ROBOT SYSTEM SIMULATION DEVICE

Abstract

A simulation device (1) for a robot system, comprising at least one robot, at least one sensor for detecting a moving body in a detection area around the robot, and at least one control device for controlling the robot, wherein a control device corresponding to a sensor slows down or stops an operation of a robot when the sensor detects the moving body, and wherein the simulation device (1) for the robot system additionally comprises at least one processor (4), at least one memory (3), and an input device (2), wherein the memory (3) serves to store layout information about the robot system,the input device (2) receives inputs of motion information relating to the moving body, and the processor (4) performs a simulation of an operation of the robot system based on the layout information and the motion information and calculates the delay time of the operation with respect to a case where no moving body is detected in the detection area.

Description

{Technical field}

[0001] The present disclosure relates to a simulation device for a robot system. {State of the art}

[0002] There is a robot system that performs control in such a way that the operation of a robot is slowed down or stopped when the personnel working with it approach the operating robot within a shorter distance than the specified distance.

[0003] In addition, there is a simulation device for such a robot system that simulates the operation of a robot and personnel working with it in order to shorten the time during which the robot is slowed down or stopped (see, for example, Patent Literature 1). {List of citations}{Patent literature}

[0004] {PTL 1] Unexamined Japanese Patent Application, Publication No. 2017-24113 {Summary of the invention}{Technical problem}

[0005] However, there is generally a case where a moving body, such as an automated guided vehicle performing a different task than the robot system, enters or remains within the robot's operating range. In this case, the moving body is also detected by a sensor, causing the robot's operation to slow down or stop, and increasing the robot system's cycle time.

[0006] Therefore, it is desirable to keep the cycle time of the robot system within a desired time even if a moving body other than the originally arranged moving body, such as personnel working with it, is within the operating range of the robot. {Solution to the problem}

[0007] One aspect of the present disclosure is a simulation device for a robot system including at least one robot, at least one sensor for detecting a moving body in a detection area around the robot, and at least one control device for controlling the robot, wherein the control device corresponding to the sensor slows down or stops an operation of the robot in response to the sensor detecting the moving body, the simulation device including at least one processor, at least one memory, and an input device, wherein: the memory stores layout information about the robot system; the input device receives inputs of motion information about the moving body;and the processor performs a simulation of an operation of the robot system based on the layout information and the motion information and calculates a delay time of the operation with respect to a case where the moving body is not detected in the detection area.; {Brief description of the drawings} { Fig. 1] Fig. 1 is a plan view showing a layout for a robot system to which a simulation device according to an embodiment of the present disclosure is applied. { Fig. 2] Fig. 2 is a block diagram showing the simulation apparatus according to the embodiment of the present disclosure. { Fig. 3] Fig. 3 is a flowchart for explaining a simulation method using the simulation device in Fig. 2. { Fig. 4] Fig. 4 is a timing chart showing the operation of a robot in a case where there is no moving body in the photographing area of ​​the robot system in Fig. 1 is present. { Fig. 5] Fig. 5 is a timing diagram incorporated in the simulation device in Fig. 2 shows entered movement information. { Fig. 6] Fig. 6 is a timing chart showing the operation of the robot considering the entry of a moving body into the photographing area in the robot system in Fig. 1 shows. { Fig. 7] Fig. 7 is a plan view showing a modification of the layout of the robot system in Fig. 1 shows. {Description of the embodiment}

[0008] Hereinafter, a simulation device 1 for a robot system 10 according to an embodiment of the present disclosure will be described with reference to the drawings.

[0009] First, the robot system 10 to which the simulation device 1 of this embodiment is applied will be described.

[0010] As in Fig. 1, the robot system 10 includes: at least one robot 20; at least one camera (sensor) 31, 32 for photographing the periphery of the robot 20; and at least one control device 40. In Fig. 1, a part of the robot system 10 is shown to simplify the description, and a robot 20, two cameras 31, 32 and a control device 40 provided in the robot system 10 are shown.

[0011] The robot 20 is, for example, a six-axis articulated robot. The robot 20 is installed between two worktables WT1, WT2 arranged so as to be spaced apart in the horizontal direction. In addition, the robot 20 performs, for example, a task of successively picking up a plurality of workpieces W randomly stacked on the worktable WT1 and moving the workpieces W to the worktable WT2.

[0012] For example, cameras 31, 32 are two-dimensional cameras that capture two-dimensional images. Furthermore, cameras 31, 32 are installed above work tables WT1, WT2, facing downwards, and each have conical photographing areas (detection areas) s1, s2 at positions including work tables WT1, WT2. With this configuration, cameras 31, 32 can capture two-dimensional images of the photographing areas s1, s2 at a predetermined frame rate.

[0013] The control device 40 includes at least a processor (not shown) and a memory (not shown), such as a RAM and a ROM, and is connected to the robot 20 and the cameras 31, 32.

[0014] An operation program for operating the robot 20 is stored in the memory of the control device 40. Furthermore, the processor of the control device 40 executes the operation program stored in the memory to operate each axis of the robot 20, thereby causing the robot 20 to perform a desired task.

[0015] Furthermore, the control device 40 transmits a photography command to one of the cameras 31, 32 corresponding to the orientation of the robot 20, causing the camera 31, 32 to perform photography at a predetermined frame rate. In other words, the control device 40 causes the camera 31, 32 on the side toward which a wrist of the robot 20 is directed to capture a two-dimensional image and receives the two-dimensional image.

[0016] Furthermore, the control device 40 performs image processing on the received two-dimensional image to extract all the moving bodies included in the two-dimensional image. Then, the control device 40 excludes the robot 20 (including a tool or the like attached to the robot 20) from the extracted moving bodies and determines whether or not a moving body A other than the robot 20 is included. In a case where a moving body A other than the robot 20 is included in all of the extracted moving bodies, the control device 40 slows down or stops the operation of each axis of the robot 20. In other words, the cycle time of the robot system 10 is delayed by the time during which the operation of the robot 20 is slowed down or stopped.

[0017] Next, the simulation device 1 according to the embodiment of the present disclosure will be described with reference to the drawings.

[0018] The simulation device 1 according to this embodiment is implemented by a computer such as a personal computer.

[0019] As in Fig. 2, the simulation device 1 includes, for example, an input device 2, a memory 3 such as a ROM and a RAM, at least one processor 4 such as a CPU, and a display device 5.

[0020] The input device 2 is composed of, for example, a keyboard, a touch panel, a control panel, a serial interface such as a USB, etc. Furthermore, the input device 2 receives motion information about at least one moving body A input by an operator operating the simulation device 1. The motion information is, for example, information including a trajectory of the moving body A and time at each position in the trajectory based on the operation program start time for the robot system 10.

[0021] The memory 3 stores layout information about the robot system 10 in a factory. The layout information includes, for example, information relating to the positions and sizes of the individual components of the robot system 10, the work tables WT1, WT2, and the photography areas s1, s2, as well as information relating to the position, shape, etc. of a passage P near the robot 20. All of this layout information is modeled three-dimensionally and stored in the memory 3.

[0022] In addition, the memory 3 stores a simulation program and an operation program for the robot system 10. When the simulation program is executed by the processor 4, which will be described later, the operation program for the robot system 10 is executed in a virtual space on the computer.

[0023] Furthermore, the memory 3 stores an ideal cycle time of the robot system 10, that is, a cycle time in a case where the moving body A does not enter the photographing area s1, s2 and the operation of the robot 20 is not slowed down or stopped. The memory 3 also stores the motion information about the moving body A input to the input device 2.

[0024] The processor 4 extracts the motion information about the moving body A and the layout information about the robot system 10 stored in the memory 3, and determines whether the motion trajectory of the moving body A overlaps the photographing area s1, s2 or not based on the two pieces of information.

[0025] Furthermore, the processor 4 executes the simulation program stored in the memory 3, whereby the robot system 10 and the passage P are arranged near it, and the moving body A moves along the passage P in the virtual space on the computer. Then, the processor 4 uses the motion information and the layout information taken from the memory 3 to execute the operation program for the robot system 10 arranged in the virtual space and a simulation of the movement of the moving body A.

[0026] Further, the processor 4 calculates a cycle time of the operation program from the simulation result, taking into account an operation delay of the robot 20 caused by the moving body A entering the photographing area s1, s2.

[0027] The display device 5 is formed of a liquid crystal display or the like. Based on the layout information, the processor 4 causes the display device 5 to superimpose the robot system 10 and the layout in its periphery, and the photographing areas s1, s2. Furthermore, the processor 4 causes the display device 5 to display, for example, a delay time calculated by comparing the calculated cycle time of the operation program with the ideal cycle time stored in the memory 3, along with the displayed layout information.

[0028] The operation of the thus configured simulation device 1 according to this embodiment will be described below.

[0029] The following describes a method for simulating the operation of the Fig. 1 shown robot system 10 by way of example using the Fig. 3 shown flowchart.

[0030] First, the operator operating the simulation device 1 inputs the layout information of the robot system 10 into the input device 2 (step S1). As a result, a three-dimensional model showing the passage P near the robot 20 and the relative positional relationship of the individual components of the robot system 10 and the photographing areas s1, s2 with respect to the passage P is stored in the memory 3. Furthermore, the operator inputs the operation program for the robot system 10 and the pre-calculated ideal cycle time of the operation program, along with the layout information, into the input device 2 for storage in the memory 3.

[0031] The Fig. 4 is an exemplary timing chart of the operation program input to the input device 2, in which the robot 20 is caused to perform a desired task by moving the wrist front end of the robot 20 back and forth between the work tables WT1, WT2 at an interval of n seconds.

[0032] Next, the operator inputs the trajectory of each moving body A and the time at each position in the trajectory into the input device 2 as the motion information about all moving bodies A moving in the passage P near the robot 20 (step S2). The inputted motion information is stored in the memory 3.

[0033] In this state, the processor 4 extracts the layout information and the movement information stored in the memory 3 and compares the two pieces of information. Then, the processor 4 determines whether the movement trajectory of the moving body A contained in the movement information overlaps the photographing area s1, s2 contained in the layout information (step S3). In a case where it is determined that the movement trajectory and the photographing area s1, s2 overlap, the processor 4 extracts an overlapping time zone and stores the time zone in the memory 3. In other words, the memory 3 stores, as shown in Fig. 5, the time zones in which the moving body A is located in each photographing area s1, s2 with respect to the elapsed time from the operation program start time for the robot system 10.

[0034] Subsequently, the processor 4 executes the simulation program stored in the memory 3 (step S4).

[0035] When the simulation program is executed, the processor 4 sets up the robot system 10, the passage P, and the moving body A in the virtual space on the computer based on the layout information read from the memory 3. Then, the processor 4 causes the robot system 10 to operate according to the operation program and also causes the moving body A to move based on the motion information in the virtual space.

[0036] In this case, when the robot 20 performs a task with the wrist front end directed toward the side of the work table WT1, for example, the entry of the moving body A into the photographing area s1 causes the robot 20 to stop or decelerate. As shown in the Fig. 4 to 6, therefore, the operation program is delayed by the time during which the operation of the robot 20 is stopped or slowed down while the robot 20 performs the task on the work table WT1 side.

[0037] Similarly, when the robot 20 performs a task with the wrist front end directed toward the worktable WT2 side, the entry of the moving body A into the photographing area s2 causes the robot 20 to stop or decelerate, and the operation program is delayed by the time during which the robot 20 is stopped or decelerated.

[0038] The processor 4 calculates a cycle time of the operation program that is delayed due to the moving body A entering the photographing area s1, s2 (step S5). Further, the processor 4 calculates a delay time of the operation program by comparing the cycle time calculated from the simulation result with the ideal cycle time stored in the memory 3. In this process, a delay time while the robot 20 executes the task on the worktable WT1 side and a delay time while the robot 20 executes the task on the worktable WT2 side are separately calculated.

[0039] Then, the processor 4 causes the display device 5 to display the calculated cycle time and delay time along with the layout information stored in the memory 3 (step S6). For example, the display device 5 displays the respective delay times calculated by the processor 4, which are caused by the entry of the moving body A into the photographing areas s1, s2, in conjunction with the photographing areas s1, s2 displayed based on the layout information.

[0040] Meanwhile, the execution of the simulation program described above is omitted in a case where the processor 4 determines that the movement path of the moving body A and the photographing area s1, s2 do not overlap (step S3). Then, the processor 4 causes the display device 5 to display that the moving body A does not enter the photographing area s1, s2 (step S6).

[0041] As described above, the operator can confirm whether there is a possibility that the cycle time of the robot system 10 is delayed by checking the display device 5. Furthermore, if there is a possibility that the cycle time is delayed, it is possible to confirm the delay time of the operation program for the robot system 10, which is calculated from the simulation result and displayed on the display device 5.

[0042] Therefore, the operator can determine whether the cycle time exceeds a desired time based on the display on the display device 5. Furthermore, in a case where the cycle time exceeds the desired time, it is possible to change the layout of the robot system 10 to reduce the delay time of the operation program.

[0043] In this case, the operator can distinguishably grasp the delay time caused by the moving body A entering the photographing area s1 and the delay time caused by the moving body A entering the photographing area s2 based on the display on the display device 5. Thus, it is possible to prioritize reducing the delay time that has a greater impact on the cycle time among the two delay times and change the layout of the robot system 10 more efficiently.

[0044] For example, if most of the delay of the cycle time is due to the delay time with respect to the photographing area s1 in the robot system 10 in Fig. 1, the entire robot system 10 must be arranged away from the passage P next to the work table WT1.

[0045] It should be noted that, although in this embodiment, the trajectory of the moving body A and the time at each position in the trajectory are input to the input device 2 as the motion information, the motion information is not limited thereto.

[0046] For example, in a case where the number of times the moving body A enters the photographing area s1, s2 per unit time and a stay time per entry have been obtained, this information can be inputted as the movement information to the input device 2.

[0047] In this case, the processor 4 multiplies the number of times the moving body A enters the photographing area s1, s2 by the residence time per entry. The processor 4 calculates the cumulative residence time of the moving body A in the photographing area s1 per unit time and the cumulative residence time of the moving body A in the photographing area s2 per unit time.

[0048] The longer the cumulative residence time, the longer the delay time associated with the cycle time of the operation program can be, and thus it can be estimated that the delay time proportional to the cumulative residence time is generated in each of the photographing areas s1, s2.

[0049] Therefore, the processor 4 can execute a simulation of the operation program and calculate the cycle time taking into account the delay time proportional to the cumulative residence time of the moving body A in each of the photographing areas s1, s2.

[0050] Furthermore, in a case where the frequency with which the moving body A enters the photographing area s1, s2 per unit time and the stay time per entry are obtained as multiple classified stages, these stages can be used as the motion information.

[0051] In a case where the frequency of entry of the moving body A per unit time into the photographing area s1, s2 and the residence time per entry are each classified into five levels, the scores corresponding to the heights of the respective levels are assigned to the respective levels. By multiplying the score assigned to the entry frequency level by the score assigned to the residence time level and calculating the sum, it is possible to estimate the cumulative residence time of the moving body A in each of the photographing areas s1, s2.

[0052] In this embodiment, when the cycle time of the robot system 10 exceeds a desired time, the delay time of the operation program is reduced by changing the layout of the robot system 10. Instead, the delay time can be reduced by changing the operation program for the robot system 10 without changing the layout of the robot system 10. Alternatively, the delay time can be reduced by changing the movement mode of the moving body A moving in the passage P, that is, the movement trajectory, the movement speed, or the like of the moving body A.

[0053] In this case, as in Fig. 6, the display device 5 displays, based on the simulation result, the time zones in which the operation of the robot 20 is stopped according to the time of the operation program.

[0054] With this configuration, the operator can detect the timing at which the operation of the robot 20 is stopped in the executed operation program. Therefore, the operator can change the operation program for the robot system 10 or the movement method of the moving body A so that the moving body A enters the photographing area s1, s2 while avoiding these timings.

[0055] In addition, although the robot system 10 to which the simulation device 1 is applied has the two photographing areas s1, s2 in this embodiment, one photographing area or three or more photographing areas may be provided.

[0056] Furthermore, in this embodiment, the simulation device 1 is applied to the robot system 10 in which the cameras 31, 32 are installed above the work tables WT1, WT2, respectively. As shown in Fig.7, the simulation device 1 can be applied to a robot system 10 provided with a camera (sensor) 33 fixed to the wrist of the robot 20 and having a photographing area (detection area) s3 in the periphery of the wrist front end.

[0057] Furthermore, in this embodiment, the robot system 10 to which the simulation device 1 is applied includes the cameras 31, 32 arranged above the work tables WT1, WT2, respectively. Therefore, the photographing areas s1, s2 extend conically downward from above the work tables WT1, WT2, respectively. In other words, it should be considered that the photographing areas s1, s2 for detecting the moving body A change in the height direction.

[0058] Alternatively, an area sensor or the like in which a plurality of line sensors are arranged side by side may be used as the cameras 31, 32 of the robot system 10 to which the simulation device 1 is applied.

[0059] In this case, the size of the photographing area s1, s2 is constant in the height direction. Thus, the simulation device 1 can determine the overlap between the moving body A and the photographing area s1, s2 two-dimensionally. Therefore, even if the layout information input to the input device 2 is a two-dimensional model, the accuracy of the simulation of the operating program is not affected.

[0060] Although the embodiments of the present disclosure have been described in detail above, the present disclosure is not limited to the individual embodiments described above. In these embodiments, various additions, substitutions, changes, partial omissions, and so on can be made within a range that does not depart from the scope of the invention or within a range that does not depart from the spirit and spirit of the present invention, which is derived from the content recited in the claims and their equivalents. For example, in the embodiments described above, the order of each operation and the order of each process are exemplified, and the orders are not limited thereto.

[0061] With respect to the above-mentioned embodiments and modifications, the following appendices are further disclosed. (Appendix 1)

[0062] A simulation device 1 for a robot system 10, including at least one robot 20, at least one sensor 31, 32, 33 for detecting a moving body in a detection area s1, s2, s3 around the robot 20, and at least one control device 40 for controlling the robot 20, wherein the control device 40 corresponding to the sensor 31, 32 controls an operation of the robot 20 in response to the sensor 31, 32, 33 detecting, decelerating, or stopping the moving body A, the simulation device 1 comprising at least one processor 4, at least one memory 3, and an input device 2, wherein: the memory 3 stores layout information about the robot system 10; the input device 2 receives inputs of motion information about the moving body A;and the processor 4 performs a simulation of an operation of the robot system 10 based on the layout information and the motion information and calculates a delay time of the operation with respect to a case where the moving body A is not detected in the detection area s1, s2, s3.; (Appendix 2)

[0063] The simulation device 1 for the robot system 10 according to Appendix 1, wherein the processor 4 calculates a cycle time of the operation of the robot system 10. (Appendix 3)

[0064] The simulation device 1 for the robot system 10 according to Appendix 1 or 2, wherein the simulation device 1 further comprises a display device 5 for displaying the layout information, wherein the processor 4 causes the display device to display, based on the movement information and the layout information, an area s1, s2, s3 in which the moving body A is detected by the sensor 31, 32, 33, superimposed on the layout information. (Appendix 4)

[0065] The simulation device 1 for the robot system 10 according to any one of Appendices 1 to 3, wherein the motion information includes a motion trajectory of the moving body A and a time at which the moving body A is located at each position in the motion trajectory. (Appendix 5)

[0066] The simulation device 1 for the robot system 10 according to any one of Appendices 1 to 3, wherein the motion information includes a number of times the moving body A enters the detection area s1, s2, s3 per unit time and a residence time per entry. (Appendix 6)

[0067] The simulation device 1 for the robot system 10 according to any one of Appendices 1 to 3, wherein: the motion information includes a number of times the moving body A enters the detection area s1, s2, s3 and a stay time per entry, each classified into a plurality of stages; and the processor 4 estimates the delay time based on a sum value obtained by quantifying the stages respectively. (Appendix 7)

[0068] The simulation device 1 for the robot system 10 according to any one of Appendices 1 to 6, wherein: the processor 4 determines whether or not there is a possibility that the moving body A enters the detection range s1, s2, s3 based on the motion information input to the input device 2; and the processor 4 executes the simulation in response to determining that there is a possibility that the moving body A enters the detection range s1, s2, s3. {Reference symbol list} 1 simulation device 2 input device 3 storage 4 processor 5 Display device 10 Robot system 20 robots 31 Camera (Sensor) 32 Camera (Sensor) 33 Camera (Sensor) 40 Control device A moving body s1 Photography area (detection area) s2 Photography area (detection area) s3 photography area (detection area) QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] JP 2017-24113

[0004]

Claims

[1] A simulation device for a robot system comprising at least one robot, at least one sensor for detecting a moving body in a detection area around the robot, and at least one control device for controlling the robot, wherein the control device corresponding to the sensor slows down or stops an operation of the robot in response to the sensor detecting the moving body, the simulation device comprising at least one processor, at least one memory, and an input device, wherein: the memory stores layout information about the robot system; the input device receives inputs of motion information about the moving body; and the processor executes a simulation of an operation of the robot system based on the layout information and the motion information, and calculates a delay time of the operation with respect to a case where the moving body is not detected in the detection area. [2] The simulation device for the robot system according to claim 1, wherein the processor calculates a cycle time of operation of the robot system. [3] The simulation device for the robot system according to claim 1 or 2, wherein the simulation device further comprises a display device for displaying the layout information, wherein the processor causes the display device to display, based on the movement information and the layout information, an area in which the moving body is detected by the sensor in superposition over the layout information. [4] A simulation device for the robot system according to any one of claims 1 to 3, wherein the motion information includes a motion trajectory of the moving body and a time at which the moving body is located at each position in the motion trajectory. [5] A simulation device for the robot system according to any one of claims 1 to 3, wherein the motion information includes a number of times the moving body enters the detection area per unit time and a stay time per entry. [6] A simulation device for the robot system according to any one of claims 1 to 3, wherein: the movement information includes a number of times the moving body enters the detection area and a residence time per entry, each of which is classified into several levels; and the processor estimates the delay time based on a sum value obtained by quantifying the stages respectively. [7] A simulation device for the robot system according to any one of claims 1 to 6, wherein: the processor determines, based on the movement information input to the input device, whether or not there is a possibility that the moving body enters the detection area; and the processor executes the simulation in response to determining that there is a possibility of the moving body entering the detection area.

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