Method for creating modified design on surface, control system and robotic system

Abstract

A method of creating a modified design (60a-60d) on a surface (22a, 22b), the method comprising providing a tool (14) and an industrial robot (12) configured to perform a relative movement; providing a digital model (40) of the surface, the digital model comprising candidate contours (38) of the surface; providing a candidate path (46) for the relative movement based on the candidate profile; providing a candidate design (42a, 42b) to be created on the surface based on the candidate path; determining an actual contour (52a, 52b) of the surface; providing a modified path (56a, 56b) for the relative movement based on the actual profile; modifying the candidate design based on a deviation (58a, 58b) between the candidate path and the modified path to provide a modified design (60a-60d) to be created on the surface; and controlling the industrial robot and the tool to create a modified design on the surface using the modified path of relative movement.

Description

Technical Field

[0001] The present disclosure generally relates to the creation of designs on surfaces. Specifically, methods for creating modified designs on surfaces using tools and industrial robots, control systems for creating modified designs on surfaces, and robotic systems including industrial robots, tools, and control systems are provided. Background Art

[0002] Auto parts and many other objects can be printed using digital printing. When performing this type of digital printing, a print head with an array of nozzles can be carried by an industrial robot and used to apply paint to a surface in a controlled process to form an image on the surface. As the print head travels along a path, the print head can deposit lines of the image along the path accordingly. The print head can be controlled in this way based on the speed of the industrial robot relative to the object. Therefore, the speed can be used to determine how often the print head should print new lines of the image along the path.

[0003] DE 102010004496 A1 discloses a method for printing curved workpieces using a robot. The trajectory deviation between the actual trajectory and the target trajectory is used in real time as a correction signal for controlling the print head matrix of the print head arrangement. The corrected pixel matrix is ​​printed on the workpiece. The document points out that the decisive factor is not that the trajectory is corrected, but that the correction signal is used to directly control the inkjet nozzles arranged in the print head matrix. Summary of the invention

[0004] When printing an image on the surface of an object by digital printing, a candidate path for the print head to move relative to the surface can be generated by relying on a digital model including a candidate contour of the surface. Then, an image can be generated based on the candidate path to conform to the candidate contour.

[0005] However, in many cases, the actual profile of the surface deviates from the candidate profile. If digital printing is controlled based on the assumption that the candidate profile and the actual profile are the same, the image will be distorted when printed on the actual profile.

[0006] In order to adapt the image to the actual contour, when it is determined that the actual contour deviates from the candidate contour, the image can be regenerated based on the actual contour. However, this process is very time-consuming and reaches an unacceptable level in many embodiments.

[0007] Although DE 10 2010 004 496 A1 provides a solution for correcting printed pixels in real time when the actual trajectory deviates from the target trajectory, the document does not mention the handling of the situation where the actual contour deviates from the candidate contour.

[0008] It is an object of the present invention to provide an improved method of creating a modified design on a surface.

[0009] It is another object of the present invention to provide an improved control system for creating a modified design on a surface.

[0010] Yet another object of the present invention is to provide an improved robotic system.

[0011] These objects are achieved by a method according to the appended claim 1 , a control system according to the appended claim 10 , and a robot system according to the appended claim 11 .

[0012] The present invention is based on the recognition that when the actual contour of a surface deviates from a candidate contour from a digital model, by modifying a candidate image provided based on the digital model to provide a modified image, the modified image can be printed on the actual contour in a manner closely consistent with the manner in which the candidate image was provided relative to the candidate contour, without having to regenerate the image based on the actual contour.

[0013] According to a first aspect, a method for creating a modified design on a surface is provided, the method comprising providing a tool and an industrial robot configured to perform relative movement between the tool and the surface; providing a digital model of the surface, the digital model comprising a candidate contour of the surface; providing a candidate path for the relative movement based on the candidate contour; providing a candidate design to be created on the surface based on the candidate path; determining an actual contour of the surface; providing a modified path for the relative movement based on the actual contour; modifying the candidate design to provide a modified design to be created on the surface based on a deviation between the candidate path and the modified path; and controlling the industrial robot and the tool to create the modified design on the surface using the modified path of the relative movement.

[0014] Thus, the method accommodates deviations between the candidate contour and the actual contour by modifying the candidate design to provide a modified design. In this way, the printed image can be manipulated to compensate for path deviations caused by the actual contour not completely corresponding to the candidate contour. By modifying the candidate design to provide a modified design based on the deviation between the candidate path and the modified path, the design can effectively accommodate an actual contour that does not correspond to the candidate contour. Thus, the method includes generating a new path for relative movement based on the actual contour.

[0015] The candidate design may be modified by stretching, shortening or otherwise changing, for example in a direction parallel to the relative movement, to provide a modified design. The modification may be performed on the candidate design to provide a modified design before initiating creation of the modified design on the surface.

[0016] The determination of the actual contour may comprise measuring the actual contour. For this purpose, a line scanner may be used. The digital model may be a CAD (Computer Aided Design) model.

[0017] The tool may be of any type for creating a design on a surface. The tool may for example be a digital printing head, such as an inkjet printer.

[0018] An industrial robot may include a manipulator that is programmable in three or more axes, such as in six or seven axes. An industrial robot may carry any tool and object having a surface.

[0019] The providing of the modified path may comprise modifying the candidate path to provide the modified path.Alternatively, the modified path may be generated based on the actual contour independent of the candidate path.

[0020] The candidate design may be a candidate image. In this case, the modified design may be a modified image.

[0021] The candidate image may comprise a plurality of pixels. In this case, modification of the candidate image to provide a modified image may comprise adding one or more pixels to the candidate image or removing one or more pixels from the candidate image.

[0022] The one or more pixels may include a plurality of pixels arranged in a pixel row.

[0023] The candidate path and the modified path may be located in a common plane. The modification of the candidate design may be performed at least partially in this plane. Alternatively or additionally, the modification of the candidate design may be performed in a lateral direction of the plane.

[0024] Rows of pixels may be transverse to the plane.

[0025] The creation of the modified design on the surface may include applying a coating medium to the surface. The coating medium may be paint.

[0026] However, the method is not limited to painting. As an example, the method can also be used to form holes distributed in a specific pattern on a surface, such as by laser cutting.

[0027] The surface may be a first surface, the modified path may be a first modified path, and the modified design may be a first modified design. In this case, the method may also include providing a second surface; determining a second actual profile of the second surface; providing a second modified path for relative movement based on the second actual profile; modifying the candidate design to provide a second modified design to be created on the second surface based on a deviation between the candidate path and the second modified path; and controlling the industrial robot and the tool to create the second modified design on the second surface using the second modified path for relative movement.

[0028] According to a second aspect, a control system for creating a modified design on a surface is provided, the control system comprising at least one data processing device and at least one memory, the at least one memory having at least one computer program stored thereon, the at least one computer program comprising program code, which, when executed by the at least one data processing device, causes the at least one data processing device to perform the following steps: providing a digital model of the surface, the digital model comprising a candidate contour of the surface; providing a candidate path for relative movement between a tool and the surface based on the candidate contour; providing a candidate design to be created on the surface based on the candidate path; determining an actual contour of the surface; providing a modified path for relative movement based on the actual contour; modifying the candidate design to provide a modified design to be created on the surface based on a deviation between the candidate path and the modified path; and controlling an industrial robot and a tool to create the modified design on the surface using the modified path of relative movement.

[0029] The at least one computer program may further comprise program code which, when executed by the at least one data processing device, causes the at least one data processing device to perform or instruct the performance of any of the steps of the first aspect.

[0030] According to a third aspect, there is provided a robot system comprising an industrial robot according to the second aspect, a tool and a control system. The industrial robot, the tool and the control system may be of any type according to the present disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Additional details, advantages and aspects of the present disclosure will become apparent from the following description taken in conjunction with the accompanying drawings, in which:

[0032] Figure 1 schematically represents a side view of a robotic system including an industrial robot, a tool, and an object having a surface;

[0033] Figure 2a a side view schematically showing a candidate profile of a digital model of a surface;

[0034] Figure 2b A top view of the candidate contour is schematically shown;

[0035] Figure 3a schematically showing a candidate path for a tool and a side view of a candidate design on a candidate contour;

[0036] Figure 3b schematically showing a top view of a candidate design on a candidate outline;

[0037] Figure 4a A side view of a candidate design on the actual contour of the surface is schematically represented;

[0038] Figure 4b A top view of the candidate design on the actual outline is schematically represented;

[0039] Figure 5 a side view schematically showing a modified path of the tool;

[0040] Figure 6 The deviation between the candidate path and the modified path is schematically represented;

[0041] Figure 7a Schematically showing the modified path on the actual profile and a side view of the modified design;

[0042] Figure 7b A top view of the modified design on the actual outline is schematically shown;

[0043] Figure 8 schematically illustrates a side view of a robotic system and another object comprising a surface;

[0044] Figure 9a Schematically shows Figure 8 a side view of the candidate design on the actual contour of the surface;

[0045] Figure 9b Schematically shows Figure 9a A top view of the candidate design on the actual outline in FIG;

[0046] Fig.10 schematically showing a side view of another example of a modified path of a tool;

[0047] Fig.11 Schematically shows Fig.10 The deviation between the candidate path in and the modified path;

[0048] Fig.12a Schematically shows Fig.10 The modified path in and Figure 9a and Figure 9bA side view of a modified design of the actual profile in FIG.

[0049] Figure 12b Schematically shows Fig.12a A top view of the modified design on the actual outline of

[0050] Fig.13 schematically showing top views of additional examples of candidate designs;

[0051] Fig.14 Schematically shows the Fig.13 a top view of an additional example of a modified design of a modification of a candidate design in;

[0052] Fig.15 Schematically represents the Fig.13 a top view of an additional example of a modified design of a modification of the candidate design in; and

[0053] Fig.16 A block diagram outlining the general steps of the method is schematically represented. DETAILED DESCRIPTION

[0054] In the following, a method for creating a modified design on a surface using a tool and an industrial robot, a control system for creating a modified design on a surface, and a robotic system including an industrial robot, a tool and a control system will be described. The same or similar reference numerals will be used to represent the same or similar structural features.

[0055] Figure 1 Schematically represented is a side view of a robotic system 10. The robotic system 10 includes an industrial robot 12 and a digital printing head 14. The printing head 14 is one example of a tool according to the present disclosure.

[0056] The industrial robot 12 of this example includes a base 16 and a manipulator 18 that is movable relative to the base 16. The manipulator 18 is movable relative to the base 16 in at least three axes, such as in six or seven axes.

[0057] Figure 1 Also shown is an object 20a, which is exemplified here as a car. The object 20a includes a surface 22a, which is exemplified here as a roof surface of a car. However, the object according to the present disclosure is not limited to cars, and the surface 22a according to the present disclosure is not limited to the surface of a car body.

[0058] In this example, the object 20a is stationary, and the industrial robot 12 carries and moves the print head 14 relative to the stationary object 20a. Here, the print head 14 is arranged at the distal end of the manipulator 18. Alternatively, the print head 14 can be stationary, and the industrial robot 12 can carry and move the object 20a relative to the stationary print head 14. In any case, the industrial robot 12 is configured to perform relative movement between the print head 14 and the object 20a.

[0059] The print head 14 is configured to apply paint 24 to the surface 22a by digital printing. Paint 24 is an example of a coating medium according to the present disclosure. In this way, the print head 14 can create a modified design on the surface 22a. The print head 14 includes a plurality of nozzles 26. The nozzles 26 are individually controlled. In this example, the nozzles 26 are arranged in a matrix including rows and columns. The robot system 10 also includes a supply unit 28. The supply unit 28 is configured to supply paint 24 to the print head 14.

[0060] The robot system 10 further comprises a scanner 30 . The scanner 30 is here carried by the industrial robot 12 .

[0061] The robot system 10 also includes a control system 32. The control system 32 includes a data processing device 34 and a memory 36. The memory 36 has a computer program stored thereon. The computer program includes program code that, when executed by the data processing device 34, causes the data processing device 34 to perform or command the performance of the various steps described herein. In this example, the control system 32 controls the industrial robot 12, the supply unit 28, the print head 14, and the scanner 30.

[0062] Figure 2a A side view of a candidate contour 38 of a digital model 40 of a surface 22a is schematically shown, and Figure 2b A top view of the candidate contour 38 is schematically shown. The surface 22a and any other parts of the object 20a may be modeled, for example, using CAD to provide a digital model 40. The digital model 40 of the surface 22a including the candidate contour 38 may be provided in the control system 32. Figure 2a As shown, candidate contour 38 includes a curved portion.

[0063] Figure 3a A side view of a candidate contour 38 and a candidate image 42a thereon is schematically shown, and Figure 3b A top view of a candidate contour 38 and a candidate image 42a thereon is schematically shown. The candidate image 42a may be of various types for printing on the surface 22a. The candidate image 42a may be, for example, a stripe on top of the object 20a. The candidate image 42a includes a plurality of pixels 44.

[0064] Figure 3a Also shown is a candidate path 46 for print head 14. Candidate path 46 is the path of relative movement between print head 14 and object 20a when printing candidate image 42a on surface 22a. In this example, candidate path 46 is the path followed by manipulator 18 to move print head 14 relative to surface 22a. Candidate path 46 may, for example, be set at a fixed distance above candidate contour 38. Figure 3b , a candidate length 48a of a candidate image 42a on a candidate contour 38 is shown.

[0065] The control system 32 is configured to provide a candidate path 46 based on the candidate contour 38. The control system 32 is also configured to provide a candidate image 42a based on the candidate path 46. The candidate image 42a may be provided by modifying a source image of a planar surface based on the candidate path 46, for example.

[0066] Figure 3b Also shown is a plane 50 . The candidate paths 46 are provided here in the plane 50 . Figure 3a is a view of this plane 50.

[0067] Figure 4a schematically represents a side view of the candidate image 42a on the actual contour 52a of the surface 22a, and Figure 4b Schematically shows a top view of the candidate image 42a on the actual contour 52a. Figure 4a As shown, the physical actual contour 52a deviates from the candidate contour 38 from the digital model 40. There may be many reasons for this deviation, such as acceptable variations within a tolerance range. The actual contour 52a here has a steeper curved portion than the candidate contour 38.

[0068] To determine the actual contour 52a, the industrial robot 12 moves along the surface 22a and measures the actual contour 52a using the scanner 30. To this end, the industrial robot 12 may, for example, move along the candidate path 46. The scanner 30 measures the distance to the surface 22a for a plurality of positions along the candidate path 46. The actual contour 52a may then be determined by the distance to the surface 22a measured by the scanner 30. However, the actual contour 52a may be determined in an alternative manner.

[0069] If the frequency of the print head 14 is controlled based on the speed of the industrial robot 12 relative to the object 20a, the deviation between the actual contour 52a and the candidate contour 38 will cause the candidate image 42a to end prematurely if printed on the actual contour 52a. Therefore, the candidate image 42a printed on the actual contour 52a will be compressed compared to the candidate image 42a provided on the candidate contour 38.

[0070] like Figure 4a and Figure 4b As shown, if candidate image 42a were to be printed on actual contour 52a, candidate image 42a would have an erroneous length 54a that is shorter than candidate length 48a due to the deviation between actual contour 52a and candidate contour 38. Thus, candidate image 42a would be degraded due to the deviation.

[0071] Figure 5 A side view of a modified path 56a of the print head 14 is schematically shown. The control system 32 is configured to determine the modified path 56a based on the actual profile 52a. The modified path 56a can, for example, be set at a fixed distance above the actual profile 52a. Thus, the measured distance to the surface 22a can be used to create a new, modified path 56a for the print head 14.

[0072] Figure 6 The deviation 58a between the candidate path 46 and the modified path 56a is schematically represented. As shown, the modified path 56a deviates from the candidate path 46, here by a relatively short segment. The control system 32 can determine the deviation 58a at multiple locations along the modified path 56a.

[0073] Figure 7a Schematically shows a side view of the modified path 56a and the modified image 60a on the actual contour 52a, and Figure 7b A top view of a modified image 60a on the actual contour 52a is schematically shown. The modified image 60a is provided by the control system 32 by modifying the candidate image 42a based on the deviation 58a between the candidate path 46 and the modified path 56a. In this way, the industrial robot 12 can adapt to the deviation 58a through image compensation.

[0074] In this example, Figure 7a and Figure 7b One pixel 44 shown as unfilled has been added to candidate image 42a to provide modified image 60a. Since error length 54a is shorter than candidate length 48a, the addition of pixel 44 is performed ( Figure 4b ). Thus, candidate image 42a may be modified to provide modified image 60a such that the length of modified image 60a provided on actual contour 52a matches the length of candidate image 42a provided on candidate contour 38, as viewed from above actual contour 52a and candidate contour 38, respectively.

[0075] exist Figure 7a and Figure 7b In FIG. 6 , the modified image 60a is stretched compared to the candidate image 42a. Figure 7bAs shown, when the modified image 60a is printed on the actual contour 52a using the modified path 56a, the modified image 60a has a modified length 62a in the main extension direction of the surface 22a, which is equal to the candidate length 48a in the main direction of the surface 22a. Therefore, the modified image 60a can be printed on the actual contour 52a without distortion. That is, the appearance of the modified image 60a on the actual contour 52a corresponds to the appearance of the candidate image 42a on the candidate contour 38. The robot system 10 then performs printing of the modified image 60a on the object 20a using the modified path 56a.

[0076] Figure 8 A side view of the robotic system 10 and another object 20b including a surface 22b is schematically represented. Although both the first surface 22a and the second surface 22b are modeled by the candidate contour 38 of the digital model 40, neither the first surface 22a nor the second surface 22b completely matches the candidate contour 38. Furthermore, the first surface 22a and the second surface 22b also deviate from each other.

[0077] Figure 9a schematically represents a side view of the candidate image 42a on the second actual contour 52b of the second surface 22b, and Figure 9b Schematically shows a top view of the candidate image 42a on the second actual contour 52b. Figure 9a As shown, the physical second actual contour 52b deviates from the candidate contour 38. The second actual contour 52b here has a curved cross-section that is flatter than the candidate contour 38.

[0078] In this example, if printed on the second actual contour 52b, the deviation between the second actual contour 52b and the candidate contour 38 will cause the candidate image 42a to end too late. Therefore, compared with the provision of the candidate image 42a on the candidate contour 38, the provision of the candidate image 42a on the second actual contour 52b will be extended.

[0079] like Figure 9a and Figure 9b As shown, if candidate image 42a were to be printed on second actual contour 52b, candidate image 42a would have an erroneous length 54b that is longer than candidate length 48a due to the deviation between second actual contour 52b and candidate contour 38. Also in this manner, candidate image 42a would be degraded due to the deviation.

[0080] Fig.10A side view of the second modified path 56b of the print head 14 is schematically represented. The control system 32 is configured to determine the second modified path 56b based on the second actual profile 52b, for example in the same manner as the first modified path 56a was determined based on the first actual profile 52a.

[0081] Fig.11 The deviation 58b between the candidate path 46 and the second modified path 56b is schematically represented. As shown, the second modified path 56b deviates from the candidate path 46, here by a relatively short segment. The control system 32 can determine the deviation 58b at multiple locations along the second modified path 56b.

[0082] Fig.12a schematically shows a side view of a second modified path 56b and a modified image 60b on a second actual contour 52b, and Figure 12b A top view of a modified image 60b on the second actual contour 52b is schematically represented.The modified image 60b is provided by the control system 32 by modifying the candidate image 42a based on a deviation 58b between the candidate path 46 and the second modified path 56b.

[0083] In this example, one pixel 44 has been removed from candidate image 42a to provide modified image 60b. The removal of pixel 44 is performed because error length 54b is longer than candidate length 48a ( Figure 9b ). Also in this way, the candidate image 42a can be modified to provide a modified image 60b so that the length of the modified image 60b provided on the second actual contour 52b matches the length of the candidate image 42a provided on the candidate contour 38, as seen from above the first actual contour 52a and the candidate contour 38, respectively.

[0084] exist Fig.12a and Figure 12b In FIG. 6 , the modified image 60b is compressed compared to the candidate image 42a. Figure 12bAs shown, when the modified image 60b is printed on the second actual contour 52b using the second modified path 56b, the modified image 60b has a modified length 62b in the main extension direction of the second surface 22b, which is equal to the candidate length 48a in the main direction of the second surface 22b. Therefore, the modified image 60b can be printed on the second actual contour 52b without distortion. That is, the appearance of the modified image 60b on the second actual contour 52b corresponds to the appearance of the candidate image 42a on the candidate contour 38. The robot system 10 then performs the printing of the modified image 60b on the object 20b using the second modified path 56b. Therefore, the candidate image 42a can be processed by adding or removing pixels 44 to compensate for the inherent size difference between the first actual contour 52a or 52b and the candidate contour 38.

[0085] Fig.13 A top view of a further example of a candidate image 42 b is schematically represented. The candidate image 42 b is provided on the candidate contour 38 in the digital model 40 . Fig.13 Also shown is a candidate path 46 for the print head 14. The candidate image 42b includes a plurality of columns transverse to the candidate path 46. Fig.13 Columns 64a, 64b, and 64c are represented. Each column 64a, 64b, and 64c includes a plurality of pixels 44 that are transverse to the candidate path 46. Fig.13 , a candidate length 48b of a candidate image 42b on a candidate contour 38 is shown. Candidate images 42a and 42b are examples of candidate designs according to the present disclosure.

[0086] Fig.14 A top view of a further example of a modified image 60c is schematically represented.The modified image 60c is provided on the first actual contour 52a. Fig.14 Also shown is a first modified path 56a for print head 14. Modified image 60c is a modification of candidate image 42b based on deviation 58a between first modified path 56a and candidate path 46. Fig.14, candidate image 42b has been modified by adding column 64b2 of pixels 44 between columns 64b and 64c to provide modified image 60c. Thus, modified image 60c is extended along first modified path 56a compared to candidate image 42b. Therefore, modified image 60c has a modified length 62c along first modified path 56a that is longer than candidate length 48b of candidate image 42b along candidate path 46 to compensate for the deviation between candidate contour 38 and first actual contour 52a. Column 64b2 of pixels 44 may be inserted into candidate image 42b in which the deviation 58a between candidate path 46 and first modified path 56a is most significant. Multiple columns may be inserted in this manner.

[0087] Fig.15 A top view of a further example of a modified image 60d is schematically represented.The modified image 60d is provided on the second actual contour 52b. Fig.15 Also shown is a second modified path 56b of the print head 14. The modified image 60d is a modification of the candidate image 42b based on a deviation 58b between the second modified path 56b and the candidate path 46. Fig.15 , candidate image 42b has been modified by removing columns 64b of pixels 44 to provide modified image 60d. Thus, modified image 60d is compressed along second modified path 56b compared to candidate image 42b. Modified length 62d of modified image 60d along second modified path 56b is therefore shorter than candidate length 48b of candidate image 42b along candidate path 46 to compensate for the deviation between candidate contour 38 and second actual contour 52b. A column may be removed from candidate image 42b in which the deviation 58b between candidate path 46 and second modified path 56b is most significant. Multiple columns may be removed in this manner.

[0088] The method of modifying candidate images 42a and 42b to provide modified images 60a-60d enables the generation of modified images 60a-60d without having to modify digital model 40 and without having to generate completely new images. Modified images 60a-60d are examples of modified designs according to the present disclosure. Columns 64a, 64b, 64b2, and 64c are examples of rows according to the present disclosure. One, several, or all of columns 64a, 64b, 64b2, and 64c may also be referred to by reference numeral "64".

[0089] Fig.16A block diagram outlining the general steps of a method for printing an image on surfaces 22a and 22b is schematically represented. The method includes a step S10 of providing a print head 14 and an industrial robot 12. The method also includes a step S12 of providing a digital model 40 including candidate contours 38 of the surfaces 22a and 22b. The method also includes a step S14 of providing a candidate path 46 for relative movement between the print head 14 and the surfaces 22a and 22b based on the candidate contours 38. The method also includes a step S16 of providing candidate images 42a and 42b to be created on the surfaces 22a and 22b based on the candidate paths 46. Steps S10, S12, S14, and S16 in the first block 66 may be performed once for each digital model 40.

[0090] The method also includes a step S18 of determining the actual profiles 52a and 52b of the surfaces 22a and 22b. The method also includes a step S20 of providing modified paths 56a and 56b for relative movement based on the actual profiles 52a and 52b. The method also includes a step S22 of modifying the candidate images 42a and 42b to provide modified images 60a-60d to be printed on the surfaces 22a and 22b based on deviations 58a and 58b between the candidate paths 46 and the modified paths 56a and 56b. The method also includes a step S24 of controlling the industrial robot 12 and the print head 14 by the control system 32 to print the modified images 60a-60d on the surfaces 22a and 22b using the modified paths 56a and 56b for relative movement. Steps S18 , S20 , S22 and S24 in the second block 68 may be performed once for each object 20 a and 20 b to be painted, or once for each surface 22 a and 22 b to be painted.

[0091] This method enables the efficient printing of an existing image using the modified path 56 and avoids the time-consuming generation of a new image based on the actual contours 52a and 52b. This method helps save time and makes the robotic system 10 more flexible. The inventors have tested this method and have demonstrated that it works as described herein.

[0092] Although the present disclosure has been described with reference to exemplary embodiments, it should be understood that the present invention is not limited to what has been described above. For example, it should be understood that the size of the parts can be changed as needed. Therefore, the present invention is only limited by the scope of the attached claims.

Claims

1. A method of creating a modified design (60a-60d) on a surface (22a, 22b), the method comprising: Providing (S10) a tool (14) and an industrial robot (12), the industrial robot being configured to perform a relative movement between the tool (14) and the surface (22a, 22b); Providing (S12) a digital model (40) of the surface (22a, 22b), the digital model (40) comprising a candidate contour (38) of the surface (22a, 22b); providing (S14) a candidate path (46) for the relative movement based on the candidate contour (38); providing (S16) a candidate design (42a, 42b) to be created on the surface (22a, 22b) based on the candidate path (46); determining (S18) an actual profile (52a, 52b) of the surface (22a, 22b); providing (S20) a modified path (56a, 56b) for the relative movement based on the actual profile (52a, 52b); modifying (S22) the candidate design (42a, 42b) based on a deviation (58a, 58b) between the candidate path (46) and the modified path (56a, 56b) to provide the modified design (60a-60d) to be created on the surface (22a, 22b); as well as The industrial robot (12) and the tool (14) are controlled (S24) to create the modified design (60a-60d) on the surface (22a, 22b) using the modified path (56a, 56b) of the relative movement.

2. A method according to any one of the preceding claims, wherein the candidate design (42a, 42b) is a candidate image, and wherein the modified design (60a-60d) is a modified image.

3. The method of claim 2, wherein the candidate image comprises a plurality of pixels (44), and wherein modifying the candidate image to provide the modified image comprises adding one or more pixels (44) to the candidate image, or removing one or more pixels (44) from the candidate image.

4. The method of claim 3, wherein the one or more pixels (44) comprise a plurality of pixels (44) arranged in a row (64) of pixels (44).

5. A method according to any one of the preceding claims, wherein the candidate path (46) and the modified path (56a, 56b) lie in a common plane (50).

6. A method according to claims 5 and 6, wherein the rows (64) of pixels (44) are transverse to the plane (50).

7. The method of any one of the preceding claims, wherein creating the modified design (60a-60d) on the surface (22a, 22b) comprises applying a coating medium (24) to the surface (22a, 22b).

8. The method of any one of the preceding claims, wherein the surface (22a, 22b) is a first surface (22a), wherein the modified path (56a, 56b) is a first modified path (56a), wherein the modified design (60a-60d) is a first modified design (60a, 60c), and wherein the method further comprises: providing a second surface (22b); determining a second actual profile (52b) of the second surface (22b); providing a second modified path (56b) for the relative movement based on the second actual profile (52b); modifying the candidate design (42a, 42b) based on a deviation (58a, 58b) between the candidate path (46) and the second modified path (56b) to provide a second modified design (60b, 60d) to be created on the second surface (22b); as well as The industrial robot (12) and the tool (14) are controlled to create the second modified design (60b, 60d) on the second surface (22b) using the second modified path (56b) of relative movement.

9. A control system (32) for creating a modified design (60a-60d) on a surface (22a, 22b), the control system (32) comprising at least one data processing device (34) and at least one memory (36), the at least one memory having at least one computer program stored thereon, the at least one computer program comprising program code which, when executed by the at least one data processing device (34), causes the at least one data processing device (34) to perform the following steps: Providing (S12) a digital model (40) of the surface (22a, 22b), the digital model (40) comprising a candidate contour (38) of the surface (22a, 22b); providing (S14) a candidate path (46) for relative movement between the tool (14) and the surface (22a, 22b) based on the candidate contour (38); providing (S16) candidate designs (42a, 42b) to be created on the surface (22a, 22b) based on the candidate paths (46); determining (S18) an actual profile (52a, 52b) of the surface (22a, 22b); providing (S20) a modified path (56a, 56b) for the relative movement based on the actual profile (52a, 52b); modifying (S22) the candidate design (42a, 42b) based on a deviation (58a, 58b) between the candidate path (46) and the modified path (56a, 56b) to provide the modified design (60a-60d) to be created on the surface (22a, 22b); as well as An industrial robot (12) and the tool (14) are controlled (S24) to create the modified design (60a-60d) on the surface (22a, 22b) using the modified path (56a, 56b) of the relative movement.

10. A robot system (10) comprising the industrial robot (12) according to claim 9, the tool (14) and the control system (32).

Images