Offline direct teaching device

Abstract

To provide an offline direct teaching device which allows a user to grasp not only the posture of an actual multi-joint robot during movement but also the reached position when performing teaching by moving a model of a multi-joint robot displayed on a screen by a pointing device.SOLUTION: An offline direct teaching device 100 according to the present invention is the offline direct teaching device which performs teaching of a multi-joint robot while moving an actual multi-joint robot 110 by moving a model 112 of the multi-joint robot displayed on a screen by a pointing device 104, moves the model in response to the operation of the pointing device, displays paths 138a, 138b, 138c of the model semi-transparently in response to the movement of the model, and erases the semi-transparently displayed paths of the model at the operation speed of the actual multi-joint robot in response to the operation of the actual multi-joint robot in the semi-transparently displayed order.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to an offline direct teaching device that teaches an actual articulated robot by moving a model of the articulated robot displayed on a screen with a pointing device. [Background technology]

[0002] When teaching an articulated robot how to move, the mainstream method is to use a teaching pendant to perform the teaching work. Other known methods include direct teaching, where the operator directly moves the robot by hand, and offline teaching, where a motion program is created using computer software.

[0003] Patent Document 1 describes a robot control device (teaching pendant). This robot control device moves a pointing position on the screen that corresponds to the tip of the wrist of the robot by dragging a pointing device on a plane consisting of two axes of an arbitrary motion coordinate system displayed on the screen of a human interface. Then, it translates or rotates a control point that corresponds to the tip of the wrist of the actual robot by an amount proportional to the change in the pointing position on the screen per unit time.

[0004] In this way, the robot control device moves the robot by dragging the pointing position. For this reason, the robot control device in Patent Document 1 is said to provide a more intuitive feeling of manual operation compared to button operations on a teaching pendant.

[0005] Patent Document 2 describes a robot operation device (teaching pendant). The robot operation device includes an input operation unit that receives input operations from a user, and a motion command generation unit. The motion command generation unit generates motion commands for operating a multi-joint robot having multiple drive shafts based on the input operations input to the input operation unit. Furthermore, the motion command generation unit can perform an operation amount determination process that determines the amount of input operation input to the input operation unit, and a movement amount calculation process that calculates the movement amount of the robot based on the operation amount of the input operation.

[0006] For this reason, in a robot operation device, there is a correlation between the amount of input operation performed by the user on the input operation unit and the amount of movement of the robot. As a result, in the robot operation device of Patent Document 2, the user can adjust the amount of movement of the robot by adjusting the amount of input operation, enabling intuitive operation and improving operability, which results in improved safety.

[0007] Patent Document 3 describes an information processing device (HMD: Head Mounted Display) equipped with a processor and a display device (offline teaching). The processor includes an environment model storage unit, a robot model storage unit, a simulation unit, and an MR image generation unit. The environment model storage unit stores an environment model that models the actual environment in which the robot is installed. The robot model storage unit stores a robot model that models the robot.

[0008] When a robot movement trajectory display mode that displays the movement trajectory of the robot is selected, the simulation unit obtains an environmental model from the environmental model storage unit, obtains a robot model from the robot model storage unit, operates the robot model based on the movement sequence, and stores the movement trajectory of the robot in memory.

[0009] The MR image generator also superimposes a robot model image at the installation position of the robot in the real environment, generates an MR image so that the robot motion trajectory image is superimposed, and displays it on the display device. Furthermore, the MR image generator displays only the outline of the robot motion trajectory image at each timing, or displays it partially or entirely semi-transparently. As a result, the HMD of Patent Document 3 is said to be able to more reliably check whether the robot will interfere with surrounding objects before installing the robot. [Prior art documents] [Patent documents]

[0010] [Patent Document 1] Japanese Patent Application Publication No. 09-103978 [Patent Document 2] JP 2016-068237 A [Patent Document 3] JP 2022-186476 A Summary of the Invention [Problem to be solved by the invention]

[0011] The technologies in Patent Documents 1 and 2 involve the development of teaching pendants, with Patent Document 1 enabling pen input and Patent Document 2 being equipped with a lever (joystick) that allows intuitive robot operation. Furthermore, since offline teaching does not always involve moving the actual device during operation, when teaching by moving the robot model with a pointing device, the robot model on the screen can move at high speed by following the movement of the cursor on the pointing device.

[0012] However, due to mechanical and safety limitations, an actual robot cannot move as fast as it can on a screen. Also, teaching on a computer is limited to identifying the start and end points of each movement, and it is not possible to grasp the movement of the robot during its movement (the robot's posture).

[0013] For this reason, even if the robot may move in an unintended posture, the posture of the robot cannot be grasped without actually moving the robot. Depending on the calculation of the inverse motion, a large change in the axis value may suddenly occur, such as the robot's wrist rotating.

[0014] The technology of Patent Document 3 generates MR images on which the robot motion trajectory image is superimposed, making it possible to grasp the motion trajectory of the robot. However, although the technology of Patent Document 3 uses MR images to check for the risk of interference, the teaching itself is already completed, and the image is not displayed during teaching.

[0015] Therefore, it is not possible to grasp the posture of the robot during movement during teaching, and in particular, it is not possible to grasp the position the robot has reached (or how late it will follow the movement of the mouse cursor), as it moves with a lag behind the movement of the mouse cursor.

[0016] In view of these problems, the present invention aims to provide an offline direct teaching device that can grasp not only the posture of an actual articulated robot during movement but also the position it reaches when teaching is performed by moving a model of the articulated robot displayed on a screen with a pointing device. [Means for solving the problem]

[0017] In order to solve the above problems, a representative configuration of an offline direct teaching device according to the present invention is an offline direct teaching device that teaches a multi-joint robot by moving a model of the multi-joint robot displayed on a screen with a pointing device while also moving the actual multi-joint robot, the model is moved in accordance with the operation of the pointing device, the path of the model is displayed semi-transparently in accordance with the movement of the model, and the semi-transparently displayed path of the model is erased in the order in which it is displayed semi-transparently, at the movement speed of the actual multi-joint robot, in conjunction with the movement of the actual multi-joint robot.

[0018] It is preferable that the above model path is drawn by displaying the model for each unit time semi-transparently. Effect of the Invention

[0019] According to the present invention, it is possible to provide an offline direct teaching device that can grasp not only the posture of the actual articulated robot during movement but also the position it reaches when teaching is performed by moving a model of the articulated robot displayed on a screen with a pointing device. [Brief description of the drawings]

[0020] [Figure 1] 1 is a diagram illustrating an overview of an offline direct teaching device according to an embodiment of the present invention. FIG. [Diagram 2] 2 is a block diagram showing the functions of the offline direct teaching device of FIG. 1. [Diagram 3] 4 is a flowchart showing the operation of the offline direct teaching device of FIG. 1. [Figure 4] 2 is a diagram showing how teaching is performed by moving a model displayed on a display unit of the offline direct teaching device in FIG. 1 with a pointing device. FIG. [Diagram 5] FIG. 5 is a diagram showing the state of teaching by the offline direct teaching device subsequent to FIG. 4. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0021] A preferred embodiment of the present invention will be described in detail below with reference to the accompanying drawings. The dimensions, materials, and other specific values ​​shown in the embodiment are merely examples for facilitating understanding of the invention, and do not limit the present invention unless otherwise specified. In this specification and drawings, elements having substantially the same functions and configurations are given the same reference numerals to avoid repeated explanations, and elements not directly related to the present invention are not shown.

[0022] 1 is a diagram for explaining an overview of an offline direct teaching device in an embodiment of the present invention. The offline direct teaching device (hereinafter, teaching device 100) includes a computer 102 and software executed on the computer 102. The teaching device 100 includes a pointing device 104 such as a mouse, a display unit 106, and a teaching unit 108 shown in FIG.

[0023] The teaching apparatus 100 displays a model 112 of an actual machine, i.e., a robot 110, on a display unit 106 of a computer 102, and further moves the model 112 using a pointer 114 of a pointing device 104, thereby performing teaching while actually moving the actual robot 110.

[0024] The actual robot 110 is, for example, a six-axis articulated robot, and includes a base 116 that is placed on the floor of a factory or the like, a rotating frame 118, a first arm 120, a second arm 122, and an end effector 124. The end effector 124 is attached to a tip 126 of the second arm 122. The speed of the actual robot 110 is limited by these mechanical limitations or safety restrictions.

[0025] On the screen of the display unit 106, the model 112 of the robot 110 can move at high speed by following the movement of the pointer 114. On the other hand, the actual robot 110 is limited in speed as described above, and therefore cannot move as fast as it can on the screen.

[0026] Therefore, teaching on a general computer is limited to identifying the start and end points of each movement, and is not capable of grasping the movement (posture of the robot 110) during the movement of the robot 110. In particular, it is not possible to grasp the position to which the robot 110, which moves with a lag behind the movement of the pointer 114, has reached (how late it follows).

[0027] Therefore, the teaching device 100 employs software that can grasp the posture of the robot 110 during its movement and the position it reaches when teaching is performed by moving a model 112 of the robot 110 displayed on the screen with a pointer 114 of a pointing device 104 and actually moving the robot 110 (see FIG. 2). The teaching device 100 is also connected to the actual robot 110 wirelessly or by wire, and uses software executed on the computer 102 to actually move the robot 110 and perform teaching.

[0028] Fig. 2 is a block diagram showing functions of the teaching device 100 of Fig. 1. The teaching unit 108 of the teaching device 100 has a storage unit 130, an operation detection unit 132, and a display control unit 134. The storage unit 130 stores a model 112 of the robot 110. The operation detection unit 132 detects the position and movement of the pointing device 104. The display control unit 134 controls the display unit 106.

[0029] Fig. 3 is a flow chart showing the operation of the teaching device 100 of Fig. 1. Fig. 4 is a diagram showing how teaching is performed by moving a model 112 displayed on the display unit 106 of the teaching device 100 of Fig. 1 with the pointing device 104. Fig. 5 is a diagram showing the teaching state by the teaching device 100 subsequent to Fig. 4.

[0030] In the teaching device 100, first, the display control unit 134 of the teaching unit 108 reads out the model 112 of the robot 110 from the storage unit 130 and displays the model 112 on the display unit 106 (step S100). In step S100, the model 112 is displayed on the screen together with the working area 136, as shown in FIG. 4(a).

[0031] Next, the operation detection unit 132 detects whether or not the pointing device 104 has been operated by the operator (step S102). If the operation of the pointing device 104 is not detected (No), the operation detection unit 132 repeats the process of step S102.

[0032] In step S102, when operation of the pointing device 104 is detected (Yes), the display control unit 134 moves the model 112 of the robot 110 on the screen following the operation of the pointing device 104, and displays it on the display unit 106 (step S104).

[0033] As an example, in step S104, when the pointing device 104 is operated and the pointer 114 superimposed on the model 112 on the screen shown in FIG. 4(a) moves to the position shown in FIG. 4(b), the display control unit 134 controls the display unit 106 to move the model 112 in FIG. 4(a) to the position in FIG. 4(b) in accordance with the movement of the pointer 114.

[0034] 4(b), the display control unit 134 displays paths 138a, 138b, and 138c of the model 112 semi-transparently, following the movement of the model 112 (step S106). The paths 138a, 138b, and 138c of the model 112 are displayed semi-transparently on the screen in this order, and show the movement (posture) of the robot 110 during its movement. The display control unit 134 also draws the paths 138a, 138b, and 138c of the model 112 by semi-transparently displaying the model 112 for each unit time.

[0035] Therefore, when performing teaching, the operator can grasp the paths 138a, 138b, and 138c of the model 112 of the robot 110 and intuitively grasp the posture of the robot 110 during its movement. In particular, since the paths 138a, 138b, and 138c of the model 112 are displayed semi-transparently for each unit time, the operator can reliably grasp the paths 138a, 138b, and 138c of the model 112.

[0036] Furthermore, by grasping the posture of the robot 110 while it is moving, the worker can set limits on the angular velocity of the joints of the robot 110, thereby preventing the axis values ​​of the robot 110 from unintentionally changing significantly.

[0037] Furthermore, the teaching unit 108 controls the actual robot 110 to operate the robot 110 along the paths 138a, 138b, and 138c of the model 112 in the order that the paths 138a, 138b, and 138c are made semi-transparent.

[0038] Accompanying the movement of the actual robot 110, the display control unit 134 acquires the current posture and position of the actual robot 110 based on position information from, for example, an encoder of the robot 110, which is an articulated robot. Furthermore, using the acquired current posture and position of the robot 110, the display control unit 134 erases the paths 138a, 138b, and 138c displayed semi-transparently of the model 112 in the order in which they were displayed semi-transparently, at the movement speed of the actual robot 110, in association with the movement of the actual robot 110 (step S108).

[0039] In step S108, as shown in Fig. 5(a), of the routes 138a, 138b, and 138c of the model 112, the route 138a (see Fig. 4(b)), which is displayed semi-transparently first, is erased, and only the routes 138b and 138c are displayed together with the model 112. Also, as shown in Fig. 5(b), the route 138b (see Fig. 5(a)), which is displayed semi-transparently next to the route 138a, is erased, and only the route 138c is displayed together with the model 112. Next, as shown in Fig. 5(c), the route 138c is also erased, and only the model 112 is displayed on the screen.

[0040] That is, in step S108, when the robot 110 reaches the positions of the paths 138a, 138b, and 138c displayed semi-transparently on the model 112, the paths 138a, 138b, and 138c are erased in order.

[0041] Then, in step S108, the teaching unit 108 erases all of the paths 138a, 138b, and 138c displayed semi-transparently on the model 112 as shown in FIG. 5(c), and ends the processing when the robot 110 reaches the position indicated by the pointer 114 in FIG. 4(b).

[0042] Therefore, the operator can not only grasp the posture of the robot 110 during its movement based on the paths 138a, 138b, 138c of the model 112 of the robot 110, but also intuitively grasp how far the robot 110 has reached.

[0043] Although the preferred embodiment of the present invention has been described above with reference to the accompanying drawings, it goes without saying that the present invention is not limited to such an example. It is clear that a person skilled in the art can think of various modified or altered examples within the scope of the claims, and it is understood that such examples also naturally belong to the technical scope of the present invention. [Industrial Applicability]

[0044] The present invention can be used as an offline direct teaching device in which teaching is performed by moving a model of an articulated robot displayed on a screen with a pointing device. [Explanation of symbols]

[0045] 100... offline direct teaching device, 102... computer, 104... pointing device, 106... display unit, 108... teaching unit, 110... robot, 112... model, 114... pointer, 116... base, 118... rotating frame, 120... first arm, 122... second arm, 124... end effector, 126... tip of second arm, 130... memory unit, 132... operation detection unit, 134... display control unit, 136... working area, 138a, 138b, 138c... path of model

Claims

1. In an offline direct teaching device, a model of an articulated robot is displayed on a screen, and a teaching operation of the articulated robot is performed while moving the actual articulated robot by using a pointing device. The model is moved in response to the operation of the pointing device; A path of the model is displayed semi-transparently in accordance with the movement of the model; An offline direct teaching device characterized in that the paths of the model displayed semi-transparently are erased in the order in which they are displayed semi-transparently, at the movement speed of the actual articulated robot, in accordance with the movement of the actual articulated robot.

2. 2. The offline direct teaching device according to claim 1, wherein the path of the model is drawn by displaying the model semi-transparently for each unit time.

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