Collaborative robot system

Abstract

To provide a collaborative robot system capable of further improving safety when restarting a collaborative robot stopped in operation due to contact of an object including an operator.SOLUTION: A collaborative robot system 100 includes: a collaborative robot 110 which has an arm and operates in one operation mode of a collaborative mode and a non-collaborative mode; a contact sensor 120 detecting contact of an object with the arm; a lamp 130 which displays the operation mode of the collaborative robot; and a control device 150 which controls the operations of the whole collaborative robot. The control device 150 stops the operation of the arm and blinks the lamp 130 when the contact sensor 120 detects contact during the collaborative mode. The control device restarts the collaborative robot 110 when the contact sensor 120 detects contact at a prescribed timing in accordance with a blinking pattern of the lamp 130.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a collaborative robot system including a collaborative robot that operates in either a collaborative mode or a non - collaborative mode.

Background Art

[0002] In the case of an industrial robot that shares a working area with an operator, i.e., a so - called collaborative robot, safety measures are required. These safety measures can be classified into intrinsic safety and functional safety. Intrinsic safety is the safety ensured by the structure and mechanism. For example, by taking a large gap between the arms, a structure is adopted in which it is difficult for an operator's finger to be pinched when the arms are folded. Functional safety is the safety ensured by control. For example, when the arm and the operator collide, the robot stops to prevent the collision.

[0003] Although intrinsic safety is a desirable measure, there is a problem that the degree of design freedom is lost due to restrictions on the shape and structure of the robot, such as taking a large gap between the arms. Therefore, for risks that cannot be addressed by intrinsic safety, a robot that addresses them with functional safety is used, and it is considered to operate in a non - collaborative mode where there are usually no restrictions due to functional safety, and implement functional safety when an operator approaches.

[0004] For example, Patent Document 1 discloses "a collaborative robot system including a robot arm and an operator can approach the robot arm". The collaborative robot system of Patent Document 1 includes "a plurality of proximity sensors attached to the robot arm for detecting the approach of an operator to the robot arm, and an arm control unit for selecting a proximity sensor used for operator detection from the plurality of proximity sensors according to the working procedure of the robot arm".

[0005] In Patent Document 1, it is stated that a capacitance sensor (proximity sensor) can also serve as a switch that stops a robotic arm when an operator approaches it, and as a man-machine interface that becomes a work start switch for the robotic arm when the operator intentionally touches the robotic arm again after the stop. In this case, the sensor processing unit and the arm control unit are assumed to have a function of restarting the robotic arm 1.

Prior Art Documents

Patent Documents

[0006]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0007] In the collaborative robot system of Patent Document 1, it is stated that "the stopped robotic arm can be restarted, improving the work efficiency of the operator." However, with such a configuration, the robotic arm will restart even when the operator touches the robotic arm again unintentionally. Therefore, in the collaborative robot system of Patent Document 1, functional safety cannot be sufficiently ensured, and there is room for further improvement.

[0008] In view of such problems, an object of the present invention is to provide a collaborative robot system that can further improve the safety when restarting a collaborative robot whose operation has been stopped by contact with an object including an operator.

Means for Solving the Problems

[0009] In order to solve the above problems, a typical configuration of the collaborative robot system according to the present invention includes a collaborative robot having an arm and operating in either a collaborative mode or a non-collaborative mode, a contact sensor for detecting that an object has come into contact with the arm, a lamp for displaying the operating mode of the collaborative robot, and a control device for controlling the operation of the entire collaborative robot. The control device stops the operation of the arm and blinks the lamp when the contact sensor detects contact during the collaborative mode. When the contact sensor detects contact at a predetermined timing according to the blinking pattern of the lamp, the collaborative robot is restarted.

[0010] When the contact sensor detects contact at a predetermined timing multiple times, the control device may restart the collaborative robot.

[0011] When the contact sensor detects contact during lighting in the blinking pattern and detects non-contact during extinguishing after that lighting, and this is repeated two or more times, the control device may restart the collaborative robot.

[0012] In order to solve the above problems, another configuration of the collaborative robot system according to the present invention includes a collaborative robot having an arm and operating in either a collaborative mode or a non-collaborative mode, a contact sensor for detecting that an object has come into contact with the arm, a lamp for displaying the operating mode of the collaborative robot, and a control device for controlling the operation of the entire collaborative robot. The control device stops the operation of the arm and lights the lamp in a predetermined lighting pattern with a predetermined color and a color different from the predetermined color when the contact sensor detects contact during the collaborative mode. When the contact sensor detects contact at a predetermined timing according to the lighting pattern of the lamp, the collaborative robot is restarted.

Effects of the Invention

[0013] According to the present invention, it is possible to provide a collaborative robot system that can further improve the safety when restarting a collaborative robot whose operation has been stopped due to contact with an object including an operator.

Brief Description of the Drawings

[0014]

Figure 1

Figure 2

Figure 3

Embodiments for Carrying Out the Invention

[0015] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. The dimensions, materials, and other specific numerical values shown in such embodiments are merely examples for facilitating understanding of the invention, and do not limit the present invention unless otherwise specified. In the present specification and drawings, elements having substantially the same function and configuration are denoted by the same reference numerals to omit redundant description, and elements not directly related to the present invention are not shown.

[0016] FIG. 1 is a diagram showing the overall configuration of a collaborative robot system 100 according to an embodiment of the present invention. The collaborative robot system 100 is an industrial robot system that shares a working area with an operator H, and includes a collaborative robot 110 and a control device 150.

[0017] The collaborative robot 110 is operationally controlled by the control device 150 and operates in either a non-collaborative mode (so-called normal mode) without monitoring by a safety function or a collaborative mode in which it operates in cooperation with the operator H.

[0018] The collaborative robot 110 shown in FIG. 1 is a six-axis articulated robot, and includes a swivel frame 112, a first arm's multiple arms 114 and a second arm 116, and an end effector 118. The end effector 118 is, for example, a hand or a gripper that grips an object to be gripped, and is attached to the tip of the second arm 116.

[0019] The swivel frame 112 is connected to the pedestal 102 so as to be swivellable in a horizontal plane (a plane parallel to the floor, etc.) (first axis). The first arm 114 is connected to the swivel frame 112 so as to be rotatable in a direction perpendicular thereto (second axis). The second arm 116 is connected to the first arm 114 so as to be rotatable in a direction perpendicular thereto (third axis).

[0020] The second arm 116 is divided into an arm tip portion 116a, an arm front portion 116b, and an arm rear portion 116c. The arm front portion 116b is rotatably connected to the arm rear portion 116c (fourth axis). The arm tip portion 116a is rotatably connected to the arm front portion 116b (fifth axis). The end effector 118 is rotatably connected to the second arm 116 (strictly speaking, the arm tip portion 116a) (sixth axis).

[0021] Contact sensors 120a, 120b, 120c, 120d, 120e, 120f for detecting contact of an object with the collaborative robot 110 including a plurality of arms are provided on the first axis to the sixth axis described above, respectively. Hereinafter, when the contact sensors 120a - 120f are not particularly distinguished, they are simply referred to as the contact sensor 120.

[0022] In the present embodiment, a torque sensor is used as the contact sensor 120. Thereby, when an unexpected fluctuation in the torque value occurs in the contact sensor 120, contact of an object with the collaborative robot 110 including the arm is detected. Note that, in the present embodiment, a configuration using a torque sensor as the contact sensor 120 is illustrated, but the present invention is not limited thereto. As the contact sensor 120, for example, other known sensors such as a pressure sensor or a capacitance sensor can be used.

[0023] As shown in FIG. 1, the collaborative robot system 100 of the present embodiment has a lamp 130 that displays the collaborative / non-collaborative operation mode of the collaborative robot 110. The lamp 130 is installed on the second arm 116 (arm rear part 116c), and an operator can visually recognize whether the collaborative robot 110 is operating in either the non-collaborative mode or the collaborative mode by the lamp lighting up and turning off.

[0024] In the present embodiment, a configuration in which the lamp 130 is installed on the second arm 116 (arm rear part 116c) is illustrated, but the present invention is not limited thereto. The lamp 130 may be arranged at a position other than the second arm 116 on the collaborative robot 110 or may be provided separately from the collaborative robot 110 as long as it is a position where the operator H can visually recognize it.

[0025] As a feature of the collaborative robot system 100 of the present embodiment, when the contact sensor 120 detects contact while the collaborative robot 110 is in the collaborative mode, the control device 150 stops the operation of the arms (the first arm 114 and the second arm 116) and blinks the lamp 130. Then, when the contact sensor 120 detects contact at a predetermined timing according to the blinking pattern of the lamp 130, the control device 150 restarts the collaborative robot 110.

[0026] (First Embodiment) FIG. 2 is a sequence diagram for explaining a first embodiment of the operation of the collaborative robot system 100 in FIG. 1. The first embodiment is an example that uses both the detection of contact (so-called keydown event) and the detection of non-contact (so-called keyup event). In this embodiment, "the first contact detection when the lamp is on", "the non-contact detection when the lamp is turned off next", and "the second contact detection when the lamp is on next" are used as the restart conditions.

[0027] As shown in FIG. 2, first, it is assumed that the collaborative robot 110 is operating in the collaborative mode (S202). At this time, the lamp 130 is in the lit state (S204).

[0028] When the contact sensor 120 detects contact with an object (e.g., operator H) while the collaborative robot 110 is operating in the collaborative mode (S206), the control device 150 sends a control signal to stop the operation of the collaborative robot 110 (S208), and sends a control signal to make the lamp 130 blink (S210). The blinking state is a state where short lighting and short extinguishing are repeated. As a result, the collaborative robot 110 stops operating (S212), and the lamp 130 enters the blinking state (S214).

[0029] When the lamp 130 is in the blinking state, operator H touches the collaborative robot 110 aiming at the timing when the lamp 130 is lit in the blinking pattern. The contact sensor 120 detects the first contact (S216). When the contact is detected, the control device 150 associates and stores the contact detection (first time) with the state of the lamp at that time (lit) (S218).

[0030] Operator H releases the hand from the collaborative robot 110 aiming at the extinguishing following the previous lighting. The contact sensor 120 detects the non-contact (S220). When the non-contact is detected, the control device 150 associates and stores the non-contact detection with the state of the lamp at that time (extinguished) (S222).

[0031] Furthermore, operator H touches the collaborative robot 110 again aiming at the lighting following the previous extinguishing. The contact sensor 120 detects the second contact (S224). When the contact is detected, the control device 150 associates and stores the contact detection (second time) with the state of the lamp at that time (lit).

[0032] When the conditions of "first contact detection at lighting", "non-contact detection at the next extinguishing", and "second contact detection at the next lighting" are met as described above, the control device 150 determines that the restart condition is satisfied, and sends a control signal to start restarting to the collaborative robot 110 (S228). In parallel with this, the control device 150 sends a control signal to make the lamp 130 in the lit state to the lamp 130 (S230). As a result, the collaborative robot 110 restarts (S229), operates in the collaborative mode (S232), and the lamp 130 enters the lit state (S234).

[0033] As described above, according to the collaborative robot system 100 of the present embodiment, the control device 150 restarts the collaborative robot 110 triggered by detecting contact and non-contact at a predetermined timing with respect to the blinking pattern of the lamp 130. In other words, restart is performed only when touching rhythmically in accordance with the tempo of the blinking of the lamp 130. Thereby, it is possible to prevent a restart triggered by an operator accidentally touching the collaborative robot 110 while the collaborative robot 110 is stopped. Therefore, the collaborative robot 110 whose operation has been stopped due to contact with an object including the operator can be visually confirmed by the operator looking at the lamp for the operating state of the collaborative robot 110, and can be restarted only when based on the intention of the operator, and the safety of the collaborative robot system 100 can be further improved.

[0034] (Second Embodiment) FIG. 3 is a sequence diagram for explaining a second embodiment of the operation of the collaborative robot system 100 of FIG. 1. Regarding the operations common to the first embodiment, the description will be omitted by attaching the same reference numerals.

[0035] The operations of the collaborative robot system 100 of the first embodiment and the operations of the collaborative robot system 100 of the second embodiment differ in the restart conditions. The second embodiment is an example that uses only the detection of contact (so-called keydown event). In this embodiment, "the first contact detection at the time of lighting", "the second contact detection at the next lighting", and "the third contact detection at the further next lighting" are used as the restart conditions.

[0036] As shown in FIG. 3, when the lamp 130 is in a blinking state, the operator H touches the collaborative robot 110 aiming at the timing when the lamp 130 is lit in the blinking pattern. When the contact sensor 120 detects the first contact (S216), the control device 150 associates and stores the contact detection (first time) and the state of the lamp (lit) at that time (S218).

[0037] Operator H touches the collaborative robot 110 aiming at the next lighting after the lighting touched earlier. The contact sensor 120 detects the second contact (S240). When the second contact is detected, the control device 150 associates and stores the contact detection (second time) with the state of the lamp (lit) at that time (S242).

[0038] Furthermore, operator H touches the collaborative robot 110 aiming at the next lighting after the lighting touched earlier. The contact sensor 120 detects the third contact (S244). When the third contact is detected, the control device 150 associates and stores the contact detection (third time) with the state of the lamp (lit) at that time (S246).

[0039] As described above, when the conditions of "first contact detection at lighting", "second contact detection at the next lighting", and "third contact detection at the next lighting" are met, the control device 150 determines that the restart condition is satisfied, and transmits a control signal for starting the restart to the collaborative robot 110 (S228), and transmits a control signal for setting the lighting state to the lamp 130 (S230). In this way, by using "detecting multiple contacts at a predetermined timing (without using non-contact detection)" as a trigger for restart, the same effects as in the first embodiment can be obtained.

[0040] In the first embodiment, the case where two contact detections and one non-contact detection are used as restart conditions, and in the second embodiment, the case where three contact detections are used as restart conditions is illustrated, but the present invention is not limited thereto. The number of contacts, the number of non-contacts, and the state of the lamp 130 (lit or extinguished) at the time of contact and non-contact can be changed as appropriate.

[0041] In this embodiment, lighting or extinguishing (i.e., blinking) is exemplified as the state of the lamp 130 during contact and non-contact, but the present invention is not limited thereto. As another example, if the lamp 130 emits light in a plurality of colors or includes two or more light bulbs that emit different colors, the collaborative robot 110 can be restarted by contacting and non-contacting in accordance with a predetermined lighting pattern that combines lighting of a predetermined color (e.g., red) of the lamp 130 and lighting of a color different from the predetermined color (e.g., green).

[0042] As described above, the preferred embodiments of the present invention have been described with reference to the accompanying drawings. Needless to say, the present invention is not limited to such examples. It is obvious that those skilled in the art can conceive of various modification examples or correction examples within the scope described in the claims, and it is naturally understood that they also belong to the technical scope of the present invention.

Industrial Applicability

[0043] The present invention is applicable to a collaborative robot system including a collaborative robot that operates in either a non-collaborative mode or a collaborative mode.

Explanation of Signs

[0044] 100... Collaborative robot system, 102... Pedestal, 110... Collaborative robot, 112... Swivel frame, 114... First arm, 116... Second arm, 116a... Arm tip, 116b... Arm front part, 116c... Arm rear part, 118... End effector, 120... Contact sensor, 120a... Contact sensor, 120b... Contact sensor, 120c... Contact sensor, 120d... Contact sensor, 120e... Contact sensor, 120f... Contact sensor, 130... Lamp, 150... Control device, H... Operator

Claims

1. A collaborative robot having an arm and operating in either a collaborative mode or a non - collaborative mode of operation, A contact sensor for detecting that an object has come into contact with the arm, A lamp for displaying the operation mode of the collaborative robot, A control device for controlling the operation of the entire collaborative robot, Comprising, The control device, When the contact sensor detects contact during the collaborative mode, stops the operation of the arm and blinks the lamp, A collaborative robot system, characterized in that when the contact sensor detects contact at a predetermined timing according to the blinking pattern of the lamp, the collaborative robot is restarted.

2. The collaborative robot system according to claim 1, characterized in that when the contact sensor detects contact at the predetermined timing a plurality of times, the control device restarts the collaborative robot.

3. The collaborative robot system according to claim 1, characterized in that when the contact sensor detects contact during lighting in the blinking pattern and non - contact during extinguishing after that lighting is repeated two or more times, the control device restarts the collaborative robot.

4. A collaborative robot having an arm and operating in either a collaborative mode or a non - collaborative mode of operation, A contact sensor for detecting that an object has come into contact with the arm, A lamp for displaying the operation mode of the collaborative robot, A control device for controlling the operation of the entire collaborative robot, Comprising, The control device, When the contact sensor detects contact during the collaborative mode, stops the operation of the arm and lights the lamp in a predetermined lighting pattern with a predetermined color and a color different from the predetermined color, A collaborative robot system, characterized in that when the contact sensor detects contact at a predetermined timing according to the lighting pattern of the lamp, the collaborative robot is restarted.

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