JP7722646B2 - Welding training system, welding training method, and program - Google Patents

Description

The present invention relates to a welding training system, welding training method, and program that support training in welding work.

With advances in virtual reality technology, various systems have been proposed that use this technology to assist in welding training. For example, Patent Document 1 discloses a welding system that includes a welding tool for performing real-world welding, a welding helmet including a face-mounted display, and a spatial tracker that tracks the welding tool and welding helmet in 3D space relative to the object to be processed. The system generates a virtual object based on information from the spatial tracker and sends the virtual object to a predetermined position on the face-mounted display. With this welding system, welding training can be performed while viewing images on the face-mounted display.

JP 2018-101124 A

In the case of the conventional welding systems described above, the welding tools (torch, welding gun, etc.) used to perform real-world welding must be operated, which creates inconveniences such as a complex device configuration. It would be convenient to use an existing VR controller instead of such special tools, but in this case, it becomes difficult to simulate in virtual space the phenomenon of the welding rod shortening during the welding process.

The present invention was made in light of these circumstances, and its primary purpose is to provide a welding training system, welding training method, and program that can support welding work training with a simple configuration.

In order to solve the above-mentioned problems, one aspect of the present invention provides a welding training system that supports training in welding work by presenting the status of welding work to a trainee in a virtual space, and is characterized by comprising: a determination unit that determines the distance between the tip of a welding rod object used in the welding work and a base material object based on the distance between the base material object and a point object for distance determination placed at the tip; a welding processing unit that performs welding processing in the virtual space if the determined distance is equal to or less than a predetermined threshold; a correction unit that reduces the axial length of the welding rod object when the welding processing is performed; a movement unit that moves the point object to the tip of the welding rod object after the correction; and a display control unit that displays an image including the corrected welding rod object and the moved point object on a display unit.

In the above aspect, the display control unit may cause the point object to be displayed transparently on the display unit.

In addition, in the above aspect, the device may further include a setting unit that sets a value for changing the axial length of the welding rod object, and the correction unit may reduce the axial length of the welding rod object based on the value set by the setting unit.

In the above aspect, if the determined distance is equal to or greater than a predetermined threshold, the welding processing unit may stop the welding process.

In the above aspect, the welding processing unit may also stop the welding process when the axial length of the welding rod object becomes equal to or less than a predetermined threshold.

One aspect of the welding training method of the present invention is a welding training method that supports training in welding work by presenting the status of welding work to a trainee in a virtual space, and is characterized in that the distance between the tip of a welding rod object used in the welding work and a base material object is determined based on the distance between the base material object and a point object for distance determination placed at the tip, and if the determined distance is equal to or less than a predetermined threshold, the welding process is performed in the virtual space, and when the welding process is performed, a correction is made to reduce the axial length of the welding rod object, the point object is moved to the position of the corrected tip of the welding rod object, and an image including the corrected welding rod object and the moved point object is displayed on a display unit.

One aspect of the present invention provides a program for causing a computer to function as a welding training device that supports training in welding work by presenting the status of welding work to a trainee in a virtual space. The program causes the computer to function as: a determination unit that determines the distance between the tip of a welding rod object used in the welding work and a base material object based on the distance between the base material object and a distance determination point object placed at the tip; a welding processing unit that performs welding processing in the virtual space if the determined distance is equal to or less than a predetermined threshold; a correction unit that reduces the axial length of the welding rod object when the welding processing is performed; a movement unit that moves the point object to the position of the corrected tip of the welding rod object; and a display control unit that displays an image including the corrected welding rod object and the moved point object on a display unit.

This invention makes it possible to accurately simulate in virtual space the phenomenon of a welding rod shortening during a welding process.

1 is a block diagram showing the configuration of a welding training system according to a first embodiment; FIG. 1 is a functional block diagram showing the configuration of an information processing device (welding training system). FIG. 10 is a diagram showing an example of a displayed screen. 10 is a flowchart showing the procedure of the operation of the information processing device (welding training system). 10 is a flowchart showing the procedure of a welding rod shortening process. FIG. 10 is a block diagram showing the configuration of a welding training system according to a second embodiment.

Preferred embodiments of the present invention will now be described with reference to the drawings. Note that the following embodiments are merely examples of methods and devices that embody the technical concepts of the present invention, and the technical concepts of the present invention are not limited to those described below. Various modifications can be made to the technical concepts of the present invention within the technical scope set forth in the claims.

(Embodiment 1)
[System configuration]
1 is a block diagram showing the configuration of a welding training system according to embodiment 1. The welding training system 100 according to this embodiment is configured by an information processing device 1.

The information processing device 1 is communicatively connected to a head-mounted display (HMD) 2, and images are displayed on a display unit 21 provided in the HMD 2 according to display control from the information processing device 1. The information processing device 1 is also communicatively connected to an input device 3 operated by the trainee, and performs various processes using information input from the input device 3.

In this embodiment, the trainee operates the input device 3 as if it were a welding device such as a welding torch while observing the image displayed on the display unit 21 of the HMD 2. The input device 3 is composed of a hand controller (VR controller) that the trainee can operate with his or her hand. This hand controller has a position sensor, and the detection results of this position sensor are output from the input device 3 to the information processing device 1. The HMD 2 also has a position sensor, and the detection results of this position sensor are output from the HMD 2 to the information processing device 1.

Next, the detailed configuration of the information processing device 1 will be described. The information processing device 1 is a computer that includes a CPU, RAM, ROM, non-volatile memory, an input/output interface, and a communication interface. The CPU of the information processing device 1 executes information processing in accordance with a program loaded from the ROM or non-volatile memory to the RAM.

The above program may be supplied to the information processing device 1 via an information storage medium such as an optical disc or memory card, or via a communications network such as the Internet or a LAN.

Figure 2 is a functional block diagram showing the configuration of the information processing device 1. The information processing device 1 includes an input information acquisition unit 11, a position calculation unit 12, a distance determination unit 13, a welding process execution unit 14, a welding rod length correction unit 15, a correction value database (DB) 16, a distance determination object movement unit 17, an image generation unit 18, and a display control unit 19. These functional units are realized by the CPU of the information processing device 1 executing information processing in accordance with a program.

The input information acquisition unit 11 acquires various pieces of information input from the input device 3 and the HMD 2. Information input from the input device 3 includes position information indicating the position of the input device 3 operated by the trainee, and selection information indicating the content selected by the trainee using the input device 3. Information input from the HMD 2 also includes position information indicating the position of the HMD 2.

The position calculation unit 12 calculates the position of each object displayed in the virtual space based on the position information input from the input device 3 and the HMD 2.

The distance determination unit 13 determines the distance between the tip of the welding rod object (described below) and the base material object. This distance is determined based on the distance between the base material object and a point object (hereinafter referred to as the "distance determination object") used for distance determination that is placed at the tip of the welding rod object.

The welding process execution unit 14 executes the welding process based on the distance between the tip of the welding rod object and the base material object determined by the distance determination unit 13. This simulates the phenomenon of flying sparks in the case of arc welding, for example.

The welding rod length correction unit 15 corrects the length of the welding rod object to simulate in virtual space the phenomenon in which the axial length of the welding rod decreases as the welding process progresses. The extent to which the length is reduced is determined by a setting value stored in the correction value DB 16.

The correction value DB16 is a database that stores the setting values (correction values) for correcting the length of welding rod objects as described above. This correction value DB16 defines correction values for each type of welding. For example, there are three defined types of welding: arc welding, semi-automatic welding, and TIG (Tungsten Inert Gas) welding, and different correction values (3.5 mm per second, 4.5 mm per second, etc.) are defined for each. Note that the correction value DB16 may be provided external to the information processing device 1, as long as it is accessible by the information processing device 1.

The distance judgment object moving unit 17 moves the distance judgment object in virtual space as the welding rod object shortens. As described below, the distance judgment object moves, following the tip of the shortened welding rod object.

The image generation unit 18 generates an image to be displayed in the virtual space based on the position of each object detected by the position calculation unit 12, whether or not the welding process is being performed by the welding process execution unit 14, the correction process by the welding rod length correction unit 15, and the movement process by the distance determination object movement unit 17.

The display control unit 19 instructs the HMD 2 to display the image generated by the image generation unit 18. As a result, the image generated by the image generation unit 18 is displayed on the display unit 21 of the HMD 2.

Figure 3 is a diagram showing an example of a screen displayed on the display unit 21 of the HMD 2. In the example shown in Figure 3, the screen 40 includes a torch object 41 corresponding to a torch, which is welding equipment, a welding rod object 42 corresponding to the welding rod attached to the torch, and a base metal object 43 corresponding to the material to be welded (base metal). In addition, the screen 40 includes a distance determination object 44, which is a point object located at the tip of the welding rod object 42, and a base end object 45, which is also a point object located at the base end.

In this embodiment, the distance judgment object 44 and the base end object 45 are displayed transparently. Therefore, the trainee cannot visually confirm the distance judgment object 44 and the base end object 45 on the screen 40. Note that the distance judgment object 44 and the base end object 45 may be displayed in a color other than transparent, but since there are no corresponding objects in real space, it is preferable to display them transparently. However, as will be described later, the distance judgment object 44 and the base end object 45 move in accordance with the tip and base end of the welding rod object 42, respectively, and therefore no particular problems arise if they are displayed in an inconspicuous color (for example, the same color as the welding rod object 42).

The torch object 41 and welding rod object 42 move within the virtual space in response to the trainee's operation of the input device 3. The welding process is then performed according to the distance between the tip of the welding rod object 42 and the base material object 43. The status of this welding work in the virtual space is displayed on the display unit 21 of the HMD 2.

[System Operation]
Next, the operation of the welding training system 100 configured as described above will be described with reference to the flowcharts shown in FIGS.
The trainee puts on the HMD 2 and checks the type of training displayed on the display unit 21 of the HMD 2. The types of training include the type of welding (arc welding, semi-automatic welding, TIG welding), the type of base material (fillet welding, V-groove), and the method of placing the base material (downward, vertical, horizontal). The trainee determines the desired type of welding, base material, and method of placing the base material, and selects it using the input device 3.

As shown in FIG. 4, when the information processing device 1 receives the selection made via the input device 3 as described above (S101), it executes a welding work training process to implement the selected type of training (S102). In this welding work training process, position information indicating the position of the input device 3 operated by the trainee and position information indicating the position of the HMD 2 worn by the trainee are continuously input to the information processing device 1. Based on this position information, the information processing device 1 calculates the positions of each object in virtual space, such as the torch object 41, welding rod object 42, base material object 43, distance judgment object 44, and base end object 45, and generates an image based on the calculation results. The image generated in this manner is transmitted from the information processing device 1 to the HMD 2 and displayed on the display unit 21 of the HMD 2.

When the welding rod object 42 moves in virtual space in response to the trainee's operation, the positions of the tip and base ends of the welding rod object 42 change accordingly. At this time, the information processing device 1 also changes the positions of the distance judgment object 44 and base end object 45 in accordance with the change in the positions of the tip and base end of the welding rod object 42. By performing this processing, the distance judgment object 44 and base end object 45 can be maintained in their positions at the tip and base end of the welding rod object 42, respectively.

During the above welding work training process, a welding rod shortening process is executed to simulate in virtual space the phenomenon in which the axial length of the welding rod shortens as the welding process progresses. Details of this process will be described later.

After a certain amount of training has been conducted through the welding work training process in step S102, the information processing device 1 determines whether or not to end the training (S103). For example, if the trainee uses the input device 3 to instruct the end of training, or if the number of training sessions or the length of time have reached a predetermined number of sessions or time, it is determined that the training has ended (YES in S103) and the process ends. On the other hand, if it is determined that the training will continue rather than end (NO in S103), the information processing device 1 returns to step S102 and the training is conducted again.

Next, the welding rod shortening process will be described in detail with reference to Figure 5. Note that this welding rod shortening process is repeatedly performed during the welding work training process described above.

The information processing device 1 calculates the distance between the distance determination object 44 placed at the tip of the welding rod object 42 and the base material object 43 (S201), and determines whether the distance is equal to or less than a preset threshold value T1 (S202). The threshold value T1 is set to a value such as 0.1 mm, for example.

If it is determined in step S202 that the distance calculated is equal to or less than the threshold value T1 (YES in S202), the information processing device 1 executes the welding process (S203). In this manner, in this embodiment, the welding process is executed when the distance between the distance judgment object 44 and the base material object 43 is equal to or less than a certain value. This is because this distance can be considered to be the distance between the tip of the welding rod object 42 and the base material object 43. After the welding process is executed in this manner, the welding rod object 42 is shortened and the distance judgment object 44 is moved, as required for the welding process.

The information processing device 1 first executes a correction process to reduce the axial length of the welding rod object 42 in accordance with the correction value specified in the correction value DB 16 (S204). For example, if arc welding is selected for the current training and the correction value DB 16 specifies a correction value of 3.5 mm per second for arc welding, the information processing device 1 reduces the axial length of the welding rod object 42 by moving the tip end of the welding rod object 42 axially toward its base end at 3.5 mm per second.

Next, the information processing device 1 moves the distance judgment object 44 so that it follows the tip of the welding rod object 42 shortened as described above (S205). More specifically, the information processing device 1 calculates the three-dimensional position coordinate pos_e1_new of the distance judgment object 44 in the virtual space after the length of the welding rod has been corrected using the following equation 1, and moves the distance judgment object 44 to the calculated position coordinate pos_e1_new.
pos_e1_new = pos_e1 - shorten_distance×(pos_e1 - pos_e2)/edge_distance...Formula 1
where pos_e1 is the current three-dimensional position coordinates (e1.x, e1.y, e1.z) of the distance determination object 44, and pos_e2 is the current three-dimensional position coordinates (e2.x, e2.y, e2.z) of the base end object 45. Also, shorten_distance is the correction value used in correcting the length of the welding rod object 42 in step S204. Furthermore, edge_distance is the distance between pos_e1 and pos_e2, and is calculated by the following equation 2.

After correcting the length of the welding rod (S204) and moving the distance determination object 44 (S205) as described above, the information processing device 1 returns to step S201 and repeats the subsequent processes.

If it is determined in step S202 above that the distance is greater than threshold T1 (NO in S202), the information processing device 1 determines whether the distance is equal to or less than a preset threshold T2 (S206). Note that threshold T2 is greater than threshold T1, and a value such as 10.0 mm is set as threshold T2.

If it is determined in step S206 that the distance is equal to or greater than threshold value T2 (YES in S206), the information processing device 1 stops the welding process that has already been performed (S207). In this manner, in this embodiment, the welding process is stopped when the distance between the distance determination object 44 and the base material object 43 becomes equal to or less than a certain value. This is because this distance can be considered to be the distance between the tip of the welding rod object 42 and the base material object 43. The information processing device 1 then returns to step S201 and repeats the subsequent processes.

Furthermore, if it is determined in step S206 that the distance is smaller than threshold T2 (NO in S206), the information processing device 1 calculates the length of the welding rod object 42 (S208). This length is obtained as the distance between pos_e1 and pos_e2, i.e., edge_distance.

Next, the information processing device 1 determines whether the length of the welding rod object 42 is equal to or less than a preset threshold T3 (S209). Note that the threshold T3 is set to a value (e.g., 20.0 mm) that indicates the length of the welding rod at which it is not appropriate to continue the welding process.

If it is determined in step S209 that the length of the welding rod object 42 is equal to or less than threshold value T3 (YES in S209), the information processing device 1 stops the welding process that has already been performed (S207). In this manner, in this embodiment, the welding process is stopped when the length of the welding rod object 42 becomes inappropriate for the welding process. Thereafter, the information processing device 1 returns to step S201 and repeats the subsequent processes.

On the other hand, if it is determined in step S209 that the length of the welding rod object 42 is greater than threshold T3 (NO in S209), the information processing device 1 returns to step S201 without stopping the welding process, and repeats the subsequent processes.

By repeatedly executing the welding rod shortening process described above, the welding process is started or stopped depending on the distance between the distance determination object 44 and the base material object 43, and when the welding process is executed, the welding rod object 42 is corrected to be shorter. This makes it possible to simulate in virtual space the phenomenon of the welding rod shortening during the welding process.

If a method for directly determining the distance between the tip of the welding rod object 42 and the base material object 43 is adopted, rather than using the distance determination object 44, the tip is an area made up of multiple points, so there is a problem in that it is unclear which of the points making up the tip should be used to determine the distance between the base material object 43 and the base material object 43. By introducing a distance determination object 44 for determining the distance to the base material object 43, as in this embodiment, this problem can be avoided.

Furthermore, because the distance judgment object 44 is a separate object from the welding rod object 42, if the welding rod object 42 becomes shorter as the welding process is performed, the distance between the tip of the welding rod object 42 and the base material object 43 cannot be appropriately determined unless the distance judgment object 44 is moved accordingly. Therefore, in this embodiment, the distance judgment object 44 is moved to follow the tip of the welding rod object 42 that has moved toward the base end due to the shortening. This makes it possible to position the distance judgment object 44 at the tip of the shortened welding rod object 42, and therefore the distance judgment object 44 can be used to appropriately determine the distance between the tip of the welding rod object 42 and the base material object 43.

(Embodiment 2)
In the second embodiment, the information processing device and HMD in the first embodiment are configured as a single device. Fig. 6 is a block diagram showing the configuration of a welding training system in the second embodiment. As shown in Fig. 6, welding training system 200 in this embodiment is configured as an HMD, and includes information processing unit 201 and display unit 202. Information processing unit 201 corresponds to information processing device 1 in the first embodiment, and display unit 202 corresponds to display unit 21. Furthermore, welding training system 200 is communicably connected to input device 3 in the same manner as in the first embodiment.

The information processing unit 201 executes the same processing as the information processing device 1 in embodiment 1, and causes the display unit 202 to display the status of the welding work in the virtual space. As a result, the present embodiment achieves the same effects as embodiment 1.

(Other embodiments)
In each of the above embodiments, a head-mounted display is used, but the present invention is not limited to this, and other wearable devices such as a glasses-type display may also be used.

REFERENCE SIGNS LIST 1 Information processing device 11 Input information acquisition unit 12 Position calculation unit 13 Distance determination unit 14 Welding process execution unit 15 Welding rod length correction unit 16 Correction value database 17 Distance determination object movement unit 18 Image generation unit 19 Display control unit 2 Head-mounted display 21 Display unit 3 Input device 41 Torch object 42 Welding rod object 43 Base material object 44 Distance determination object 45 Base end object 100, 200 Welding training system

Claims (3)

A welding training system that supports training of welding work by presenting a welding work situation to a trainee in a virtual space,
a determination unit that determines a distance between a tip end of a welding rod object in the virtual space used for the welding work and a base material object based on a distance between the base material object and a point object for distance determination that is arranged at the tip end of the welding rod object in the virtual space ;
a welding processing unit that executes welding processing in the virtual space when the determined distance is equal to or less than a predetermined threshold. A welding training method for supporting training of welding work by presenting a welding work situation in a virtual space to a trainee, comprising:
determining a distance between a tip end of a welding rod object in the virtual space used for the welding work and a base material object based on a distance between a point object for distance determination that is located at the tip end of the welding rod object in the virtual space and the base material object;
A welding training method, characterized in that, when the determined distance is equal to or less than a predetermined threshold, a welding process is performed in the virtual space. A program for causing a computer to function as a welding training device that supports training in welding work by presenting a welding work situation to a trainee in a virtual space,
a determination unit that determines a distance between a tip end of a welding rod object in the virtual space used for the welding work and a base material object based on a distance between the base material object and a point object for distance determination that is arranged at the tip end of the welding rod object in the virtual space ;
and a program for causing the computer to function as a welding processing unit that performs welding processing in the virtual space when the determined distance is equal to or less than a predetermined threshold value.