WO2024024036A1

WO2024024036A1 - Robot parameter setting device

Info

Publication number: WO2024024036A1
Application number: PCT/JP2022/029131
Authority: WO
Inventors: 恭平小窪
Original assignee: ファナック株式会社
Priority date: 2022-07-28
Filing date: 2022-07-28
Publication date: 2024-02-01
Also published as: TW202419238A

Abstract

This robot parameter setting device comprises: a first setting element which is one of an object (60) and a sensor (50) and which is attached to an arm (10a); a second setting element which is the other of the object (60) and the sensor (50); and a control unit which causes the arm (10a) to execute a parameter setting operation for disposing the first setting element at multiple positions. In the first half of the parameter setting operation or prior to the parameter setting operation, the control unit causes the sensor (50) to acquire first check data (23e) concerning the object in a state where the first setting element is being disposed at a setting check position. In the second half of the parameter setting operation or after the parameter setting operation, the control unit disposes the first setting element at the setting check position and also causes the sensor (50) to acquire second check data (23f) concerning the object, and then determines whether or not there has been a positional change on the basis of the two sets of data.

Description

Robot parameter setting device

The present invention relates to a robot parameter setting device.

A device is known that measures the position of the tip of a tool with respect to the tip of a robot arm. Furthermore, a device is known that associates position information in an image obtained by a visual sensor with position information of a robot. Also, a device is known that uses a master work to make a camera coordinate system correspond to a robot coordinate system. Furthermore, a robot system is known in which a robot mounted on a trolley performs work on a fixed target device. In this robot system, a plurality of marks are provided on the target device, and the position of the target device with respect to the robot on the cart is grasped using the plurality of marks as landmarks. For example, please refer to Patent Documents 1 to 4.

Patent No. 4191080 Japanese Patent Application Publication No. 2015-174191 Japanese Patent Application Publication No. 2018-034271 JP2020-163518A

In order for a robot to work on a work object, it is necessary to make a correspondence between the coordinate system of the robot and the coordinate system of the tool at the tip of the robot, and a correspondence between the coordinate system of the robot and the coordinate system of the work object. For example, it is necessary to associate the coordinate system of a tool at the tip of a robot with the coordinate system of a workpiece carried by a conveyor.

When setting such a coordinate system correspondence, the arm of the robot holds one of the object such as a mark imaged by the visual sensor and the visual sensor, and the other is supported by a predetermined support part. Then, the tip of the arm moves to various positions based on the coordinate system setting program. Further, based on the coordinate system setting program, a visual sensor images the object at each position, and coordinate systems are associated based on the obtained image data.

This setting is performed on the premise that the positions of the target and visual sensor do not change. However, for example, unintended tension, inertial force, etc. may act on the cable of the visual sensor, and in this case, there is a possibility that the visual sensor may be misaligned during the above settings. Therefore, there is a need for a robot parameter setting device that can ensure that unintended situations do not occur.

A parameter setting device for a robot according to one aspect of the present invention includes a first setting element that is one of an object and a sensor and is attached to an arm of the robot, and a second setting element that is the other of the object and the sensor. element, and a control unit that causes the arm to perform a parameter setting operation for arranging the first setting element at a plurality of positions, and the control unit is configured to perform a first half of the setting operation or a parameter setting operation for arranging the first setting element at a plurality of positions. Before the operation, the control unit causes the sensor to acquire first check data regarding the object with the first setting element placed at the setting check position, and the controller controls the second half of the setting operation or the After the setting operation, the control unit causes the arm to perform an operation of arranging the first setting element at the setting check position, and causes the sensor to acquire second check data regarding the object; Based on the first check data and the second check data, it is determined whether the position of the first setting element or the second setting element has changed.

1 is a schematic perspective view of a robot parameter setting device according to a first embodiment and a robot system in which the setting device is used; FIG. FIG. 1 is a schematic side view of a robot system according to a first embodiment. FIG. 2 is a block diagram of a control device of the robot parameter setting device according to the first embodiment. FIG. 2 is a block diagram of an image processing device of the robot parameter setting device according to the first embodiment. 3 is a flowchart of an example of processing performed by the control unit of the robot parameter setting device according to the first embodiment. 3 is a flowchart of an example of processing performed by the control unit of the robot parameter setting device according to the first embodiment. 3 is a display example of the display device of the robot parameter setting device according to the first embodiment. FIG. 2 is a schematic perspective view of a robot parameter setting device according to a second embodiment and a robot system in which the setting device is used. 12 is a flowchart of an example of processing performed by the control unit of the robot parameter setting device according to the second embodiment. 12 is a flowchart of an example of processing performed by the control unit of the robot parameter setting device according to the second embodiment.

In a first embodiment, a robot parameter setting device will be described with reference to the drawings. As shown in FIG. 1, the setting device includes, for example, a control device 20 for a robot 10, a visual sensor (sensor) 50, and an image processing device 40 connected to the control device 20. The control device 20 may take on the functions of the image processing device 40, and in this case, the image processing device 40 can be omitted. In addition, another computer may be responsible for part of the processing described below. In this case, the setting device includes the other computer.

Although the robot 10 is not limited to a specific type, the robot 10 of the first embodiment is an articulated robot with six axes. The robot 10 may be a horizontal articulated robot, a multi-link robot, or the like. The arm 10a includes a plurality of servo motors 11 that respectively drive a plurality of movable parts 12 (see FIGS. 1 and 3). Each servo motor 11 has an operating position detecting device 11a for detecting its operating position, and the operating position detecting device 11a is an encoder, for example. The control device 20 receives the detection value of the operating position detection device 11a.

As shown in FIG. 2, for example, a tool 30 is attached to the tip of an arm 10a, and the arm 10a is part of a robot system that performs work on a workpiece W on a transfer device 2. In the example of FIG. 2, a camera 3 separate from the visual sensor 50 is provided on the upstream side of the transport device 2 in order to confirm the position and posture of the work object W. Further, a motor (drive device) 2 a that drives the conveyance device 2 is provided with an encoder (operating position detection device) 2 b that detects the amount of conveyance of the conveyance device 2 . Further, using the position of the work object W detected based on the output of the camera 3 and the conveyance amount of the transport device 2, the control device 20 causes the tip of the arm 10a to follow the work object W during work.

The above operations are known operations such as taking out the work object W, processing the work object W, and attaching parts to the work object W. The processing for the work object W is known processing such as machining, painting, and cleaning. The transport device 2 may be any device that can move the work object W, such as a conveyor, an automatic guided vehicle (AGV), or a car under manufacture. In the case of a car being manufactured, the chassis, tires, motor, etc. function as a transport device 2, and a work object W such as a body on the chassis is transported.

In one example, the tool 30 is a hand, and the tool 30 is equipped with a servo motor 31 that drives a claw (FIG. 3). The servo motor 31 has an operating position detection device for detecting its operating position, and the operating position detection device is an encoder, for example. The detection value of the operating position detection device is transmitted to the control device 20. As each

servo motor

11, 31, various servo motors such as a rotary motor, a linear motor, etc. can be used.

In one example, the visual sensor 50 is supported on the top surface of the transport device 2. In the first embodiment, the visual sensor 50 is supported by a predetermined support part 70 (FIG. 1), such as a plate placed on the top surface of the transport device 2. The visual sensor 50 is, for example, a camera such as a two-dimensional camera. Other types of sensors capable of acquiring imaging data or detection data of the object 60 can also be used as the visual sensor 50.

As shown in FIG. 3, the control device 20 includes a processor 21 having one or more processor elements such as a CPU or a microcomputer, and a display device 22. The control device 20 has a storage unit 23 including nonvolatile storage, ROM, RAM, and the like. The control device 20 includes a servo controller 24 corresponding to the servo motor 11 of the robot 10 and a servo controller 25 corresponding to the servo motor 31 of the tool 30. The control device 20 also includes an input section 26 connected to the control device 20 by wire or wirelessly. In one example, the input unit 26 is an input device such as an operation panel that the user can carry. In other examples, input unit 26 is a tablet computer. In the case of a tablet computer, the input is performed using a touch screen function. The operating panel or tablet computer may also have a display device 22 .

The storage unit 23 stores a system program 23a, and the system program 23a is responsible for the basic functions of the control device 20. Furthermore, the storage unit 23 stores an operation program 23b. The storage unit 23 also stores a parameter setting program 23c and a setting check program 23d. The control device 20 controls the arm 10a to perform a predetermined work on the work object W based on the operation program 23b.

As shown in FIG. 4, the image processing device 40 includes a processor 41 having one or more processor elements such as a CPU, a microcomputer, and an image processing processor. The image processing device 40 is connected to the control device 20 and the visual sensor 50, and includes an input section 42 and a storage section 43 having nonvolatile storage, ROM, RAM, etc. A known image processing program 43a is stored in the storage unit 43.

The image processing device 40 performs known image processing on the image data obtained by the visual sensor 50 based on the image processing program 43a. For example, the image processing device 40 performs known image processing such as binarization processing, blob analysis processing, and edge detection processing on the image data of the target 60. The image processing device 40 may obtain position detection data such as the feature position and center of gravity position of the object 60. It is also possible for the image processing device 40 to obtain posture detection data of the object 60. The image processing device 40 sequentially transmits image data, position detection data, posture detection data, etc. that have been subjected to image processing to the control device 20.

The control device 20 may be responsible for some or all of the functions of the image processing device 40, or the image processing device 40 may be responsible for some or all of the functions of the control device 20. Further, another computer may perform part or all of the functions of the image processing device 40 and the control device 20. In the following description, the image processing device 40, the control device 20, and other computers are referred to as a control section, and the following computer processing is performed by one or more processors of the control section. The one or more processors are processor 21, processor 41, etc.

The control unit performs the following processing for parameter setting based on the parameter setting program 23c and the setting check program 23d. An example of parameter setting will be described with reference to flowcharts in FIGS. 5 and 6.
Here, as shown in FIG. 1, the reference coordinate system 101 of the arm 10a of the robot 10 is set in advance, for example, based on the base 13 that supports the arm 10a. Further, the control unit can calculate the position and orientation of the tip end portion of the arm 10a such as the flange 10b in the tip coordinate system 102 based on the detection result of the operating position detection device 11a.

In the first embodiment, an object (first setting element) 60 such as a calibration jig is attached to the tip of the arm 10a for setting the parameters. In one example, an object 60 is held by tool 30, as shown in FIG. The object 60 may be attached to the wrist flange 10b by a magnet such as an electromagnet, or by attachment means such as a bolt. In the first embodiment, the center position of the mark 61 of the target 60 is arranged at a position corresponding to the tool center point (TCP) of the tool 30.

Furthermore, in the first embodiment, the visual sensor (second setting element) 50 is supported by the support section 70 for the parameter setting. The support section 70 may be the upper surface of the transport device 2, or may be a support device such as a tripod. For example, the position and orientation of the visual sensor 50 on the support portion 70 correspond to the work reference coordinate system for the work object W. The work reference coordinate system corresponds to the position and orientation of the work object W, the position and orientation of the mounting part of the work object W, and the like. In the first embodiment, the work reference coordinate system and the sensor coordinate system 103 of the visual sensor 50 match. This allows the arm 10a to accurately work on the work object W by setting parameters to be described later. In the first embodiment, the optical axis of the visual sensor 50 corresponds to one axis such as the Z axis of the sensor coordinate system 103 and extends vertically upward, but the optical axis of the visual sensor 50 is directed in another direction. It's okay.

The target 60 in the first embodiment has a mark 61, and the control unit recognizes the size, shape, arrangement of each element, etc. of the mark 61 in advance. Thereby, the control unit can calculate the position and orientation of the mark 61 and the object 60 with respect to the visual sensor 50 based on the image data of the mark 61. For example, the center position of the mark 61 is calculated as the position of the mark 61, and the orientation of the mark 61 is calculated based on the relative positions of three or more feature shapes or feature points in the mark 61. The mark 61 may be a dot pattern, a single or multiple three-dimensional shapes, or the like. When the object 60 is a work object W, a single or plural characteristic shapes of the work object W function as the mark 61. The target 60 may be provided with a thin tip, and this tip may be used instead of the mark 61.

First, upon receiving an input to start parameter setting (step S1-1), the control section performs the following processing based on the setting check program 23d. In one example, the start input is based on a user input to input portion 26 .
Here, the user moves the tip of the arm 10a so that the object 60 is within the field of view of the visual sensor 50. At this time, a parameter setting screen 23g shown in FIG. 7 is displayed on the display device 22. Preferably, the control unit displays on the display device 22 a preparation image or text 23h that prompts the distal end of the arm 10a to be placed at the setting check position (step S1-2). The control unit may display on the display device 22 a preparation image or text 23h that prompts the user to place the target 60 at the setting check position.

The term setting check position means the position and attitude of the tip of the arm 10a, and the setting check position is the position and attitude of the tip where the object 60 is placed within the field of view of the visual sensor 50. The preparation image or text 23h in step S1-2 may be a screen that informs the user that the setting check position will be used for determination in step S1-17, which will be described later. In this case, the user can appropriately set the position and orientation of the tip in step S1-1 while considering various conditions. The various conditions include the configuration including the wiring of the robot 10, the configuration including the wiring of the visual sensor 50, the size of the robot 10, the type of the tool 30, the size of the tool 30, and the like. Note that if the content regarding step S1-2 is described in an instruction manual or the like, the control unit may be configured not to perform step S1-2.

When the control unit receives the parameter setting process start input (step S1-3), it causes the visual sensor 50 to acquire the first check data 23e (FIG. 3) at the setting check position (step S1-4). Further, the control unit stores the first check data 23e, which is the imaging data or detection data obtained by the visual sensor 50, in the storage unit 23 or the like (step S1-5). Before step S1-4, the control unit may cause the arm 10a to perform an operation to eliminate the influence of backlash on the arm 10a. In one example, for this operation, the controller rotates each servo motor 11 slightly and then returns it to its original position.

Next, the control unit performs the following processing based on the parameter setting program 23c. The control unit controls the arm 10a to place the object 60 at a plurality of positions, for example, three or more calibration positions, and causes the visual sensor 50 to take an image at each calibration position. The postures of the target 60 at each calibration position may be different from each other.

For example, the control unit places the object 60 at the first calibration position (step S1-6) and causes the visual sensor 50 to acquire data at the first calibration position (step S1-7). Further, the control unit places the object 60 at the second calibration position (step S1-8) and causes the visual sensor 50 to acquire data at the second calibration position (step S1-9). Further, the control unit places the object 60 at the third calibration position (step S1-10) and causes the visual sensor 50 to acquire data at the third calibration position (step S1-11).

The control unit calculates the position and orientation of the object 60 with respect to the visual sensor 50 at each calibration position from the imaging data of steps S1-7, S1-9, and S1-11 (step S1-12). These positions and orientations are the positions and orientations of the visual sensor 50 on the sensor coordinate system 103. Further, the control unit recognizes the position and orientation of at least one of the tip of the arm 10a, the tool 30, and the tip coordinate system 102 at each calibration position. The control unit sets parameters using the position and orientation on the sensor coordinate system 103 and the position and orientation of each calibration position, for example, on the tip coordinate system 102 (step S1-13).

The parameter is, for example, one that associates the sensor coordinate system 103 with the tip coordinate system 102 and the reference coordinate system 101. The parameters are, for example, those that associate the work reference coordinate system with the positions and postures of the tip of the arm 10a, the tool 30, and the tip coordinate system 102. If the sensor coordinate system 103 corresponds to the coordinate system of the transport device 2, the work by the arm 10a can be performed accurately. Alternatively, the parameter associates the tip coordinate system 102 with the tip (TCP) of the tool 30.
The parameters may have other uses, and other calculations may be employed to set the parameters. Furthermore, in the first embodiment, the position and orientation of the visual sensor 50 correspond to the work reference coordinate system for the work object W. Alternatively, the control device 20 may recognize the position and direction of the TCP without any corresponding response.

Subsequently, the control unit performs the following processing based on the setting check program 23d. The control unit controls the arm 10a so that the distal end of the arm 10a is placed at the setting check position (step S1-14). Further, the control unit causes the visual sensor 50 to acquire the second check data 23f (FIG. 3) at the setting check position (step S1-15). Then, the control unit stores the second check data 23f, which is the imaging data or detection data obtained by the visual sensor 50, in the storage unit 23 or the like (step S1-16).

Next, the control unit determines whether there is a change in the position of the visual sensor 50 or the object 60 by comparing both

check data

23e and 23f (step S1-17). For example, when the amount of change in the position of the object 60 in the second check data 23f with respect to the first check data 23e is less than a threshold value, it is determined that there is no change in position. At this time, the control section displays a message indicating that parameter setting has been completed on the display device 22 (step S1-21), and normally ends the parameter setting process. Furthermore, it is determined that there is a position change when the amount of position change is greater than or equal to a threshold value. The threshold value is, for example, 3 pixels of the imaging data of the visual sensor 50, but if it is determined that there is a positional change when the threshold value is 2 pixels or more, the parameter setting becomes more accurate.

It is also possible to set 0.5 mm as the threshold value to determine the presence or absence of a positional change. For example, the amount of positional change is the amount of positional change of a portion of the mark 61 on the object 60 where the largest positional shift has occurred. If it is determined that there is a positional change when the amount of positional change is 0.3mm or 0.2mm or more instead of 0.5mm or more, the parameter setting becomes more accurate. For example, the position of the visual sensor 50 may shift slightly during parameter setting due to tension on the cable of the visual sensor 50. Since the event occurs during a relatively short parameter setting, a slight change in the position of the visual sensor 50 or the object 60 can be accurately determined. Note that it is also possible to use a threshold value greater than the above value depending on the situation or conditions.

Subsequently, when it is determined in step S1-17 that there is a change in position, the control section displays the amount of change in position on the display device 22 (step S1-18). The number of pixels, a numerical value in millimeters, etc. are used as the amount of positional change. In step S1-18, it is also possible for the control unit to display on the display device 22 a determination that there is a change in position. As a display of the judgment, an error display, a display indicating that the parameter cannot be set, etc. are also possible. This allows the user to know the position change in a timely manner.

Note that when it is determined in step S1-17 that there is no position change, the control unit may display on the display device 22 a display indicating that there is no position change. The display allows the user to know in a timely manner that the set parameters are accurate. The amount of positional change may be displayed on the display device 22 as an indication that there is no positional change. Note that by making the characters and screen color different from those in step S1-18 when displaying the amount of positional change in this way, the user can easily recognize that there has been no positional change.

Furthermore, by displaying the amount of positional change, it becomes possible for the user to estimate the accuracy of parameter setting. For example, the tool 30 may be a long and thin welding gun, a hand with long claws, etc., and the object 60 may be attached to the tip thereof. For example, the work performed by the tool 30 may not require much positional accuracy. There are also various conditions mentioned above. When these conditions exist, the user can judge the suitability of 4 pixels based on the conditions, experience, etc. The user may be able to estimate the accuracy of the parameter settings based on the appropriateness.

The control unit may display the direction of the position change on the display device 22. In this case, the direction of change in the position of the visual sensor 50, the direction of change in the position of the object 60, etc. are displayed on the display device 22. The direction may be an approximate direction. This display makes it easier for the user to estimate the cause of the position change, which leads to improved efficiency in setting work.

Assuming such a case, when it is determined in step S1-17 that the position has changed, the control unit displays a selection screen on the display device 22 that allows the user to select whether or not to use the parameter. (Step S1-19). Thereby, the user can decide whether to use or not use the parameter based on the conditions, experience, etc. Note that the control unit is configured not to perform step S1-19 when there is no need for the selection.

Note that when the user makes a selection to use the control unit in step S1-19, the control unit stores data linking the content of the selection, the amount of position change, and the parameter in the storage unit 23. You may save it.
Alternatively, when it is determined in step S1-17 that there is a position change, the control unit may store data in which the position change amount and the parameter are linked in the storage unit 23.
Further, the control unit may transmit the data to an external computer. The external computer is a server for production control, quality control, etc. The data can be used for later quality control operations, the design and improvement of the robot system, the design and improvement of the work object W, and the like.

Then, when the control unit receives an input to use the parameter through the input unit 26 or the like (step S1-20), the parameter is set and a display indicating that the parameter setting is completed is displayed (step S1-21). If the control unit does not accept the input to use the parameter (step S1-20), the process ends without setting the parameter (step S1-22).

Note that instead of step S1-2, the control unit may automatically place the tip of the arm 10a at the setting check position. At this time, the control unit may display a plurality of setting check positions as options on the display device 22 by illustration or the like. In this case, the control unit displays a screen on the display device 22 that allows the user to select one of the plurality of setting check positions. The control unit receives a user's selection input via the input unit 26, and automatically places the tip of the arm 10a at a setting check position corresponding to the selection input.

Additionally, the control unit may display a screen on the display device 22 for setting the setting check position. For example, a screen is displayed that shows at least the position of the visual sensor 50. On this screen, at least the position of the tip of the arm 10a, the tool 30, or the object 60 can be specified. The control unit receives a user's setting input via the input unit 26, and automatically places the tip of the arm 10a at a setting check position corresponding to the setting input.

A second embodiment of a robot parameter setting device will be described with reference to the drawings. In the first embodiment, the object (first setting element) 60 is attached to the tip of the arm 10a, and the visual sensor (second setting element) 50 is supported by the support section 70. In the second embodiment, a visual sensor (first setting element) 50 is attached to the tip of the arm 10a, and a target (second setting element) 60 is supported by a support section 70 (FIG. 8). In the second embodiment, the same components as those in the first embodiment are denoted by the same reference numerals, and descriptions of the configurations and similar effects obtained by the configurations are omitted. Note that the modifications described in the first embodiment can also be applied to the second embodiment as appropriate.

In the second embodiment, the visual sensor 50 is removably attached to the tip of the arm 10a. In one example, visual sensor 50 is attached to wrist flange 10b of arm 10a, similar to tool 30. In one example, the object 60 is supported on the top surface of the transport device 2 . In the second embodiment, the object 60 is supported by a support section 70 placed on the top surface of the transport device 2 . The object 60 may be the work object W, or may be an article other than the work object W, a part of a structure, or the like. A part of a conveyance device or the like can be used as the structure part.

In the second embodiment as well, the following processing for parameter setting is performed based on the parameter setting program 23c and the setting check program 23d. An example of parameter setting will be described with reference to flowcharts in FIGS. 9 and 10.

In the second embodiment, a visual sensor 50 is attached to the tip of the arm 10a for setting the parameters. In one example, the visual sensor 50 is attached to the wrist flange 10b using a magnet such as an electromagnet, a bolt, or other attachment means. The visual sensor 50 may be attached to the tip of the arm 10a by holding the visual sensor 50 with the tool 30.

Furthermore, in the second embodiment, the object 60 is supported by the support section 70 for the parameter setting. The support section 70 may be the upper surface of the transport device 2, or may be a support device such as a tripod. For example, the position and orientation of the object 60 on the support part 70 correspond to the work reference coordinate system for the work object W. In this sense, if a plurality of work objects W or a single work object W is used as the object 60, the parameter settings can be made suitable for the work. For example, the camera coordinate system 103, the reference coordinate system 101, and the tip coordinate system 102 are associated with each other by setting parameters to be described later. Further, by setting parameters to be described later, it becomes possible for the arm 10a to accurately perform work on the work target W, for example.

First, the control unit performs the following processing based on the setting check program 23d.
In the second embodiment, the user moves the tip of the arm 10a so that the object 60 is within the field of view of the visual sensor 50 according to the instructions in the instruction manual. In the second embodiment, the control unit does not display on the display device 22 the preparation image or text 23h that prompts the distal end of the arm 10a to be placed in the setting check position. It is also possible to configure the first embodiment in this way.

Upon receiving an input to start the parameter setting process (step S2-1), the control unit causes the visual sensor 50 to acquire the first check data 23e at the setting check position (step S2-2). Further, the control unit stores the first check data 23e, which is the imaging data or detection data obtained by the visual sensor 50, in the storage unit 23 or the like (step S2-3). Before step S2-2, the control unit may cause the arm 10a to perform an operation to eliminate the influence of backlash on the arm 10a.

Next, the control unit performs the following processing based on the parameter setting program 23c, similar to the first embodiment.
For example, the control unit places the visual sensor 50 at the first calibration position (step S2-4), and causes the visual sensor 50 to acquire data at the first calibration position (step S2-5). Further, the control unit places the visual sensor 50 at the second calibration position (step S2-6), and causes the visual sensor 50 to acquire data at the second calibration position (step S2-7). Further, the control unit places the visual sensor 50 at the third calibration position (step S2-8), and causes the visual sensor 50 to acquire data at the third calibration position (step S2-9).

The control unit calculates the position and orientation of the object 60 with respect to the visual sensor 50 at each calibration position from the imaging data of steps S2-5, S2-7, and S2-9 (step S2-10). These positions and orientations are the positions and orientations of the visual sensor 50 on the sensor coordinate system 103. Further, the control unit recognizes the position and orientation of at least one of the tip of the arm 10a, the tool 30, and the tip coordinate system 102 at each calibration position. The control unit sets parameters using the position and orientation on the sensor coordinate system 103 and the position and orientation of each calibration position, for example, on the tip coordinate system 102 (step S2-11).

The parameters are, for example, those that associate the sensor coordinate system 103 with the tip coordinate system 102 and the reference coordinate system 101.
The parameters may be for other purposes, and other calculations may be employed to set the parameters.

Subsequently, the control unit performs the following processing based on the setting check program 23d. The control unit controls the arm 10a so that the distal end of the arm 10a is placed at the setting check position (step S2-12). Further, the control unit causes the visual sensor 50 to acquire the second check data 23f at the setting check position (step S2-13). Then, the control unit stores the second check data 23f, which is the imaging data or detection data obtained by the visual sensor 50, in the storage unit 23 or the like (step S2-14).

Subsequently, the control unit determines whether there is a change in the position of the visual sensor 50 or the object 60, as in step S1-17 of the first embodiment (step S2-15). If there is no positional change, the control section displays a message indicating that the parameter setting has been completed on the display device 22 (step S2-19), and normally ends the parameter setting process.
Further, the control unit displays the amount of position change on the display device 22 (step S2-16), similarly to step S1-18 of the first embodiment. The display of the amount of change in position allows the user to estimate the accuracy of parameter setting, as in the first embodiment.

Further, the control unit may display a selection screen on the display device 22 in the same manner as step S1-19 of the first embodiment (step S2-17). Thereby, the user can decide whether to use or not use the parameter based on the conditions, experience, etc., as in the first embodiment.
Further, when the control unit receives an input to use the parameter through the input unit 26 or the like (step S2-18), the control unit sets the parameter and displays the completion of parameter setting (step S2-19). . If the control unit does not accept the input to use the parameter (step S2-18), the process ends without setting the parameter (step S2-20).

Here, in the parameter setting process, the tip of the robot 10 sequentially moves to a plurality of positions and postures, for example, as in steps S1-6 to S1-11 of the first embodiment. Furthermore, various objects such as other devices and work objects W exist around the robot. Further, a cable for the robot 10 exists around the robot 10, and the cable also moves according to the movement of the robot. Therefore, during the parameter setting process, the user needs to be careful to avoid interference between the robot 10 and the cables and surrounding objects. Therefore, the user often does not notice the state of the visual sensor 50 or its cable.

Further, the visual sensor 50 is attached to the robot 10 or the support part by a user or the like for parameter setting, and its cable is also temporarily placed by the user. Therefore, depending on the temporary position of the cable, the visual sensor 50 may apply a slight tension to the cable during the parameter setting operation of the robot 10. The visual sensor 50 may or may not move due to the slight tension. Further, even if the visual sensor 50 is slightly displaced due to the slight tension, the user often does not notice the displacement. The position of the object 60 may also shift slightly due to vibrations, etc., but similarly, in many cases, the user does not notice this shift.

In one example, even if there is a slight deviation, the parameter setting calculation itself is performed, so conventionally, the parameter processing ends normally and the user does not notice the deviation. Although it depends on the accuracy required for the robot 10 to perform the work on the work object W, there may be some work in which the user does not notice the slight deviation at all. However, even in such work, if any error occurs, the cause may be related to the slight deviation.

In the first and second embodiments, the first and

second check data

23e and 23f are measured and position changes are determined during a series of controls for setting parameters of the robot 10. This configuration measures the first and

second check data

23e and 23f during parameter setting for a relatively short period of time, so it is possible to accurately determine a slight positional deviation of the visual sensor 50 or object 60 that occurs during parameter setting. can.

For example, in step S1-17, if the positions of the first check data 23e and the second check data 23f differ by 3 pixels or more, it is determined that there is a position change. In one example, the visual sensor 50 has several million pixels, and one side of the angle of view of the visual sensor 50 at the position of the object 60 is about 10 cm to 20 cm. In this case, a position change of 3 pixels may correspond to a position change of 0.2 mm, 0.3 mm, etc. Therefore, the above configuration can accurately determine a slight positional shift of the visual sensor 50 or the object 60.

If the visual sensor 50 is slightly deviated in the optical axis direction during image capture at the second setting check position, the deviation will almost never occur only in the optical axis direction of the visual sensor 50. In other words, when the visual sensor 50 is displaced in the optical axis direction due to some unintended cause, a situation in which the visual sensor 50 is not displaced in the direction intersecting the optical axis is unlikely to occur. The same applies to the target 60. Therefore, the above configuration can accurately determine a slight positional shift of the visual sensor 50 or the object 60.

Furthermore, in the first and second embodiments, the user moves the tip of the arm 10a before steps S1-4 and S2-2, and this position is used as the setting check position. Therefore, the user can easily and reliably determine the setting check position, and there is no need to separately set the setting check position. This contributes to improving user convenience. Further, the user can reliably place the visual sensor 50 in a focused position as the setting check position. This configuration is useful in view of the fact that many visual sensors 50 for robots do not have an autofocus function, and the in-focus range is known from the instruction manual or the like.

Furthermore, in the first and second embodiments, a screen for selecting a setting check position is displayed. Therefore, the user can easily use a setting check position suitable for conditions such as cable wiring and position of the visual sensor 50.

Furthermore, in the first and second embodiments, a screen for setting a setting check position is displayed. This is useful for the user to arbitrarily set the setting check position without much effort.

Note that in the first and second embodiments, it is also possible to use at least one of the calibration positions as the setting check position. For example, when the first calibration position is used as the setting check position, the tip of the arm 10a is placed at the first calibration position in steps S1-14 and S2-12. Even in this case, the same effects as described above can be achieved. Note that the setting check position is preferably the first half of the setting operation in steps S1-6 to S1-11 of the first embodiment, for example. In other words, it is preferable to use the first calibration position or the second calibration position. Preferably, for example, in the first embodiment, steps S1-12 and S1-13 are performed in the latter half of the setting operation of steps S1-6 to S1-11 or after the setting operation.

In addition, in the first and second embodiments, other setting check positions may be further set. Other setting check positions may be set, for example, at positions where tension is likely to be applied to the cable of the visual sensor 50. The other setting check positions may be any of the calibration positions. There may be cases where the setting check position is automatically set by the control unit, or there may be cases where the setting check position is set in advance in the control unit. In these cases, the control unit may be configured to display the setting check position on the display device 22. For example, the control unit displays that the setting check position is a position where the arm 10a stops before the first calibration position, a position between the first calibration position and the second configuration position, or the like. In this case, the user can understand where the setting check position is, which contributes to facilitating identification of the cause of an error during setting work.

Note that in the first and second embodiments, the visual sensor 50 is a three-dimensional camera, a three-dimensional distance sensor, LiDAR (Light Detection and Ranging), PSD (Position
Sensing Detector) etc. may also be used. In these cases, the configuration of the image processing device 40 is changed as appropriate. Further, as the visual sensor 50, a visual sensor that is attached to the tip of the arm 10a while performing the work on the work object W may be used.

Although the embodiments of the present disclosure have been described in detail, the present disclosure is not limited to the individual embodiments described above. These embodiments may include various additions and substitutions without departing from the gist of the invention or the spirit and spirit of the present invention derived from the content described in the claims and equivalents thereof. , change, partial deletion, etc. are possible. For example, in the embodiments described above, changing the order of each operation, changing the order of each process, omitting or adding some operations depending on conditions, omitting or adding some processes depending on conditions, etc. It is possible without being restricted to the example. Further, the same applies when numerical values or formulas are used in the description of the above embodiments.

2 Transfer device 10 Robot 10a Arm 11 Servo motor 20 Control device 21 Processor 22 Display device 23 Storage section

23a System program

23b Operation program 23c Parameter setting program 23d Setting check program 23e First check data 23f Second check data 26 Input section 30 Tool 31 Servo motor 40 Image processing device 41 Processor 43 Storage unit 43a Image processing program 50 Visual sensor (sensor)
60 Target 61 Mark 70 Support part 101 Reference coordinate system 102 Tip coordinate system 103 Sensor coordinate system W Work target

Claims

a first configuration element, which is one of an object and a sensor and is attached to the arm of the robot;
a second setting element that is the other of the target and the sensor;
a control unit that causes the arm to perform a parameter setting operation for arranging the first setting element at a plurality of positions;
The control unit acquires first check data regarding the object to the sensor in a state where the first setting element is placed at a setting check position during the first half of the setting operation or before the setting operation. let me,
The control unit causes the arm to perform an operation of arranging the first setting element at the setting check position in the latter half of the setting operation or after the setting operation, and also causes the arm to perform an operation of arranging the first setting element at the setting check position, and also controls second check data regarding the object. to be acquired by the sensor,
The control unit determines whether or not there is a change in the position of the first setting element or the second setting element based on the first check data and the second check data, and the control unit sets parameters of the robot. Device.
Before arranging the first setting element at a plurality of positions for setting the parameters, the control unit performs the setting check on the position where the first setting element is placed by moving the arm by the user. The robot parameter setting device according to claim 1, which is used as a position.
The robot parameter setting device according to claim 1 or 2, further comprising a display device that displays a determination that there is a position change.
The robot parameter setting device according to claim 1 or 2, further comprising a display device that displays the amount of the position change when there is a position change.
The robot parameter setting device according to claim 1 or 2, further comprising a display device that displays the direction of the position change when the position change occurs.
3. The robot parameter setting device according to claim 1, further comprising a display device that displays a screen for allowing the user to set or select the setting check position.
3. The robot parameter setting method according to claim 1, wherein after the controller determines that there is a change in the position, a screen is displayed on the display device that allows the user to select whether or not to use the set parameters. Setting device.
The robot parameter setting device according to claim 1 or 2, wherein the second setting element is supported by a predetermined support part.
A robot comprising the robot parameter setting device according to any one of claims 1 to 8.