cooperative state by the different lights.

[0034] When the failure detection unit 211 detects a failure of the light-emitting unit 32, the switching control unit 212 fixes the operating state of the welding robot 3 to the cooperative state. In other words, when the failure of the light-emitting unit 32 is detected, the switching control unit 212 does not set the operating state of the welding robot 3 to the non-cooperative state until the failure of the light-emitting unit 32 is resolved.

[0035] Here, when light-emitting unit 32 is configured with multiple light-emitting diodes, if a failure of at least one light-emitting diode is detected, switching control unit 212 preferably fixes the operating state of welding robot 3 to the cooperative state. This makes it possible to fix the operating state of welding robot 3 to the cooperative state even if even one of the multiple light-emitting diodes fails.

[0036] Furthermore, when the welding robot 3 is in the teaching mode, it is preferable that the switching control unit 212 does not fix the operating state of the welding robot 3 to the collaboration state even if the failure detection unit 211 detects a failure in the light-emitting unit 32. The reason for this will be described below.

[0037] The teaching mode is a mode in which an operator teaches the operation of the welding robot 3. This teaching mode can be implemented in both a collaborative state and a non-collaborative state. Therefore, in a collaborative state, an operator can also implement the teaching mode while operating the articulated arm of the welding robot 3.

[0038] At this time, if a torque exceeding a threshold value is applied to the articulated arm of the welding robot 3, contact with the welding robot 3 is detected and the operation of the welding robot 3 is restricted, which may interfere with the teaching work. To avoid this, when implementing the teaching mode, the worker can operate the welding robot 3 in a non-collaborative state in which contact is not detected.

[0039] When operating in this manner, if the operating state of the welding robot 3 is fixed to the cooperative state due to a failure of the light-emitting unit 32, the convenience for the worker will be impaired. Therefore, when operating in this manner, it is desirable to maintain the operating state of the welding robot 3 in the non-cooperative state even if the light-emitting unit 32 fails. By maintaining the non-cooperative state, the worker can continue working in the non-cooperative state, thereby improving the convenience for the worker.

[0040] In addition to the teaching mode, the modes of the welding robot 3 can include, for example, a welding mode for making the welding robot 3 perform welding, and an adjustment mode for adjusting welding conditions, etc.

[0041] The contact detection unit 213 detects contact with the welding robot 3. Specifically, when the detection value of any of the torque sensors 31 provided on each axis of the articulated arm of the welding robot 3 is equal to or greater than a threshold value, the contact detection unit 213 determines that a person or object has come into contact with the articulated arm of the welding robot 3, and detects the contact.

[0042] The operation restriction unit 214 restricts the operation of the welding robot 3 when the operation state of the welding robot 3 is the collaboration state and the contact detection unit 213 detects contact with the welding robot 3 .

[0043] Restricting the operation of the welding robot 3 includes, for example, limiting the operation of the welding robot 3 to less than a predetermined speed so that the welding robot 3 cannot exert more than a specified force, or stopping the operation of the welding robot 3.

[0044] As described above, the robot system 1 according to the embodiment can switch the operating state of the welding robot 3 between a cooperative state and a non-cooperative state, and when the operating state of the welding robot 3 is the cooperative state and contact with the welding robot 3 is detected, the operation of the welding robot 3 can be restricted. Furthermore, when a malfunction of the light-emitting unit 32, which emits different light depending on whether it is in the cooperative state or the non-cooperative state, is detected, the operating state of the welding robot 3 can be fixed to the cooperative state in which contact is detected.

[0045] This allows the operation of the welding robot 3 to be restricted if contact is detected while operating in a collaborative state, and if the light-emitting unit 32 that visually indicates the collaborative state and non-collaborative state fails, the operating state of the welding robot 3 can be fixed to the collaborative state in which contact is detected.

[0046] Therefore, the robot system 1 according to the embodiment can improve convenience for the worker.

[0047] [Variations] It should be noted that the present invention is not limited to the above-described embodiment, and can be embodied in various other forms without departing from the spirit of the present invention. Therefore, the above-described embodiment is merely illustrative in all respects and should not be interpreted as being limiting.

[0048] For example, in the above-described embodiment, the switching control unit 212 of the robot control device 2 fixes the operating state of the welding robot 3 to the collaborative state when the failure detection unit 211 detects a failure in the light-emitting unit 32, but the processing to be performed when a failure in the light-emitting unit 32 is detected is not limited to this.

[0049] For example, when a failure of the light-emitting unit 32 is detected, the switching control unit 212 of the robot control device 2 may transmit a message or image informing the operator of the failure of the light-emitting unit 32 to an external terminal device such as a teach pendant to display the message or image. This allows the operator to confirm that the light-emitting unit 32 has failed on the terminal device such as the teach pendant.

[0050] Furthermore, when a failure of the light-emitting unit 32 is detected and the operating state of the welding robot 3 is fixed to the collaboration state, the switching control unit 212 of the robot control device 2 may output a sound to notify that the operating state of the welding robot 3 has been fixed to the collaboration state. The sound to notify may be a melody or a voice. In this case, it is preferable to place a speaker (sound output unit) on or near the welding robot 3. This allows the worker to audibly confirm that the light-emitting unit 32 has failed and the welding robot 3 has been fixed to the collaboration state by the sound of the notification.

[0051] Furthermore, in the above-described embodiment, the failure detection unit 211 of the robot control device 2 detects a failure of the light-emitting unit 32, but the target of failure detection is not limited to the light-emitting unit 32. For example, the failure detection unit 211 may detect a failure of a sound output unit that outputs different sounds depending on whether the robot is in a cooperative state or a non-cooperative state, or a failure of a display unit that displays different messages or images depending on whether the robot is in a cooperative state or a non-cooperative state. In other words, the failure detection unit 211 may detect a failure of a status notification unit that outputs notifications with different content (light, sound, message, or image) depending on whether the robot is in a cooperative state or a non-cooperative state.

[0052] In this case, when the failure detection unit 211 detects a failure in the status notification unit, the switching control unit 212 fixes the operating state of the welding robot 3 to the collaborative state, but when the welding robot 3 is in the teaching mode, it is preferable that the switching control unit 212 does not fix the operating state of the welding robot 3 to the collaborative state even if a failure in the status notification unit is detected. Furthermore, when the switching control unit 212 detects a failure in the status notification unit, the switching control unit 212 may transmit a message or video notifying that the status notification unit has failed to an external terminal device such as a teach pendant for display, or may sound a buzzer.

[0053] Furthermore, although the above-described embodiment has been described using the welding robot 3, the present invention is not limited to this. For example, the present invention can be applied to industrial robots including handling robots that perform picking and the like, in addition to welding robots. In this case, the welding program and welding target used in the above embodiment can be replaced with a work program and work target, respectively. [Explanation of symbols]

[0054] 1... robot system, 2... robot control device, 3... welding robot, 21... control unit, 22... memory unit, 23... communication unit, 24... welding power supply unit, 31... torque sensor, 32... light emitting unit, 211... failure detection unit, 212... switching control unit, 213... contact detection unit, 214... operation restriction unit

Claims

1. a switching control unit that switches the operating state of the industrial robot between a collaborative state in which the industrial robot operates in collaboration with a worker and a non-collaborative state in which the industrial robot operates without collaborating with a worker; a contact detection unit that detects contact with the industrial robot; an operation limiting unit that limits an operation of the industrial robot when the operation state is the cooperative state and the contact detecting unit detects contact with the industrial robot; a state notification unit that outputs a notification with different content depending on whether the state is in the cooperative state or the non-cooperative state; a failure detection unit that detects a failure of the status notification unit; Equipped with the switching control unit fixes the operation state to the cooperation state when the failure detection unit detects a failure in the state notification unit. Robot system.

2. When the mode of the industrial robot is a mode in which an operator operates the industrial robot to teach it an operation, the switching control unit does not fix the operating state to the collaborative state even if the failure detection unit detects a failure in the state notification unit. The robot system according to claim 1 .

3. When the failure detection unit detects a failure in the status notification unit, the switching control unit causes an external terminal device to display a message or video notifying that the status notification unit has failed. The robot system according to claim 1 .

4. When the operation state is fixed to the cooperation state, the switching control unit outputs a sound to notify the user that the operation state is the cooperation state. The robot system according to claim 1 .

5. the status notification unit includes a plurality of light-emitting diodes, the switching control unit fixes the operation state to the cooperative state when the failure detection unit detects a failure in at least one of the light-emitting diodes. The robot system according to claim 1 .

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