Robot control device, robot control system, and robot control method

Abstract

This invention provides a robot control device, a robot control system, and a robot control method. Even when a worker performs actions unrelated to their assigned task, the robot can still move without interference between the worker and the robot. The robot control device controls a robot that shares a work area with a worker. It includes: an interval estimation unit that calculates the worker's reach range based on the worker's position and body information, and calculates the interval between the reach range and the robot based on the robot's position, shape, and reach range; an interference probability calculation unit that calculates the interference probability between the robot and the worker based on the interval; and a motion control unit that controls the robot's movements based on the interference probability.

Description

Technical Field

[0001] This invention relates to robot control devices, robot control systems, and robot control methods for controlling robots, and particularly to robot control devices, robot control systems, and robot control methods for controlling robots that share a work area with workers to perform actions. Background Technology

[0002] Currently, in fields such as industrial robots, robots and operators share work areas to improve production and assembly efficiency.

[0003] At this point, it is undesirable for the robot to interfere with the operator, thereby causing contact between the robot and the operator in the work area. A technique for preventing such interference is known (e.g., see Patent Document 1).

[0004] Patent Document 1 describes "a robot control device that controls a robot that shares a work area with an operator to perform actions, the operator performing one or more pre-set work processes, the robot control device comprising: a robot control state measurement unit that measures the position and posture of the robot, i.e., the robot control state; a work area setting unit that stores for each work process the following area, which includes the space occupied by the operator's body during the operator's actions from the beginning to the end of the work process, and sets a work area corresponding to the operator's current work process based on a work process designation signal for designating the work process currently being performed by the operator; and a robot instruction generation unit that generates action instructions for the robot based on the work area and the robot control state, and the robot instruction generation unit changes the action instructions for the robot depending on whether the robot is present in the work area."

[0005] When robots and workers share a work area, workers may perform actions unrelated to the work, such as unintentionally extending their arms. Considering this situation, we need a technology to prevent interference between robots and workers.

[0006] International Open Booklet No. 2017 / 203937 Summary of the Invention

[0007] (1) A robot control device of one aspect of this disclosure (e.g., robot control device 100 described later) controls a robot that shares a work area with an operator to perform actions. The robot control device includes:

[0008] The interval estimation unit (e.g., the interval estimation unit 102 described later) calculates the reach range of the operator based on the operator's position information and body information, and calculates the interval between the reach range and the robot based on the robot's position information, shape information, and the reach range.

[0009] An interference probability calculation unit (e.g., interference probability calculation unit 103 described later) calculates the interference probability between the robot and the operator based on the aforementioned interval; and

[0010] The motion control unit (e.g., motion control unit 104 described later) controls the robot's motion based on the aforementioned interference probability.

[0011] (2) In the robot control device described in (1) above, the motion control unit determines the speed of the robot's mechanical arm based on the interference probability.

[0012] (3) In the robot control device described in (2) above, the motion control unit determines the speed of the robot's mechanical arm based on the direction of movement of the robot's mechanical arm.

[0013] (4) In any of the robot control devices described in (1) to (3) above, barcodes or QR codes (registered trademarks) (e.g., QR codes 420 and 210 described later) are respectively installed on the operator and the robot.

[0014] The barcode or QR code installed on the aforementioned operator (e.g., QR code 420 described later) contains the operator's ID and information indicating the operator's physique, and the barcode or QR code installed on the aforementioned robot (e.g., QR code 210 described later) contains the robot's ID and information indicating the robot's size.

[0015] (5) The robot control system of one aspect of the present disclosure includes a robot control device as described in any one of (1) to (4) above, a robot controlled by the robot control device, and a camera for photographing the operator and the robot.

[0016] (6) One aspect of the robot control method disclosed herein is a robot control method using a robot control device (e.g., robot control device 100 described later), which controls a robot that performs actions in a work area shared with an operator.

[0017] Based on the location and body information of the operator, the reach range of the operator is determined. Based on the location and shape information of the robot and the reach range, the interval between the reach range and the robot is determined. Based on the interval, the interference probability between the robot and the operator is determined. Based on the interference probability, the robot's actions are controlled.

[0018] According to one aspect of this disclosure, even if the operator performs actions unrelated to the operation, the robot can still move without causing interference between the operator and the robot. Attached Figure Description

[0019] Figure 1 This is a schematic diagram showing the overall structure of a robot control system according to an embodiment of the present invention.

[0020] Figure 2 Functional blocks representing the robot control device according to embodiments of the present invention.

[0021] Figure 3 This indicates the positional relationship and interval between the operator and the robot.

[0022] Figure 4 This is a flowchart illustrating the actions of the robot's control device.

[0023] Figure 5 This section presents an example of an operational project that utilizes a robot control system.

[0024] Explanation of reference numerals in the attached figures

[0025] 10: Robot control system; 100: Robot control device; 101: Information acquisition unit; 102: Interval estimation unit; 103: Interference probability calculation unit; 104: Motion control unit; 200: Robot; 300: Camera; 400: Operator; 501, 502, 503: Workbench. Detailed Implementation

[0026] <Overall Structure of the Implementation Method>

[0027] First, refer to Figure 1 The overall structure of the robot control system 10 in this embodiment is explained. For example... Figure 1 As shown, the robot control system 10 includes a robot control device 100, a robot 200, and a camera 300. Additionally, the figure shows a worker 400 and a workbench 501. The worker 400 is wearing a work helmet (also known as a safety helmet) with a QR code (registered trademark) 420 attached to the top of their head.

[0028] The robot control device 100 and the robot 200 can be communicatively connected to each other. Additionally, the robot control device 100 and the camera 300 can also be communicatively connected to each other. These connections can be wired connections via signal lines or wireless connections. Alternatively, they can be connections via networks such as LANs (Local Area Networks) or the Internet.

[0029] The robot control device 100 communicates with the robot 200 and the camera 300 through this connection.

[0030] The robot control device 100 is a device used to control the movements of the robot 200. The robot control device 100 includes various function blocks for controlling the movements of the robot 200. See below. Figure 4 This functional block is described in detail. The robot control device 100 can be implemented by adding functions unique to this embodiment to a general robot control device (robot controller).

[0031] Robot 200 is a robot that operates under the control of robot control device 100. Robot 200 includes movable parts such as a robotic arm that operates under the control of robot control device 100 and an end effector (e.g., a gripper for grasping workpieces). A QR code (registered trademark) 210 is provided at the front end of the end effector of robot control device 100. Robot 200 is, for example, a general industrial robot used in factories producing automobiles, home appliances, or electronic components.

[0032] Camera 300 is used to photograph the workers and robots around workbench 501. Camera 300 is mounted, for example, on the ceiling, so that when robot 200 and worker 400 are around workbench 501, it can photograph the QR code 210 located at the front end of the end effector of robot 200 and the QR code 420 mounted on the top of the work hat 410. The photographed data is output to robot control device 100. This description uses a single camera 300, but multiple cameras can also be used.

[0033] QR code 210 contains information such as robot ID (e.g., robot identification number) and robot dimensions. The robot dimensions information includes the length and diameter of the robotic arm and end effector.

[0034] QR code 420 contains worker ID (e.g., worker identification number) and worker physique information. The worker's physique information includes shoulder width and the length of both arms, which can be used to calculate the length when arms are outstretched. QR code 420 can also include the length when arms are outstretched as physique information.

[0035] QR codes 210 and 420 can also be barcodes.

[0036] Figure 2 Functional blocks representing the robot control device according to embodiments of the present invention.

[0037] like Figure 2 As shown, the robot control device 100 includes an information acquisition unit 101, an interval estimation unit 102, an interference probability calculation unit 103, and an action control unit 104.

[0038] The information acquisition unit 101 acquires the shooting data including QR code (registered trademark) 210 and QR code 420 from the camera 300 and sends it to the interval estimation unit 102.

[0039] The interval estimation unit 102 uses the captured data to determine the interval d between the reachable range of the robot 200 and the operator 400. The interval can be determined through the following steps (1) to (4).

[0040] (1) The interval estimation unit 102 determines the position of the front end of the end effector of the robot 200 and the position of the top of the work hat of the worker 400 by detecting the position of the quadrilateral QR code 210 and QR code 420 relative to the shooting area of ​​the camera 300.

[0041] (2) The interval estimation unit 102 reads the body information of the worker 400 recorded in the QR code 420, such as shoulder width and the length of the left and right arms, and calculates the length of the worker 400 when both arms are outstretched. Furthermore, the interval estimation unit 102 determines the length of the worker 400 when both arms are outstretched based on the position of the QR code 420 and the length of the worker 400 when both arms are outstretched. Figure 3 The reach range A of the operator 400 is shown. Here, the reach range is defined as the circular area centered on the position of the operator's QR code 420 when the operator 400 opens both arms. However, considering the situation where the operator 400 bends forward and extends their arms, a larger range than the range when the operator 400 opens their arms can also be defined as the reach range. In addition, when the operator 400 is performing the work, the possibility of extending their hands to the back side is usually low, so the reach range can be defined as the semi-circular area of ​​the operator's front side (chest side).

[0042] (3) The interval estimation unit 102 reads the shape information of the robot recorded in the QR code 210, such as the length of the robotic arm and the end effector and the diameter of the robotic arm and the end effector, and calculates the straight line L that passes through the robotic arm and the end effector and is closest to the operator 400 based on the read information and the position of the QR code 210.

[0043] (4) Figure 3 As shown, the interval estimation unit 102 calculates the interval d between the calculated straight line L and the reach range of the hand. This interval d is the interval between the reach range and the robot.

[0044] The interval estimation unit 102 sends the calculated interval d to the interference probability calculation unit 103.

[0045] The interference probability calculation unit 103 uses an interval d to calculate the interference probability between the robot 200 and the operator 400. Here, the interference probability is calculated based on the overlap between the operator's reach range and the robotic arm of the robot 200, as follows.

[0046] When the distance d between the circular reachable range determined by the operator 400 and the robotic arm of the robot 200 is greater than a threshold Th, the interference probability calculation unit 103 sets the interference probability to 0%. When the distance d is less than the threshold Th but greater than 0, the interference probability calculation unit 103 sets the interference probability to 50%. When the distance d is less than or equal to 0 (overlap), the interference probability calculation unit 103 sets the interference probability to 100%.

[0047] The interference probability calculation unit 103 sends the calculated interference probability to the motion control unit 104.

[0048] The motion control unit 104 controls the movements of the robotic arm and end effector of the robot 200 according to the control program. When the interference probability is 0, the motion control unit 104 controls the robotic arm of the robot 200 to move at a speed (normal speed) set by the control program. When the interference probability is 100%, the motion control unit 104 controls the robotic arm of the robot 200 to stop. When the interference probability is 50%, the motion control unit 104 controls the robotic arm of the robot 200 to move at, for example, about 20% of the normal speed.

[0049] Here, the interference probability is divided into three stages. However, when the interval d is smaller than the threshold Th but larger than 0, the interference probability can be set to multiple values, such as 10%, 30%, 50%, and 70%, based on the value of the interval d. The speed of the robotic arm is then controlled in stages based on these interference probability values.

[0050] In addition, preferably when the probability of interference between the robot 200 and the operator 400 is 100%, the motion control unit 104 controls the robot 200's robotic arm to move to a location where the probability of interference is less than 50% and then stops. If interference with the operator is avoided, the robot 200's robotic arm returns to its original position.

[0051] The motion control unit 104 controls the speed of the robotic arm based on the direction of movement of the robotic arm controlled by the control program. For example, when the probability of interference is 100%, the motion control unit 104 controls the robotic arm of the robot 200 to stop when the robotic arm approaches the operator 400, but when the robotic arm moves away from the operator 400, the motion control unit 104 controls the robotic arm of the robot 200 to move at a normal speed.

[0052] The direction of movement of the robotic arm of robot 200 can be determined based on the control program. However, the direction of movement of the robotic arm can also be determined by the change in interval d and whether the change is in the direction of increasing or decreasing.

[0053] Reference Figure 4 The following flowchart illustrates the operation of the robot control device 100. Here, it is shown that the robotic arm of the robot 200 moves to approach the operator 400.

[0054] In step S11, the information acquisition unit 101 acquires shooting data including QR code (registered trademark) 210 and QR code 420 from the camera 300.

[0055] In step S12, the interval estimation unit 102 uses the captured data to determine the interval d between the reach range of the robot 200 and the operator 400.

[0056] In step S13, the interference probability calculation unit 103 calculates the interference probability based on the interval d. Next, in step S14, the value of the interference probability is determined. When the interference probability is 0%, in step S15, the motion control unit 104 controls the robot 200 to move at a normal speed. When the interference probability is 50%, in step S16, the motion control unit 104 controls the robot 200 to move at approximately 20% of its normal speed. When the interference probability is 100%, in step S17, the motion control unit 104 controls the robot 200 to stop.

[0057] In step S18, the motion control unit 104 determines whether the control program has ended. If it has not ended, it returns to step S11. The motion control unit 104 terminates the process when the control program ends.

[0058] The actions of the robot control device 100 described above can prevent interference between the operator 400 and the robot 200. That is, when the operator 400 is working on the workbench 501, the robotic arm of the robot 200 can be prevented from entering the workbench 501.

[0059] The above explanation is an example of preventing interference between the operator 400 and the robot 200, but it can also be applied to situations where someone other than the operator 400, such as a manager, approaches the robot 200 while wearing a work hat with a QR code attached to the top of their head.

[0060] The above describes the functional blocks and actions included in the robot control device 100.

[0061] To implement the functional blocks of the robot control device 100, the robot control device 100 includes a computing and processing unit such as a CPU (Central Processing Unit). In addition, the robot control device 100 also includes auxiliary storage devices such as HDDs (Hard Disk Drives) that store various control programs such as application software and OS (Operating System), and main storage devices such as RAMs (Random Access Memory) that store data temporarily needed when the computing and processing unit executes programs.

[0062] Furthermore, in the robot control device 100, the arithmetic processing unit reads application software and operating system from the auxiliary storage device, expands the read application software and operating system in the main storage device, and performs arithmetic processing based on these application software and operating system. Additionally, it controls various hardware components of each device based on the results of this processing. Thus, the functional blocks of this embodiment are implemented. In other words, this embodiment can be implemented through the cooperation of hardware and software.

[0063] <Examples of Operational Projects>

[0064] use Figure 5This describes an example of a work process using the robot control system 10. Robot 200 uses a robotic arm to move an unfinished product 601 from workbench 502 to workbench 501, and then moves the robotic arm to the side of workbench 502 to move the next unfinished product 602. At this time, worker 400 is facing workbench 503 and is not near workbench 501. Worker 400 moves from workbench 503 to workbench 501, installs two parts on the unfinished product 601 placed on workbench 501, and then moves to the next workbench 503. Then, worker 400 uses an inspection device at workbench 503 to inspect the unfinished product 601 with the two parts installed. While worker 400 is inspecting at workbench 503, robot 200 uses its robotic arm to move the unfinished product 602 from workbench 502 to workbench 501.

[0065] In the above operation process, when robot 200 transports unfinished product 601 to workbench 501, operator 400 is not near workbench 501, so the probability of interference between robot 200 and operator 400 is 0%. When robot 200's robotic arm places unfinished product 601 on workbench 501 and moves to the side of workbench 502, the probability of interference is still 0 even if operator 400 is near workbench 501.

[0066] However, when robot 200 uses its robotic arm to transport unfinished product 602 from workbench 502 to workbench 501, if operator 400 is installing two parts on unfinished product 601 on workbench 501, interference may occur between operator 400 and robot 200.

[0067] The robot control device 100 reduces the speed of the robotic arm of the robot 200 to 20% of the normal speed when the interference probability is 50%, and stops the robotic arm of the robot 200 when the interval d becomes 0 and the interference probability becomes 100%, or before the interference probability becomes 100%, thereby preventing interference.

[0068] Subsequently, when operator 400 moves the unfinished product 601 (product) with two parts installed to workbench 503, robot control device 100 controls the robot 200 to transport the unfinished product 602 to workbench 501 when the interference probability is 0%.

[0069] Thus, in order to avoid interference between the robot 200 and the operator 400, the robot control device 100 of this embodiment calculates the interference probability between the robot 200 and the operator 400 to control the robot 200.

[0070] Furthermore, the aforementioned robot control device can be implemented using hardware, software, or a combination thereof. Additionally, the robot control method, which involves the cooperation of various devices included in the aforementioned robot control system, can also be implemented using hardware, software, or a combination thereof. Here, implementation using software means implementing it by reading and executing a program into a computer.

[0071] Programs can be stored and provided to a computer using various types of non-transitory computer-readable media. Non-transitory computer-readable media include various types of tangible storage media. Examples of non-transitory computer-readable media include magnetic recording media (e.g., floppy disks, hard disk drives), optical-magnetic recording media (e.g., optical discs), CD-ROMs (Read Only Memory), CD-Rs, CD-R / Ws, and semiconductor memories (e.g., mask ROMs, PROMs (Programmable ROMs), EPROMs (Erasable PROMs), flash memory ROMs, and RAMs (Random Access Memory)). Additionally, programs can be provided to a computer using various types of transient computer-readable media.

[0072] Furthermore, the above-described embodiments are preferred embodiments of the present invention, but the scope of the present invention is not limited to the above-described embodiments, and it can be implemented in various modified ways without departing from the spirit of the present invention. For example, as a variation, the following modifications can be implemented.

[0073] <Variation Example 1>

[0074] In the above embodiment, the robot control device 100 controls the movement of the robot 200 based on the captured data including QR code (registered trademark) 210 and QR code 420 obtained by the camera 300. QR code 420 contains information such as the operator's ID and the operator's physique, while QR code 210 contains information such as the robot's ID and robot dimensions. These can be modified so that QR code 420 contains only the operator's ID and QR code 210 contains only the robot's ID. In this case, the interval estimation unit 102 records information such as the operator's physique corresponding to the operator's ID and information such as the robot's dimensions corresponding to the robot's ID in advance. Thus, the interval estimation unit 102 can calculate the interval d.

[0075] <Variation Example 2>

[0076] In the above embodiments, it is assumed that the robot control device 100 and the robot 200 are implemented by different devices. This can be modified so that the robot control device 100 and the robot 200 are implemented by the same device. Alternatively, part or all of the functional blocks of the robot control device 100 can be implemented by a device that is part of the same device as the robot 200.

[0077] <Variation Example 3>

[0078] In the above embodiment, it is assumed that the robot 200 and the operator 400 have a one-to-one relationship. This embodiment can be modified to apply the relationship between the robot 200 and the operator 400 to one-to-many, many-to-one, or many-to-many.

Claims

1. A robot control device for controlling a robot that shares a work area with an operator to perform actions, characterized in that, have: The interval estimation unit calculates the reach range of the operator based on the operator's position information and body information, and calculates the interval between the reach range and the robot based on the robot's position information, shape information, and reach range. The interference probability calculation unit calculates the interference probability between the robot and the operator based on the aforementioned interval; and The motion control unit controls the robot's movements based on the aforementioned interference probability. The first barcode or first QR code is installed by the aforementioned workers, and the second barcode or second QR code is installed on the aforementioned robot. The first barcode or first QR code contains the worker's ID, or the worker's ID combined with the aforementioned physical information. The robot ID, or the robot ID and the aforementioned shape information, are recorded in the second barcode or second QR code. The aforementioned interval estimation unit obtains the first barcode or first QR code, the second barcode or second QR code, the position of the first barcode or first QR code, and the position of the second barcode or second QR code based on the shooting data from the cameras that photographed the aforementioned workers and the aforementioned robot. The aforementioned interval estimation unit calculates the length of the worker's outstretched arms based on the position of the first barcode or first QR code and the body information recorded in the first barcode or first QR code or obtained using the worker's ID. It then determines the circular area centered on the position of the first barcode or first QR code installed on the worker, extending outwards when the worker's arms are open, and uses this as the worker's reach range. The aforementioned interval estimation unit calculates the straight line passing through the side of the robot's robotic arm closest to the operator, based on the position of the second barcode or the second QR code, and the shape information recorded in the second barcode or the second QR code, or the shape information obtained using the robot ID. The aforementioned interval estimation unit calculates the interval between the aforementioned reach range and the aforementioned robot based on the aforementioned reach range and the aforementioned straight line. When the interference probability calculated by the interference probability calculation unit based on the distance between the arrival range and the robot calculated by the distance estimation unit is 100%, the motion control unit controls the robot's robotic arm to move to a location where the interference probability is less than 50% and then stops.

2. The robot control device according to claim 1, characterized in that, The motion control unit determines the speed of the robot's robotic arm based on the aforementioned interference probability.

3. The robot control device according to claim 2, characterized in that, The motion control unit determines the speed of the robot's robotic arm based on the direction of movement of the robotic arm.

4. A robot control system, characterized in that, have: The robot control device according to any one of claims 1 to 3; A robot controlled by the robot control device; and The camera that photographs the workers and the aforementioned robot.

5. A robot control method for a robot control device, wherein the robot control device controls a robot that shares a work area with an operator to perform actions, characterized in that, Based on the location and physical information of the aforementioned workers, the reach range of the aforementioned workers can be determined. Based on the robot's location and shape information, as well as the aforementioned reachable range, the interval between the reachable range and the robot is calculated. The interference probability between the robot and the operator is calculated based on the above intervals. The robot's actions are controlled based on the aforementioned interference probabilities. The first barcode or first QR code is installed by the aforementioned workers, and the second barcode or second QR code is installed on the aforementioned robot. The first barcode or first QR code contains the worker's ID, or the worker's ID combined with the aforementioned physical information. The robot ID, or the robot ID and the aforementioned shape information, are recorded in the second barcode or second QR code. Based on the camera data captured by the cameras that photographed the aforementioned workers and the aforementioned robot, the first barcode or first QR code, the second barcode or second QR code, the position of the first barcode or first QR code, and the position of the second barcode or second QR code are obtained. Based on the location of the first barcode or first QR code, and the body information recorded in the first barcode or first QR code or obtained using the worker ID, the length of the worker's arms when outstretched is calculated. The circular area centered on the location of the first barcode or first QR code installed on the worker, where the worker's arms are outstretched, is then used as the reachable range. Based on the position of the second barcode or second QR code, and the shape information recorded in the second barcode or second QR code, or the shape information obtained using the robot ID, a straight line passing through the side of the robot's robotic arm closest to the operator is calculated. Based on the aforementioned reach range and the aforementioned straight line, the aforementioned distance between the aforementioned reach range and the aforementioned robot is calculated. When the interference probability calculated based on the above-mentioned reach range and the above-mentioned interval of the robot is 100%, control is performed so that the robot's robotic arm moves to a location where the interference probability is less than 50% and stops.

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