EP1911264A2

EP1911264A2 - Method and device for decorating walls

Info

Publication number: EP1911264A2
Application number: EP06763955A
Authority: EP
Inventors: Laurent Tidona
Original assignee: La peintures monumentales Sarl Ste
Current assignee: La peintures monumentales Sarl Ste
Priority date: 2005-06-28
Filing date: 2006-06-28
Publication date: 2008-04-16
Also published as: WO2007000468A3; WO2007000468A2

Abstract

The invention relates to a method according to which: the contours of an image representing the decoration to be carried out are defined, and at least some of the contours are tracked with a narrow light beam projected onto the support to be decorated. Preferably, the light beam consists of a laser beam, and an image scanner, a means for extracting contours of the scanned image, and a remote control are used. Furthermore, according to said method: the support is modelled in three dimensions; an image to be drawn according to the model of the support is calculated for at least two tracing appliance sites; and at least some of the contours of the image calculated corresponding to the site are traced on the support to be decorated, from each site, using at least one tracing appliance. In one form of embodiment, each step for calculating an image consists of a step for determining the position of at least two sites of tracing appliances, and a step for locating a point on the support.

Description

METHOD AND DEVICE FOR REALIZING MONUMENTAL DECORATIONS

The present invention relates to a method and a device for making monumental decorations. It applies, in particular, to the drawing of drawings on exterior walls of buildings, for artistic, informative or advertising purposes. One of the difficulties, when making a monumental painting, is to respect the proportions of the different painted areas and thus, not to distort the objects to be represented. Not being able to take a step back from the support, the painter who wishes to first draw his drawing is lost on the scaffolding. To date, the most commonly used technique is that of the grid: the drawing to be reproduced is squared on paper, one then squares the support with a homothetic grid, one postpones the intersections of the drawing with the grid with the necessary factor of enlargement and we try to reproduce the drawing from these intersections. This technique, long, complex and imprecise has reached its limits today and it is limited to experienced people. One of the aims of the present invention is to allow everyone to trace on monumental support. Drawing tracing methods, such as that presented in the document, are known.

GB 2 200 596, which describes a method and a kit for producing paints, the outline of subjects being drawn in fugitive ink dissolved in contact with the paint. This process does not solve the problem of respecting the proportions explained above.

The process described in document US Pat. No. 2,744,349 is known for the painting and the reproduction of paint by contour extraction, attribution to the areas delimited by the contours, color references and printing of contours and references, which requires the implementation of a printer, which is not compatible with the production of monumental painting or imposes a technical complexity and a high realization cost.

The method described in document EP 0 968 845 is known for the reproduction of a painting by decomposition of the image file into image elements, adaptation of the measurements of elements, alignments and perspectives to the shapes and geometry of the wall. decorate and assemble these image elements into a new image. A print transfers this new image onto a base material before it is mounted on the wall.

GB 2 270 812 and US 4 958 237 disclose methods for printing giant, piece-wise images. Here again, the complexity and the cost of implementing this method are very important and disabling.

It is also observed that all the printing-based processes require the use of inks or pigments which do not have the characteristics of resistance to weather, solar radiation and time, sufficient in the field of the building. The present invention aims to remedy these disadvantages. For this purpose, the present invention aims, in a first aspect, a method for producing monumental decorations, characterized in that it comprises:

a step of defining contours of an image representing the decoration to be produced and

- A tracking step, with a narrow light beam projected onto the support to be decorated, at least a portion of said contours. Thanks to these arrangements, the decorator first traces the contours of the decoration to be made, by applying a visible trace, for example with chalk or paint, following the pattern provided by the position of the luminous point of impact of the light beam on the surface to decorate. He can then, if necessary, put in color the drawing, by painting the surfaces delimited by the outlines preliminary drawn.

According to particular characteristics, during the tracking step, the light beam consists of a laser beam. Thanks to these provisions, the method can be implemented even when the ambient light is intense since the point of impact of the laser is very bright. In addition, the precision of the drawing is increased thanks to the fineness of this point of impact. According to particular features, the tracking step includes a step of remote control of the displacement of the source of the light beam. With these features, the painter can stop tracing, resume where he stopped, go back and / or reproduce a tracking sequence.

According to particular features, the remote control step includes a step of controlling the tracking speed of the portion of the contour followed. With these provisions, the painter can slow down the tracking speed when the shape of the part of the contour followed becomes complex.

According to particular features, the method as briefly described above comprises a step of digitizing a representation of the decoration to be produced by image scanner. Thanks to these provisions, the capture of the image to be made is simplified.

According to particular features, the method as briefly described above comprises an image extraction step with contour extraction in a digital representation of the decoration to be produced.

According to particular features, the method as briefly described above comprises a step of determining positions of reference points on the support and an anamorphosis correction step. Thanks to these arrangements, even if the source of the light beam is not in an orthogonal axis to the plane of the support, the plot can be homothetic to the representation of the decoration to be made. Thanks to these provisions too, if the support is not flat, the defect of non-flatness can be corrected. According to particular features, the method as briefly described above comprises a step of determining the radius of curvature of the outline to be drawn and, during the tracking step, the speed of movement of the light beam on the support is function said radius of curvature. Thanks to these provisions, the areas of the contour most difficult to reproduce, where the radius of curvature of the contour is small, can be traced more slowly, the movement of the light beam then being slowed down.

According to a second aspect, the present invention relates to a device for producing monumental decorations, characterized in that it comprises: a means for defining contours of an image representing the decoration to be produced and - Means for projecting a narrow light beam on the support to be decorated, and moving the position of said light beam to track at least a portion of said contours with said light beam.

According to particular features, the projection means comprises a source of a laser beam.

According to particular features, the device as briefly described above includes a remote control.

According to particular characteristics, said remote control is adapted to control the tracking speed of the part of the contour followed. According to particular features, the device as briefly described above comprises an image scanner.

According to particular features, the device as briefly described above comprises an image processing means adapted to extract contours in a digital representation of the decoration to be produced. According to particular features, the device as briefly described above comprises means for determining positions of reference points on the support and anamorphosis correction means.

According to particular features, the device as briefly described above comprises means for determining the radius of curvature of the contour to be traced and the means of displacement of the light beam on the support is adapted to move the light beam on the support according to said radius of curvature.

According to particular features, the moving means comprises at least one stepper motor. Thanks to these arrangements, the orientation of the light beam can be very precisely controlled. Using the method and device as described, the decorator first traces the contours of the decoration to be made, applying a visible trace, for example chalk or paint, following the path provided by the position of the luminous point of impact of the light beam on the surface to be decorated. He can then, if necessary, put in color the drawing, by painting the surfaces delimited by the outlines preliminary drawn. However, two situations are problematic:

- In the case of supports of high height, access to which is by scaffolding, scaffolding obstructs the path of the light beam;

- In the case of supports whose several faces or the complete periphery, for example cylindrical, must be decorated. The present invention according to another of its aspects aims to remedy these disadvantages.

For this purpose, the present invention aims, in this other aspect, a method for producing monumental decorations on a support, which comprises:

a step of modeling the support in three dimensions; for at least two locations of projection apparatus, a step of calculating an image to be drawn according to the model of the medium and,

a step of tracking, on the support to be decorated, from each location, with at least one projection apparatus, at least part of the outlines of the calculated image corresponding to said location.

Thanks to these arrangements, even if there is an obstacle between the projection apparatus and the support or in the event of difficulty in positioning a projection apparatus so that it can follow the outline of the entire image , For example on a cylindrical support, the multiplicity of equipment locations and the corresponding image calculation allows the decorator to trace the contours of the decoration to be made, on the entire support.

According to particular characteristics, each step of computing an image comprises:

a step of determining the position of at least two locations of projection apparatus and

a step of locating a point on the support. Thanks to these provisions, the complex forms of media are easily taken into account.

According to particular features, during the step of determining the position of at least two locations of projection apparatuses, positioning equipment is used which refers to radio signals. According to particular characteristics, during the step of determining the position of at least two locations of projection apparatus, an inclinometer is used.

According to particular characteristics, during the step of determining the position of at least two locations of projection apparatuses, a range finder is used.

According to particular characteristics, during the tracking step, the contour is followed with a narrow light beam projected onto the support to be decorated from each location. With these provisions, the decorator only has to follow the movement of the point of impact of the light beam on the support to trace the contour.

According to particular characteristics, during the tracking step, the light beam consists of a laser beam. Thanks to these provisions, the method can be implemented even when the ambient light is intense since the point of impact of the laser is very bright. In addition, the precision of the drawing is increased thanks to the fineness of this point of impact.

According to particular characteristics, during the tracking step, contours are simultaneously monitored with at least two projection devices positioned in at least two of said locations, the projection apparatuses following an identical path on the support, from different locations. Thanks to these provisions, the outline of the contour can be carried out in a single step.

According to particular characteristics, during the tracking step, the projection devices are synchronized so that they follow, at each moment, the same part of the contour. According to particular characteristics, during the tracking step, the contour tracking is successively carried out with a projection apparatus positioned successively at said locations. With these provisions, a single projection device is sufficient.

According to particular characteristics, during the step of modeling the support in three dimensions, it implements the support planes.

According to particular characteristics, during the step of modeling the support in three dimensions, a 3D scanner is used.

According to particular characteristics, during the step of modeling the three-dimensional support, a narrow light beam is used, the position of which is controlled to correspond to points marked on the support.

According to particular characteristics, the tracking step includes a step of remote control contour tracking. With these features, the painter can stop tracing, resume where he stopped, go back and / or reproduce a tracking sequence.

According to particular features, the tracking step includes a step of implementing at least one camera and a means for viewing an image facing the eyes of the user.

According to a second aspect, the present invention relates to a device for producing monumental decorations on a support, which comprises:

means for modeling the support in three dimensions; a means for calculating, for at least two locations, an image to be drawn according to the model of the support and

- At least one projection apparatus adapted to follow, on the support to be decorated, from each location, at least a portion of the contours of the calculated image corresponding to said location. The advantages, aims and characteristics of the device as succinctly described above being similar to those of the method as succinctly described above, they are not recalled here.

The advantages, aims and characteristics of the device as succinctly described above being similar to those of the method as succinctly described above, they are not recalled here.

Other advantages, aims and features of the present invention will emerge from the description which follows, made for an explanatory and non-limiting purpose with reference to the appended drawing in which:

FIG. 1 represents, schematically, a particular embodiment of the device that is the subject of the present invention,

FIG. 2 schematically represents, in the form of a logic diagram, the steps implemented in a particular embodiment of the method that is the subject of the present invention,

FIG. 3 represents, schematically, a particular embodiment of a means for displacing a narrow light beam incorporated in the device illustrated in FIG. 1; FIG. 4 represents, schematically, a first particular embodiment of a device that is the subject of the present invention, for implementing the method according to the second embodiment,

FIG. 5 represents, schematically, a second embodiment of the device that is the subject of the present invention, for implementing the method according to the second embodiment,

FIG. 6 schematically represents a third particular embodiment of the device which is the subject of the present invention, for the implementation of the method according to the second embodiment, FIG. 7 schematically represents a fourth particular embodiment. of the device according to the present invention, for implementing the method according to the second embodiment,

FIG. 8 represents, in the form of a logic diagram, the steps implemented to implement a particular embodiment of the method according to the second embodiment, FIG. 9 represents, schematically, the image distortion to be compensated for. a cylindrical support.

The device and method illustrated in Figures 1 and 9 are intended to achieve any type of drawing, logos, advertising, information or artistic drawings, for example, on any type of support, concrete or cladding, for example. The principle implemented involves digitizing the image or its contours with a scanner, extracting the contours of the image, if necessary, to place a projection and displacement device with a narrow light beam, preferably a laser beam, at a distance from the support and to start the tracing, the projection and displacement apparatus making the enlarged contours of the image to be reproduced follow at the point of impact of the light beam on the support. The operator has a remote control to control the operation of the projection apparatus and displacement and materializes the contours, for example with chalk, following the movement of the light beam on the support. Once the contours of the drawing materialized, the painter or painters can perform the coloring of the decoration to be made, using paints.

FIG. 1 shows a support to decorate 50 having reference points 51 to 56, a computer 100 connected to a scanner 110 and having a computer-assisted drawing software 120, a contour extraction software 130 , contour curvature radius determination software 135, anamorphosis correction software 140, projected image sphericity correction software 145 and support non-flatness correction software 150, control software stepper motors 160, two step motors 170 and 175, a mirror 180 and a laser diode 190.

A remote control 200 remotely controls the operation of the device represented in FIG. 1 and, in particular, the movement of the stepper motors, the memorization of their positions by the computer 100, the processing of these data, the shutdown, the recovery, the direction and the speed of displacement of the laser beam on the support 50. Although there is shown in Figure 1, a set of means implemented in a particular embodiment of the device object of the present invention, these means may be in turn interconnected. For example, since the scanner 110 and the stepper motors 170 and 175 are not generally used at the same times, they can be alternately connected to the computer 100. Similarly, FIG. device comprising only a central processing unit, that of the computer 100, but, in other embodiments, a central unit connected to the scanner 110 processes the digitized data and provides an outline file to be traced to another central unit connected to stepper motors 170 and 175. This breaks the device into two units, one fixed and the other movable and light, which can easily be installed on the paint site.

The support to be decorated 50 may be plane or not, plan by part, concave and / or convex by parts. As explained below, the anamorphosis correction software 140 and the non-flatness correction software of the support 150 make it possible to correct these irregularities in order to carry out decorations in which these irregularities are compensated, depending on the location of the where we want the decoration to appear homothetic to the initial image. In FIG. 1, the reference points 51 to 54 define the corners of the portion of the decoration to be made that are in a first plane and the points 53 to 56 define the corners of the portion of the decoration to be made that are located in a second plane.

The computer 100 is, for example, a general purpose computer, for example of PC type (for personal computer or personal computer). It is equipped with a processor, mass memories, RAMs, a keyboard, a mouse, interface connectors with the other elements of the device, remote radio communication means for receiving the signals 200 and a screen, these elements not being shown for the sake of clarity in Figure 1. The scanner 110 is of known type and is adapted to provide digital signals representative of an object or of an image placed next to its window, according to known techniques.

The computer-assisted design software 120 allows a graphic designer to make or correct a drawing to be reproduced on the support 50. In one embodiment without correction of anamorphosis or non-flatness, it is possible to implement a software of drawing providing a Bitmap file (in which at each point of the image is associated several main color intensity values), contour extraction software that provides a bitmap image and vectorization software, which transforms an image binary contours into a set of vectors. In another embodiment, still without correction of anamorphosis and non-flatness, it is possible to implement a vectorial drawing software.

Examples of ways of proceeding allowing the implementation of these embodiments are given below:

In the first, we draw on paper, we scan the drawing using a scanner, to obtain a bitmap image, we extract the contours of the image using a drawing software (for example Photoshop, registered trademark), we convert the image into a vector (that is to say into a series of vectors, and of Béziers curves) then we convert the image, for example into an HPGL file ( suite of linear vectors) or SVG (acronym for scalable vector graphies for scalable vector graphics) (vector sequences and Bezier curves). In the second, the drawing is done directly with drawing software that provides a bitmap file, and then performs the following operations exposed in the first example.

In the third, the drawing is done directly with a vector drawing software, for example Corel Draw (registered trademarks) or Adobe Illustrator (registered trademarks), and the drawing is saved in HPGL format. Note that a bitmap is an image composed of a series of pixels recorded one after the other, while a vector image is a series of points, vectors, curves that make up the drawing. To change from bitmap format to vector format, there is software that does the calculation, for example Corel offers in its Corel Draw package the Corel OCR Trace software that does this calculation or software such as Autotrace (registered trademark). To go from vector format to HPGL format, Corel Draw does it directly, software used for architects such as SDI CGM Convert (trademarks) are specialized in transforming files, or you can use software like Transfig (registered trademark) .

The contour extraction software 130 is adapted to extract contours in the image provided by the scanner 110 or by the drawing software 120, according to known techniques.

It is observed that when the drawing software directly provides a binary file, in which each picture point can only take two values, black or white, or the scanned image is binary, the extraction of outlines can be optional. .

The contour curvature radius determination software 135 is adapted to determine the average radius of curvature of a part of the contour, for example of a length of one meter, according to known techniques. The anamorphosis correction software 140 is adapted to correct the distortions due to the decentering of the light source, relative to the axis of the support normal to the support and passing through the center of the decoration to be produced, according to known techniques. The non-flatness correction software of the support 150 is adapted to compensate for non-flatness of the support, as a function of reference points, for example by considering the support as a piece-wise plane, the reference points representing the intersections of the pieces of plans considered.

For spherical correction of the projected image, the projected image sphericity correction software 145 performs one of two detailed initialization processes, by way of example, below.

In the first, we find the point of rotation by calculation. In order to calculate this point of rotation, the following calibration is carried out, possibly in the manufacture of the device. We draw a large square, for example 4 meters side, on a flat support. The light source illustrated in FIG. 3 is placed opposite this square, substantially along the axis of symmetry. square. Using a graphical interface, the movement of the step motors of the mirror is controlled so that the point of impact of the laser beam is positioned successively on the corners of the square and on the media of its sides. This gives a table that includes the physical coordinates of the points and their coordinates in steps of each engine. This table provides the angular proportionality coefficients.

In the second process, the image is adjusted to correct the sphericity of the projection (each step of a motor representing a distance traveled on the plane support which depends on the angle of incidence of the light beam on the support). For this purpose, an inverse deformation of the optical deformation is applied to the image, by implementing conventional trigonometric calculations, knowing the positions of the stepping motors which correspond to an incidence perpendicular to the support, the angle traveled at each not of each of the engines and the table evoked above.

The stepper motor control software 160, the two stepper motors 170 and 175, the mirror 180 whose horizontal orientation is directly a function of that of the rotor of the motor 170 and whose vertical orientation is directly a function of that the rotor of the motor 175, and the laser diode 190 whose light beam is oriented towards the mirror 180, are of known type and are therefore not detailed here.

The remote control 200 transmits signals, preferably wireless, according to the instructions provided by the user, for example by means of a keyboard. The remote control 200 may, for example, take the form of a personal digital assistant or PDA (for personal digital assistant) or a mobile phone and can implement the Bluetooth and / or Wifi communication standards.

As seen in FIG. 2, during a step 205, the user starts scanning an image that he wishes to reproduce on a support 50, by implementing the scanner 110. step 210, the scanned image is received by the computer 100 and stored. During a step 215, the user edits the scanned image to possibly modify it. During a step 220, the user starts the contour extraction of the edited image and the computer 100 extracts the contours of the scanned image to provide a binary image. During a step 225, the user edits the contour image, for example to remove isolated points. During a step 230, the computer transforms the contours into a succession of segments, for example into a file in HPGL format (acronym for Hewlett-Packard Graphics Language, for, in English graphic language Hewlett-Packard, registered trademark) it's a standard format also called ". plt "because it is mainly used for plotters. During this same step 230, the computer associates with each segment a tracking speed factor, a factor defined as an increasing function of the average radius of curvature of the segment considered, radius of curvature that the computer determines in a conventional manner, said speed that can be bounded by a lower value and a higher value. During a step 235, the user positions the light source, comprising the laser diode, the mirrors and the stepper motors, next to the support where the decoration must be postponed. During a step 240, with the remote control, the user controls the displacement of the point of impact of the laser beam on the support to make it reach, successively, different reference points on the support, for example, for a support plan, four reference points embodying the four corners of a rectangle exinscrit of the decoration to be reproduced and, for a support piece by piece, reference points of the perimeter of the decoration to achieve. Whenever one of the reference points is reached, with the remote control, the user causes the storing of the position of the stepper motors by the computer 100, step 245.

Once the positions in question of the stepper motors have all been stored, the computer 100 determines the compensations to be made to compensate for the anamorphosis and the sphericity of the projection, that is to say the deformations of the projected images resulting from the eccentricity of the light source relative to the axis perpendicular to the support planes and passing through the middle of the decoration corresponding thereto and the spherical projection, during a step 250. During a step 255, the user controls the beginning of contour tracking by the laser beam on the support. During a step 260, the computer controls the stepper motors to successively follow the laser beam, on the support, the contours of the compensated image, at a speed defined by default, for example the last speed used by the user multiplied by the velocity factor function of the radius of curvature corresponding to the segment being traced.

As a variant, the speed of the beam on the support is also a function of the angle of incidence of the beam on the support so that the drawing of the same succession of segments is done at the same speed regardless of this angle of incidence. .

In the steps below, an example of use of the system, via the remote control, is described.

During a step 265, the computer 100 determines whether the user has remotely controlled a movement stop. If yes, during a step 270, the computer 100 commands the stopping movement of the stepper motors and returns to step 265. Otherwise or when the user remote control a resumption of the displacement, during in a step 275, the computer 100 determines whether the user has remotely controlled a change in the speed of the displacement of the beam on the support. If yes, during a step 280, the computer 100 modifies the speed of movement of the beam according to the received instructions and goes to step 285. Otherwise, during step 285, the computer 100 determines whether the user remotely controlled a resumption of the plot. If yes, during a step 290, the computer controls the stepper motors to redo the beam to the last five traced segments (the number of five being configurable) and returns to step 285. Otherwise, or when the the user controls the resumption of tracking, in a step 295, the computer 100 determines whether the user has remotely controlled a change of direction of movement. If so, during a 300, the computer controls the stepper motors to reverse the contour tracking direction. If not, or at the end of step 300, the computer returns to step 260 until all edges of the image have been processed. During the steps 260 to 300, the user traces, for example with chalk, the contour visualized by the displacement of the laser beam on the support. Once all the contours have been followed, the user can color the decoration, using the contours shown by the chalk lines. As a variant, during a step preceding step 260, the user spreads, on the support, a photosensitive layer at the wavelength of the laser beam, preferentially invisible, the displacement of the laser beam on the medium that varies locally the appearance of this photosensitive layer.

The device and the method according to the second embodiment are always intended to produce any type of drawings, logos, advertisements, information or artistic drawings, for example, on any type of support, concrete or cladding, for example. The method used comprises the following steps:

to digitize the image or its contours with a scanner,

to extract the contours of the image, if necessary, to place two projection and displacement devices of a narrow light beam, preferably a laser beam, at a distance from the support and at a distance between them;

launching the tracing, the projection and displacement devices which follow, at the point of impact of the light beam on the support, the enlarged contours of the image to be reproduced, in a coordinated manner, as described below. Preferably, the operator has a remote control for controlling the operation of the projection and displacement apparatus and materializes the contours, for example with chalk, following the movements of the light beam on the support. Once the contours of the drawing materialized, the painter or painters can perform the coloring of the decoration to be made, using paints. FIG. 4 shows a support 1000 on which the drawing is to be drawn, a scaffolding 1100, a first projection apparatus 1200, a second projection apparatus 1300, a support 1400 of the second projection apparatus 1300, a steering apparatus 1500 of the projection device illustrated in Figure 4 and a communication medium 1600 between the projection apparatus 1200 and 1300 and the control apparatus 1500. The control apparatus 1500 is, for example, a computer with the necessary programs to put the process described below. The computer in question is, for example, a general purpose computer, for example of PC type (for personal computer or personal computer). It is equipped with a processor, mass memories, RAMs, a keyboard, a mouse, interface connectors with the other elements of the device, remote radio communication means for receiving the signals of the remote control and a screen, these elements are not shown, for the sake of clarity, in FIG.

To provide the initial image to be reproduced on the monumental support, it is possible to implement a scanner or a drawing software, which provides a Bitmap file (in which at each point of the image is associated several values of color intensities principal), contour extraction software that provides a bitmap image and vectorization software, which transforms an image of binary contours into a set of vectors. In another embodiment, vector drawing software can be implemented.

The communication medium 1600 is, preferably, non-wired, for example WIFI, infrared, wireless BLUETOOTH. The support 1000 on which the drawing is to be drawn takes here the shape of a water tower. The projection devices are each adapted to follow, at the point of impact of a narrow light beam on the support 1000, the outlines of a drawing. However, the scaffold 1100 interposes between the support 1000 and each of the projection apparatus 1200 and 1300 and thus intercepts the light beams emitted by the projection apparatus 1200 and 1300. According to the present invention, thanks to the use of two projection apparatus in two positions correctly spaced, or the same device in two different positions, with a modification of the representation of the contours between the two positions so that the contours followed by the light spots on the support 1000 are substantially identical, reduces or eliminates the problem of interception of light beams by obstacles such as scaffolding 1100.

To implement this solution, the control unit 1500 uses geometrical data to calculate the projection deformation corrections due to the positions of the projection devices 1200 and 1300 with respect to the support 1000.

The control device 1500 synchronizes, in the geometric sense, the projection devices 1200 and 1300. It performs, for example, the following steps:

- first step: modeling the support in three dimensions. This modeling can be done from architectural plans, by means of a 3D scanner (existing system used in topography or by any other means, for example, topographical surveys, volume measurement by stereo photography); second step: to know the location in space of at least two laser image reproduction systems. This measurement can be done, for example, by means of GPS coupled with an inclinometer, by means of a distance measurement with a laser range finder possibly associated with an inclinometer (this system requires the use of a target), the range finder can be incorporated in the laser apparatus; third step: positioning the image on the support. This positioning makes it possible to determine a start point of the image plot. This positioning can be done by means of a measurement of the point by GPS or by pointing the laser systems on a point of the support whose position is known;

fourth step: an image to be drawn is calculated according to each position of the projection apparatuses, so that the two apparatuses draw an identical design on the support, but according to different points of view;

fifth step: the recalculated image for each position is sent to each of the respective projection apparatus, via the communication medium 1600, and the control apparatus 1500 simultaneously controls the projection apparatuses, if they are two , or successively the same projection apparatus positioned in two different positions. Then, the image reproduction procedure is as follows: the decorator traces the contours of the decoration to be made, applying a visible trace, for example with chalk or paint, following the pattern provided by the position of the point luminous impact of the light beam on the surface to be decorated. He can then, if necessary, put in color the drawing, by painting the surfaces delimited by the outlines preliminary drawn.

Thus, the decorator traces, for example with chalk, the contour visualized by the displacement of the laser beam on the support. Once all the contours have been followed, the user can color the decoration, using the contours shown by the chalk lines. In a variant, the decorator spreads, on the support 1000, a photosensitive layer at the wavelength of the laser beam, preferably invisible, the displacement of the laser beam on the support locally varying the appearance of this photosensitive layer.

It is observed that this last stage of image reproduction can be replaced by any existing tracing system, laser, range finder or video cameras (see process with camera and multimedia glasses), in this case will be used several video camera simultaneously filming the same support to decorate but at different angles of view, the image to be embedded in the video signal of the camera being the scene to be made. The cameras are capable of transmitting a video image with the overlay to a video image receiving means on which it is displayed and can be viewed by the operator. This receiver means may be multimedia glasses, a video screen and other display device. The geometric characteristics of the image to be embedded are recalculated according to the method of the present invention.

With these provisions, if the field of vision of a camera is hidden by any obstacle, such as for example a scaffolding, a ladder, a hoist and the like, the user can switch from a camera to the other to have an image free from these obstacles.

In a variant, the first four steps are replaced by:

a step of memorizing directions of the light beam corresponding to characteristic points on the support, for example four corners of an area in which the whole of the drawing is to be made or of the four corners and four midpoints of this area; zone, in the case where, as here, the surface on which the drawing is to be reproduced is curved and

a step of deforming the image of the contours to be reproduced so that its characteristic points correspond to the directions memorized during the first step.

It is observed that, in this variant, it is necessary to know the general shape of the area of the support 1000 that will receive the drawing. For example, here the general shape is a vertical cylinder with a circular base.

In another variant, rather than moving the projection apparatus, it implements a mirror allowing it to send, on the support 1000, light rays virtually from a second position. It is observed that additional projection devices can be added to further improve the visibility of the light point on the support and reduce the risk of having points masked by the scaffolding for each of the projection devices.

In the case where a laser range finder without inclinometer is used, the inclination can be determined by trigonometric calculation. In this case one of the lasers is horizontal or the target is horizontal. The calculation of the positioning will include a step of calculating the inclination of the lasers.

The method outlined above can also be applied when drawing a multiple-sided design of a support without a single projection system being sufficient to draw the contours on all relevant faces.

FIG. 5 shows the same elements as in FIG. 4, to which is added a target 2000 on or near the support 1000 and a telemeter 2100, for example by hand, which makes it possible to locate, in space, locations or positions, projection apparatus 1200 and 1300. It is observed that each projection apparatus 1200 and 1300 is provided with an inclinometer 2200 which provides the inclinations in two perpendicular directions.

The inclinometer 2000 gives the inclination of each projection apparatus. This inclination and the measurement of the angle of the light beam with respect to the projection apparatus, for several points characteristic of the target, combined with the distance measured by the range finder 2100, make it possible to determine the position of the projection apparatus, according to known geometric calculations.

FIG. 6 shows the same elements as in FIG. 4, to which is added an inclinometer 3200 associated with each projection apparatus and a positioning system with reference to radio signals 3100. This positioning system 3100 implements satellite signals or terrestrial signals to locate the position in space of each projection apparatus. It is, for example, type GPS (registered trademark for Global Positioning System or satellite positioning system), preferentially differential, DGPS.

The inclination being given by the inclinometer, the configuration of each projection apparatus is fully known. FIG. 7 shows the same elements as in FIG. 6, the projection apparatuses consisting here of cameras 4200 and 4300 and the decorator being equipped with a display screen, here 4400 multimedia glasses equipped with a receiver image and means for displaying an image facing the eyes of the user. The reader will be able to refer to document FR 2 829 899 in order to better understand this particular embodiment of the device that is the subject of the present invention.

It is recalled that document FR 2 829 899 describes a method and a device for reproducing patterns on supports, in particular of large sizes and of various shapes, such as, for example, facades, monuments, or natural sites. According to the method, - a specific point of view of the medium is selected, - the image of said specific point of view is framed with the aid of a video camera, the image is sent to a display screen,

- one incrust, with a computer, on the image of said point of view, the pattern to reproduce,

the resulting incrustation is transmitted to the display screen,

positioning at the level of the support, in the field of vision of the camera, reproducing the pattern on said support, using a tracing tool, following the contours of the pattern embedded in said image, such as that it appears simultaneously on the display screen.

Preferably, the tracing tool, for example a pistol, comprises means enabling it to emit a signal, light and / or sound, of variable intensity, when the user points it on the contours of said pattern to be reproduced and / or means capable of causing its automatic triggering when it is pointed exactly on the contours of said pattern to be reproduced.

The operator begins by selecting the optimum point of view of the medium on which he is responsible for painting. He then positions at this location an apparatus allowing him to frame this point of view in three dimensions, and to return an image to him to a visualization screen, when he will be himself in place, on the scaffolding or the crane. , at the level of the support. The framing of said point of view makes it possible, by means of the pixels of the apparatus employed, for example a camera, to define a grid of abscissae and ordinates, more or less fine and precise.

Once the point of view is framed, and the image of the point of view captured and sent to the screen, the operator performs, on said image, an overlay of the pattern to be reproduced, the latter having been previously digitized. The operator then positions himself at the level of the support, if possible so as to be in the field of view of the framing apparatus, and to appear himself in the image he is viewing. He thus sees appear on the display screen, both the support, the pattern embedded in the support, and his own person. In order to reproduce the pattern, it then suffices to follow the contours of the latter, as they appear on said display screen, and to the extent that they appear in a sufficiently precise manner, using a suitable tool , such as, for example, a brush, or an aerosol.

Said data relating to the framed image are transmitted to a display screen, preferably lightweight and portable, such as, for example, audio / video glasses of the type used in the field of multimedia, worn constantly by the operator when executing the pattern on the media.

FIG. 8 shows that, in a particular mode of implementation of the method that is the subject of the present invention, it first comprises a step 5000 for modeling the support in three dimensions. For example, during step 5000 of modeling of the support in three dimensions, it implements a narrow light beam whose position is controlled to match the characteristic points identified on the support (see Figure 9). According to another example, during step 5000 of support modeling in three dimensions, it implements architectural plans of the support. In another example, at During the step of modeling the medium in three dimensions, a 3D scanner is used.

Then, for at least two locations of projection apparatuses, a step 5100 of calculation of an image to be drawn is carried out according to the model of the medium determined during step 5000. In particular embodiments, each step of calculating an image comprises a step 5150 of determining the position of at least two locations of projection apparatuses. For example, during the step 5150 of position determination of at least two locations of projection apparatus, implementation of positioning equipment refers to radio signals. According to another example, during step 5150 for determining the position of at least two locations of projection apparatus, an inclinometer is used. According to a third example, during step 5150 of position determination of at least two locations of projection apparatus, a range finder is used.

Each step 5100 for calculating an image also comprises a step 5200 of locating a point on the support.

Then a tracking step 5300 is carried out, on the support to be decorated, from each location, with at least one projection apparatus, of at least a portion of the contours of the calculated image corresponding to said location.

During the tracking step 5300, the contour is followed with a narrow light beam, preferably a laser beam, projected onto the support to be decorated from each location.

In embodiments, during the monitoring step 5300, contours are simultaneously monitored with at least two projection devices positioned in at least two of said locations, the projection apparatuses following an identical path on the support. , from different location. In these embodiments, preferentially, during the tracking step 5300, the projection apparatuses are synchronized so that they follow, at each instant, the same contour part.

In other embodiments, during the tracking step, contour tracking is successively carried out with a projection apparatus positioned successively at said locations.

Preferably, the step 5300 of tracking comprises a step 5350 remote control contour tracking by the decorator, which can thus take longer to draw a complex outline, stop the path or go back, for example.

As seen in FIG. 9, a cylindrical support with a circular base, such as the water tower illustrated in FIG. 4, observed by a projection apparatus positioned as the projection apparatus 1200, has an apparent deformation which corresponds verticals at converging lines at the vanishing point and horizontal at arcs of ellipses.

From eight points 6010 to 6080, placed at the vertices and at the center of the sides of a rectangle with a horizontal base on the support 1000, and for which the positions of the stepping motors of the projection apparatus are indicated, it is possible to determine the reciprocal deformation for projecting a rectangular image so that it appears without deformation in juxtaposition on the rectangular zone drawn on the support 1000.

For this purpose, known geometric characteristics are used. For example, the vanishing point is determined. Then, from the knowledge that we have on the ellipses (for example, for each ellipse, the small axis passes through the vanishing point and the major axis is perpendicular to the minor axis), and with the coordinates of the points 6010 to 6080, the equations of the ellipses are determined.

It is observed that this empirical determination of the deformation to be compensated, since it implements no knowledge of the positioning of the projection apparatus or the support, but only the general shape of the support, here circular cylindrical can also apply calculating the deformation to be applied to the initial image as a function of the point of view where it is desired to appear without deformation as the deformation to be applied to draw the contours from other positions of the projection apparatus or devices.

As seen in FIG. 3, the projection apparatus allowing the narrow light beam, preferably a laser beam, to be displaced on the support to be decorated, comprises a frame 305 on which a laser diode 190 projecting a light ray is fixedly mounted. 315 to a mirror 180 with a controlled and controlled orientation mounted on a mount 325 having two geometric pivot axes perpendicular to each other, in which the mirror 180 is pivoted to be oriented and reflect the narrow light beam towards the wall support in a position depending on the position of the mirror 180.

One of the pivot axes that has the mount 325 is vertical.

This mount 325 comprises a U-shaped element comprising two horizontal branches 335 and a lateral branch 340. At each horizontal branch 335 is fixed a vertical pin 345. Each vertical pin 345 is engaged in rotation in a fixed bearing and one of the two pins is coupled, beyond the bearing, to the output shaft of a step motor 170 fixed by its frame to the frame 305 of the projection apparatus.

The mirror 180 is mounted for fixing on a horizontal shaft 360 rotatably mounted in a bearing mounted on the lateral branch 340. The horizontal shaft 360 is coupled to the output shaft of a step motor 170 fixed by its carcass to the U-shaped element. Each motor 170 and 175 preferably comprises an encoder for controlling the orientation of the mirror 180, so that the computer 100 can control the movement of these motors. Alternatively, a stop sensor resets the position of the stepper motors.

The point of impact 330 of the light beam 315 on the mirror 180 is preferably situated at the intersection of the two pivoting geometric axes, this intersection point being located in the center of the reflecting surface of the mirror 180.

It is observed that, in particular embodiments, the mirror is replaced by the laser, the latter then being mobile, for example mounted directly in the mount 325, which makes it possible to halve the angle traveled for each step of each of the stepper motors and therefore to double, in each direction, the positioning accuracy of the point of impact of the light beam on the support. Preferably, in this particular case, the direction of the light beam emitted by the laser and the geometric axes of rotation of the output shafts of the stepper motors intersect at a single point. In the case where the projection apparatus is associated with a GPS or a range finder, knowledge of the value of the distance separating it from the support allows the laser to be off-center with respect to the axes of rotation of the output shafts of the motors. step by step, the deformation resulting from this decentering can easily be calculated and corrected. The positioning of the laser will take this correction into account.

The projection apparatus 1200 and 1300 are in accordance with the projection apparatus previously described. They each comprise a stepper motor control software, two stepper motors, a mirror and a laser diode oriented towards the mirror. This electro-optical system makes it possible to project a laser beam at any point of the support that is not masked by an obstacle, the point in question corresponding to the positions of the stepping motors that put the mirror in motion around two axes of rotation. A remote control (not shown) remotely controls the operation of the stepper motors in manual mode. It should be noted that the projection apparatuses are controlled simultaneously from a suitable control computer.

The software and more particularly the software 120, 130, 135, 140 and 150 can be integrated in the control computer, the software 160 is usually integrated in an element associated with the stepper motor. In another less convenient case because requires a lot of wiring, the software

160 can also be integrated into the control computer.

In another case the control computer is integrated with one of the lasers, the latter then enslaving the other lasers.

Claims

1 - Process for producing monumental decorations, characterized in that it comprises:

a step of defining outlines (205 to 225) of an image representing the decoration to be produced and a tracking step, with a narrow light beam projected on the support to be decorated, of at least a part of said outlines (255 at 300).

2 - Process according to claim 1, characterized in that, during the tracking step (255 to 300), the light beam consists of a laser beam.

3 - Process according to any one of claims 1 or 2, characterized in that the tracking step comprises a remote control step (265, 275, 285, 295) of the displacement of the source of the light beam.

4 - Process according to claim 3, characterized in that the remote control step comprises a step of controlling the tracking speed of the portion of the contour followed (265, 275).

5 - Process according to any one of claims 1 to 4, characterized in that it comprises a step of digitizing (205) a representation of the decoration to be produced by image scanner.

6 - Process according to any one of claims 1 to 5, characterized in that it comprises an image processing step with contour extraction in a digital representation of the decoration to be produced (220). 7 - Method according to any one of claims 1 to 6, characterized in that it comprises a step of determining positions of reference points on the support (240, 245) and an anamorphosis correction step (250) .

8 - Process according to any one of claims 1 to 7, characterized in that it comprises a step of determining the radius of curvature of the outline to be drawn and, during the tracking step (260 to 300), the speed of displacement of the light beam on the support is a function of said radius of curvature.

9 - Process for producing monumental decorations on a support (1000), according to claim 1, characterized in that it comprises:

a step (5000) of modeling the support in three dimensions; for at least two locations of projection apparatus, a step of calculating (5100) an image to be drawn according to the model of the support and

a tracking step (5300), on the support to be decorated, from each location, with at least one projection apparatus, of at least a portion of the outlines of the calculated image corresponding to said location. 10 - Process according to claim 9, characterized in that each step of computing (5100) an image comprises:

a step (5150) of determining the position of at least two locations of projection apparatus and

a step (5200) of locating a point on the support. 11 - Process according to claim 10, characterized in that, during the step (5150) of position determination of at least two locations of projection apparatus, implementing a positioning equipment referring to radio signals.

12 - Process according to any one of claims 10 or 11, characterized in that, during the step (5150) of position determination of at least two projection apparatus, an inclinometer is used.

13 - Process according to any one of claims 10 to 12, characterized in that, during the step (5150) of position determination of at least two locations of projection apparatus, a range finder is used. . 14 - Process according to any one of claims 9 to 13, characterized in that, during the step (5000) of modeling the support in three dimensions, it implements a narrow light beam which is controlled position for match it with characteristic points marked on the support.

15 - Method according to any one of claims 9 to 14, characterized in that, during the step (5300) of tracking, the contour is followed with a narrow light beam projected on the support to be decorated from each location.

16 - The method of claim 15, characterized in that, during the step (5300) tracking, the light beam consists of a laser beam.

17 - Process according to any one of claims 9 to 16, characterized in that, during the step (5300) monitoring, is simultaneously carried out contour monitoring with at least two projection devices positioned in at least two so-called locations, the projection apparatuses following an identical path on the support, from different locations.

18 - Process according to claim 17, characterized in that, during the step (5300) tracking, the projection apparatus is synchronized so that they follow, at each moment, the same portion of contour.

19 - Process according to any one of claims 9 to 18, characterized in that, during the step (5300) of monitoring, is successively carried out contour monitoring with a projection apparatus positioned successively said locations.

20 - Process according to any one of claims 9 to 19, characterized in that, during the step (5000) of modeling the support in three dimensions, it implements the support planes.

21 - Process according to any one of claims 9 to 20, characterized in that, during the step (5000) of support modeling in three dimensions, it implements a 3D scanner. 22 - Method according to any one of claims 9 to 21, characterized in that the step (5300) tracking comprises a step (5350) remote control contour tracking. 23 - Method according to any one of claims 9 to 22, characterized in that the step (5300) of monitoring comprises a step of implementing at least one camera (4200, 4300) and a means viewing (4400) an image facing the eyes of the user. 24 - Device for producing monumental decorations, characterized in that it comprises:

a means for defining contours of an image representing the decoration to be made (100, 110, 130) and a projection means (100, 160 to 190) for a narrow light beam (315) on the support to be decorated. (50), and moving the position of said light beam to track at least a portion of said contours with said light beam.

25 - Device according to claim 24, characterized in that the projection means comprises a source of a laser beam (190). 26 - Device according to any one of claims 24 or 25, characterized in that it comprises a remote control.

27 - Device according to claim 26, characterized in that said remote control is adapted to control the tracking speed of the part of the contour followed.

28 - Device according to any one of claims 24 to 27, characterized in that it comprises an image scanner (110).

29 - Device according to any one of claims 24 to 28, characterized in that it comprises an image processing means (100, 130) adapted to extract contours in a digital representation of the decoration to be produced.

30 - Device according to any one of claims 24 to 29, characterized in that it comprises means for determining positions (100, 160 to 190) of reference points on the support and anamorphosis correction means.

31 - Device according to any one of claims 24 to 30, characterized in that it comprises means for determining the radius of curvature (100, 135) of the contour to be traced and the means of displacement of the light beam on the support is adapted to move the light beam on the support according to said radius of curvature.

32 - Device according to any one of claims 24 to 31, characterized in that the displacement means comprises at least one stepper motor (170, 175).

33 - Device for producing monumental decorations on a support (1000), characterized in that it comprises: - a means of modeling the support in three dimensions;

a means for calculating, for at least two locations, an image to be drawn according to the model of the support and

- At least one projection apparatus (1200, 1300, 4200, 4300) adapted to follow, on the support to be decorated, from each location, at least a portion of the contours of the calculated image corresponding to said location.