Method and system for simulating spray-painting operations in virtual reality, augmented reality or mixed reality environments

Abstract

The present invention mainly relates to a method for simulating spray-painting operations that is suitable for computing paint projection surfaces (12) on a simulated workpiece (1), based on the position and orientation of a physical workpiece (T) and a physical tool (2'); and for determining the shape and volume of a paint coating (4) based on input paint parameters. Said shape and said volume are calculated as functions of depositing painting material on one or more accumulation regions (13) of the paint projection surfaces (12) which, for the applied layers (3) as a whole, form the paint coating (4). The invention further relates to a simulation system comprising means that are configured to implement the described method and to a corresponding computer program.

Description

[0001] DESCRIPTION

[0002] METHOD AND SYSTEM FOR SIMULATING SPRAY PAINTING OPERATIONS IN VIRTUAL REALITY, AUGMENTED REALITY, OR MIXED REALITY ENVIRONMENTS

[0003] FIELD OF INVENTION

[0004] The present invention relates, in general, to the field of learning through augmented reality techniques and, more specifically, to methods and systems for simulating painting operations by computer, for example for the simulation of spray painting techniques, application of a flow of abrasive materials on a surface, protective surface treatments or, in general, the dispersion by pressure of fluid materials on surfaces of any type, preferably through augmented reality methods. Within the scope of the present invention, the term "augmented reality" will also be understood to refer to any other visual representation techniques using virtual reality or mixed reality.Likewise, although the present invention generally refers to paint as the preferred dispersion and / or spraying material, within the scope of the invention, this term shall be understood to mean any particulate, fluid and / or viscous material that can be dispersed or sprayed onto a surface by pressure, forming a coating and / or permanently or temporarily modifying the nature of said surface. Examples of applications for this type of material include, for example, liquids, resins, foams, varnishes, or particulate materials such as silica, glass, metals, or plastics. Finally, within the scope of the invention, the term "spraying" shall be understood to mean any technique for projecting, dispersing, or propelling said materials by pressure.

[0005] BACKGROUND OF THE INVENTION

[0006] Known systems and methods for simulating spray-on painting operations require intensive use of graphics processing resources to perform the simulations. Thus, in conventional paint simulation systems, the calculations and rendering of the simulated paint coating (i.e., the accumulation of paint material deposited at the interface of painted surfaces) require considerable computational power. This effectively limits the performance of the equipment on which such simulation can be implemented, which is generally limited to computers with dedicated graphics processing units. For example, mobile devices and / or web browsers typically do not allow the implementation of conventional paint simulation techniques.Furthermore, such conventional systems and methods are technically cumbersome to implement, and present difficulties for the development of new features and functionalities, such as the implementation of complex painting patterns and / or simulation of different materials or specific painting techniques, such as low-pressure spray painting or airless spray painting.

[0007] In current paint simulation techniques, the amount of paint material transferred from the painting tool used (e.g., a compressed air spray gun) to the paint coating on the workpiece cannot be modeled with great accuracy due to the aforementioned computational limitations. However, accurate modeling of the paint coating is crucial in this field to realistically simulate the successive layers of deposited material required during each painting operation.

[0008] With the aim of improving conventional paint simulation techniques, various solutions have been developed in recent years that allow for a partial reduction in the computational requirements of simulation operations while maintaining realistic and even photorealistic visualization results, obtaining simulation images comparable to those of real painting. An example of these techniques is described in patent application US 2013 / 0323695 A1 and patent US 10,909,876 B2. These documents describe different methods for simulating a paint coating by rendering a plurality of particles or droplets, the accumulation of which forms a layer of paint over a projection area.While this type of technology allows for satisfactory simulation results in terms of realism for simple painting operations, its implementation is still too demanding in terms of computational resources for more complex cases. This severely limits the scalability of this equipment in practice. As a result of the recent improvements in painting operation simulation techniques, it would be desirable to develop realistic calculation procedures for paint coating properties that can be simulated for different types of tools (spray guns, robotic arms, etc.) and that offer improved performance compared to known techniques.Having these indicators is extremely valuable in the field of painting skills training and learning technologies, as they allow learners, as well as their instructors, to obtain precise quantitative information about the quality of a given painting operation. In the field of robotic painting, this capability would allow for the refinement of painting robot learning procedures.

[0009] It is important to clarify that, to date, there are no mature techniques for adequately calculating simulated paint coating formation patterns based on dynamic paint parameters (fan opening, air / paint flow, pressure, etc.), which are also computationally demanding. Thus, the only realistic alternative to this possibility, which currently relies largely on particle rendering, is to conduct real paint tests. This requires the consumption of significant material resources, primarily in the form of parts and paint material, with the resulting environmental impact. It also poses a greater risk of accidents for less experienced users, necessarily imposing a greater need for human supervision.

[0010] In this context, obtaining the aforementioned simulation procedures with realistic and scalable properties would also be very valuable for simulating a wide variety of paint tests using advanced techniques. Again, obtaining realistic information about these properties through simulation, without the need to render individual particles or droplets, would represent significant savings in resources (both computational, material, and energy consumption), with a corresponding improvement in performance, and with significant benefits in safety and environmental impact.

[0011] Furthermore, having simulation calculation techniques for realistic properties of advanced paint pattern formation can also be highly beneficial in real-world painting operations. Thus, realistic simulation of the properties of a simulated paint coating, based on the characteristics of a real coating, can advantageously replace traditional techniques, which are expensive and require high specialization.

[0012] The present invention is aimed at solving the above problems and limitations, by means of a novel method of simulating spray painting operations, together with a computer program and a system that implements said method.

[0013] BRIEF DESCRIPTION OF THE INVENTION

[0014] The method and system of the invention preferably have as their object the simulation of painting operations, preferably the simulation of spray painting techniques, or of surface treatment techniques for spray protection (in which a paint material or any other coating material is deposited on the surface of an object), as represented and described, respectively, in relation to the description, figures and claims of this document.

[0015] More specifically, a first object of the invention relates, in general, to a method and a system adapted to provide a simulation environment through augmented reality, comprising hardware / software means adapted to support the calculation, rendering and visualization of preferably three-dimensional (3D) graphics, as well as means of communication between users of simulation software, together with an implementation of mathematical methods and / or algorithms that simulate 3D painting processes.

[0016] The method and system of the invention are implemented, in a preferred embodiment thereof, by means of software that can be used, for example, to manage a virtual classroom for learning painting techniques, and an augmented reality application that simulates a painting process in a real environment. Thus, by using augmented reality techniques, virtual images corresponding to painting operations, generated by computer, are superimposed or transposed onto real environments to define and / or create an augmented, virtual, or mixed reality that provides users with a tool to learn different painting techniques. In some examples of the invention, the user (for example, a painter or an apprentice) uses a screen, video glasses, and / or any other display device adapted for the purpose.The display or glasses can, in turn, be integrated into a commercial paint mask and present mixed reality to a user wearing the paint mask. This provides a realistic simulation of real-life painting conditions.

[0017] Although the present invention typically refers to operations performed by a user, said user will be understood, in a generic way, not only as a human user, but as any robotic element that performs or tests painting operations.

[0018] The embodiments of the systems and methods described as examples of the invention preferably provide a simulated visual representation of painting workpieces. However, said workpieces will be understood, within the scope of the invention, as any elements, real or simulated, that comprise the regions on which the paint is deposited. Thus, for example, a workpiece can be understood as an industrial part, a vehicle, a construction element, or an engineering element, real or simulated, on which the painting operation is to be performed.

[0019] For their part, the paint coatings obtained with the method and simulation system of the invention realistically represent the typically superficial depositions of paint material, in one or several layers, depending on the type of painting operation performed. In different embodiments of the invention, said method and system can be used to realistically reproduce the generation of defects in the paint coating, such that a user can visualize them and better understand how and why they occurred, learning how to avoid them in successive operations. In other embodiments, the systems and methods of the invention can distinguish between different techniques used to form a paint coating and realistically represent it in different formats in the visualization medium chosen to represent the simulation.

[0020] In relation to conventional simulations of painting operations, the systems and methods described by the invention make it possible to correctly calculate the amount of material transferred from a painting tool to a workpiece, adjusting the geometry of the coating to improve the accuracy of the interaction between different layers, improving the representation of the paint coating formed. Compared to known methods and systems, the invention also makes it possible to realistically calculate the paint accumulation regions on the surface of the workpiece, depending on the compressed air flow used, and / or the paint itself sprayed from the simulated painting tool. These accumulation regions can be shown to the user in detail throughout the coating formation stages, for each successive layer of deposited paint material.This improved capability cannot be achieved in real painting operations because, in these operations, the paint coating is formed non-reversibly, as successive layers of material are deposited on top of each other.

[0021] More specifically, a first object of the invention relates to a method for simulating a spray painting operation, wherein said painting operation represents the application of one or more layers of paint material onto a physical workpiece, and where said layers of paint material configure a paint coating; wherein said method comprises the operation of:

[0022] - a physical tool operable by a user;

[0023] - at least one position detector, adapted to receive information corresponding to the position and orientation of the physical workpiece and / or the physical tool; and

[0024] - a simulation device communicatively connected to the physical tool and the position detector, said connection being understood as any means that allows the exchange of information between said elements, or a subset thereof, and which may be carried out using a physical medium or be wireless; where said simulation device is adapted with hardware and software means comprising a paint parameter configurator, a paint spray calculator, a renderer and a display, where said method comprises performing the following steps:

[0025] - obtain, with the position detector, information corresponding to the spatial location of the physical workpiece and the physical tool, and send said spatial location information to the simulation equipment;

[0026] - calculating, using the position detector and / or simulation equipment, the position and orientation of the physical workpiece and the physical tool, from the information obtained by the position detector; - establishing, using the paint parameter configurator, one or more input parameters characterizing a painting operation for one or more layers of paint material, said input parameters comprising at least one of the following: composition of the deposited paint material, type of painting process, paint and / or air output flow rate, deposited paint output fan opening;

[0027] - rendering, with the renderer, at least one simulation domain in which a simulated workpiece and a simulated painting tool representing, respectively, the physical workpiece and the physical tool are represented within a three-dimensional painting space.

[0028] Advantageously, the method of the invention additionally comprises the following steps, executed in their entirety or as a selection thereof, in any combination or order technically possible:

[0029] - calculating, with the paint spray calculator, a paint projection surface on the simulated workpiece, from the position and orientation of the physical workpiece and the physical tool, as well as from the input parameters, for each layer, where said paint projection surface is also configured as one or more paint accumulation regions, where said accumulation regions are determined, with the paint spray calculator, depending on the paint and / or air output flow established with the paint parameter configurator;

[0030] - solving, with the paint spray calculator, the shape and volume of the paint coating from the input paint parameters, where said shape and said volume are calculated as functions of deposition of paint material on the one or more accumulation regions of the paint projection surface that, together for the applied layers, configure the paint coating;

[0031] - render, with the renderer, the paint coating in the simulation domain;

[0032] - represent, with the visualized^ the simulated workpiece, the simulated painting tool and the rendered paint coating.

[0033] In a preferred embodiment of the method of the invention, in the step of solving, with the paint spray calculator, the shape and volume of the paint coating from the input parameters, the paint material deposition functions are globally or locally decreasing functions from the centers of the paint accumulation regions.

[0034] In another preferred embodiment of the invention, the step of solving, with the paint spray calculator, the shape and volume of the paint coating from the input parameters, for each of the layers of paint material, comprises generating one or more paint dispersion patterns.

[0035] In another preferred embodiment of the invention, the step of solving, with the paint spray calculator, the shape and volume of the paint coating, from the input parameters for each of the layers of paint material, comprises the generation of one or more roughness, dripping and / or displacement patterns of paint deposited on the simulated workpiece.

[0036] In another preferred embodiment of the invention, the step of solving, with the paint spray calculator, the shape and volume of the paint coating, from the input parameters for each of the layers of paint material, comprises calculating one or more indicators relating to the properties of the paint deposited on the simulated workpiece, said indicators also comprising one or more of the following: time used during the painting operation, efficiency of the transfer of deposited material, consumption of paint material, presence of defects.

[0037] In another preferred embodiment of the invention, the step of calculating, with the paint spray calculator, a paint projection surface on the simulated workpiece, from the position and orientation of the physical workpiece and the physical tool, comprises a correction of the shape and / or the position of said projection surface by the effect of gravity, by the effect of turbulence, by the effect of resistance or drag of air molecules, by the effect of temperature and / or ambient humidity, and / or by acceleration due to an air flow in one or more directions of three-dimensional space.

[0038] In another preferred embodiment of the invention, the step of calculating, using the paint spray calculator, a paint projection area on the simulated workpiece, based on the position and orientation of the physical workpiece and the physical tool, comprises one or more corrections determined based on the shape of the simulated workpiece. More preferably, the corrections determined based on the shape of the simulated workpiece comprise determining one or more occlusion regions in the simulated workpiece.

[0039] In another preferred embodiment of the invention, the step of calculating, with the paint spray calculator, a paint projection surface on the simulated workpiece, from the position and orientation of the physical workpiece and the physical tool, comprises determining one or more occlusion regions in the simulated workpiece due to the existence of one or more virtual objects arranged between the simulated workpiece and the simulated painting tool and / or due to the presence of occlusive elements existing in the workpiece itself.

[0040] In another preferred embodiment of the invention, the simulation method further comprises performing, with the parameterizer, a step of parameterizing one or more surfaces of the simulated workpiece, where said parameterization comprises mapping a data matrix along said surfaces of the simulated workpiece, and where said data matrix comprises a plurality of information cells, where each information cell comprises one or more values ​​indicative of one or more geometric properties of the simulated workpiece, of an amount or a thickness of simulated paint deposited on a region of the simulated workpiece, of a fluidity of the paint deposited in a region of the simulated workpiece, and / or of a direction, sense and / or module of a velocity vector associated with a displacement of the paint deposited on the surface of the simulated workpiece.More preferably, the mapping of the data matrix along the surfaces of the simulated workpiece is a mapping such that each parameterization point or region of the surfaces of the simulated workpiece corresponds to a single information cell of the data matrix.

[0041] Even more preferably, the parameterization comprises mapping a plurality of data matrices, and / or an n-dimensional data matrix along the surfaces of the simulated workpiece, where the information in the information cells of said matrices has a different resolution between at least two of the data matrices, and / or between at least two dimensions of one or more of the data matrices. In another preferred embodiment of the invention, the simulation method additionally comprises carrying out, with the paint spray calculator, a step of verifying the conservation of the mass of the simulated paint generated by the simulated painting tool, in relation to the simulated paint deposited on the simulated workpiece.More preferably, the step of calculating, with the paint spray calculator, a paint projection area on the simulated workpiece, comprises determining one or more paint loss zones where the mass conservation check is not met.

[0042] In another preferred embodiment of the invention, the step of solving, with the paint spray calculator, the shape and volume of the paint coating from the input parameters for each of the layers of paint material comprises determining a value, a property or a probability of transfer of the deposited paint onto the simulated workpiece. More preferably, the value, property or probability of transfer of the paint is determined as a function of an angle of incidence of the simulated paint on the simulated workpiece, a distance between the simulated painting tool and the simulated workpiece, and / or an impact velocity of the simulated paint on the simulated workpiece.

[0043] In another preferred embodiment of the invention, the step of solving, with the paint spray calculator, the shape and volume of the paint coating from the input parameters for each of the layers of paint material comprises generating one or more drying patterns of paint deposited on the simulated workpiece.

[0044] In another preferred embodiment of the invention, one or more of the input parameters comprise the type of painting process, and wherein said type of painting process comprises:

[0045] - painting by spraying with compressed air;

[0046] - painting by spraying with low-pressure compressed air;

[0047] - painting by airless spraying.

[0048] A second object of the invention relates to a computer program adapted to implement, in a simulation system, a method according to any of the embodiments described herein. A third object of the invention relates to a system for simulating a spray painting operation, where said painting operation represents the application of one or more layers of paint material onto a physical workpiece, and where said layers of paint material configure a paint coating; where said system comprises:

[0049] - a physical tool operable by a user;

[0050] - at least one position detector, adapted to receive information corresponding to the position and orientation of the physical workpiece and the physical tool; and

[0051] - simulation equipment connected to the physical tool and the position detector; said simulation equipment is equipped with hardware and software means comprising a parameterizer, a paint spray calculator, a renderer, and a display, where, advantageously, the hardware and / or software means of the simulation equipment are adapted to perform the steps of a method according to any of the embodiments described herein.

[0052] In a preferred embodiment of the system of the invention, the physical tool comprises:

[0053] - a real painting tool, and / or

[0054] - a training painting tool.

[0055] In another preferred embodiment of the system of the invention, the physical tool comprises a robotic arm.

[0056] In another preferred embodiment of the invention, the system comprises:

[0057] - at least one position indicator of a physical workpiece and / or of the physical tool and, additionally,

[0058] - and where the position detector is adapted to receive information corresponding to the position of the workpiece and / or the physical tool via the position indicator. In another preferred embodiment of the system of the invention, the position indicator comprises one or more of the following: optical markers, printed markers, and / or natural markers.

[0059] In another preferred embodiment of the system of the invention, the position detector comprises one or more of the following: cameras, depth cameras, inertial sensors, haptic sensors, thermal sensors, mechanical sensors, electromagnetic sensors, laser sensors.

[0060] DESCRIPTION OF THE DRAWINGS

[0061] The features, aspects and advantages of the present invention will be understood in greater detail from the detailed description that follows, with reference to the accompanying drawings in which like characters represent like parts throughout the figures, in which:

[0062] Figure 1 shows a perspective view of the main elements simulated with the method of the invention, in a preferred embodiment thereof, where a simulated paint coating formed by three simulated layers of material is shown (differentiated in the figure by three filling patterns), where said simulated paint coating is deposited on a simulated work piece, by means of a simulated painting tool which, for said embodiment, represents a compressed air paint gun.

[0063] Figure 2 schematically represents the main elements of the simulation equipment of the invention, in a preferred embodiment thereof.

[0064] Figure 3 shows a physical workpiece and a physical tool according to a preferred embodiment of the invention, wherein the physical workpiece and said physical tool comprise position indicators that can be detected by the position detector.

[0065] Figure 4 shows a perspective view of the paint coating obtained from the method of the invention, where a projection surface is determined as the intersection between the simulated paint emission cone or fan and the surface of the simulated workpiece. Figure 5 illustrates, by way of example, the formation of paint accumulation regions on the paint projection surface on the simulated workpiece, according to a preferred embodiment of the invention.

[0066] Figure 6 illustrates a preferred embodiment of the invention, where a paint coating is shown comprising a roughness and drip pattern of paint deposited on the simulated workpiece.

[0067] Figure 7 illustrates a preferred embodiment of the invention, in which an example of correction of the shape and / or position of the paint projection surface by the effect of gravity in three-dimensional space is shown.

[0068] Figure 8 illustrates a preferred embodiment of the invention, where an example of correction of the shape and / or position of the paint projection surface is shown, and where said correction comprises the determination of one or more occlusion regions in the simulated workpiece.

[0069] Figure 9 illustrates a preferred embodiment of the invention, where an example of correction of the shape and / or position of the paint projection surface is shown, and comprising determining one or more occlusion regions in the simulated workpiece, due to the existence of one or more virtual objects arranged between the simulated workpiece and the simulated painting tool, or belonging to the simulated workpiece itself.

[0070] Figures 10a-10b illustrate a preferred embodiment of the invention, wherein the surface of the simulated workpiece is parameterized by mapping a data matrix (Fig. 10a), and wherein said data matrix comprises a plurality of information cells. Furthermore, each information cell comprises one or more values ​​indicative of one or more geometric properties of the simulated workpiece, of an amount or a thickness of simulated paint deposited on a region of the simulated workpiece, of a fluidity of the paint deposited on a region of the simulated workpiece, and / or of a direction, sense and / or module of a velocity vector associated with a displacement of the paint deposited on the surface of the simulated workpiece (Fig. 10b).Figures 11-12 illustrate a preferred embodiment of the invention, where the simulated workpiece surface is parameterized by mapping a data matrix of triangular shaped cells (Fig. 11), and where said data matrix is ​​shown with three different simulated paint particle aggregation densities (Figs. 12a-12c), corresponding respectively to a density of 20 particles, 100 particles and 1000 particles per cell.

[0071] Numerical references used in the

[0072] (1) Simulated workpiece

[0073] (T) Physical workpiece

[0074] (2) Simulated painting tool

[0075] (2') Physical tool

[0076] (3) Simulated layers of paint material

[0077] (4) Simulated paint coating

[0078] (5) Simulation equipment

[0079] (6) Paint parameter configurator

[0080] (7) Paint Spray Calculator

[0081] (8) Renderer

[0082] (9) Viewer

[0083] (10) Position detector

[0084] (11) Position indicators

[0085] (12) Paint projection surface

[0086] (13) Paint accumulation region

[0087] (14) Occlusion region

[0088] (15) Virtual object

[0089] (16) Data matrix

[0090] (17) Data matrix information cell

[0091] (18) Paint particles generated in the cell

[0092] DETAILED DESCRIPTION OF THE INVENTION

[0093] Figures 1-10 of this document describe a series of preferred embodiments of the invention, which are incorporated for illustrative purposes and, therefore, do not limit the scope of protection of the claims. As described in the previous sections, a first object of the invention relates to a method for simulating a painting operation, where said simulation is preferably carried out in an augmented reality, virtual reality, or mixed reality environment.In this environment, as shown in Figure 1 , the simulated painting operation preferably represents the application of a simulated paint material onto a simulated workpiece (1), where said application of material is carried out by means of a simulated painting tool (2) (said tool (2) being able to be, for example, a simulated compressed air spray gun, both low and high pressure, a simulated airless spray gun, a simulated painting robotic arm, etc.). Under this representation, the simulated paint material is deposited as one or more layers (3) (understood as substantially superficial extensions of simulated paint material, which can be arranged on top of each other, in total or partial overlap between them as they are generated on the piece (1)), and where the set formed by said simulated layers (3) configures a simulated paint coating (4).The simulated layers (3) therefore represent the passes of material that typically make up the real paint coatings on the real parts.

[0094] Depending on whether the application of the invention relates to virtual, augmented or mixed reality, certain elements simulated by the described method (for example, the simulated workpiece (1), the simulated painting tool (2), etc.) can be generated in relation to corresponding real elements, such as a physical workpiece (T) or a physical tool (2'), the latter being, in different embodiments, a real painting tool (i.e., adapted for the deposition of real paint material) or a training tool (whose dimensions, weight or other properties are similar to those of a real painting tool, but without the ability to deposit real paint material). The physical tool (2') can be operated by a human, robotic or computerized user, either directly or indirectly, from a corresponding interface or control means.

[0095] Thus, by way of non-limiting example, in an augmented reality environment, the method of the invention may comprise the representation of a simulated workpiece (1) and a simulated painting tool (2) on a physical workpiece (T) and a physical tool (2'), respectively (said physical elements are represented in Figure 2 herein). As previously mentioned, in different embodiments of the invention, a physical workpiece (T) may be understood as an industrial part, a vehicle, a construction element, an engineering element, or a part thereof, on which the painting operation and / or its corresponding simulation is to be performed.

[0096] In a preferred embodiment of the invention, as illustrated in Figure 2, the method of the invention comprises the operation of a simulation equipment (5), where said simulation equipment (5) is adapted with hardware and software means comprising a painting parameter configurator (6), a paint spraying calculator (7), a renderer (8) and a display (9). The hardware and / or software means comprising the parameterization configurator (6), the paint spraying calculator (7), the renderer (8) or the display (9) are preferably implementable as milking routines or algorithms or, in general, any computing means. Although, in a preferred embodiment of the invention, said simulation equipment (5) can be used connected to a physical tool (2'), in other embodiments it can be used independently of said tool (2').However, in general the simulation equipment (5) will be adapted to receive information obtained from the operation of said physical tool (2'), for example from its interaction with a human, robotic or computerized user, and / or with a physical workpiece (T), which generates data related to the simulated painting operation that can be parameterized by the configurator (6). In different embodiments of the invention, the connection between the simulation equipment (5) and the physical tool (2') can occur by means of a material connection (for example, through a cable and / or information port) or wirelessly, and both directly and through intermediary elements, adapted for the exchange of said data between the simulation equipment (5) and the physical tool (2'), or to provide information from one to the other.

[0097] Typically, the simulation equipment (5) may comprise any type of computer or a mobile device (e.g., a mobile phone, a tablet, etc.). For its part, as mentioned, the painting parameter configurator (6) is adapted to receive and process information relating to one or more of the following parameters relating to the paint material or type: composition of deposited paint, type of painting process, paint and / or air outlet flow, paint outlet fan opening. In this way, the simulations of the painting operations are mainly based on the input information received by the simulation equipment (5) on the properties of the paint material or the type of painting technique simulated, according to the mentioned parameters.Likewise, in different embodiments of the invention, the input information can be generated artificially (for example, through simulation parameterizations, neural networks, artificial intelligence tools) or in a real way, through the analysis of information corresponding to the deposition of a real paint material, for example and in a non-limiting way, through the analysis of the shape, volume or composition properties of a real paint coating (4) deposited, in one or several layers successively, on a physical workpiece (T).

[0098] Other parameters detected by the configurator (6) may comprise, in other preferred embodiments of the invention, information relating to the position or movement of the physical tool (1') (such as, for example, the working angle, the displacement angle, the displacement speed, or the working distance between the physical tool (T) and the physical workpiece (2'), and / or its corresponding simulated elements.

[0099] The paint spray calculator (7) is configured to calculate the shape and volume of the paint coating (4) from the input paint parameters processed by the configurator (6). Preferably, said calculation is performed for each layer (3) of simulated paint material.

[0100] The renderer (8) is configured to generate realistic or photorealistic image information from two-dimensional (2D) or three-dimensional (3D) models in a simulation environment. 2D or 3D rendering techniques from models are generally known in the state of the art.

[0101] The display (9) is configured to represent and display the image information generated by the renderer (8). To this end, the display (9) may comprise, in different embodiments of the invention, a monitor or a screen, optionally a touch screen. In other embodiments of the invention, the display (9) may be integrated into a painting mask or helmet adapted to be worn by the user of the simulation equipment (5), or integrated into the physical workpiece (T) itself. The simulation equipment (5) is preferably communicatively connected (either wired or wirelessly) to a position detector (10), adapted to receive information corresponding to the position and orientation of the physical workpiece (T) and / or the physical tool (2').Said position detector (10) may comprise, by way of non-limiting example, one or several cameras and / or, in other embodiments, other detection means such as inertial sensors (with which, in addition, it is possible to infer the position / obtention of the physical work piece (T) and / or the physical tool (2') with respect to the direction and sense of the force of gravity), haptic, thermal, mechanical, electromagnetic, etc. Thus, in general, the method of the invention comprises:

[0102] - obtain, with the position detector (10), information corresponding to the spatial location of the physical workpiece (T) and the physical tool (2'), and send said spatial location information to the simulation equipment (5); and / or

[0103] - calculate, with the position detector (10) and / or with the simulation equipment (5), the position and orientation of the physical workpiece (1') and the physical tool (2'), from the information obtained by the position detector (10);

[0104] Likewise, in a preferred embodiment of the invention, the simulation method comprises the operation of a physical workpiece (T) and / or a physical tool (2'), where said workpiece (1') and / or said tool (2') comprise one or more position indicators (11) (see Figure 3), which can be detected by the position detector (10). The position indicators (11) comprise, for example, optical markers such as LEDs, QR codes, barcodes, retroreflective spheres, and / or printed markers; as well as natural markers such as characteristic points of the workpiece (T) and / or the tool (2') (for example, the corners of said elements can be used as characteristic points, without the need to arrange external marking or identification elements on them).The use of natural markers also includes techniques based on SLAM (Simultaneous Localization And Mapping). Alternatively, it is also possible to use artificial intelligence or machine learning techniques, for example through neural networks, where the acquired and / or generated images are obtained by comparing or calculating them from a supervised or unsupervised training data set. In these cases, the use of position indicators (11) is not essential for the invention. In this embodiment, based on position indicators (11), the method of the invention additionally comprises performing the following steps:

[0105] - obtain, with the detector (10), information corresponding to the location of the physical workpiece (T) and / or the physical tool (2') by means of the identification of the position indicators (11);

[0106] - determining, with the detector (10), the position and orientation of the physical workpiece (T) and / or the physical tool (2'), obtaining information about at least one of the following elements: a part of the physical workpiece (T) and / or the physical tool (2') that are visible in a field of view; the distance between the detector (10) and the physical workpiece (T) and / or the physical tool (2'), the location and orientation of the physical tool (2') relative to the physical workpiece (1'); the orientation of the physical workpiece (T) from the information of the detector (16); and

[0107] - represent, with the display (9), the simulation domain, based on the mapping of the position indicators (11) to positions on a simulated workpiece (1) and / or a simulated painting tool (2).

[0108] According to the above method, the step of determining, with the detector (10), the position and orientation of the physical workpiece (T) and / or the physical tool (2') preferably comprises obtaining information about at least one of the following: working angle, displacement angle, displacement speed, working distance between the physical workpiece (T) and / or the physical tool (2').

[0109] For any of the different preferred embodiments described above, the method of the invention comprises carrying out, with the simulation equipment (5), the following steps, in any technically possible order: i) Establishing, with the paint configurator (6), one or more input paint parameters that characterize the operation carried out by a user with the physical tool (2'), where said parameters comprise at least one of the following: composition of deposited paint, type of painting process, paint and / or air output flow, paint output fan opening.

[0110] ¡i) Rendering, with the renderer (8), at least one simulation domain in which the simulated paint coating (4) is represented in a three-dimensional painting space, and at least one of a simulated workpiece (1) and a simulated painting tool (2) that represent, respectively, the physical workpiece (T) and the physical tool (2') within said three-dimensional painting space.

[0111] Advantageously, the method of the invention essentially comprises the following additional steps: iii) Calculating, with the paint spray calculator (7), a paint projection surface (12) on the simulated workpiece (1), from the position and orientation of the physical workpiece (T) and the physical tool (2'), as well as from the input parameters, for each layer (3). Typically, the projection surface (12) will be determined as the intersection between the simulated paint emission cone or fan and the surface of the simulated workpiece (1) (Figure 4) although, in different embodiments of the invention, it can be calculated in relation to or from the perspective of the simulated workpiece (1), or in relation to or from the perspective of the simulated painting tool (2), both superficially and volumetrically.Preferably in the invention, the paint projection surface (12) is configured as one or more paint accumulation regions (13), where said accumulation regions (13) are determined, with the paint spray calculator (7), as a function of the output flow of paint and / or air established with the paint parameter configurator (6). iv) Solving, with the paint spray calculator (7), the shape and the volume of the paint coating (4) from the input paint parameters, where said shape and said volume are calculated as functions of deposition of paint material, on the one or more interconnected paint projection surfaces (12) that, together, configure the paint coating (4).v) Render, with the renderer (8), the paint coating (4) in the simulation domain and / or represent, with the visualizer (9), the simulated workpiece (1), the simulated painting tool (2) and the rendered paint coating (4).

[0112] As previously described, the paint projection surface (12) is advantageously configured in the invention as one or more paint accumulation regions (13), said accumulation regions (13) being determined, with the paint spray calculator (7), as a function of the paint and / or air output flow established with the painting parameter configurator (6). The paint accumulation regions (13) correspond, in actual spray painting operations, to deposition patterns that are configured as a function of the regulation of the air pressure or of the paint itself in an actual painting tool. Thus, when said pressure is suitably regulated, the deposition pattern will ideally have a substantially elliptical shape.However, when the outlet pressure of the air or of the paint itself is excessive at the nozzle, the elliptical pattern is modified, generally becoming a pattern of two regions (13) of paint accumulation. This situation, in different configurations, is represented in Figure 5. In a novel way, the present invention takes into account the effect of the pressure and the outlet flow of air and / or paint, to realistically simulate the patterns of the aforementioned accumulation regions (13).

[0113] In another preferred embodiment of the invention, in the step of solving, with the paint spray calculator (7), the shape and volume of the paint coating (4) from the input parameters, the paint material deposition functions are globally or locally decreasing functions from the centers of the accumulation regions (13). In this context, “globally or locally” will be understood as corresponding to the substantially central region of the paint projection surface (12) as a whole, or to the center of the accumulation regions (13).

[0114] In another preferred embodiment of the invention, the step of working out, with the paint spray calculator (7), the shape and volume of the paint coating (4) from the input parameters for each of the layers (3) of paint material comprises generating one or more paint dispersion patterns. In this context, the dispersion pattern will be understood as the effect of the distance between the simulated workpiece (1) and the simulated tool (2) on the dispersion of the paint, when it reaches the simulated workpiece (1). Thus, as the distance increases, the dispersion will be greater with respect to the global or local centers of the paint projection surface (12).

[0115] In another preferred embodiment of the invention, the step of solving, with the paint spray calculator (7), the shape and volume of the paint coating (4) from the input parameters for each of the layers (3) of paint material, comprises the generation of one or more roughness, dripping and / or displacement patterns of paint deposited on the simulated workpiece (1) (see Figure 6). By means of this effect, it is possible to achieve a much more realistic visual effect in the coating (4) finally generated in the simulated painting operations. In general, the techniques for implementing roughness or dripping textures are known in the field of computer-implemented graphics engines, although they are considered novel in terms of their application to the specific field of the invention.

[0116] In another preferred embodiment of the invention, the step of calculating, with the paint spray calculator (7), a paint projection surface (12) on the simulated workpiece (1), from the position and orientation of the physical workpiece (T) and the physical tool (2'), comprises a correction of the shape and / or the position of said projection surface (12) by the effect of gravity, by the effect of turbulence, by the effect of resistance or drag of air molecules, by the effect of temperature and / or ambient humidity, and / or by acceleration due to an air flow in one or more directions of three-dimensional space. An example of this correction is shown in Figure 7, where it can be seen how the trajectories of the simulated paint emission cone are curved by the effect of gravity, affecting the position of the paint projection surface (12) on the simulated workpiece (1).

[0117] In another preferred embodiment of the invention, the step of calculating, with the paint spray calculator (7), a paint projection surface (12) on the simulated workpiece (1), from the position and orientation of the physical workpiece (T) and the physical tool (2'), comprises one or more corrections determined as a function of the shape of the simulated workpiece (1). More preferably, said corrections comprise the determination of one or more occlusion regions (14) in the simulated workpiece (1), as shown by way of example in Figure 8. In general, the techniques for implementing occlusion regions (14) are known in the field of computer-implemented graphics engines, although they are considered novel in terms of their application to the specific field of the invention.

[0118] In another more preferred embodiment of the invention as described in the previous paragraph, the step of calculating, with the paint spraying calculator (7), a paint projection surface (12) on the simulated workpiece (1), from the position and orientation of the physical workpiece (T) and the physical tool (2'), comprises determining one or more occlusion regions (14) in the simulated workpiece (1) due to the existence of one or more virtual objects (15) arranged between the simulated workpiece (1) and the simulated painting tool (2), and / or arranged in the simulated workpiece (1) itself (see Figure 9).In automotive part painting simulation techniques, said occlusion regions (14) can be generated, for example, by the presence of simulated adhesive tape placed on the work piece (1), of one or more gripping elements of said simulated part (1), of elements present in the simulated part (1) itself, such as the handle or the opening handle of a door, etc.

[0119] In another preferred embodiment of the invention, the simulation method comprises performing, with the configurator (6), a step of parameterizing one or more surfaces of the simulated workpiece (1), where said parameterization comprises mapping (see Figure 10) of a data matrix (16) along said surfaces of the simulated workpiece (1), and where said data matrix (16) comprises a plurality of information cells (17), where each information cell (17) comprises one or more values ​​indicative of one or more geometric properties of the simulated workpiece (1), of an amount or a thickness of simulated paint deposited on a region of the simulated workpiece (1), of a fluidity of the paint deposited in a region of the simulated workpiece (1), and / or of a direction, sense and / or module of a velocity vector associated with a displacement of the paint deposited on the surface of the simulated workpiece (1).In a preferred embodiment of the invention, the direction, sense and / or magnitude of the velocity vector of the deposited paint is calculated from a simulation of the effect of the force of gravity applied to the paint on the surface of the simulated workpiece (1), along the data matrix (16). More preferably, the mapping of the data matrix (16) along the surfaces of the simulated workpiece (1) is a mapping such that each point or region of parameterization of the surfaces of the simulated workpiece (1) corresponds to a single cell (17) of information in the data matrix (16).Even more preferably, the parameterization comprises mapping a plurality of data matrices (16), and / or an n-dimensional data matrix (16) along the surfaces of the simulated workpiece (1), where the information in the information cells (17) of said matrices (16) has a different resolution between at least two of the data matrices (16), and / or between at least two dimensions of one or more of the data matrices (16).

[0120] As can be seen in Figures 10a-10b, the cells (17) of the data matrix (16) may have a square shape. However, in other preferred embodiments of the invention, said cells (17) may adopt other types of shapes, generally polygonal, such as triangular, hexagonal, etc. Thus, for example, Figure 11 of this document shows a surface of the simulated workpiece (1), mapped by means of a data matrix (16) of triangular cells (17) (Fig. 11). In other embodiments, it is also possible to combine different types of shapes / sizes of cells (17) in the same mapping, as considered most convenient for improving the calculations and / or for rendering the simulations. More preferably, the mapping follows a microgeometry methodology of the piece (1), that is, a reduction of the 3D area of ​​the mapping to a set of smaller geometric units, until reaching the appropriate resolution for the simulation.The microgeometry procedure makes it possible to avoid possible problems of texture discontinuity, as well as the appearance of texels (texture pixels) that can be broken, changing their shape and area and making it difficult to determine the continuity of the painting between cells (17), or regions of the same, mainly due to the movement or displacement of the painting on the surface of the piece (1).

[0121] In the present invention, once the tessellation of the piece (1) has been carried out and the level of detail necessary for the simulation has been reached, there are two possible preferred ways of rendering the painting on the piece (1), although without limitation to other techniques: a) Discretized mode: in this mode it is assumed that the geometric discretization generated is sufficient so that the movement jumps of the painting can be made appropriately from one geometric element to the adjacent one, assuming the precision errors that may be generated (since, although small, the jump between cells (17) will be discrete), below a certain error threshold. This mode is usually, in general, faster than others, although at the cost of minor losses of quality and the generation of some other visual artifact.b) Use of particles (18): this mode involves generating particles (18) directly on the surface of the piece (1) in the regions where paint deposition occurs and preferably using the barycentric coordinates of the cells (17) (whatever their shape or size) where the deposition occurs. In this way, each particle (18) is unequivocally linked to the surface of the piece (1) in its corresponding cell (17), and subsequently one or more physics (understood as displacement effects of the particles (18) by sliding, gravity, dripping, accumulation, etc.) are applied to generate their movement and, consequently, the final appearance of the paint deposited on the piece (1).More preferably, said physics can be applied considering the cells (17) as flat surfaces (for example, in the case of the triangles shown in Figures 11 and 12) and allowing the particles (18) to move within or between the cells (17), depending on how it is most convenient for the simulation results to be obtained.

[0122] Depending on the requirements or the computing power of the renderer (8), the cells (17) can be populated with different amounts of simulated paint particles (18). As an example, Figures 12a-12c show cells (17) with three particle aggregation densities (18) corresponding to, respectively, twenty particles, one hundred particles and one thousand particles. Furthermore, since the particles (18) move over the surface of the cells (17), the cells can act as local containers for the particles (18), which speeds up the particle interaction calculations and thus avoids the need to use a higher level of detail in the microgeometry.

[0123] On the other hand, the physics calculation treating the cells (17) as non-flat surfaces, or when the rendering is calculated in three dimensions (i.e. when the physics calculation is performed in real 3D) can also be incorporated when the particles (18) reach some geometric limit (for example, an edge of the piece (1)) and accumulate therein, or when they lose their cohesive capacity, for example when they come off due to the action of gravity. In these cases, the particles (18) come off the surface of the piece (1), their physics being treated independently of the deposited paint.

[0124] In another preferred embodiment of the invention, in order to maintain the quantity of particles (18) in each cell (17) stable during paint deposition, it is possible to establish minimum and maximum radii for said particles (18). In this way, when a quantity of particles (18) overlap in the same area of ​​the cell (17), they merge, reducing the total quantity of particles (18) and sharing or uniting their properties (for example by adjusting their radius, which will oscillate between the minimum and maximum values ​​established).

[0125] In another preferred embodiment of the invention, the simulation method additionally comprises the step of carrying out, with the paint spray calculator (7), a step of verifying the conservation of the mass of the simulated paint generated by the simulated painting tool (2), in relation to the simulated paint deposited on the simulated workpiece (1). More preferably, the step of calculating, with the paint spray calculator (7), a paint projection surface (12) on the simulated workpiece (1), comprises determining one or more areas of paint loss on said projection surface (12), where the mass conservation verification is not fulfilled.

[0126] In another preferred embodiment of the invention, the step of working out, with the paint spray calculator (7), the shape and volume of the paint coating (4) from the input parameters for each of the layers (3) of paint material comprises determining a value, a property or a transfer probability of the deposited paint on the simulated workpiece (1). Even more preferably, the value, property or transfer probability of the paint is determined as a function of an angle of incidence of the simulated paint on the simulated workpiece (1), of the distance between the simulated painting tool (2) and the simulated workpiece (1), and / or of an impact velocity of the simulated paint on the simulated workpiece (1).

[0127] In another preferred embodiment of the invention, the step of solving, with the paint spray calculator (7), the shape and volume of the paint coating (4) from the input parameters for each of the layers (3) of paint material, comprises the generation of one or more drying patterns of paint deposited on the simulated workpiece (1). In general, the techniques for implementing drying textures are known in the field of computer-implemented graphics engines, although they are considered novel in terms of their application to the specific field of the invention.

[0128] Finally, as described hereinbefore, the method of the invention can be applied to the simulation of any spray painting technique, such as

[0129] - painting by spraying with compressed air;

[0130] - painting by spraying with low-pressure compressed air; or

[0131] - painting by airless spraying. A second object of the invention relates to a computer program adapted to implement, in a simulation equipment (5), a method according to any of the embodiments described herein.

[0132] A third object of the invention relates to a system for simulating a spray painting operation, wherein said painting operation represents the application of one or more layers (3) of paint material onto a physical workpiece (T), and wherein said layers (3) of paint material form a paint coating (4); said system comprising:

[0133] - a physical tool (2') operable by a user;

[0134] - at least one position detector (10), adapted to receive information corresponding to the position and orientation of the physical workpiece (T) and the physical tool (2'); and

[0135] - a simulation device (5) connected to the physical tool (2') and to the position detector (10); said simulation device (5) being adapted with hardware and software means comprising a parameterization configurator (6), a paint spraying calculator (7), a renderer (8) and a display (9); and the hardware and / or software means of the simulation device (5) being adapted to perform the steps of a simulation method according to any of the embodiments described herein.

[0136] In a preferred embodiment of the invention, the physical tool (2') comprises an actual painting tool and / or a training painting tool. More preferably, the physical tool (2') may comprise or be connected to a robotic arm.

[0137] In a preferred embodiment of the invention, the system comprises:

[0138] - at least one position indicator (11) of a physical workpiece (T) and / or of the physical tool (2') and, additionally,

[0139] - and where the position detector (10) is adapted to receive information corresponding to the position of the physical workpiece (T) and / or the physical tool (2') by means of the position indicator (11). More preferably, the position indicator (11) comprises optical markers, printed markers and / or natural markers. Furthermore, the position detector (10) may comprise cameras, inertial sensors, haptic sensors, thermal sensors, mechanical sensors, and / or electromagnetic sensors.

Claims

CLAIMS 1.- Method for simulating a painting operation by spraying, where said painting operation represents the application of one or more layers (3) of paint material on a physical workpiece (T), and where said layers (3) of paint material configure a paint coating (4); where said method comprises the operation of: - a physical tool (2') operable by a user; - at least one position detector (10), adapted to receive information corresponding to the position and orientation of the physical workpiece (T) and / or the physical tool (2'); and - a simulation device (5) connected to the physical tool (2') and to the position detector (10); said simulation device (5) being adapted with hardware and software means comprising a paint parameter configurator (6), a paint spraying calculator (7), a renderer (8) and a display (9); said method comprising performing the following steps: - obtain, with the position detector (10), information corresponding to the spatial location of the physical workpiece (T) and the physical tool (2'), and send said spatial location information to the simulation equipment (5); - calculate, with the position detector (10) and / or with the simulation equipment (5), the position and orientation of the physical workpiece (T) and the physical tool (2'), from the information obtained by the position detector (10); - establishing, with the paint parameter configurator (6), one or more input parameters, which characterize a painting operation for one or more layers (3) of paint material, where said input parameters comprise at least one of the following: composition of the deposited paint material, type of painting process, paint and / or air outlet flow, opening of the deposited paint outlet fan; - rendering, with the renderer (8), at least one simulation domain in which a simulated workpiece (1) and a simulated painting tool (2) representing, respectively, the physical workpiece (T) and the physical tool (2') are represented within a three-dimensional painting space; and where the method is characterized in that it additionally comprises the following steps: - calculating, with the paint spray calculator (7), one or more paint accumulation regions (13), and where said accumulation regions (13) are determined, with the paint spray calculator (7), based on the paint and / or air output flow established with the paint parameter configurator (6); - solve, with the paint spray calculator (7), the shape and volume of the paint coating (4) from the input paint parameters; - render, with the renderer (8), the paint coating (4) in the simulation domain; - represent, with the display (9), the simulated workpiece (1), the simulated painting tool (2) and the rendered paint coating (4). 2.- Method according to the previous claim, where: - the paint accumulation regions (13) are determined by a paint projection surface (12) on the simulated workpiece (1), obtained from the position and orientation of the physical workpiece (T) and / or the physical tool (2'), as well as from the input parameters, for each layer (3); and - the shape and volume of the paint coating (4) are calculated as functions of deposition of paint material onto the one or more accumulation regions (13) of the paint spraying surface (12) which, together for the applied layers (3), configure the paint coating (4).

3. Method according to any of the preceding claims, wherein, in the step of solving, with the paint spray calculator (7), the shape and volume of the paint coating (4) from the input parameters, the paint material deposition functions are globally or locally decreasing functions from the centers of the paint accumulation regions (13).

4. Method according to any of the preceding claims, wherein the step of solving, with the paint spray calculator (7), the shape and volume of the paint coating (4) from the input parameters for each of the layers (3) of paint material comprises the generation of one or more paint dispersion patterns.

5. Method according to any of the preceding claims, wherein the step of solving, with the paint spray calculator (7), the shape and volume of the paint coating (4) from the input parameters for each of the layers (3) of paint material comprises generating one or more roughness, dripping and / or displacement patterns of paint deposited on the simulated workpiece (1).

6. Method according to any of the preceding claims, wherein the step of solving, with the paint spray calculator (7), the shape and volume of the paint coating (4) from the input parameters for each of the layers (3) of paint material, comprises calculating one or more indicators relating to the properties of the paint deposited on the simulated workpiece (1), said indicators comprising one or more of the following: time used during the painting operation, efficiency of the transfer of deposited material, consumption of paint material, presence of defects.

7. Method according to any of claims 2-6, wherein the step of calculating, with the paint spray calculator (7), a paint projection surface (12) on the simulated workpiece (1), from the position and orientation of the physical workpiece (T) and the physical tool (2'), comprises a correction of the shape and / or the position of said projection surface (12) by the effect of gravity, by the effect of turbulence, by the effect of resistance or drag of air molecules, by the effect of temperature and / or ambient humidity, and / or by acceleration due to an air flow in one or more directions of three-dimensional space.

8. Method according to any of claims 2-7, wherein the step of calculating, with the paint spray calculator (7), a paint projection surface (12) on the simulated workpiece (1), from the position and orientation of the physical workpiece (T) and the physical tool (2'), comprises one or more corrections determined as a function of the shape of the simulated workpiece (1). 9.- Method according to the preceding claim, wherein the corrections determined based on the shape of the simulated workpiece (1) comprise the determination of one or more occlusion regions in the simulated workpiece (1).

10. Method according to any of claims 2-9, wherein the step of calculating, with the paint spray calculator (7), a paint projection surface (12) on the simulated workpiece (1), from the position and orientation of the physical workpiece (T) and the physical tool (2'), comprises determining one or more occlusion regions (14) in the simulated workpiece (1) due to the existence of one or more virtual objects (15) arranged between the simulated workpiece (1) and the simulated painting tool (2) and / or arranged on the simulated workpiece (1) itself.

11. Method according to any of the preceding claims, further comprising performing, with the parameterizer (6), a step of parameterizing one or more surfaces of the simulated workpiece (1), said parameterization comprising mapping a data matrix (16) along said surfaces of the simulated workpiece (1), and said data matrix (16) comprising a plurality of information cells (17), each information cell (17) comprising one or more values indicative of one or more geometric properties of the simulated workpiece (1), of an amount or a thickness of simulated paint deposited on a region of the simulated workpiece (1), of a fluidity of the paint deposited on a region of the simulated workpiece (1), and / or of a direction, sense and / or modulus of a velocity vector associated with a displacement of the paint deposited on the surface of the simulated workpiece (1). 12- Method according to the preceding claim, where: - one or more of the information cells (17) of the data matrix (16) have a square, triangular, hexagonal or polygonal shape; and / or where - the information cells (17) of the matrix (16) have different types of shapes and / or cell sizes (17). 13.- Method according to any of claims 11-12, wherein the step of rendering, with the renderer (8), the paint coating (4) in the simulation domain, comprises the generation of particles (18) directly on the surface of the piece (1), in the regions where the paint deposition occurs, associating said particles with corresponding information cells (17). 14.- Method according to the previous claim, where one or more physics are applied to the deposited particles (18) to generate their movement and / or the final appearance of the paint deposited on the piece (1). 15.- Method according to any of claims 13-14, wherein the cells (17) are populated with different amounts of simulated paint particles (18). 16.- Method according to any of claims 13-15, wherein a minimum and / or maximum radius of the particles (18) in the cells (17) is established. 17.- Method according to any of claims 11-16, wherein the cells (17) are flat. 18.- Method according to any of claims 11-17, wherein the direction, sense and / or module of the velocity vector of the deposited paint is calculated from a simulation of the effect of the force of gravity applied to the paint on the surface of the simulated workpiece (1), along the data matrix (16).

19. Method according to any of claims 11-18, wherein the mapping of the data matrix (16) along the surfaces of the simulated workpiece (1) is a mapping such that each point or region of parameterization of the surfaces of the simulated workpiece (1) corresponds to a single cell (17) of information of the data matrix (16).

20. Method according to any of claims 11-19, wherein the parameterization comprises mapping a plurality of data matrices (16), and / or an n-dimensional data matrix (16) along the surfaces of the simulated workpiece (1), where the information in the information cells (17) of said matrices (16) has a different resolution between at least two of the data matrices (16), and / or between at least two dimensions of one or more of the data matrices (16).

21. Method according to any of the preceding claims, which additionally comprises carrying out, with the paint spray calculator (7), a step of verifying the conservation of the mass of the simulated paint generated by the tool. (2) of simulated paint, in relation to the simulated paint deposited on the simulated workpiece (1). 22.- Method according to the preceding claim, wherein the step of calculating, with the paint spray calculator (7), a paint projection surface (12) on the simulated workpiece (1), comprises determining one or more areas of paint loss where the mass conservation verification is not fulfilled.

23. Method according to any of the preceding claims, wherein the step of solving, with the paint spray calculator (7), the shape and volume of the paint coating (4) from the input parameters for each of the layers (3) of paint material comprises determining a value, a property or a transfer probability of the paint deposited on the simulated workpiece (1).

24. Method according to the preceding claim, wherein the value, property or probability of transfer of the paint is determined as a function of an angle of incidence of the simulated paint on the simulated workpiece (1), of the distance between the simulated painting tool (2) and the simulated workpiece (1), and / or of an impact speed of the simulated paint on the simulated workpiece (1).

25. Method according to any of the preceding claims, wherein the step of solving, with the paint spray calculator (7), the shape and volume of the paint coating (4) from the input parameters for each of the layers (3) of paint material comprises generating one or more drying patterns of paint deposited on the simulated workpiece (1). 26.- Method according to any of the preceding claims wherein one or more of the input parameters comprise the type of painting process, and wherein said type of painting process comprises: - painting by spraying with compressed air; - painting by spraying with low-pressure compressed air; - painting by airless spraying. 27.- Computer program adapted to implement, in a simulation equipment (5), a method according to any of the preceding claims. 28.- A system for simulating a spray painting operation, wherein said painting operation represents the application of one or more layers (3) of paint material onto a physical workpiece (T), and wherein said layers (3) of paint material form a paint coating (3); said system comprising: - a physical tool (2') operable by a user; - at least one position detector (10), adapted to receive information corresponding to the position and orientation of the physical workpiece (T) and the physical tool (2'); and - a simulation device (5) connected to the physical tool (T) and to the position detector (10); said simulation device (5) being adapted with hardware and software means comprising a parameterizer (6), a paint spraying calculator (7), a renderer (8) and a display (9); characterized in that the hardware and / or software means of the simulation device (5) are adapted to perform the steps of a method according to any one of claims 1-26. 29.- System according to the preceding claim, wherein the physical tool (2') comprises: - a real painting tool, and / or - a training painting tool. 30.- System according to any of claims 28-29, wherein the physical tool (2') comprises a robotic arm. 31.- System according to any of claims 28-30, comprising: - at least one position indicator (11) of a physical workpiece (T) and / or of the physical tool (2') and, additionally, - and where the position detector (10) is adapted to receive information corresponding to the position of the workpiece (T) and / or the physical tool (2') by means of the position indicator (11). 32.- System according to the preceding claim, wherein the position indicator (11) comprises one or more of the following: optical markers, printed markers and / or natural markers. 33.- System according to claims 28-32, wherein the position detector (10) comprises one or more of the following: cameras, depth cameras, inertial sensors, haptic sensors, thermal sensors, mechanical sensors, electromagnetic sensors, laser sensors.

Images