Tire mold on-line laser cleaning device and trajectory planning method

Abstract

The present disclosure provides a tire mold online laser cleaning track planning method, which comprises: photographing the cleaning area of the mold by using a 3D camera to obtain point cloud data; extracting the contour line of the mold cleaning area by using the point cloud data; and completing the tire mold online laser cleaning and track planning by using the cleaning head to move according to the contour line. The present disclosure obtains point cloud data by using a 3D camera, obtains a contour line by using point cloud data, and completes the automation of tire mold online laser cleaning by using a cleaning head to move according to the contour line. The present disclosure also provides a tire mold online laser cleaning device.

Description

Technical Field

[0001] This disclosure relates to the field of laser cleaning, and more specifically to an online laser cleaning device and trajectory planning method for tire molds. Background Technology

[0002] Tire molds are used in tire production, and the production process generates surface residues such as rubber and sulfides, necessitating regular cleaning. Traditional tire mold cleaning methods mainly involve manual handheld dry ice equipment or chemical cleaning equipment, which are inefficient, ineffective, and environmentally unfriendly. In contrast, laser cleaning offers advantages such as high efficiency, superior results, environmental friendliness, and ease of automation.

[0003] Tire mold cleaning is divided into online cleaning and offline cleaning. Online cleaning refers to cleaning the tire molds directly without removing them from the production line; offline cleaning involves removing the tire molds from the production line and transporting them to a designated cleaning station. Compared to offline cleaning, online cleaning offers advantages such as higher efficiency, faster production cycle, and no need to wait for cooling and heating. The trajectory of online laser cleaning of tire molds is very complex, and trajectory planning of the cleaning head is a crucial problem that must be solved to achieve automated cleaning. Summary of the Invention

[0004] In view of the above problems, this disclosure provides an online laser cleaning device and trajectory planning method for tire molds to achieve automated online mold cleaning.

[0005] This disclosure provides a method for online laser cleaning trajectory planning of tire molds, including: taking pictures of the cleaning area of ​​the mold using a 3D camera to obtain point cloud data; extracting the contour line of the cleaning area of ​​the mold using the point cloud data; and using the cleaning head to move according to the contour line to complete the online laser cleaning equipment and trajectory planning for the tire mold.

[0006] According to an embodiment of this disclosure, a 3D camera and a cleaning head are mounted at the end of the same robotic arm, which is mounted on an AVG trolley.

[0007] According to embodiments of this disclosure, taking pictures of the cleaning area of ​​the mold using a 3D camera to obtain point cloud data includes: moving to the mold using an AVG trolley; and taking pictures of the cleaning areas of the upper and lower molds using a 3D camera.

[0008] According to embodiments of this disclosure, extracting the contour line of the mold cleaning area using point cloud data includes: rotating and translating the registered point cloud data to the same coordinate system; identifying the cylindrical surface of the point cloud data and extracting the axis of the mold based on the cylindrical surface; generating a vertical plane containing the axis and obtaining the intersection point of the vertical plane and the point cloud data; removing redundant intersection points and connecting the remaining intersection points to form the contour line of the mold cleaning area; wherein, the redundant intersection points include points of the mold support.

[0009] According to embodiments of this disclosure, the contour lines of the mold cleaning area are extracted using point cloud data, including: S1, saving the intersection points on the contour lines from one edge toward the center of the mold to a contour array; S2, fitting the first two points in the contour array as a current fitted line; S3, detecting whether the current fitted line satisfies at least one of the following conditions: 1) the length of the current fitted line is greater than the laser linewidth; 2) and the distance from the first point in the contour array that is not involved in the fitting to the current fitted line is greater than the allowable value of laser defocusing; if yes, then the current fitted line is saved as a sub-contour line; detecting whether the contour array still has at least two points: if yes, fitting the first and second points in the contour array that are not involved in the fitting as a new current fitted line, and executing S3; if no, then ending the extraction of the contour array. If no, then detecting whether the contour array still has at least one point: if yes, then refitting a new current fitted line based on the first point in the contour array that is not involved in the fitting, and executing S3; if no, then saving the current fitted line as a sub-contour line, and ending the extraction of the contour array.

[0010] According to an embodiment of this disclosure, the cleaning head moves along a contour line, including: placing the midpoint of the cleaning head on the normal vector of the midpoint of the sub-contour line; the orientation of the cleaning head is such that the emitted laser plane is located on the plane formed by the sub-contour line and the normal vector; and rotating the cleaning head in this orientation around the mold axis for one revolution.

[0011] The second aspect of this disclosure provides an online laser cleaning device for tire molds, configured to implement the aforementioned online laser cleaning trajectory planning method for tire molds, comprising: a 3D camera for taking pictures of the cleaning area of ​​the mold to obtain point cloud data; a data processing module for extracting the contour lines of the cleaning area of ​​the mold using the point cloud data; and a cleaning head for moving according to the contour lines to complete the online laser cleaning device and trajectory planning for tire molds.

[0012] A third aspect of this disclosure provides an electronic device comprising: one or more processors; and a memory for storing one or more programs, wherein, when the one or more programs are executed by the one or more processors, the one or more processors perform the above-described online laser cleaning trajectory planning method for tire molds.

[0013] A fourth aspect of this disclosure also provides a computer-readable storage medium having executable instructions stored thereon, which, when executed by a processor, cause the processor to perform the above-described online laser cleaning trajectory planning method for tire molds.

[0014] According to the online laser cleaning trajectory planning method and online laser cleaning equipment for tire molds provided in this disclosure, point cloud data of the mold is acquired through a 3D camera, and the contour line of the mold is obtained through the point cloud data. The cleaning head then moves according to the contour line to complete the cleaning. Since data acquisition, contour line acquisition, and cleaning according to the contour line are all automated operations, the technical problems of low efficiency in offline and manual cleaning of tire molds are at least partially solved, achieving the technical effect of automated cleaning of tire molds. Attached Figure Description

[0015] The foregoing contents, as well as other objects, features, and advantages of this disclosure, will become clearer from the following description of embodiments with reference to the accompanying drawings, in which:

[0016] Figure 1 A flowchart illustrating an online laser cleaning trajectory planning method for tire molds according to an embodiment of the present disclosure is shown schematically.

[0017] Figure 2 A schematic cross-sectional view of a tire mold according to an embodiment of the present disclosure is shown.

[0018] Figure 3 This schematic diagram illustrates the upper mold cleaning trajectory and laser cleaning head pose of a tire mold according to an embodiment of the present disclosure;

[0019] Figure 4 This schematic diagram illustrates the lower mold cleaning trajectory and laser cleaning head pose of a tire mold according to an embodiment of the present disclosure;

[0020] Figure 5 A schematic diagram of the structure of an online laser cleaning device for tire molds according to an embodiment of the present disclosure is shown.

[0021] Figure 6 A block diagram schematically illustrates an electronic device suitable for implementing an online laser cleaning trajectory planning method for tire molds according to an embodiment of the present disclosure. Detailed Implementation

[0022] The embodiments of the present disclosure will now be described with reference to the accompanying drawings. However, it should be understood that these descriptions are exemplary only and are not intended to limit the scope of the disclosure. In the following detailed description, numerous specific details are set forth to provide a thorough understanding of the embodiments of the present disclosure for ease of explanation. However, it will be apparent that one or more embodiments may be practiced without these specific details. Furthermore, descriptions of well-known structures and techniques are omitted in the following description to avoid unnecessarily obscuring the concepts of the present disclosure.

[0023] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit this disclosure. The terms “comprising,” “including,” etc., as used herein indicate the presence of the stated features, steps, operations, and / or components, but do not exclude the presence or addition of one or more other features, steps, operations, or components.

[0024] All terms used herein (including technical and scientific terms) have the meanings commonly understood by those skilled in the art, unless otherwise defined. It should be noted that the terms used herein are to be interpreted in a manner consistent with the context of this specification, and not in an idealized or overly rigid way.

[0025] First, the technical terms used in this article are explained as follows:

[0026] Point cloud data: 3D point cloud data (3DPointCloud) is a data structure used to represent objects or scenes in three-dimensional space. It is a collection containing multiple three-dimensional coordinate points (X, Y, Z). These points are typically obtained by discretely sampling the surface of the actual object or scene, and therefore can be regarded as a discrete representation of the scene surface in a given coordinate system.

[0027] Two-dimensional array: refers to an array whose length and height data are composed of two-dimensional coordinate points.

[0028] Figure 1 A flowchart illustrating an online laser cleaning trajectory planning method for tire molds according to an embodiment of the present disclosure is shown, such as... Figure 1 As shown, embodiments of this disclosure provide an online laser cleaning trajectory planning method for tire molds, including: taking pictures of the cleaning area of ​​the mold using a 3D camera to obtain point cloud data; extracting the contour line of the cleaning area of ​​the mold using the point cloud data; and using a cleaning head to move according to the contour line to complete the online laser cleaning equipment and trajectory planning for the tire mold.

[0029] Through the embodiments of this disclosure, point cloud data is acquired using a 3D camera, and the point cloud data is processed to obtain the laser cleaning trajectory of the mold, i.e., the movement trajectory of the robotic arm. Then, the robotic arm, equipped with a cleaning head, moves according to the trajectory to complete the online cleaning operation of the tire mold.

[0030] Based on the above embodiments, the 3D camera and the cleaning head are mounted at the end of the same robotic arm, which is mounted on the AVG trolley.

[0031] Through the embodiments of this disclosure, the laser cleaning process is fully automated through the movement of the AVG cart, the capture of images by the 3D camera, data processing, and the cleaning head cleaning.

[0032] Based on the above embodiments, the point cloud data obtained by taking pictures of the cleaning area of ​​the mold using a 3D camera includes: moving to the mold using an AVG trolley; and taking pictures of the cleaning areas of the upper and lower molds using a 3D camera.

[0033] In this embodiment, the mold does not need to be disassembled; it is cleaned in its original position and then moved to the mold outlet by a trolley to complete the online cleaning.

[0034] Through the embodiments of this disclosure, such as Figure 2 As shown, the tire mold consists of an upper mold and a lower mold. During online cleaning, the mold remains on the production line and is not removed. The tire mold is fixed by a mold support, with the upper mold installed on top and the lower mold on the bottom, with sufficient space between them. When the mold needs laser cleaning, an AVG (Automated Guided Vehicle) cart drives to the mold location, stops at the designated position, and extends its robotic arm between the upper and lower molds. A 3D camera and a laser cleaning head are mounted at the end of the robotic arm. The 3D camera takes pictures of the surfaces of the upper and lower molds that need cleaning, obtaining point cloud data. The cleaning areas of the upper and lower molds are shown below. Figure 2 As shown, the surface of revolution is formed by rotating the internal contour line of the cross section around the mold axis. The cleaning area of ​​the upper mold includes the tire tread and the tire sidewall. In the tread section of the mold, the cleaning head needs to rotate according to the tread direction to ensure that the light is parallel to the tread direction. The cleaning area of ​​the lower mold only includes the tire sidewall.

[0035] Based on the above embodiments, the outline of the mold cleaning area is extracted using point cloud data, including: rotating and translating the registered point cloud data to the same coordinate system; identifying the cylindrical surface of the point cloud data and extracting the axis of the mold based on the cylindrical surface; generating a vertical plane containing the axis and obtaining the intersection point of the vertical plane and the point cloud data; removing redundant intersection points and connecting the remaining intersection points to form the outline of the mold cleaning area; wherein, the redundant intersection points include the points of the mold support.

[0036] Through the embodiments of this disclosure, by preprocessing the point cloud data, the points that make up the contour lines in the point cloud data are obtained from the vertical plane passing through the axis, and then connected to form the contour lines.

[0037] Based on the above embodiments, the contour lines of the mold cleaning area are extracted using point cloud data, including: S1, saving the intersection points on the contour lines from one edge towards the center of the mold to a contour array; S2, fitting the first two points in the contour array as a current fitted line; S3, detecting whether the current fitted line satisfies at least one of the following conditions: 1) the length of the current fitted line is greater than the laser linewidth; 2) and the distance from the first point in the contour array that is not involved in the fitting to the current fitted line is greater than the allowable value of laser defocusing; if yes, the current fitted line is saved as a sub-contour line; detecting whether the contour array still has at least two points: if yes, fitting the first and second points in the contour array that are not involved in the fitting as a new current fitted line, and executing S3; if no, the extraction of the contour array ends. If no, detecting whether the contour array still has at least one point: if yes, refitting the first point in the contour array that is not involved in the fitting to obtain a new current fitted line, and executing S3; if no, saving the current fitted line as a sub-contour line, and the extraction of the contour array ends.

[0038] In this embodiment, a straight line is fitted using the least squares method.

[0039] In this embodiment, since the cleaning length of the laser cleaning head at one time is equal to the laser line width, the length of the currently fitted straight line is greater than the laser line width. Therefore, the currently fitted straight line is saved as a sub-contour line, and a new fitted straight line is created.

[0040] In this embodiment, since the distance from the first point not involved in the fitting to the current fitted line is greater than the allowable value of laser defocusing, indicating that the contour line is bent, the fitting of the current fitted line is stopped, it is saved as a sub-contour line, and a new fitted line is created.

[0041] In this embodiment, if the length of the current fitted line is less than the laser linewidth and the distance from the first point not involved in the fitting to the current fitted line is less than the allowable value of laser defocusing, then the first point not involved in the fitting is added to the fitting of the current fitted line to obtain a refitted current fitted line.

[0042] Through embodiments of this disclosure, a sub-contour line that can be cleaned at a position of the laser cleaning head is obtained by fitting coordinate points in the contour array one by one.

[0043] Based on the above embodiments, the cleaning head moves according to the contour line, including: the midpoint of the cleaning head is placed on the normal vector of the midpoint of the sub-contour line; the orientation of the cleaning head is such that the emitted laser plane is located on the plane formed by the sub-contour line and the normal vector; the cleaning head is rotated around the mold axis for one revolution.

[0044] In this embodiment, Figure 3The schematic diagram illustrates the upper mold cleaning trajectory and laser cleaning head pose of a tire mold according to an embodiment of the present disclosure. In the tread pattern of the mold, the cleaning head pose needs to be rotated according to the tread pattern direction to ensure that the light is parallel to the tread pattern direction. Figure 4 The schematic diagram illustrates the cleaning trajectory of the lower mold of the tire mold and the pose of the laser cleaning head according to an embodiment of the present disclosure. In each trajectory, the laser head is perpendicular to the inner surface of the mold during cleaning. The movement trajectory of the laser cleaning head is a circular movement trajectory that rotates around the mold axis after moving to a fixed point (the midpoint of the cleaning head is placed on the normal vector of the midpoint of the sub-contour line; the orientation of the cleaning head is such that the emitted laser plane is located on the plane formed by the sub-contour line and the normal vector).

[0045] Through embodiments of this disclosure, online cleaning of the mold is achieved by moving the cleaning head along the sub-contour line and rotating it about the axis.

[0046] Based on the above-mentioned online laser cleaning trajectory planning method for tire molds, this disclosure also provides an online laser cleaning device for tire molds. The following will be combined with... Figure 5 The device is described in detail.

[0047] Figure 5 A schematic diagram of an online laser cleaning device for tire molds according to an embodiment of the present disclosure is shown. Figure 5 As shown, the online laser cleaning equipment for tire molds in this embodiment is configured to implement the above-mentioned online laser cleaning trajectory planning method for tire molds, including a 3D camera, a cleaning head, a robotic arm, an AVG trolley, and a data processing module, wherein the data processing module is not shown in the figure.

[0048] A 3D camera is used to photograph the cleaning area of ​​the mold to obtain point cloud data.

[0049] The data processing module is used to extract the contour lines of the mold cleaning area using point cloud data;

[0050] The cleaning head is used to complete the online laser cleaning equipment and trajectory planning for tire molds by moving according to the contour lines.

[0051] Figure 6 A block diagram schematically illustrates an electronic device suitable for implementing an online laser cleaning trajectory planning method for tire molds according to an embodiment of the present disclosure.

[0052] like Figure 6As shown, an electronic device 600 according to an embodiment of this disclosure includes a processor 601, which can perform various appropriate actions and processes according to a program stored in a read-only memory (ROM) 602 or a program loaded from a storage portion 608 into a random access memory (RAM) 603. The processor 601 may include, for example, a general-purpose microprocessor (e.g., a CPU), an instruction set processor and / or an associated chipset and / or a special-purpose microprocessor (e.g., an application-specific integrated circuit (ASIC)), etc. The processor 601 may also include onboard memory for caching purposes. The processor 601 may include a single processing unit or multiple processing units for performing different actions of the method flow according to an embodiment of this disclosure.

[0053] RAM 603 stores various programs and data required for the operation of electronic device 600. Processor 601, ROM 602, and RAM 603 are interconnected via bus 604. Processor 601 performs various operations of the method flow according to embodiments of the present disclosure by executing programs in ROM 602 and / or RAM 603. It should be noted that the programs may also be stored in one or more memories other than ROM 602 and RAM 603. Processor 601 may also perform various operations of the method flow according to embodiments of the present disclosure by executing programs stored in said one or more memories.

[0054] According to embodiments of this disclosure, the electronic device 600 may further include an input / output (I / O) interface 605, which is also connected to a bus 604. The electronic device 600 may also include one or more of the following components connected to the I / O interface 605: an input section 606 including a keyboard, mouse, etc.; an output section 607 including a cathode ray tube (CRT), liquid crystal display (LCD), etc., and a speaker, etc.; a storage section 608 including a hard disk, etc.; and a communication section 609 including a network interface card such as a LAN card, modem, etc. The communication section 609 performs communication processing via a network such as the Internet. A drive 610 is also connected to the I / O interface 605 as needed. A removable medium 611, such as a disk, optical disk, magneto-optical disk, semiconductor memory, etc., is installed on the drive 610 as needed so that computer programs read from it can be installed into the storage section 608 as needed.

[0055] This disclosure also provides a computer-readable storage medium, which may be included in the device / apparatus / system described in the above embodiments; or it may exist independently and not assembled into the device / apparatus / system. The computer-readable storage medium carries one or more programs that, when executed, implement the method according to the embodiments of this disclosure.

[0056] According to embodiments of this disclosure, the computer-readable storage medium may be a non-volatile computer-readable storage medium, such as including, but not limited to: portable computer disks, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), portable compact disk read-only memory (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination thereof. In this disclosure, the computer-readable storage medium may be any tangible medium that contains or stores a program that can be used by or in conjunction with an instruction execution system, apparatus, or device. For example, according to embodiments of this disclosure, the computer-readable storage medium may include ROM 602 and / or RAM 603 and / or one or more memories other than ROM 602 and RAM 603 described above.

[0057] The flowcharts and block diagrams in the accompanying drawings illustrate the architecture, functionality, and operation of possible implementations of systems, methods, and computer program products according to various embodiments of this disclosure. In this regard, each block in a flowchart or block diagram may represent a module, segment, or portion of code containing one or more executable instructions for implementing a specified logical function. It should also be noted that in some alternative implementations, the functions indicated in the blocks may occur in a different order than those indicated in the drawings. For example, two consecutively indicated blocks may actually be executed substantially in parallel, and they may sometimes be executed in reverse order, depending on the functions involved. It should also be noted that each block in a block diagram or flowchart, and combinations of blocks in a block diagram or flowchart, may be implemented using a dedicated hardware-based system that performs the specified function or operation, or using a combination of dedicated hardware and computer instructions.

[0058] Those skilled in the art will understand that the features described in the various embodiments and / or claims of this disclosure can be combined or combined in various ways, even if such combinations or combinations are not explicitly described in this disclosure. In particular, the features described in the various embodiments and / or claims of this disclosure can be combined or combined in various ways without departing from the spirit and teachings of this disclosure. All such combinations and / or combinations fall within the scope of this disclosure.

[0059] The embodiments of this disclosure have been described above. However, these embodiments are for illustrative purposes only and are not intended to limit the scope of this disclosure. Although various embodiments have been described above, this does not mean that the measures in the various embodiments cannot be used advantageously in combination. The scope of this disclosure is defined by the appended claims and their equivalents. Various substitutions and modifications can be made by those skilled in the art without departing from the scope of this disclosure, and all such substitutions and modifications should fall within the scope of this disclosure.

Claims

1. A method for online laser cleaning trajectory planning of tire molds, characterized in that, include: The cleaning area of ​​the mold was photographed using a 3D camera to obtain point cloud data; The contour lines of the mold cleaning area are extracted using the point cloud data; The cleaning head moves according to the outline to complete the online laser cleaning and trajectory planning of the tire mold; The step of extracting the contour line of the mold cleaning area using the point cloud data includes: The registered point cloud data is rotated and translated to the same coordinate system; Identify the cylindrical surface of the point cloud data, and extract the axis of the mold based on the cylindrical surface; Generate a vertical plane containing the axis, and obtain the intersection point of the vertical plane and the point cloud data; Remove redundant intersections and connect the remaining intersections to form the outline of the mold cleaning area; wherein, the redundant intersections include points of the mold support; The step of extracting the contour line of the mold cleaning area using the point cloud data includes: S1, starting from one edge of the contour line and moving towards the center of the mold, save the intersection points on the contour line to the contour array; S2, Fit the first two points in the contour array to the current fitted line; S3, Detect whether the currently fitted straight line satisfies at least one of the following conditions: 1) The length of the currently fitted straight line is greater than the laser linewidth; 2) The distance from the first point in the contour array that is not involved in the fitting to the currently fitted line is greater than the allowable value for laser defocusing; If yes, the current fitted line is saved as a sub-contour line; check whether the contour array still has at least two points: if yes, fit the first and second points in the contour array that did not participate in the fitting as a new current fitted line and execute S3; if no, end the extraction of the contour array. If not, then check whether the contour array still has at least one point: if yes, then refit the new current fitted line based on the first point in the contour array that did not participate in the fitting, and execute S3; if no, then save the current fitted line as a sub-contour line and end the extraction of the contour array.

2. The method according to claim 1, wherein, The 3D camera and the cleaning head are mounted at the end of the same robotic arm, which is mounted on an AVG trolley.

3. The method according to claim 2, wherein, The point cloud data obtained by taking pictures of the cleaning area of ​​the mold using a 3D camera includes: The AVG trolley is used to move to the mold. The 3D camera is used to take pictures of the cleaning areas of the upper and lower molds.

4. The method according to claim 1, wherein, The movement of the cleaning head along the contour line includes: The midpoint of the cleaning head is placed on the normal vector of the midpoint of the sub-contour line; the orientation of the cleaning head is such that the emitted laser plane is located in the plane formed by the sub-contour line and the normal vector; The cleaning head in the aforementioned posture is rotated one revolution around the mold axis.

5. An online laser cleaning device for tire molds, characterized in that, The system is configured to implement the online laser cleaning trajectory planning method for tire molds as described in any one of claims 1 to 4, comprising: A 3D camera is used to take pictures of the cleaning area of ​​the mold to obtain point cloud data. The data processing module is used to extract the contour lines of the mold cleaning area using the point cloud data; A cleaning head is used to perform online laser cleaning and trajectory planning of tire molds by moving the cleaning head according to the contour line; The step of extracting the contour line of the mold cleaning area using the point cloud data includes: The registered point cloud data is rotated and translated to the same coordinate system; Identify the cylindrical surface of the point cloud data, and extract the axis of the mold based on the cylindrical surface; Generate a vertical plane containing the axis, and obtain the intersection point of the vertical plane and the point cloud data; Remove redundant intersections and connect the remaining intersections to form the outline of the mold cleaning area; wherein, the redundant intersections include points of the mold support; The step of extracting the contour line of the mold cleaning area using the point cloud data includes: S1, starting from one edge of the contour line and moving towards the center of the mold, save the intersection points on the contour line to the contour array; S2, Fit the first two points in the contour array to the current fitted line; S3, Detect whether the currently fitted straight line satisfies at least one of the following conditions: 1) The length of the currently fitted straight line is greater than the laser linewidth; 2) The distance from the first point in the contour array that is not involved in the fitting to the currently fitted line is greater than the allowable value for laser defocusing; If yes, the current fitted line is saved as a sub-contour line; check whether the contour array still has at least two points: if yes, fit the first and second points in the contour array that did not participate in the fitting as a new current fitted line and execute S3; if no, end the extraction of the contour array. If not, then check whether the contour array still has at least one point: if yes, then refit the new current fitted line based on the first point in the contour array that did not participate in the fitting, and execute S3; if no, then save the current fitted line as a sub-contour line and end the extraction of the contour array.

6. An electronic device, comprising: One or more processors; Storage device for storing one or more programs. Wherein, when the one or more programs are executed by the one or more processors, the one or more processors perform the method according to any one of claims 1 to 4.

7. A computer-readable storage medium having executable instructions stored thereon, which, when executed by a processor, cause the processor to perform the method according to any one of claims 1 to 4.

Images