Method for controlling a laying head of a tire assembly with path simplification

Abstract

The present invention relates to a method for defining a path of a laying head (1) for laying a tyre assembly on a core (4), comprising a step (a) of geometrically characterizing a profile in which a first set of geometrically significant points (PP1,...PPn) is provided which represent the shape of the profile (10), a step (b) of functionally characterizing the profile in which a second set of functionally significant points (PF1,...PFm) is provided which are associated with laying rules which specify laying conditions of the tyre assembly and which are stored in a path table, a step (c) of gridding in which a series of equidistant virtual points called "potential guide points" (PG1,...PGp) is defined on the profile (10) from the first functionally significant point (PF1) to the last functionally significant point (PFm), followed by a step (d) of simplification in which the size of the path table is reduced by applying one or more selection criteria to the path table so as to select a portion of the potential significant points (PGk) and of the significant points (PPi, PFj).

Description

Technical Field

[0001] This invention relates to the field of manufacturing tires for wheels, and more particularly, to the field of controlling a laying head designed for laying tire assemblies by winding it around a core-shaped or drum-shaped rotating manufacturing support. Background Technology

[0002] Tires (especially pneumatic tires) are known to be manufactured by spirally winding multiple tire components around a core with a curved profile having an annular shape. The tire components include one or more continuous strips of raw rubber (i.e., uncured rubber), such as raw rubber strips intended to form the tread of the tire, or one or more reinforcing strips containing continuous reinforcing threads oriented parallel to the longitudinal direction of the reinforcing strip to form one or more reinforcing bands.

[0003] In this regard, it is known to utilize a robotic arm carrying a laying head designed to transport and lay the tire assembly under consideration onto the core. Naturally, the robotic arm then needs to be controlled to position, orient, and move the laying head accordingly along the contour of the core, following a suitable laying path.

[0004] In this regard, it is sometimes difficult to find a good compromise between laying accuracy (which needs to be multiplied by the points used to define the laying path) and the storage and computer processing power of the control unit that controls the robotic arm (which is not always able to manage large amounts of data in real time).

[0005] Admittedly, smoothing algorithms are also known, which can replace continuous contour points (especially by Bézier curves) with path curves modeled by parametric polynomial functions, which allow for simplified approximations of the contour. The main advantage of such Bézier curves is their continuity of curvature, resulting in smooth path curves.

[0006] However, this smoothing algorithm requires relatively high computing power and is unsuitable for managing certain types of robotic arms, especially certain types of six-axis anthropomorphic robotic arms, because these arms cannot handle Bézier curve-type setpoints and can only be operated through "segmented" servo control, that is, through setpoints represented in the form of a path table, which lists in a finite number of consecutive points that constitute the path to be followed. Summary of the Invention

[0007] Therefore, the subject matter related to this invention aims to overcome the above-mentioned shortcomings and propose a new method for defining the path of a laying head intended for laying tire assemblies on a core, which allows for segmented and real-time servo control of the laying head with moderate computer processing power, while still ensuring satisfactory accuracy and quality of the laying operation.

[0008] The subject matter related to this invention is achieved by a method for defining the path of a laying head and a corresponding method for controlling the laying head, the laying head being designed to lay at least one tire assembly by looping the tire assembly around a receiving surface of a core rotating about its central axis, the receiving surface having a predetermined profile along the central axis, the method comprising:

[0009] - Step (a) of the geometric representation of the contour, in which the contour lines of the receiving surface are provided, and a first set of salient points called "geometric salient points" are separated on the contour, these points being considered as features of the shape of the contour, and the geometric salient points are stored in the form of a set of path points called a "path table".

[0010] - Step (b) of the functional characterization of the profile, in which multiple functional zones are defined on the profile, each functional zone extending from a region start point to a region end point, and a paving pattern is associated with each of the functional zones, the paving pattern specifying the conditions for paving the tire assembly in the considered functional zones, and the region start point and the region end point forming a second set of salient points called "functional salient points" are inserted into the path table.

[0011] - The next step is the meshing step (c), in which, referring to the predetermined direction of travel of the contour, a series of equidistant virtual points called "potential guide points" are defined on the contour, from the first functional salient point (i.e., the point starting from the first functional area, which is considered the origin) to the last functional salient point (i.e., the point ending at the last functional area). These potential guide points are paired to delineate all line segments with the same length, equal to a predetermined selection value called the "unit resolution spacing," and the potential guide points are inserted into the path table.

[0012] - This is followed by a simplification step (d), in which at least a portion and only a portion of the potential guide points and geometrically and functionally significant points contained in the path table are selected by applying one or more selection criteria to the path table, and the size of the path table is reduced by deleting unselected points to obtain a reduced-size simplified path table in which the length of at least one, preferably several, line segments connecting pairs of consecutively selected points is strictly greater than the selected unit resolution spacing.

[0013] Advantageously, the method according to the invention makes it possible to clearly identify, and therefore appropriately consider, salient points that require special attention, whether defining the geometry of the profile (particularly in sections of the profile having specific geometric singularities such as pronounced curvature) or highlighting functional singularities (in this case, variations in the paving pattern), for example when the spacing of the tire components or the winding speed is modified.

[0014] Furthermore, due to the multiple potential guiding points, the mesh originally proposed by this method offers the possibility of having a particularly fine mesh when needed.

[0015] Therefore, depending on the situation of the relevant outline portion, it can be done locally:

[0016] - By maintaining a high density of selected points to preserve fine resolution, and by using short line segments with a length equal to the unit resolution spacing to maintain and utilize the fineness of the mesh, good tiling accuracy is ensured for the relevant contour portions; this will typically apply to portions of the contour where there are geometric or functional singularities (more specifically, in detail, near salient points);

[0017] - Alternatively, conversely, by selecting and retaining only a portion of the potential guide points from all available potential guide points in the relevant contour section, and thus by extending the line segments separating two consecutive path points in that contour section, the grid is "relaxed," i.e. the grid density is reduced. This would typically be applicable to parts of the contour with less variability, particularly where the direction of the contour lines changes little or not at all, and where the tiling pattern has a certain degree of constancy.

[0018] As an indication, the density of the selected points can be increased, thus defining shorter line segments in the parts of the profile that correspond to changes in the paving pattern, and in the parts where the direction of the profile changes significantly, curves sharply, and therefore has a small radius of curvature (especially in the tire shoulder, i.e., the transition region between the tire crown that forms the tread and the tire sidewall that connects the crown to the rim). Conversely, the selected points can be spaced out, thus lengthening the line segments (especially in the tire crown, which is almost flat and corresponds to the tread).

[0019] Finally, through this invention, a path table can thus be prepared and subsequently sent to a robotic arm. This path table will be particularly lightweight because it contains a relatively small number of points that are ultimately selected. However, the selected points will be distributed in such a way that they are concentrated in the most complex and difficult-to-create parts of the profile to have a denser grid, thereby ensuring the greater precision required in these parts, and conversely, they are more spaced out to reduce the grid density in simpler parts where lower precision is permissible in path control. Attached Figure Description

[0020] Other subjects, features, and advantages of the invention will become more apparent from the following description, aided by the accompanying drawings, which are provided by way of non-limiting illustration only, wherein:

[0021] Figure 1 A top view shows a tire manufacturing apparatus capable of implementing the method according to the invention.

[0022] Figure 2 An example of the profile of the receiving surface of the core is shown, which corresponds to a section passing through the receiving surface in the meridional plane of the core containing the central axis of the core, and several geometrically significant points are identified on the profile.

[0023] Figure 3 A schematic diagram showing the outlines of the identified geometric and functional salient points is displayed.

[0024] Figure 4 The diagram illustrates the meshing step, in which a series of equidistant potential guide points are used to mesh the mesh. Figure 3 The outlines are filtered.

[0025] Figure 5 This demonstrates the application of the first selection criterion during this period. Figure 4 Select potential guide points around the salient points on the outline.

[0026] Figure 6 The schematic diagram illustrates the principle of the second selection criterion based on the allowable deviation limit. According to this principle, it is ensured that for every three selected points, the two adjacent line segments connecting the consecutively selected points in pairs do not deviate from the corresponding interpolation circle by more than the predetermined allowable deviation value.

[0027] Figure 7 The application shows a second selection criterion based on the allowable deviation limit, and the corresponding selected points are added to... Figure 5 In the outline.

[0028] Figure 8 Showing the direction Figure 7 The contour application is based on a third selection criterion of the maximum allowed line segment length. According to this criterion, when a line segment connecting two selected points with a length exceeding the maximum allowed length value is detected, the intermediate potential guide point is added to the selection result.

[0029] Figure 9 Showing the direction Figure 8 The contour application is based on a fourth selection criterion of quality level, during which potential guide points adjacent to the selected points are added. Figure 8 In the selection results of the points.

[0030] Figure 10 This shows the application of the above selection criteria. Figure 3 The path is the path corresponding to the simplified path table obtained after outlining the contour. Detailed Implementation

[0031] The present invention relates to a method for defining the path of a laying head 1.

[0032] The laying head 1 is designed to lay at least one tire assembly 2 by wrapping the tire assembly 2 in loops (preferably in loops that are continuous or partially overlapping from one loop to another) around the receiving surface 4A of the core 4, which rotates about its central axis X4.

[0033] Tire assembly 2 can be a continuous raw rubber strip or a continuous filamentary reinforcing element, the length of which is much larger than its maximum lateral dimension, specifically at least 100 times or even 1000 times. The continuous filamentary reinforcing element can be formed, for example, by reinforcing wires or cords made of metal, glass fiber, or polymers selected according to their tensile strength (e.g., aramids), which may be coated with raw rubber. As a variation, the continuous filamentary reinforcing element can be formed by a reinforcing strip comprising several continuous reinforcing wires or cords made of metal, glass fiber, or polymers (e.g., aramids), which are arranged parallel to each other along the longitudinal direction of the strip and embedded in a matrix, for example, raw rubber or a resin optionally coated with a raw rubber surface coating.

[0034] The laying head 1 is carried by a robotic arm 5 that is movably mounted on a base 6.

[0035] The robotic arm 5 is preferably a six-axis anthropomorphic robotic arm. In a manner known per se, the robotic arm 5 includes a first joint (referred to as a “shoulder”) forming a connection between a base 6 and a first segment (referred to as an “arm”), the first segment further carrying (preferably including at least one pivot axis) a second joint (referred to as an “elbow”) to ensure angular bending movement of the arm relative to a second segment (referred to as a “forearm”), the end of the second segment carrying a third joint (referred to as a “wrist”), the third joint being movable along a pair of three orthogonal pivot axes, one of which is aligned with the longitudinal axis of the forearm, the wrist being designed to receive and carry the laying head 1.

[0036] The path of the robotic arm 5 (and therefore the laying head 1) is controlled by an appropriate automatic control unit (e.g., a programmable logic controller).

[0037] The core 4 is supported by a frame 7 called the "core frame" 7 and rotates about its central axis X4 relative to the core frame 7 by a suitable electric drive device, for which an electric motor is preferably provided.

[0038] Preferably, the device 8 according to the invention, including the core 4, the core frame 7, and the robotic arm 5, has several interchangeable laying heads 1, such as... Figure 1 As shown.

[0039] Each of the laying heads 1 can advantageously be provided with different tire assemblies.

[0040] Therefore, the robotic arm 5 can select the head 2 corresponding to the tire assembly to be laid, and if necessary, change the laying head 1 during the manufacturing cycle so that several tire assemblies can be laid continuously on the core 4.

[0041] The receiving surface 4A of the core has a predetermined profile 10 along the central axis X4, such as... Figure 2 As shown.

[0042] The profile 10 corresponds to the intersection of the receiving surface 4A and a section containing the central axis X4, known as the "meridian plane".

[0043] like Figure 1 and Figure 2 As shown, the core 4 preferably has a shape that rotates about its central axis X4 (more specifically, an annular shape), which makes the receiving surface 4A have an overall outwardly convex (in this case, a convex, curved shape) curved profile 10.

[0044] Preferably, the profile 10 includes a nearly flat central region corresponding to the tire crown 11, which will bear the tread and come into contact with the road. This central region is bounded at each axial end by curved regions with radii of curvature well below the values ​​of one or more radii of curvature of the tire crown 11. These curved regions correspond to the tire shoulders 12, 13, which form the transition between the tire crown 11 and the tire sidewall, which extends radially toward the central axis X4 before engaging with the rim.

[0045] According to the present invention, the method for defining a paving path includes a step (a) of geometric representation of profile 10, in which a profile line of profile 10 of receiving surface 4A is provided, and a first set of salient points PP1, PP2…, PPi…, PPn-1, PPn are separated on profile 10. This first set of salient points is called “geometric salient points” PP1, PP2…, PPi…, PPn-1, PPn. These points are considered to be features of the shape of profile 10 and thus represent profile 10. The geometric salient points PP1, PP2…, PPi…, PPn-1, PPn are stored in the form of a set of path points called a “path table”, such as… Figure 2 As shown.

[0046] The indicator “n” corresponds to an integer, and “i” represents the i-th point in a series of points, with the value of i ranging from 1 to 2. n between.

[0047] The path table includes at least the spatial coordinates of the geometrically significant points represented in a reference frame attached to the robotic arm 5 (more specifically, to the fixed base 6 attached to the robotic arm 5), relative to which the robotic arm 5 performs the movement of the laying head 1.

[0048] It is important to note that, in absolute terms, the path table (i.e., the set of waypoints) can take any suitable form; more specifically, it can take any suitable form of digital data storage, such as a list or table. Particularly preferred is that the path table take the form of a table, where each waypoint forms a row in the table.

[0049] In all cases, the path points (in this case, in particular the rows of the table) will preferably be arranged in an order in which the path points follow each other along the given direction of travel (denoted as FWD) of the outline 10, traveling from one end of the outline 10 to the other. In other words, in the path table, the path points included in the path table will preferably be ordered in the direction of the curve x-coordinate that increases along the outline 10.

[0050] Therefore, in this case, n The geometric salient points PPi are preferably stored in the path table in the form of consecutive rows, with each row corresponding to a salient point in order corresponding to the direction of travel (FWD).

[0051] Preferably, such as Figure 2 As shown, the smaller the radius of curvature of profile 10, the closer the geometric salient points PP1, PP2, ..., PPi, ..., PPn-1, PPn are, and therefore the shorter the adjacent segments of profile 10 defined by pairs of geometric salient points. Thus, in the sharply curved portions of profile 10 (e.g., tire shoulders 12, 13), more geometric salient points will be considered, forming a denser network, while in the straighter portions of the profile (e.g., tire crown 11), the geometric salient points will be spaced apart.

[0052] As an indication, particularly for the profile 10 with a total axial width W10 between 150 mm and 370 mm, the number of geometrically significant points is set. n Preferably between 20 and 60, more preferably between 30 and 40.

[0053] Therefore, it is important to note that in Figure 3 In the illustrative examples in the following figures, for the sake of simplicity, a deliberately shortened and simplified outline 10 will be used, on which only n=4 geometrically significant points PPI, PP2, PP3, and PP4 are identified.

[0054] According to the present invention, the method for defining a paving path further includes a step (b) of functional characterization of the profile 10, in which a plurality of functional zones are defined on the profile, each functional zone extending from a region start point to a region end point, and a paving pattern is associated with each of the functional zones, the paving pattern specifying the conditions for paving the tire assembly 2 in the considered functional zones, and the region start point and the region end point forming a second set of salient points PF1, PF2..., PFj..., PFm-1, PFm, referred to as “functional salient points” PF1, PF2..., PFj..., PFm-1, PFm, are inserted into the path table.

[0055] The indicator "m" corresponds to an integer, while "j" represents the j-th point in a series of points, with the value of j ranging from 1 to... m between.

[0056] Typically, it can provide up to 20, 25, or even 30 functional areas. In fact, m It can be between 3 and 30, more preferably between 5 and 10.

[0057] Preferably, in step (b) of the functional characterization of the profile, the paving pattern is associated with each functional zone, which characterizes the conditions for paving the tire assembly in the considered functional zone by specifying at least one paving parameter (preferably several paving parameters, more preferably all paving parameters) with a value that is applicable and constant in the considered zone:

[0058] (i) The nature of tire assembly 2; for example, it can be specified whether to lay raw rubber strips, reinforcing lines, or reinforcing strips;

[0059] (ii) Laying pitch, the laying head 1 is offset relative to the core 4 along the central axis between two consecutive loops according to the laying pitch; the laying pitch corresponds to the movement of the laying head along the contour of each full loop of the core, and thus corresponds to the spacing of the helix formed on the core by the tire assembly under consideration, and, for example, the degree of axial overlap between two consecutive loops of the rubber strip or reinforcing strip can be defined by means of the laying pitch parameter, and thus the radial thickness of the layer produced by the winding of the loops can be controlled; it should be noted that, from an absolute point of view, it is conceivable to move the core 4 axially relative to the core frame 7 in order to produce a relative axial movement of the core 4 relative to the laying head 1; however, the core 4 is preferably axially fixed, and the relative axial movement produced solely by the movement of the laying head 1 will therefore be able to define and control the laying pitch;

[0060] (iii) Laying speed, which corresponds to the circumferential speed at which the tire assembly 2 is wound around the core 4 on the core, and / or

[0061] (iv) Laying tension, which corresponds to the longitudinal tension applied within the tire assembly 2 during laying under the traction of the rotating core 4.

[0062] In fact, the functional salient points PF1, PF2, ..., PFj, ..., PFm-1, PFm will mark the boundary along contour 10 where the execution of the tiling rule begins, the execution of the tiling rule ends, or the transition occurs between the first tiling rule and a second tiling rule different from the first tiling rule (more specifically, a second tiling rule that modifies the value of at least one or more tiling parameters relative to the first tiling rule preceding it).

[0063] Furthermore, the laying pattern will, for example, establish a relationship between the angular position and / or angular velocity of the core 4 relative to its central axis X4 and the position and position evolution of the laying head 1 along the contour 10 by specifying the laying spacing, so as to allow the laying head 1 to servo the movement of the movement of the core 4 according to the angular position of the core 4.

[0064] For convenience, the laying patterns (and therefore the functional salient points PFj that characterize them) can be initially defined with reference to the abscissa of the profile 10. This is equivalent to virtually considering the profile 10 in the form of a straight line unfolding (i.e., in the form of a virtual line segment) and setting the functional salient points PFj as a number of markers on the virtual line segment. Subsequently, the spatial coordinates of the functional salient points PFj will be determined by performing a reverse operation, i.e., by applying the unfolding form carrying the points to the actual curved profile of the profile 10.

[0065] It is important to note that, in Figure 3 In the illustrative example, only m=3 functional salient points PF1, PF2, PF3 are considered, which are represented by short lines perpendicular to the contour. The first functional salient point PF1 forms the starting point for entering the first functional area and starting to lay the tire assembly 2 on the core 4 according to the first laying rule. The second functional salient point PF2 indicates entering the second functional area. The feature is that the laying parameters are modified (e.g., the laying spacing is reduced) so that the second laying rule is applied from the second functional salient point PF2. The third and final functional salient point PF3 indicates the arrival point at the end of the laying operation, which is at the end of the second functional area, and therefore according to the second laying rule.

[0066] It should be noted that, from an absolute perspective, one or more functional salient points PFj may correspond to one or a corresponding portion of geometric salient points PPi. However, preferably, at least a portion of the functional salient points PFj (if necessary, more than half of the functional salient points PFj, or even all of the functional salient points PFj) will, in principle, differ from the geometric salient points PPi, provided that the definition of the paving pattern and the adjustment of the continuous paving pattern (e.g., regarding the selection of tire assembly 2 or the start or end position of the paving of said tire assembly) can actually be associated with positions on profile 10 that do not correspond to points that define profile 10 purely geometrically.

[0067] Furthermore, although consecutive functional areas can be adjacent in a manner that continuously covers the outline 10, in certain manufacturing cycles, a portion of the outline 10 referred to as a "coverage interruption area" may be set between two portions of the outline 10 that must be covered by one or more tire components. This portion must not be covered by any tire component in the manufacturing cycle under consideration. In this case, there is a corresponding interruption interval between the two functional areas that are immediately before and after the coverage interruption area, respectively, so that the consecutive functional areas are not actually adjacent.

[0068] For ease of description and brevity, the general complex expression “salient point” or “geometric and functional salient point” can be used to refer indiscriminately to a geometrically salient point PPi and a functionally salient point PFj, and more specifically to any set that combines or may combine geometrically salient points PPi and functionally salient points PFj. Similarly, the general expression “salient point” or “geometric or functionally salient point” can be used to refer to a salient point alone, which, depending on the context, can be either a geometrically salient point PPi or a functionally salient point PPj.

[0069] According to the present invention, after identifying geometric and functional salient points PPi, PFj, the method for defining the paving path next includes a meshing step (c), in which, referring to a predetermined direction of travel of the profile (in this case denoted as FWD), a series of equidistant virtual points PG1, PG2…, PGk…, PGp-1, PGp are defined on the profile 10 from the first functional salient point PF1 (i.e., the point starting from the first functional area which is considered the origin) to the last functional salient point PFm (i.e., the point ending at the last functional area). These virtual points are called "potential guide points" PG1, PG2…, PGk…, PGp-1, PGp. These points are paired to delineate all line segments with the same length, which is equal to a predetermined selection value called the "unit resolution spacing" P_unit, as shown below. Figure 4 As shown, the potential guide points PG1, PG2, ..., PGk, ..., PGp-1, PGp are inserted into the path table.

[0070] The indicator “p” corresponds to an integer, and “k” represents the k-th point in a series of points.

[0071] Preferably, the unit resolution spacing P_unit of the potential guide points PG1, PG2..., PGk..., PGp-1, PGp generated in the meshing step (c) is between 0.1 mm and 1 mm, for example, equal to 0.5 mm.

[0072] Such a value can actually achieve sufficiently fine resolution and thus sufficient accuracy in the geometrically most complex parts and / or the most difficult functional areas of contour 10, and even more so in the simpler parts of contour 10. Therefore, this value will correspond to the best accuracy that this method can provide.

[0073] As an indication, taking into account the unfolded length of contour 10 and the envisioned unit resolution spacing P_unit, the initial number of potential guide points (i.e., the number p) generated by the “original” meshing operation can be between 500 (five hundred) and 8000 (eight thousand), for example, between 2000 and 5000.

[0074] At this stage, at the end of the meshing step (c), a "raw" path table is obtained, which temporarily contains all geometrically salient points PPi, all functionally salient points PFj, and all potential guide points PGk, in any case.

[0075] As an indication, the original path table can therefore have at least 500 points, at least 1,000 (one thousand) points, or even at least 2,000 (two thousand) points, and sometimes as many as 8,000 (eight thousand) path points.

[0076] However, as mentioned above, in practice, it is not necessary to maintain such a uniform initial meshing across the entire contour 10, resulting in a very fine mesh equal to or even locally smaller than the unit resolution spacing P_unit. In fact, as long as there are no significant changes affecting the contour lines or tiling patterns of contour 10, a less fine resolution can be used in portions of contour 10 where the orientation and tiling patterns change little or not at all, and therefore a larger spacing can be used.

[0077] Of all the potential guide points PGk that are initially available and temporarily inserted into the path table, and more generally, of all the potential guide points PGk that exist in the path table and thus constitute as many available path points as possible, as well as the geometric PPi and functional PFj salient points, some will therefore be effectively retained to form part of the final simplified path table 20, while others will not be retained, depending on their effectiveness.

[0078] This is why, following the meshing step (c), according to the invention, the method for defining the paving path further includes a simplification step (d), in which the size of the path table is reduced by applying one or more selection criteria to the path table to select at least a portion and only a portion of the potential guide points PGk and geometrically and functionally significant points PPi, PFj contained in the path table, and by deleting unselected points, to obtain a reduced-size simplified path table 20, as shown below. Figure 10 As shown, in this simplified path table, the length of at least one, preferably several (straight lines) connecting consecutively selected points in pairs is strictly greater than the selected unit resolution spacing P_unit.

[0079] It should be noted that in practice, the path points corresponding to singularities in contour 10 or the paving pattern, more specifically, the potential guide points PGk, will be preserved in order to concentrate the accuracy (and thus the available computational power) on the parts of contour 10 where it is truly needed.

[0080] From a formal perspective, the application of each selection criterion can be considered a sub-step of the simplification step (d).

[0081] As is customary, and for convenience in the accompanying diagrams, the potential guide point PGk is... Figures 3 to 10 The points are drawn with dashed lines, and the points that are actually selected (and therefore appear in the path table at the time being considered) are represented by small hollow solid circles. Arrows indicate points that are added to the selection results (also known as the "list of selected points") in the considered sub-steps, based on the applied selection criteria.

[0082] Preferably, in the simplification step (d), the selection criteria are applied based on the surrounding area (in this case, the first), such as... Figure 5 As shown, according to the selection criteria, the first functional salient point PF1, considered as the starting point Pstart of the paving path, is selected, and the last functional salient point PFm, considered as the destination point Pend of the paving path, is selected. Furthermore, for at least one geometric or functional salient point PPi, PFj strictly between the starting point Pstart and the destination point Pend, more preferably for each geometric or functional salient point PPi, PFj strictly between the starting point Pstart and the destination point Pend, in other words, here... Figure 5In the example, in the order of PF2, PP2, PP3, among the two potential guide points PGk surrounding the geometric or functional salient points PPi and PFj, that is, among the potential guide points immediately before and immediately after the geometric or functional salient points PPi and PFj, at least one of the two potential guide points PGk is selected, for example, the one of the two guide points PGk that is closest to the considered geometric or functional salient points PPi and PFj.

[0083] More preferably, for at least one salient point PPi, PFj located strictly between the starting point Pstart and the destination point Pend, or correspondingly for each salient point PPi, PFj located strictly between the starting point Pstart and the destination point Pend, each of two potential guide points PGk around the considered geometric or functional salient point PPi, PFj is selected, that is, one immediately preceding the geometric or functional salient point PPi, PFj and the other immediately following the geometric or functional salient point PPi, PFj.

[0084] exist Figure 5 In this case, it is equivalent to selecting PG5 and PG6 around PF2, then selecting PG12 and PG13 around PP2, and then selecting PG21 and PG22 around PP3.

[0085] Therefore, by selecting two potential guide points PGk located on either side of the considered salient points PPi and PFj along contour 10, it is possible to obtain a precise and balanced smoothness of the contour portion where the salient points PPi and PFj are located.

[0086] Advantageously, such a choice would allow the salient points PPi, PFj to be replaced by a corresponding pair of potential guide points PGk without causing any significant errors in following contour 10 and paving rules.

[0087] In this regard, it should be noted that, preferably, after selecting potential guide points based on the selection criteria, or preferably selecting potential guide points PGk around geometrically or functionally significant points PPi and PFj located strictly between the starting point Pstart and the destination point Pend, the considered geometrically and functionally significant points PPi and PFj are deleted.

[0088] More preferably, according to the first selection criterion, all geometrically and functionally significant points PPi, PFj located strictly between the starting point Pstart and the destination point Pend will be surrounded by one (or preferably two) potential guide points PGk, thus causing all said geometrically and functionally significant points PPi, PFj located strictly between the starting point Pstart and the destination point Pend to be ultimately deleted.

[0089] The above deletion is equivalent to "deselecting" all salient points PPi and PFj considered around the selection criteria, and thus removing at least a portion (preferably all) of the geometrically and functionally salient points PPi and PFj that lie strictly between the starting point Pstart and the destination point Pend from the path table.

[0090] Advantageously, such deletion is possible because of the fact that the potential guide points (or more likely two potential guide points) PGk selected near each considered geometric or functional salient point PPi, PFj are chosen from two potential guide points PGk surrounding the salient points PPi, PFj, and both potential guide points PGk are very close to the salient points, in this case, the distance is strictly less than the unit resolution spacing P_unit, so that it is not necessary to maintain the salient points PPi, PFj to meet the required accuracy. Specifically, once one or more potential guide points PGk are thus selected, the geometric or functional salient points PPi, PFj, which are the origin of this selection, become redundant in terms of the definition of the tiling path and can therefore be deleted without the risk of distorting the path or tiling regularity.

[0091] By applying a minimum separation gap between two consecutive points (in this case, by applying a minimum distance equal to the unit resolution gap P_unit between the two potential guide points PGk thus selected), the removal of the salient points PPi and PFj "surrounded" by the potential guide points PGk also ensures that the control unit (more specifically, the computer controlling the robotic arm 5) can indeed sense all the points used as consecutive setpoints in the path table in terms of its refresh rate when the laying head 1 moves, so that the servo control of the robotic arm 5 is not disturbed by excessive proximity between the two points.

[0092] Preferably, the salient points PPi and PFj surrounding the selected potential guide point PGk are immediately deleted, so that after applying the surrounding selection criterion, the salient points PPi and PFj no longer participate in the selection of subsequent path points.

[0093] Furthermore, since the final functional salient point PFm rarely coincides perfectly with one of the virtual guide points PGk, and also because it is desirable to ensure the accuracy of the end of the laying operation (in particular, to avoid overly abrupt deceleration that might exceed the set point or lay head 1), it is preferable that the virtual guide point PGk immediately preceding the final functional salient point PFm is still selected according to the same surrounding criteria (in this case, therefore for Figure 5 In PG29), it also retains the final functional salient point PFm that constitutes the arrival point Pend as described above.

[0094] Preferably, in the simplification step (d), and more preferably after applying the first surrounding selection criterion described above, a second selection criterion is applied (in this case, a second selection criterion), namely, a selection criterion based on the allowable deviation limit, according to said selection criterion, for every three selected consecutive points (e.g. Figures 5 to 7 For each pair of adjacent line segments defined by the three points PG13, PG21, and PG22, consider the interpolation circle Ck passing through the three points, and for each of the two line segments 21 defined by two consecutive points of the three points, calculate the deflection D between the line segment 21 forming the arc chord 21 and the arc 22 corresponding to the interpolation circle of the line segment 21, that is, the maximum measured distance D perpendicular to the line segment 21 and separating the arc 22 from the line segment 21, such as... Figure 6 As shown, and if the deflection D calculated for the line segment 21 exceeds the predefined maximum permissible deviation value Dmax, then one of the intermediate potential guide points PGk, or the intermediate potential guide points PGk located between the potential guide points forming the ends of the line segment 21 under consideration, is added to the list of selected points, such as... Figure 6 and Figure 7 visible.

[0095] Preferably, the potential guide point PGk that is closest to the middle of the line segment 21 under consideration is added to the list of selected points.

[0096] exist Figure 6 and Figure 7 In the example, it is the potential guide point PG17.

[0097] Advantageously, path points can thus be added, and the corresponding deviation can be reduced to zero precisely at or at least close to the location where the deviation between the arc 22 of the interpolated circle and the line segment 21 of the arc chord is initially the largest.

[0098] Of course, after adding a point to the selection results, the allowable deviation limit selection criteria can be repeated to ensure that the new division of the line segment including the added point meets the criteria, and if necessary, a new point can be added to ensure that the line segment (arc chord) is close enough to the interpolated circle.

[0099] Therefore, it will be ensured that the path formed by the polyline consisting of a set of selected points (and thus the path formed by a series of adjacent line segments connecting these selected points in pairs) will always be close enough to the actual contour line of contour 10, and thus constitute an acceptable approximation of the contour 10.

[0100] Preferably, the maximum permissible deviation value Dmax will be selected as one-quarter of the unit resolution spacing: Dmax = P_unit / 4.

[0101] This will ensure that the path of the line segment does not deviate significantly from contour 10.

[0102] Preferably, in the simplification step (d), more preferably, after applying the second allowable deviation limit selection criterion, a selection criterion (in this case, a third) is applied (i.e., a selection criterion based on the maximum allowable segment length), according to which, such as Figure 8 As shown, the length L21 of each line segment 21 with two consecutive points selected as ends is calculated, and if the calculated length L21 exceeds the predefined maximum allowable length value Lmax, then one of the potential guide points PGk that lies strictly between the two points forming the ends of the considered line segment 21 is added to the list of selected points, as shown. Figure 8 As shown.

[0103] exist Figure 8 In the example, the two line segments 21 that initially exceeded the maximum allowed length Lmax were the segment connecting PG6 and PG12 and the segment connecting PG22 and PG29. This resulted in PG11 and PG27 being added to the selection results respectively.

[0104] Preferably, according to the third selection criterion based on the maximum permissible segment length, the added point is the potential guide point PGk that forms the maximum segment with a length less than or equal to the maximum permissible length value Lmax with the potential guide point PGk forming the starting end of the considered segment 21, such as... Figure 8 As shown, or as a variation, it is the potential leading point PGk that is closest to the middle of the line segment 21 under consideration.

[0105] Here, of course, the third length limit standard can be repeated multiple times as needed to achieve a path in which all line segments meet the third standard, that is, all line segments have a length less than or equal to the maximum allowed length Lmax.

[0106] Limiting the maximum permissible length of the line segment (i.e., the “free fall” value of the laying head 1) prevents the laying head 1 from blindly traveling too far, and thus in particular prevents the risk or consequences of the actual path of the laying head 1 possibly exceeding or drifting relative to the path specified by the line segment in the path table (more generally, relative to profile 10).

[0107] The maximum allowed length value Lmax can be set to a distance, or alternatively, in a substantially equivalent manner, to the maximum allowed number of unselected potential guide points that exist between the two selected points, that is, the extent of the space of the "empty" grid between the two selected points.

[0108] As an indication, the maximum permissible length Lmax can be selected between 10mm and 50mm.

[0109] Preferably, in the simplification step (d), more preferably, after applying the various selection criteria described above, a selection criterion (in this case, the fourth) is applied, namely, a quality-level-based selection criterion, according to which N potential guide points immediately preceding each of the selected points and N potential guide points immediately following each of the selected points are added to the selected points, where N is an integer, preferably zero by default, and its value is set by the user.

[0110] Preferably, the value of N will be adjusted based on experience and more specifically increased, for example, to a value of 1 or 2, preferably based on testing the tires manufactured using a simplified path table obtained after applying one or more previous criteria (in this case, the first, second, and third selection criteria), subsequently evaluating the quality of the obtained tires, and if the quality is deemed insufficient, increasing the value of N by one unit.

[0111] Advantageously, this quality-level-based selection criterion will be able to improve the quality of finishing, particularly the appearance of the tire and the connection quality between continuous rims, especially in the portion of profile 30 affected by directional changes (bending).

[0112] Specifically, if N=1, such as Figure 9 As shown in the example, any potential guide point PGk adjacent to the previously selected point (using one of the first, second, and third selection criteria mentioned above) is added to the path table.

[0113] In this case, this would be equivalent to adding potential guide points PG2, PG4, PG7, PG10, PG14, PG16, PG18, PG20, PG23, PG26, and PG28 to the selection results.

[0114] Subsequently, all unselected points are deleted after applying one or more selection criteria. Specifically, at least all unselected potential guide points PGk are deleted, and preferably, unselected potential guide points PGk, as well as unselected geometric salient points PPi and functional salient points PFj, are deleted.

[0115] Ultimately, this results in simplified path table 20, as follows: Figure 10 As shown, only a portion of the salient points PPi and PFj are retained. Most importantly, all potential guide points PGk are retained. More specifically, in this case, on the one hand, only the first and last functionally salient points PF1 and PFm = PF3 are retained, and on the other hand, a portion of the potential guide points (such as those identified by applying the first, second, third, and fourth selection criteria in the order described above) are retained as final path points.

[0116] exist Figures 3 to 10 In the example, in addition to the functionally significant points PF1=Pstart and PF3=Pend, the following series of potential guide points will therefore be preserved: PG1 (consistent with PF1 by definition) to PG2, PG4 to PG7, PG10 to PG14, PG16 to PG18, PG20 to PG23, and PG26 to PG29, which immediately precede PF3.

[0117] The "gaps" that separate the series of points from each other constitute a simplification of the path table.

[0118] As a guideline, it should be noted that the final number of path points selected (and thus the total number of path points stored in the simplified path table 20 as rows of a table) is preferably between 150 (one hundred and fifty) points and 1000 (one thousand) points.

[0119] In any case, the reduction ratio (which is equal to the ratio between the size of the simplified path table 20 obtained after applying the selection criteria and the size of the "original" path table produced by the meshing step (c)), that is, the ratio between the number of path points finally selected and thus included in the simplified path table 20 and the potential maximum number of path points represented by the sum of all salient points PPi, PFj and all potential guide points PGk initially available at the end of the original meshing step (c), is preferably substantially between 1 / 10 and 1 / 30, i.e., a factor that reduces the size of the path table by 10, 20 or even 30.

[0120] Therefore, the method according to the invention simplifies the servo control of the laying head 1 in a particularly effective manner, while maintaining excellent control of the laying path.

[0121] Of course, the present invention relates to a method for manufacturing tires, in which a simplified path table 20 is established according to any of the above possible path definition methods, and the simplified path table 20 is sent to a robotic arm 5 carrying a laying head 1, such that the robotic arm 5 executes the simplified path table 20 by using continuous line segments connecting selected continuous points stored in the simplified path table 20 as set points.

[0122] Preferably, the simplified path table 20 associates each selected point with the absolute rotation angle of the core 4, measures the absolute rotation angle of the core 4 as it rotates from a predefined origin during its rotation around its central axis X4, and assigns the position of the laying head 1 to the rotation angle of the core by the robotic arm 5.

[0123] For this purpose, the simplified path table 20 can be advantageously presented in tabular form, which includes points stored in rows, and whose input values ​​(typically values ​​stored in the first column of each row) will indicate the rotation angle corresponding to the point under consideration.

[0124] The angular position of the core can be encoded by any suitable sensor associated with the central axis X4, such as a resolver-type encoder.

[0125] Each row will preferably include the target coordinates (X, Y, Z) of the laying head 1 represented on each of the three axes (X5, Y5, Z5) of the Cartesian reference system attached to the base 6 of the robotic arm 5, and, where applicable, the angular directions (W, P, R) of the yaw, tilt, and possible pitch of the laying head 1 in the reference system.

[0126] As is customary, "tilt" will allow the laying head to tilt laterally (in this case, around an axis Y4 that coincides with axis Y5), thus tangent to the curvature of profile 10, such that this curvature is drawn in a meridional plane containing the central axis X4 and passes through the contact point between the laying head 1 and the receiving surface 4A of the core 4, while "yaw" will correspond to a rotation at the contact point between the laying head 1 and the receiving surface 4A about an axis perpendicular to the receiving surface 4A (in this case, radial, more specifically, vertical), and will enable the orientation of the tire assembly 2 such that the longitudinal direction of the tire assembly 2 is aligned with the direction in which the required helix angle of winding is formed relative to the circumference of the core 4.

[0127] Therefore, the following operations can be performed, for example:

[0128] The control unit creates a simplified path table 20 according to the path definition method described above, and then sends the simplified path table 20 to the robotic arm 5, requesting the robotic arm 5 to perform the following of points contained in the simplified path table 20. It should be noted that, as mentioned above, the robotic arm 5 possesses basic intelligence, that is, its own computing and data storage devices (existing but limited), which allows it to perform the following of set points from one point to the next, provided in the form of a path table, in the form of linear line segments.

[0129] Once the control unit calculates the angular position that core 4 must reach in order to begin the laying operation, that is, the angular position corresponding to the starting point Pstart of the first functional area, the control unit begins to rotate core 4.

[0130] At a predetermined refresh rate, robotic arm 5 uses an encoder to read the angular position of core 4.

[0131] Based on feedback on the angular position of core 4, robotic arm 5 searches for its row in simplified path table 20, and thus searches for the setpoint coordinates applicable at the time under consideration.

[0132] Once the row is identified, the robotic arm 5 reads the coordinates X, Y, Z, W, P, and R corresponding to its actual position (more specifically, the actual position and orientation of the laying head 1) in its own reference frame (X5, Y5, Z5).

[0133] Subsequently, the robotic arm 5 determines the distance it must travel (linear on the positioning axes X5, Y5, Z5, and angular for tilt, yaw, or pitch orientation rotation) to reach the coordinates X, Y, Z, W, P, and R given in the simplified path table by comparing the setpoint coordinates provided by the rows of the simplified path table with its own actual position coordinates.

[0134] Subsequently, the robotic arm 5 performs linear motion to reach the set point coordinates, that is, to reach the path point specified in the simplified path table, and thus place the laying head 1 in the desired configuration.

[0135] The cycle begins again until core 4 reaches the calculated final angular position, that is, the arrival point of the laying path, Pend, at the end of the last functional area, and robotic arm 5 thus reaches the last point (in this case, the last row) in its simplified path table 20.

[0136] Furthermore, according to its preferred features which in itself constitute the invention, the manufacturing method may preferably include a calibration step before executing the simplified path table 20 (and more generally before executing any path table), in which the positions of three target points on the core frame 7 are measured using a laser velocimeter mounted on a stage located at a selected reference position, so as to identify a first Cartesian reference system (X4, Y4, Z4) attached to the core frame relative to the position of the laser velocimeter stage, the stage being separated from the frame 7, referred to as the "core frame" 7, which carries the core 4 and the means for rotating the core 4, and is also separated from the base 6 of the robotic arm 5, subsequently placing targets such as cubes... The robotic arm 5, fixed in position (in this case, the wrist) to receive the laying head 1, then moves in a manner that continuously positions the target at three different points in space, and each time measures the position of the target to identify a second Cartesian reference frame (X5, Y5, Z5) attached to the robotic arm 5 (more specifically, the fixed base 6 of the robotic arm 5) relative to the same position of the laser velocimeter station, called the "robot reference frame". The robotic arm 5 is calibrated by superimposing the robot reference frame (X5, Y5, Z5) with the core reference frame (X4, Y4, Z4), thus aligning the orthogonal axes of the reference frames: X4 and X5, Y4 and Y5, Z4 and Z5.

[0137] Of course, the present invention is not limited to the above-described variant embodiments. Those skilled in the art can specifically separate or freely combine the above features, or replace the above features with equivalent solutions.

Claims

1. A method for controlling a laying head (1) for laying at least one tire assembly (2) by looping a tire assembly (2) around a receiving surface (4A) of a core (4) rotating about a central axis (X4), the receiving surface (4A) having a predetermined profile (10) along the central axis, the method comprising: - Step (a) of geometric representation of the contour, in which the contour line of the contour (10) of the receiving surface (4A) is provided, and a first set of salient points called "geometric salient points" (PP1, PP2..., PPi..., PPn-1, PPn) are separated on the contour. These points are considered to be features of the shape of the contour (10), and the geometric salient points (PP1, PP2..., PPi..., PPn-1, PPn) are stored in the form of a set of path points called a "path table". - Step (b) of the functional characterization of the profile, in which multiple functional zones are defined on the profile, each extending from a region start point to a region end point, and a paving pattern is associated with each of the functional zones, the paving pattern specifying the conditions for paving the tire assembly in the considered functional zones, and the region start point and the region end point forming a second set of salient points called "functional salient points" (PF1, PF2..., PFj..., PFm-1, PFm) are inserted into the path table. - The next step is the meshing step (c), in which, referring to the predetermined travel direction (FWD) of the contour, a series of equidistant virtual points called "potential guide points" are defined on the contour (10) from the first functional salient point (PF1), i.e., the point starting from the first functional area which is considered the origin, to the last functional salient point (PFm), i.e., the point ending at the last functional area. The potential guide points are paired to delineate all line segments with the same length, which is equal to a predetermined selection value called "unit resolution spacing" (P_unit), and the potential guide points are inserted into the path table. - This is followed by a simplification step (d), in which at least a portion and only a portion of the potential guide points and geometrically and functionally significant points contained in the path table are selected by applying one or more selection criteria to the path table, and the size of the path table is reduced by deleting unselected points to obtain a reduced-size simplified path table (20), in which the length of at least one line segment connecting pairs of consecutively selected points is strictly greater than the selected unit resolution spacing (P_unit).

2. The method according to claim 1, characterized in that, In the simplification step (d), a reduced-size simplified path table (20) is obtained by applying one or more selection criteria to the path table to select at least a portion and only a portion of the potential guide points and geometrically or functionally significant points contained in the path table, and by deleting unselected points. In this reduced-size path table, the length of several line segments connecting consecutively selected pairs of points is strictly greater than the selected unit resolution spacing (P_unit).

3. The method according to claim 1, characterized in that, In the simplified step (d), a selection criterion is applied based on surrounding the selected point. According to the selection criterion, a first functional salient point (PF1) is selected as the starting point (Pstart) of the paving path, and a last functional salient point (PFm) is selected as the ending point (Pend) of the paving path. For at least one geometric or functional salient point that is strictly between the starting point (Pstart) and the ending point (Pend), at least one of the two potential guide points surrounding the geometric or functional salient point is selected, i.e., the potential guide point immediately before the geometric or functional salient point and the potential guide point immediately after the geometric or functional salient point.

4. The method according to claim 1, characterized in that, In the simplified step (d), a selection criterion is applied based on surrounding the point, and a first functional salient point (PF1) is selected according to the selection criterion as the starting point (Pstart) of the paving path, and a last functional salient point (PFm) is selected as the destination point (Pend) of the paving path. For each geometric or functional salient point that is strictly between the starting point (Pstart) and the destination point (Pend), at least one of the two potential guide points surrounding the geometric or functional salient point is selected, i.e., the potential guide point immediately before the geometric or functional salient point and the potential guide point immediately after the geometric or functional salient point.

5. The method according to claim 3, characterized in that, For at least one geometric or functional salient point exactly between the starting point (Pstart) and the destination point (Pend), or correspondingly for each geometric or functional salient point exactly between the starting point (Pstart) and the destination point (Pend), select each of two potential guide points surrounding the geometric or functional salient point, i.e., one immediately before the geometric or functional salient point and the other immediately after the geometric or functional salient point.

6. The method according to any one of claims 3 to 5, characterized in that, After selecting one or more potential guide points around a geometrically or functionally significant point that lies strictly between the start point (Pstart) and the end point (Pend) based on the selection criteria, the considered geometrically and functionally significant points are deleted.

7. The method according to claim 1, characterized in that, In the simplified step (d), a selection criterion based on the allowable deviation limit is applied. According to the selection criterion, for each pair of adjacent line segments defined by every three selected consecutive points, the interpolation circle (Ck) passing through three of the three points is considered, and for each of the two line segments (21) defined by two consecutive points, the deflection (D) between the line segment (21) forming the arc chord and the arc (22) of the interpolation circle corresponding to the line segment (21) is calculated, and if the deflection (D) calculated for the line segment (21) exceeds the predefined maximum allowable deviation value (Dmax), then one of the intermediate potential guide points or the intermediate potential guide points located between the potential guide points forming the ends of the considered line segment (21) is added to the list of selected points.

8. The method according to claim 1, characterized in that, In the simplified step (d), a selection criterion based on the allowable deviation limit is applied. According to the selection criterion, for each pair of adjacent line segments defined by every three selected consecutive points, the interpolation circle (Ck) passing through three of the three points is considered, and for each of the two line segments (21) defined by two consecutive points, the deflection (D) between the line segment (21) forming the arc chord and the arc (22) of the interpolation circle corresponding to the line segment (21) is calculated, and if the deflection (D) calculated for the line segment (21) exceeds the predefined maximum allowable deviation value (Dmax), the potential guide point closest to the middle of the considered line segment (21) is added to the list of selected points.

9. The method according to claim 1, characterized in that, In the simplified step (d), a selection criterion based on the maximum allowable segment length is applied. According to the selection criterion, the length (L21) of each segment (21) with two consecutive points selected as ends is calculated. If the calculated length (L21) exceeds the predefined maximum allowable length value (Lmax), one of the potential guide points that is strictly between the two points forming the end of the considered segment (21) or the potential guide point that is closest to the middle of the considered segment (21) is added to the list of selected points.

10. The method according to claim 1, characterized in that, In the simplified step (d), a selection criterion based on the maximum allowable segment length is applied. According to the selection criterion, the length (L21) of each segment (21) with two consecutive points selected as ends is calculated. If the calculated length (L21) exceeds the predefined maximum allowable length value (Lmax), the potential guide point of the largest segment with a length less than or equal to the maximum allowable length value (Lmax) formed with the potential guide point forming the starting end of the considered segment, or the potential guide point closest to the middle of the considered segment (21), is added to the list of selected points.

11. The method according to claim 1, characterized in that, In the simplified step (d), a quality-level-based selection criterion is applied, according to which N potential guide points immediately preceding each of the selected points and N potential guide points immediately following each of the selected points are added to the selected points. N is an integer, and the value of N is set by the user.

12. The method according to claim 11, characterized in that, N defaults to zero.

13. The method according to claim 11 or 12, characterized in that, The value of N is adjusted based on experience, and more specifically increased to a value of 1 or 2.

14. The method according to claim 13, characterized in that, The quality of the tires is evaluated based on tests conducted using a simplified path table obtained after applying one or more previous criteria, and if the quality is deemed insufficient, the value N is increased by one unit.

15. The method according to claim 1, characterized in that, The unit resolution spacing (P_unit) of the potential guide points generated in the meshing step (c) is separated in pairs between 0.1 mm and 1 mm.

16. The method according to claim 1, characterized in that, The unit resolution spacing (P_unit) of the potential guide points generated in the meshing step (c) is separated in pairs and is equal to 0.5 mm.

17. The method according to claim 1, characterized in that, In step (b) of the functional characterization of the profile, the laying pattern is associated with each functional area, which characterizes the conditions for laying the tire assembly (2) in the functional area under consideration by specifying at least one laying parameter with a value that is applicable and constant in the area under consideration: (i) the nature of the tire assembly, (ii) the laying spacing, the offset of the laying head (1) relative to the core (4) along the central axis (X4) between two consecutive turns according to the laying spacing, (iii) the laying speed, which corresponds to the circumferential speed of the core (4) on which the tire assembly (2) is wound, and / or (iv) the laying tension, which corresponds to the longitudinal tension applied in the tire assembly (2) under the traction of the rotating core (4) during laying.

18. The method according to claim 1, characterized in that, In step (b) of the functional characterization of the profile, the laying pattern is associated with each functional area, which characterizes the conditions for laying the tire assembly (2) in the functional area under consideration by specifying several laying parameters applicable and constant in the area under consideration from the following parameters: (i) the nature of the tire assembly, (ii) the laying spacing, the offset of the laying head (1) relative to the core (4) along the central axis (X4) between two consecutive turns according to the laying spacing, (iii) the laying speed, which corresponds to the circumferential speed of the core (4) on which the tire assembly (2) is wound, and / or (iv) the laying tension, which corresponds to the longitudinal tension applied in the tire assembly (2) under the traction of the rotating core (4) during laying.

19. The method according to claim 3 or 4, characterized in that, Selecting at least one of the two potential guide points includes selecting the one that is closest to the geometrically or functionally significant point under consideration.

20. A method for manufacturing a tire, wherein a simplified path table (20) is established based on the method for controlling a laying head according to any one of claims 1 to 19, and the simplified path table (20) is sent to a robotic arm (5) carrying a laying head (1), such that the robotic arm (5) executes the simplified path table (20) using a series of line segments connecting consecutive selected points stored in the simplified path table as set points.

21. The method for manufacturing a tire according to claim 20, characterized in that, The simplified path table (20) associates each selected point with the absolute rotation angle of the core, measures the absolute rotation angle of the core as it rotates from a predefined origin during the rotation of the core (4) around the central axis (X4), and assigns the position of the laying head (1) to the core's rotation angle by the robotic arm (5).

22. The method of manufacturing a tire according to claim 20 or 21, characterized in that, The method includes a calibration step in which the positions of three target points on the core frame are measured using a laser velocimeter mounted on a stage at a selected reference position, so as to identify a first Cartesian reference system (X4, Y4, Z4) attached to the core frame (7) relative to the position of the laser velocimeter stage, the stage being separated from the frame (7) called the "core reference system" and the means for rotating the core, and from the base (6) of the robotic arm (5), after which a target such as a cube is fixed to the robotic arm (1) designed to receive the laying head (1). The position of the target is determined by the robotic arm (5) moving in a manner that continuously positions the target at three different points in space, and each time the position of the target is measured in order to identify a second Cartesian reference frame (X5, Y5, Z5) attached to the robotic arm (5) relative to the same position of the laser velocimeter platform. The robotic arm (5) is calibrated by superimposing the robotic reference frame (X5, Y5, Z5) with the core reference frame (X4, Y4, Z4), thus aligning the orthogonal axes of the robotic reference frame (X5, Y5, Z5) and the core reference frame (X4, Y4, Z4).

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