Installation and process for manufacturing tire blanks

Abstract

A tire blank manufacturing installation (10) comprising a rotating mobile tire blank manufacturing drum (16), a platform (21) disposed upstream of the drum (16) and comprising a flat surface (21a) for receiving one end of an elastomeric element, at least one robotic arm (18) configured to grasp the end portion of the elastomeric element from above and comprising at least three rows of magnetic material elements and a UCE (40) configured to drive the robotic arm (18), and at least one first 3D camera configured to acquire an image of the end portion of the elastomeric element on the platform (21). The ECU (40) comprises at least one module (50) for gripping the end portion of the elastomeric element based on the point cloud reconstructed by the first camera and an anchoring module for said end on the external surface (16a) of the drum (16). Figure for the abbreviation: Fig 1

Description

Title of the invention: Installation and method for manufacturing tire blanks

[0001] The present invention relates to the field of manufacturing a tire and more particularly relates to a method of manufacturing tire blanks and an installation allowing the implementation of such a method.

[0002] A tire of a wheel of a motor vehicle generally comprises three distinct zones comprising a crown which has a crown reinforcement and a tread intended to come into contact with the ground, beads intended to ensure the fixing of the tire on a rim of a wheel and sidewalls intended to connect the crown to the bead.

[0003] The tire further comprises a metal or textile fiber structure forming a reinforcing carcass for the tire structure and making it possible to connect the crown to the beads.

[0004] To manufacture a tire blank, elements in the form of bead wires, strips or plies are successively assembled so as to form a cylindrical carcass reinforcement. The cylindrical carcass reinforcement is then transformed into a toroidal carcass reinforcement, during a step known as "shaping". During this step, the crown of the cylindrical carcass reinforcement is stretched so as to increase the diameter and the beads are axially brought together. Finally, elements in the form of strips or plies are successively assembled on the crown of the carcass reinforcement so as to additionally form a crown reinforcement and a tread.

[0005] The assembly and shaping steps are generally carried out on a cylindrical tire blank manufacturing drum, which can rotate about an axis of symmetry of revolution. The elements in the form of wires, strips or plies are placed circumferentially on the drum or on the tire blank being manufactured. The installation steps are carried out manually or automatically.

[0006] When the laying steps are carried out manually, an operator located in front of the drum grasps the end part of an element, for example, a ply wound on a reel, pulls it to the drum, positions it and secures it on the drum or the tire blank being manufactured. The drum is then rotated so as to complete a complete revolution. During the rotation of the drum, the operator guides the ply so that the winding of the ply forms a slanted probably a straight cylinder. The operator then cuts the sheet, and adjusts the junction between the two ends of the sheet.

[0007] However, performing the installation step manually has many disadvantages. The operator is limited in speed and precision. Approaching or exceeding these limits also leads to an increase in the difficulty of the operator's work and their cognitive load, which can lead to a reduction in the quality of the tire blanks manufactured, or even in the operator's safety.

[0008] Furthermore, the automation of the laying steps as carried out manually presents technical difficulties, in particular the design of a manufacturing machine capable of implementing said laying steps and, above all, the programming of said machine so that it is able to execute said laying steps.

[0009] Machines for manufacturing tire blanks are known in which a drum is movable by means of a carriage or a robotic arm between several installation stations. Each installation station is adapted to install a particular element such as a bead or a strip. Since the rate of each station is not identical, the fastest installation stations are not fully utilized, which penalizes their efficiency. In addition, the design, manufacture and operation of such an assembly machine are very complex and expensive.

[0010] Machines for manufacturing tire blanks are also known which have only two installation stations, each station being adapted to install a set of pre-assembled elements. Thus, two complete revolutions of the drum are sufficient to install a first assembly intended to constitute a carcass reinforcement and a second assembly intended to constitute a crown reinforcement and a tread. However, such a manufacturing machine requires that the architecture and composition of the tire blank themselves be adapted, which considerably constrains the process of designing and industrializing the tire.

[0011] Document FR - Bl- 3 116 227 is also known, which proposes the automatic placement of an elastomeric element on a drum for manufacturing blanks comprising a determined sequence of steps for gripping and pulling the elastomeric element towards the drum using a robotic arm comprising an effector. However, this document proposes a collaborative robotic arm, i.e. in collaboration with an operator who manually carries out a step of a step of the sequence after an interruption step.

[0012] Furthermore, this document does not describe how the installation step is carried out.

[0013] Indeed, the mechanical reinforcement of an elastomeric element coupled with the fact that said element is wound around a reel generates an end surface which is not completely flat once unrolled in order to be placed on the ex surface inner side of the drum. In addition, the stiffness of the element can influence its transverse position of its unrolled end on a flat surface. In other words, the transverse position of the tip of the unrolled elastomeric element can be angularly offset from an axial axis perpendicular to the axis of rotation of the drum.

[0014] Thus, there is a need to remedy the aforementioned drawbacks and to automate tire blank manufacturing machines while improving the installation of the elastomeric element and maintaining satisfactory reliability and productivity.

[0015] The invention aims to improve the installation of the elastomeric element, and in particular the gripping of the elastomeric elevation upstream of the drum and the anchoring of said elastomeric element on said drum.

[0016] The invention also aims to improve the cutting of the elastomeric element.

[0017] The present invention relates to an installation for manufacturing tire blanks associated with a first orthogonal reference mark and comprising a drum for manufacturing tire blanks movable in rotation about an axis of rotation of the first reference mark, a platform arranged upstream of the drum, extending along a transverse axis of the first reference mark and comprising a flat surface for receiving an end portion of an elastomeric element or ply, at least one robotic arm and an electronic control unit, acronym UCE, configured to control the robotic arm.

[0018] The installation further comprises at least one first three-dimensional camera restoring a cloud of points of coordinates measured in a reference frame associated with said first camera and having a line of sight oriented towards the platform and configured to acquire an image of the end portion of the elastomeric element on the platform.

[0019] The robotic arm comprises at least one gripper associated with a second orthogonal reference mark distinct from the first reference mark and configured to grip the end portion of the elastomeric element from above.

[0020] Said gripper comprises at least three rows of elements made of magnetic material or magnets parallel to each other and regularly spaced from one another along an extension axis of the second reference mark.

[0021] The UCE includes at least: - a gripping module for the end part of the elastomeric element configured to determine a gripping point of the gripper as a function of the point cloud restored by the first camera, and - a module for anchoring said end portion on the external surface of the drum configured to determine an anchoring point for each of the rows of elements in magnetic material on the outer surface of the drum.

[0022] Consequently, the assembly installation is agile unlike the multi-station automatic assembly machines of the state of the art for which each station is dedicated to the installation of a particular pre-assembled element or assembly.

[0023] In addition, the robotic arm is more precise than an operator, while being faster, which allows the improvement of the quality of the manufactured tire blanks, and the increase in the operating time of the manufacturing facility. Useful time means the net time without taking into account the time related to the manufacture of tire blanks that are not satisfactory in terms of quality. Net time means the time during which the machine manufactures tire blanks, without taking into account the time related to rate deviations and failures.

[0024] The tip of the elastomeric element or sheet corresponds to the end of the end portion, for example triangular, of the elastomeric element. In other words, the tip corresponds to the summit or peak of said end portion.

[0025] For example, said end portion extends along the extension axis of the second reference mark angularly offset from the transverse axis of the first reference mark.

[0026] The angular offset angle between the extension axis of the second reference mark and the transverse axis of the first reference mark is preferably non-zero.

[0027] Advantageously, the gripping module comprises: - a module for acquiring the image of the end part of the elastomeric element on the platform by the first camera, - a module for cutting the image of the end part of the elastomeric element on the platform into three zones, and - a module for determining the position of the gripper and in particular the gripping point comprising a first image processing processor configured to determine an initial gripping point in the point cloud of the image from the acquisition module and to correct said initial gripping point by translation of said initial gripping point by a distance corresponding to the radius of the magnets of the gripper along the extension axis of the second reference frame and along a second longitudinal axis of the second reference frame perpendicular to said extension axis and to determine the gripping point transmitted to the robotic arm by a transmission module.

[0028] Such a translation makes it possible to increase the magnetization surface of the gripper with the end part of the elastomeric element.

[0029] The three zones of the end portion visible on the platform include a first zone corresponding to the zone located between the tip or peak of the end portion and a second zone, the second zone is located between the first zone and a third zone and the third zone is located between the second zone and the edge of the platform.

[0030] The total length of the end portion of the elastomeric element corresponds to the distance between the tip of said end portion and the edge of the platform.

[0031] Preferably, the first and third zones each correspond to 30% of the total length. Alternatively, the length of the first zone could be different from the length of the third zone. For example, the length of the first zone could be between 20% and 30% of the total length and the length of the third zone could be between 20% and 30% of the total length.

[0032] According to one embodiment, the module for determining the position of the gripper is configured to determine a straight line passing through the lateral side of the second zone, the gripping point being axially offset from the tip of the end portion by a distance.

[0033] According to one embodiment, the installation comprises a first fixed vertical laser indicating the center of the drum, a second fixed horizontal laser indicating the laying azimuth of the elastomeric element and two variable vertical lateral lasers indicating the laying longitude, said lasers being integral with a fixed structure or gantry of the installation. The anchoring module comprises a module for projecting said lasers onto the external surface of the drum, and in particular onto a laying zone of the end of the elastomeric element.

[0034] For example, the installation comprises a second three-dimensional camera restoring a cloud of points of coordinates measured in a reference frame associated with said second camera and having a line of sight oriented towards the drum and configured to acquire an image of a laying zone on the external surface of the drum.

[0035] The anchoring module comprises: - a module for acquiring an image of said installation area taken by said second camera, and - a module for processing the image of said laying area configured to detect the lasers and an intersection pixel at the intersection between the second horizontal laser and one of the lateral lasers, namely the right lateral laser if the end part of the elastomeric element is oriented to the right or the left lateral laser if the end part is oriented to the left and a middle pixel at the intersection of the first horizontal vertical laser and the second horizontal laser to estimate an intersection point and a middle point corresponding to the three-dimensional points of the intersection pixels and the middle of the drum.

[0036] Advantageously, the anchoring module comprises: - a module configured to determine the anchor point of each of the magnets relative to the intersection point in a normal plane where there is a circle fitted in the point cloud of one of the lateral lasers and as a function of a distance between two rows of magnets as well as the radius of a magnet, - a module for transmitting said anchoring points to a control module of the gripper, said control module being configured to separately control the rows of magnets of the gripper, and in particular the actuators of each magnet.

[0037] For example, the ECU comprises a module for clamping the elastomeric element around the drum, a module for cutting the elastomeric element to the desired length and a module for welding the cut part of the elastomeric element with the end part anchored on the external surface of the drum.

[0038] According to one embodiment, the gripper of the robotic arm comprises actuators each connected to a magnet, said actuators being controlled separately to successively release the third row of magnets, the second row of magnets and then the first row of magnets.

[0039] When anchoring the end portion of the elastomeric element to the drum, it is preferable that the actuators are deactivated row by row to release the anchored areas of the elastomeric element.

[0040] The anchoring module makes it possible to anchor a product of complex shape on a rounded shape, i.e. the drum, by determining three anchoring points belonging to the same circle.

[0041] The magnetic material elements of the gripper of the robotic arm are preferably mounted on a support configured to be connected to the end portion of the robotic arm(s) in the case where there are two robotic arms.

[0042] According to one embodiment, the first, second and third rows of elements made of magnetic material each comprise at least one element made of magnetic material.

[0043] According to another embodiment, the first and second rows of magnetic material elements of the gripper of the robotic arm each comprise a single magnetic material element.

[0044] For example, the third row comprises at least three magnetic material elements or magnets, one of the magnetic material elements of the third row being aligned along the extension axis with the magnetic elements of the first and second rows.

[0045] For example, the set of magnetic elements is arranged to form a T.

[0046] Generally, the shape of the gripper is symmetrical.

[0047] Due to the symmetrical arrangement of the gripper, it is possible to use the same gripper to grip the end portion of a right-facing elastomeric element or the end portion of a left-facing elastomeric element.

[0048] Alternatively, it could be provided that the gripper comprises a different number of elements made of magnetic material, for example greater than or equal to six.

[0049] The elements made of magnetic material may have a circular or rectangular section or any other section.

[0050] According to one embodiment, the installation comprises a second robotic arm. For the gripping and anchoring steps, only one robot arm is necessary. However, the presence of a second robotic arm makes it possible to grip the end portion of an elastomeric element oriented in the second direction. The second robotic arm is, moreover, used during the cutting step in order to hold the end portion against the drum.

[0051] For example, the first 3D camera, for example, an RGB-D sensor, is fixed, and directed upstream towards the platform and fixed on the fixed structure or gantry.

[0052] The first 3D camera is advantageously used in the installation and gripping steps.

[0053] The first 3D camera makes it possible to avoid the necessary recalibration when using a 2D camera. Indeed, the first 3D camera will immediately bring the distance of the object and its perceived size into coincidence, which makes it possible to measure the dimensions of the object without having to indicate the depth at which it is located in relation to the camera.

[0054] For example, the second 3D camera, for example an RGB-D sensor, is fixed and directed towards the drum, in particular fixed to the fixed structure or gantry.

[0055] The second 3D camera is advantageously used in the anchoring, cutting and welding steps.

[0056] The RGB-D type 3D camera is advantageously calibrated or calibrated only with respect to the robotic arm, and not with the environment since said camera detects the environment in three dimensions and can allow the measurement and determination of the positions and orientations of the elements located in its field of vision, which allows the platform to be oriented according to different orientations. In other words, it is the 3D camera which will adapt to the orientation of the platform.

[0057] In the case where there are two robotic arms, the two RGB-D type 3D cameras are advantageously calibrated or calibrated only with respect to the two robotic arms.

[0058] According to one embodiment, the platform comprises at least one plate or strip of magnetic or magnetized material extending along a longitudinal axis parallel to the axis of rotation and arranged on the receiving surface of the platform.

[0059] The magnetic strip makes it possible to attract the wires of the elastomeric element with magnetic properties and thus to press the end part of said element onto the platform. Alternatively, it could be provided that the platform does not include such a magnetic strip.

[0060] According to a second aspect, the invention relates to a method for automatically and successively laying elastomeric elements using a tire blank manufacturing installation associated with a first orthogonal reference frame and comprising a tire blank manufacturing drum movable in rotation about an axis, a platform arranged upstream of the drum, extending along a transverse axis of the first reference frame and comprising a flat surface for receiving one end of an elastomeric element, at least one robotic arm provided, and at least one first three-dimensional camera restoring a cloud of points of coordinates measured in a reference frame associated with said first camera and having a viewing axis oriented towards the platform and configured to acquire an image of the end portion of the elastomeric element on the platform, in particular on the flat receiving surface.

[0061] The robotic arm comprises at least one gripper associated with a second orthogonal reference mark distinct from the first reference mark and configured to grip the end portion of the elastomeric element from above.

[0062] Said gripper comprises at least three rows of elements made of magnetic material or magnets parallel to each other and regularly spaced from one another along an extension axis of the second reference mark.

[0063] The method comprises at least one laying step comprising a sequence comprising at least:

[0064] - a step of gripping the end part of the elastomeric element, during in which a gripping point of the gripper is determined based on the point cloud returned by the first camera; and

[0065] - a step of anchoring said end on the external surface of the drum, when which determines an anchoring point for each of the rows of elements in magnetic material on the external surface of the drum.

[0066] Thus, during the anchoring step, contact pressure is applied and the parts of the end part anchored to the drum are gradually released.

[0067] For example, said end portion extends along an extension axis of the second reference mark angularly offset from the transverse axis of the first reference mark.

[0068] Advantageously, the step of gripping the end portion of the elastomeric element comprises a step of acquiring the image of the end portion of the elastomeric element on the platform by the first camera, a step of cutting the image of the end portion of the elastomeric element on the platform into three zones, a step of determining the position of the gripper, in particular of an initial gripping point, in the point cloud of the image acquired in the acquisition step using a processing processor, a step of correcting the initial gripping point by translating the initial gripping point by a distance corresponding to the radius of each of the magnets of the gripper along the extension axis of the second reference mark and along a second longitudinal axis of the second reference mark perpendicular to said extension axis parallel to the rotation axis and the transverse axis to obtain the gripping point and a step of transmitting said gripping point to the robotic arm with a view to gripping the end part of the elastomeric element by the gripper.

[0069] Advantageously, the anchoring step comprises a step of projecting lasers and a step of acquiring an image of a laying surface on the external surface of the drum taken by a second camera, for example an R-GBD sensor, restoring a cloud of points of coordinates measured in a reference frame associated with said second camera and having a line of sight oriented towards the drum, said steps of projecting lasers and acquiring an image being carried out before the step of taking the end part of the elastomeric element by the gripper.

[0070] The lasers comprise a first fixed vertical laser indicating the center of the drum, a second fixed horizontal laser indicating the azimuth of installation of the elastomeric elements and two variable vertical lateral lasers indicating the installation longitude, in order to anticipate the trajectory of the robotic arm and to know where to anchor said end.

[0071] For example, the anchoring step further comprises:

[0072] - a step of processing the image of the laying area, during which the lasers and a point cloud restored by the second camera, we isolate the pixels associated with the lasers in the image acquired during the acquisition step and we detect the intersection pixel at the intersection between the second horizontal laser and one of the lateral lasers,

[0073] - a step determining the anchoring point of each of the rows of magnets by relative to the intersection point in a normal plane where there is a fitted circle in the point cloud of one of the side lasers and as a function of a distance between two rows of magnets as well as the radius of a magnet of the gripper, and - a step of transmitting the anchoring points of each of the magnets to a gripper control module configured to separately control the rows of magnets of the gripper and in particular the actuators of each magnet.

[0074] Advantageously, prior to the laying step, the method comprises a step of supplying the elastomeric element during which the end part of the elastomeric element is placed on the surface of a platform of the installation.

[0075] According to one embodiment, the sequence of the laying step further comprises a step of clamping the elastomeric element around the drum, a step of cutting the elastomeric element to the desired length and a step of welding the cut portion of the elastomeric element with the end portion anchored on the external surface of the drum.

[0076] Other aims, characteristics and advantages of the invention will appear on reading the following description, given solely by way of non-limiting example, and made with reference to the appended drawings in which:

[0077] [Fig.l] very schematically represents an overall view of an installation for manufacturing tire blanks implementing a method for manufacturing tire blanks according to the invention;

[0078] [Fig.2A], [Fig.2B], [Fig.2C] illustrate in detail the position of the end portion of the elastomeric element on the platform of the installation of [Fig.l];

[0079] [Fig.3A], [Fig.3B], [Fig.3C] illustrate different angular positions of the part end of the elastomeric element relative to the transverse axis;

[0080] [Fig.3D] represents a detail of [Fig.3B];

[0081] [Fig.4] partially illustrates the gripper of the installation of [Fig.l];

[0082] [Fig.5] illustrates the steps of image processing by the image processor of the installation of [Fig.l];

[0083] [Fig.6] schematically illustrates a three-dimensional representation from the first RGB-D camera;

[0084] [Fig.7] illustrates the translation of a gripping point of the end portion of the elastomeric element of the radius of a magnet of a gripper;

[0085] [Fig.8] schematically illustrates the image acquired of the external surface of the drum of the installation of [Fig.l] by the second camera;

[0086] [Fig.9] illustrates the position of the anchor points Pb P2, P3 of each of the magnets of the gripper relative to the intersection point P^ans a plane Pi (ji) of normal;

[0087] [Fig.10A] illustrates the fitted circle in the laser point cloud;

[0088] [Fig.lOB] illustrates the anchoring points of the magnets of the gripper;

[0089] [Fig. 11] illustrates an example of a pneumatic diagram for controlling the actuators of the magnets of the gripper;

[0090] [Fig.l2A], [Fig.l2B] illustrates the elastomeric element wrapped around the drum on a 360° revolution;

[0091] [Fig. 13A], [Fig.l3B], [Fig.l3C], [Fig.l3D] represent the successive stages of cutting of the elastomeric element;

[0092] [Fig. 14A] illustrates the exit point Ps of the cut when the elastomeric element is cut and its surface rolled on that of the drum;

[0093] [Fig. 14B] represents the position of the elastomeric element at the end of the anchoring of the end part of the elastomeric element on the drum;

[0094] [Fig. 14C] illustrates a region of interest ROI in which the incision point is brought during cutting;

[0095] [Fig. 15A], schematically shows the initial point of interest P^, and the final point of interest PFji;

[0096] [Fig.l5B] is a detail of [Fig.l5A];

[0097] [Fig.l5C] shows the angle of rotation q> to effect the locking of the elastomeric element;

[0098] [Fig. 16] is a flowchart illustrating certain steps of the method of manufacturing tire blanks according to the invention.

[0099] In the remainder of the description, we consider a first reference frame or orthonormal base X, Y, Z, associated with the installation 10 for manufacturing tire blanks in which we find:

[0100] - a longitudinal axis X, horizontal and extending from back to front on [Fig.l] and parallel to the axis of rotation X-X' of the drum 16;

[0101] - a transverse axis Y, horizontal, perpendicular to the longitudinal axis X and extending from left to right on [Fig.l]; and

[0102] - a vertical axis Z, orthogonal to the longitudinal axes X and transverse Y and extending from bottom to top on [Fig.l].

[0103] We also consider a second reference frame or orthonormal base X, Y, Z, associated with the tool, in particular with the gripper 25 used, in which we find:

[0104] - a longitudinal axis XI, horizontal and extending from left to right on [Fig.7];

[0105] - an extension axis Yl, horizontal, perpendicular to the longitudinal axis XI of the gripping mark and extending from bottom to top on [Fig.7]; and

[0106] - a vertical axis Zl, orthogonal to the longitudinal axes X and extension Yl and extending from back to front on [Fig.7], said vertical axis Zl being coincident with the vertical axis Z of the reference associated with the installation.

[0107] [Fig.l] illustrates an installation 10 for manufacturing tire blanks comprising a station 12 for supplying elastomeric elements 13 and at least one station 14 for laying said elements.

[0108] By “elastomeric element” is meant an elastomeric product possibly reinforced, calendered or extruded according to a given profile so as to form a continuous strip or sheet and, by extension, a set of pre-assembled elastomeric elements. An elastomeric element 13 is here wound on a reel 15.

[0109] The installation station 14 comprises a drum 16 for manufacturing tire blanks (partially shown), a robotic arm 18 equipped with an effector 20 or tool adapted to the step of manufacturing the blank and a platform 21 for presenting the product.

[0110] By “laying station” we also mean the area in which the elastomers are laid.

[0111] As illustrated, and in a non-limiting manner, the supply station 12 for elastomeric elements 13 comprises a multi-axis industrial robot 34 capable of handling a container supporting an elastomeric element.

[0112] By "feeding station" is also meant the area in which the robot in industrial 34 is located. The feeding station 12 is adjacent to the laying station 14 and includes a storage space 36 in which the containers are arranged.

[0113] For example, the containers are in the form of reels 15, reels 38 comprising a reel 15 or roller tables supporting an elastomeric element unsuitable for being stored on a reel.

[0114] The manufacturing installation 10 comprises an electronic control unit 40, with the acronym UCE, configured to control the feeding station 12 and the laying station 14.

[0115] The ECU 40 is capable, in particular, of controlling the automatic installation of the elastomeric elements 13 on the drum 16.

[0116] The drum 16 has the shape of a cylinder, generally straight, with symmetry of revolution of central axis X-X'. The drum 16 is movable in rotation around the central axis X-X' relative to a support 24 fixed or movable in the horizontal plane by means, for example, of a carriage 23, or movable in several directions by means, for example, of a multi-axis industrial robot.

[0117] The radially external surface 16a of the drum 16 constitutes a laying surface with which the first laid element(s) 13 are in contact. The second laid element(s) are in contact with the radially external surface of the first laid element(s).

[0118] In a non-limiting manner, the robotic arm 18 may be of the six-axis type, and comprises a series of six parts of variable lengths, articulated together by six joints or pivots. For example, the robot comprises a base 18a mounted so as to pivot by a first joint (not visible) on a fixed structure or gantry 28, a first segment or shoulder 18b so as to pivot by a second joint 26 relative to the base 18a, a second segment or elbow 18c so as to pivot by a third joint 26a relative to the first segment 18b and a wrist 18d so as to pivot along three distinct axes of rotation relative to the second segment 18c by three joints (not visible). The base 18a and the wrist 18d can rotate on themselves. Each joint or pivot is actuated by an electric motor (not shown). The gripper(s) 20 is mounted integrally with the wrist 18d.Depending on the tools used and the layout of the installation station 14, the robotic arm 18 can take various forms with more or fewer axes of mobility.

[0119] The robotic arm 18 is configured to carry out the automatic and successive installation of an elastomeric element 13 on the drum 16.

[0120] For the gripping and anchoring steps, only one robot arm is required.

[0121] As explained below, the end portion 13a of the elastomeric element has a triangular shape oriented in one direction or another.

[0122] Thus, the installation could comprise a second robotic arm identical and parallel to the first robotic arm. The presence of a second robotic arm makes it possible to grasp the end portion 13a of an elastomeric element 13 oriented in the second direction. The second robot arm can, moreover, be used during the cutting step in order to hold the end portion against the drum.

[0123] Generally, the installation could comprise one or two robotic arms 18.

[0124] The tools 20 allowing the implementation of the automatic installation are chosen from the group comprising at least one gripper 25 and scissors. The gripper 25 will be described in detail with reference to FIGS. 4 and 7.

[0125] The tools 20 may also comprise rollers for applying pressure to the element once placed on the external surface 16a of the drum 16 and pressing it against said external surface 16a.

[0126] As illustrated, the installation 10 comprises a robotic arm 18 arranged overhanging relative to the drum 16, preferably more or less 0.5m from the central axis X-X' of the drum 16 in a horizontal direction.

[0127] As illustrated in detail in [Fig.2A], the product presentation platform 21 is arranged upstream of the drum 16 and upstream of a mechanical guide GM.

[0128] The platform 21 comprises a flat surface 21a for receiving one end 13a of the elastomeric element 13, and in particular the end portion 13a of said element 13 after partial unwinding of the reel 15.

[0129] The mechanical reinforcement of an elastomeric element 13 coupled with the fact that said element is wound around the reel 15 generates a surface of the end portion 13a which is not completely flat once unwound on the platform 21 in order to be placed on the external surface 16a of the drum 16, as can be seen in [Fig.2B].

[0130] The platform 21 may comprise, for this purpose, a plate or strip of magnetic or magnetized material element 21b extending along the longitudinal axis X and arranged on the surface 21a for receiving the elastomeric element 13. The magnet 21b makes it possible to attract the wires of the elastomeric element 13 with magnetic properties and thus to press the end part 13a of said element 13 onto the platform 21. Alternatively, it could be provided that the platform 21 does not comprise such a magnet 21b.

[0131] The rigidity of the elastomeric element 13 can influence its position of its unrolled end on the flat surface 21a of the platform 21. In other words, the longitudinal position of the end portion 13a of the unrolled elastomeric element 13 can extend along an extension axis Y1 which can be angularly offset relative to the transverse axis Y perpendicular to the axis X-X' of rotation of the drum 16.

[0132] [Fig.3A] illustrates the case where the end portion 13a of the elastomeric element 13 unrolled extends along an extension axis Y1 which is not angularly offset from the transverse axis Y perpendicular to the axis of rotation X-X' of the drum 16. This case is particularly rare.

[0133] [Fig.3B] illustrates the case where the end portion 13a of the unrolled elastomeric element 13 extends along an extension axis Y1 which is angularly offset inwardly relative to the transverse axis Y and [Fig.3C] illustrates the case where the end portion 13a of the unrolled elastomeric element 13 extends along an extension axis Yl which is angularly offset outwardly relative to the transverse axis Y.

[0134] The gripper 25, visible in detail in Figures 4 and 7, comprises three rows of elements made of magnetic material or magnets 25a, 25b, 25c, 25e, 25f parallel to each other and to the axis of rotation of the drum 16. The rows of elements made of magnetic material are regularly spaced from each other in the direction of extension Yl.

[0135] As illustrated, the first and second rows of magnetic material elements each comprise one magnetic material element 25a, 25b and the third row comprises three magnetic material elements 25c, 25e, 25f. One of the magnetic material elements 25c of the third row is aligned along the extension axis Yl' with the magnetic elements 25a, 25b of the first and second rows.

[0136] The set of magnetic elements 25a, 25b, 25c, 25e, 25f is here arranged so as to form a T. Generally speaking, the shape of the gripper is symmetrical.

[0137] By means of the T-shaped arrangement of the magnets or a symmetrical arrangement of the gripper, it is possible to use the same gripper to grip the end portion of a right-facing elastomeric element or the end portion of a left-facing elastomeric element.

[0138] Alternatively, it could be provided that the third row comprises only one element made of magnetic material.

[0139] As illustrated, the gripper 25 comprises five magnetic elements.

[0140] Alternatively, it could be provided that the gripper 25 comprises a different number of elements made of magnetic material, for example greater than or equal to six.

[0141] The magnetic material elements 25a, 25b, 25c, 25e, 25f are mounted on a support 25d configured to be connected to the end portion of one of the robotic arms 18.

[0142] The gripper 25 of the robotic arm 18 is configured to grip the end portion 13a of the elastomeric element 13 from above.

[0143] However, since the gripper 25 is rigid, it is not possible to align it with the end portion 13a of the elastomeric element 13 in the case where the latter extends along the extension axis Y1 angularly offset relative to the transverse axis Y as visible in [Fig.3B] or [Fig.3C].

[0144] The installation 10 comprises a first three-dimensional camera (not re presented), such as an RGB-D sensor, restoring a cloud of points of coordinates measured in a frame associated with said first camera and having a line of sight oriented towards the platform 21 and configured to acquire an image of the end part 13a of the elastomeric element 13 on the platform 21. This step corresponds to a step 151 of acquiring the image of the elastomeric element 13 on the platform 21. The first 3D camera is fixed to the gantry 28 and directed upstream towards the platform 21.

[0145] The first 3D camera makes it possible to avoid the necessary registration when using a 2D camera. Indeed, the first 3D camera will immediately bring the distance of the object and its perceived size into coincidence, which makes it possible to measure the dimensions of the object without having to indicate the depth at which it is located in relation to the camera.

[0146] The electronic control unit UCE 40 comprises for this purpose a module 50 for gripping the end part 13a of the elastomeric element 13.

[0147] The gripping module 50 comprises a module 51 for acquiring the image of the end portion 13a of the elastomeric element 13 on the platform 21 by the first 3D camera.

[0148] The gripping module 50 further comprises a module 52 for cutting the image of the end portion 13a of the elastomeric element 13 on the platform 21 into three zones Z1, Z2, Z3, visible in [Fig.3B].

[0149] The first zone Z1 corresponds to the zone located between the tip Ppo of the end part 13a, visible in [Fig.3D], and the second zone Z2, the second zone Z2 is located between the first and third zones Z1, Z3 and the third zone Z3 is located between the second zone Z2 and the edge 21c of the platform 21. The total length L of the end part 13a of the element 13 corresponds to the distance between the tip Ppo of said end part 13a and the edge 21c of the platform 21.

[0150] Preferably, the first and third zones Z1, Z3 each correspond to 30% of the total length L. Alternatively, the length of the first zone Z1 could be different from the length of the third zone Z3. For example, the length of the first zone Z1 could be between 20% and 30% of the total length L and the length of the third zone Z3 could be between 20% and 30% of the total length L.

[0151] The gripping module 50 further comprises a module 53 for determining the position of the gripper 25 and in particular a gripping point Pp of the gripper 25.

[0152] The module 53 for determining the position of the gripper 25 is configured to determine a straight line dl passing through the lateral side of the second zone Z2.

[0153] The gripping point Pp is axially offset from the tip Ppo of the end portion 13a by a distance dp.

[0154] The module 53 for determining the position of the gripper 25 further comprises a first image processing processor configured to determine an initial position of the tip or initial gripping point Ppi in the point cloud of the image from the acquisition module 51.

[0155] The image processing processor comprises the following successive steps, illustrated with reference to [Fig.5], with a u,v reference frame dedicated to the image. The processor detects in the image, the region of the platform 21, then a binary thresholding is carried out in this region. The binary thresholding can be carried out using a method known as Otsu.

[0156] In the binary image obtained, the largest contour C is detected, from which extreme pixels are extracted respectively to the left, right and bottom of the contour PT) T) max,g? A max, d A max,b*

[0157] These three pixels are then used to determine the orientation of the end portion 13a of the elastomeric element 13. A first distance between the extreme pixel on the left PmaXjg and the extreme pixel at the bottom Pmax>b is compared, with a second distance between the extreme pixel on the right Pmax>d and the extreme pixel at the bottom Pmax>b. If the first distance is greater than the second distance, that is to say if It || > It -^max,b II , then it is an elas- element left-oriented tomeric, otherwise it is a right-oriented elastomeric element.

[0158] Finally, the pixels of the right lateral edge pdji of the end portion 13a and the pixels of the left lateral edge pgji are detected by searching for the intersection between N vertical lines and the contour C of the second zone Z2 of the end portion 13a of the elastomeric element 13.

[0159] The first camera, of the RGB-D type, also makes it possible to obtain a depth map, called a "depth frame" in Anglo-Saxon terms, superimposed on a color image, to recover depths of points of interest resulting from the image processing carried out on the color image and then calculate the three-dimensional coordinate of each of said points to obtain the three-dimensional image as illustrated in [Fig.6]. Thus, for each pixel of the acquired image, it is possible to recover its depth and then its coordinate in space.

[0160] The first image processing processor is configured to estimate the 3D point of the tip Ppo from the pixel Pmax>b, as well as the left and right lateral 3D points Pgdet Pdji from the pixels pg>iet pd>i respectively

[0161] The first image processing processor is configured to estimate the lines d2, d3 passing through these points Pgiet Pd>i> to calculate the angle 0NST formed between these two lines d2, d3 and to obtain the initial grip point Ppi by projection of the point Ppo, itself projected into the pan defined by the two lines d2, d3.

[0162] The projection distance between these points corresponds to the distance dp previously mentioned.

[0163] The first image processing processor is then configured to translate the initial gripping point Ppi by a distance Ra along the longitudinal axis XI and the extension axis Yl of the second reference frame XI, Yl, ZI associated with the gripper 25, that is to say to the left and to the rear in the case of an elastomeric element 13 oriented to the right or to the right and to the rear in the case of an elastomeric element 13 oriented to the left.

[0164] [Fig.7] illustrates the translation of the initial grip point Ppi by the distance Ra to the left and to the rear in the case of an elastomeric element 13 oriented to the right to obtain the grip point Ppf transmitted to the robotic arm 18 by a transmission module 54.

[0165] The distance Ra corresponds to the radius of the magnets 25a, 25b, 25c of the gripper 25.

[0166] Such a translation of the distance Ra along the longitudinal axis XI of the second reference XI, Y1, ZI makes it possible to increase the magnetization surface of the gripper 25 with the end part 13a of the elastomeric element 13.

[0167] Indeed, the gripper 25 is initially aligned with the straight line dl, it is shifted by the distance -Ra along the longitudinal axis XI of the second reference mark when gripping the end part 13a of the elastomeric element 13 and it is shifted by the distance +Ra along the longitudinal axis XI when laying to cancel this shift.

[0168] We proceed in a similar manner along the extension axis Yl of the second reference XI, Y1,Z1.

[0169] The electronic control unit UCE 40 further comprises a module 60 for anchoring said end 13a on the external surface 16a of the drum 16.

[0170] Once the end portion 13a of the elastomeric element 13 has been grasped by the gripper 25, it is necessary to move it to the drum 16 and anchor it on the external surface 16a of said drum 16.

[0171] To do this, the surface of the end portion 13a is rolled over the outer surface 16a of the drum 16 by applying contact pressure and gradually releasing the anchored portions of the end portion 13a.

[0172] The gripper 25 being rigid, the end portion 13a cannot be anchored on the drum 16 in a single pose. The gripper 25 comprising three rows of magnets 25a, 25b, 25c, 25e, 25f, the anchoring step is carried out in three successive poses Rn, R i2 and Rt3, that is to say one pose per row of magnets 25a, 25b, 25c, 25e, 25f.

[0173] To determine these laying instructions Rn, RT2 and RT3, the anchoring module 60 comprises a laser projection module 61, namely a first fixed vertical red laser L1 indicating the center of the drum 16, a second fixed horizontal green laser L2 indicating the laying azimuth of the elastomeric elements and two variable vertical green lateral lasers L3, L4, indicating the laying longitude, on the external surface 16a of the drum 16.

[0174] The L3, L4 lasers with a wavelength corresponding to the green color are preferred because the green color is more distinguishable from the tire rubber. Indeed, the rubber tends to reflect red, which attenuates the contrast of the lasers. Alternatively, it could be provided that the L3, L4 lasers have a wavelength corresponding to the red color or another color.

[0175] Similarly, lasers L1 and L2 could have a wavelength corresponding to a color other than red, for example green or another color.

[0176] The lasers are fixed on the gantry 28.

[0177] The installation 10 further comprises a second three-dimensional camera (not shown) restoring a cloud of points of coordinates measured in a reference frame associated with said second camera and having a line of sight oriented towards the drum 16 and configured to acquire an image of a laying zone on the external surface 16a of the drum 16.

[0178] The second camera is, for example, an RGB-D sensor.

[0179] The second camera is configured to highlight the different lasers L1, L2, L3, L4. By way of non-limiting example, the second camera can be configured to increase the exposure to capture the light from the lasers, to increase the saturation to highlight the dominant colors and to modify the white balance to highlight the green color.

[0180] The anchoring module 60 comprises a module 62 for acquiring an image of the external surface 16a of the drum 16, in particular of the laying zone, taken by the second camera fixed on the gantry 28 and directed towards the drum 16. The acquired image of the external surface 16a of the drum 16 is visible in [Fig.8].

[0181] The acquisition of the image of the laying zone on the external surface 16a of the drum 16 is carried out before the gripping of the end part 13a of the elastomeric element 13 by the gripper 25 in order to anticipate the trajectory of the robotic arm 18 and to know where to anchor said end 13a.

[0182] Carrying out this acquisition step upstream of the gripping of the end portion 13a of the elastomeric element 13 makes it possible to avoid the fining of said end 13a.

[0183] The anchoring module 60 further comprises a module 63 for processing the image of the installation zone comprising a second image processing processor configured to detect the lasers L1, L2, L3, L4 and a 3D point cloud.

[0184] Said image processing module 63 is further configured to isolate the pixels associated with the lasers in the acquired image using a color segmentation in the image, converted into a saturated image, called hue saturation value, with the acronym TSV or Hue Saturation Value in English terms.

[0185] Said module 63 is configured to detect an intersection pixel p; at the intersection between the second horizontal laser L2 and one of the lateral lasers L3, L4, namely the right lateral laser L3 if the end portion 13a of the elastomeric element 13 is oriented to the right or the left lateral laser L4 if the end portion 13a is oriented to the left.

[0186] The X-X' axis of the drum 16 is defined by the vector between the intersection pixel p, and a pixel in the middle of the drum pm detected at the intersection between the first vertical laser L1 and the second horizontal laser L2.

[0187] Using the depth information from the camera, it is possible to estimate an intersection point ?! and a midpoint Pm corresponding to the three-dimensional points of the intersection pixels p, and the midpoint of the drum pm.

[0188] The anchoring module 60 comprises a module 64 configured to determine the anchoring point Pb P2, P3 of each of the magnets 25a, 25b, 25c relative to the intersection point P^ans a plane Pi (ji) of normal where an adjusted circle C is located in the point cloud of one of the lateral lasers L3, L4 of [Fig.8] and as a function of a distance dr between two rows of magnets 25a, 25b, 25c, 25e, 25f as well as the radius Ra of a magnet 25a, 25b, 25c, 25e, 25f.

[0189] Figure 9 illustrates how the anchor points Pb P2, P3 of each of the rows of magnets 25a, 25b, 25c, 25e, 25f are positioned relative to the intersection point P! in a plane Pi (ji) of normal n„.

[0190] To determine the position of the first anchor point of the first row of magnets 25a on the adjusted circle C, the intersection point PI is rotated around the axis of the circle by an angle 0n according to the following equation:

[0191] [Eq. 1]

[0192] 0IX = RaIR

[0193] With R, the measured radius of the drum 16.

[0194] Respectively, the position of the second and third anchor points P2, P3 of the second and third rows of magnets 25b, 25c on the fitted circle C are defined as follows by pivoting the intersection point P! is pivoted around the axis of the circle respectively by an angle 012 and 013 according to the following equations:

[0195] [Eq. 2]

[0196] 012 = (Ra + d,) / R

[0197] [Eq. 3]

[0198] 0I3= (Ra + 2dr) / R),

[0199] The adjusted circle C with center Pc and radius R is determined as a function of the drum axis, the drum radius and the center of the circle

[0200] The axis of the drum is determined using the vector PTP^n and the radius can be obtained in two ways: by measurement using a rangefinder or by estimating the diameter.

[0201] To determine the center circle Pc, said module 64 is configured to perform a circle adjustment in the 3D point cloud of one of the lateral lasers L3, L4. The equation that we are looking for comes from that of a large circle C in R3, that is to say a circle drawn on a sphere having the same center as the sphere. In other words, it is the intersection between a sphere of the same radius as the drum 16 and a plane passing through the center of this sphere which has the axis of the drum as its normal.

[0202] Let P be any point on the sphere, we obtain the first relation: 102031

[0204] Let ir be the plane of normal in which the great circle is located, we have for any point P; the following relation:

[0205] ■ p^p. = 0

[0206] By developing, we obtain the following equation:

[0207] (Y(_X() + y(Y_y,) +_z.)_Q

[0208] By fixing the radius R and the normal n^-„ we finally seek the point Pc such that, for any point of intersection Pb the following equation is solved numerically: [°2°9] ( ( Xj - xc ) ' + ( y. - yc )2 + ( Zi - zc )2 - R1 ) + ( x ( xc - Xj ) + tu, y ( v. - y. ) + / ¾ z ( zc - zt ) )2 = 0

[0210] Once the circle C is defined, it is necessary to work in a two-dimensional space to carry out the different rotations around the said circle.

[0211] Figure 10A shows the fitted circle C fitted in the laser point cloud. The projection of the intersection point P! on the fitted circle C, Pvc, is rotated around the center of the circle to find the anchor points Pb P2, P3dc each of the magnets 25a, 25b, 25c. This projection is necessary to ensure that all points are on the fitted circle C. The vectors y. and 2. of the anchor points Pb P2, P3are determined using the following relationships:

[0212] Xj = n^ ; et-?.-py

[0213] Thus, the vector y. is defined as the vector product of these vectors, i.e. y^îkXj.

[0214] The second anchoring point P2jTCP of the second row of magnets 25b is determined by translating the second intersection point P2 by a distance dr along the y axis, as illustrated in [Fig.lOB].

[0215] Similarly, the third anchoring point P3jTCp of the third row of magnets 25c, 25e, 25f is determined by translating the third intersection point P2 by a distance 2dr along the y axis. - 3

[0216] The gripper 25 therefore follows the trajectory of the markers R3,tcp, ^ztcp, then Rvtcp in this order to anchor the end part 13a of the elastomeric element 13 at the third point P3, then at the second point P2 and finally at the first point P,.

[0217] Figure 10B shows the offsets to obtain the R^zcp and R^rcp reference points.

[0218] To move from the references R^rcp to Rj,pcp and then from Rizcp to Rçtcp> the robotic arm 18 should ideally follow a trajectory in the involute of a circle to roll the surface of the end portion 13a of the elastomeric element 13 onto the surface 16a of the drum 16 by applying contact pressure. However, given the flexibility of the end portion 13a of the elastomeric element 13 and the short distances between the different anchoring points, we assume that an approximation of these involutes is sufficient. In short, the robotic arm 18 follows a linear trajectory between each anchoring point and only the three calculated anchoring points are transmitted to said arm 18.

[0219] The module 64 for determining the anchoring points is configured to take into account the offsets dpet Ra previously determined when gripping the end portion 13a of the elastomeric element 13.

[0220] The three anchoring points Pi.tcp^tcpPs.tcp are thus offset by the radius -Ra along the longitudinal axis X to compensate for the translation of the entire gripper 25 and the first anchoring point PijTcp is offset by the distance dp along the longitudinal axis X to compensate for the offset relative to the tip of the end portion 13a and finally obtain the anchoring points Pb P2, P3 of each of the magnets 25a, 25b, 25c.

[0221] The anchoring points PB P2, P3 of each of the rows of magnets 25a, 25b, 25c, 25e, 25f are then transmitted to a module 65 for controlling the gripper 25.

[0222] The gripper control module 65 is configured to separately control the magnets 25a, 25b, 25c of the gripper 25 and in particular the actuators (not shown) of each magnet.

[0223] Indeed, when anchoring the end portion 13a of the elastomeric element 13 on the drum 16, the actuators must be deactivated row by row to release the anchored zones of the elastomeric element 13.

[0224] [Fig. 11] illustrates an example of a pneumatic diagram for controlling the actuators of the rows of magnets 25a, 25b, 25c, 25e, 25f of the gripper 25. The second and third actuators are each connected to a secondary pneumatic distributor 26a, 26b, for example of the 5 / 2 type, connected to a main pneumatic distributor 26c, for example of the 5 / 3 type. The first actuator of the first magnet 26a is connected directly to the main pneumatic distributor 26c.

[0225] The anchoring module 60 makes it possible to anchor a product of complex shape on a rounded shape, i.e. the drum, by determining three anchoring points belonging to the same circle.

[0226] The ECU 40 further comprises a lashing module 70 configured to wind the elastomeric element 13 around the drum 16 through a 360° revolution once the end portion 13a of said element 13 is anchored on the external surface 16a of the drum 16, as can be seen in FIGS. 12A and 12B.

[0227] The ECU also comprises a cutting module 80 configured to cut said elastomeric element 13 wound around the drum 16 to the desired length.

[0228] The cutting of the elastomeric elements 13 reinforced with metal fibers must be carried out between and along two metal fibers.

[0229] The cutting module 80 is configured to transmit instructions to one of the robotic arms 18 to insert the cutting tool between two metal wires at an incision point Pinc, to cut to an exit point Ps, to return to the incision point Pinc, then to cut the remainder of the elastomeric element 13 to an end point PF as seen in FIGS. 13A, 13B, 13C and 13D.

[0230] The cutting of the remainder of the elastomeric element 13 up to a final point PF is carried out by synchronizing the robotic arm 18 with the rotation of the drum 16.

[0231] The cutting module 80 comprises a cutting preparation module 81 configured to determine the incision point Pinc.

[0232] The determination of the Pinc incision point is carried out upstream of the anchoring.

[0233] When the elastomeric element 13 is cut and its surface rolled onto that of the drum 16, the exit point Ps of the cut coincides with an initial point of interest P^ as shown in [Fig.l4A]. This point of interest is located at the other end of the hypotenuse of the right triangle formed by the point of the end portion 13a of the elastomeric element 13.

[0234] At the end of the anchoring of the end part 13a of the elastomeric element 13 on the drum 16, the elastomeric element 13 is in the position visible in [Fig.l4B],

[0235] The cutting preparation module 81 is configured to bring the incision point into a manually defined region of interest ROI. Said region of interest ROI is chosen between the mechanical guide GM downstream of the platform 21 and the top of the drum 16 so that the cutting tool has sufficient space to incise the elastomeric element 13.

[0236] In [Fig. 14C], the region of interest ROI is located at the known azimuth Al, itself located at an angle [3 from the azimuth A2 of the horizontal laser L2 where the elastomeric element 13 was anchored during the anchoring step. The target distance between the initial point of interest P^ and the guidance limit is noted Ag.

[0237] Let 1NST be the width of the elastomeric element 13, L the length of the side adjacent to the angle 0NSt and R the radius of the drum 16, to bring the initial point of interest P^ to the azimuth A2 of the laser L2, it is necessary to turn the drum by an angle yL~L!R.

[0238] To bring the initial region of interest Pu into the region of interest ROI, it is therefore necessary to rotate the drum 16 by an angle y = L / R- fi.

[0239] To detect the initial point of interest Pu in the localization area, grazing illumination is used to enable the elastomeric element 13 to be distinguished from the lower layer on the drum 16. This then creates a shadow along the edge of the elastomeric element 13 which defines an outline in the image.

[0240] The cutting preparation module 81 comprises an image processing processor 82 configured to determine the initial point of interest Pu.

[0241] The inputs to the algorithm are the 3D image from the second camera directed towards the drum 16, the depth map and a mask whose white pixels represent the region of interest ROI where the initial point of interest Pu was brought.

[0242] To detect the contours, the image processing processor 82 uses a Sobel filter (not shown) configured to detect by convolution horizontal and then vertical intensity variations. By combining the results, a gradient at each point is obtained.

[0243] In our case, we are only looking for diagonal contours, so the image processing processor 82 applies the Sobel filter with a 3x3 diagonal convolution matrix both times.

[0244] For a left-oriented elastomeric element 13, this matrix is ​​written as follows:

[0245] F 0 12' = -1 0 1 .-2 -1 0.

[0246] For a right-oriented elastomeric element 13, this matrix is ​​written as follows:

[0247] Msd - ' -2 -1 -1 0' 0 1 . 0 1 2.

[0248] Using a diagonal die is optimal for elastomeric elements whose end portion 13a forms an angle of 45° with the transverse axis Y. Another angle of the end portion 13a could be provided.

[0249] Next, the image processing processor 82 is configured to use a binary thresholding method to obtain a black and white image of the results and configured to focus in the region of interest ROI to detect the largest contour of the image to isolate it in a black and white image.

[0250] For each line of the image that contains at least one white pixel, only the rightmost pixel (for a left-oriented elastomeric element 13) is kept in order to refine the contour as close as possible to the elastomeric element 13. Then, the contour is dilated to the right only using a dilation function with a convolution vector k = [1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0].

[0251] The image processing processor 82 is then configured to perform a new contour search and search for the convex hull of this contour to obtain a polygon with vertices represented by pixels.

[0252] This step allows reducing the number of pixels in the contour to work only with the vertices of the convex hull. Thus, a pixel p is determined as being the lowest vertex among the two leftmost vertices.

[0253] During the cutting movement, the cutting tool must not strike either the mechanical guide or the drum 16. This is why it is necessary that the point of interest ?! is at a distance Ag±e from the mechanical guide GM.

[0254] To measure this distance Ag±e, the image processing processor 82 uses a pixel pdir which is the highest vertex among the two leftmost vertices.

[0255] The line dNST is the line in the 2D image defined by two pixels p, and pg. The pixel pg corresponds to the intersection of the line dNST and a line dg in the image defined manually and representing the limit of the mechanical guidance.

[0256] The distance between the points and Pg, coming from the pixels p, and pg, is compared with the distance Ag. If the initial point of interest Pu is too close to the mechanical guidance GM, then the effector 20 risks being blocked by it, and if the initial point of interest Pu is too far away, the effector 20 risks being blocked by the drum 16.

[0257] The image processing processor 82 performs a shift of the elastomeric element 13 so that the initial point of interest P^ from the pixel p is at a distance Ag, ideal for the incision movement. This shift is performed by a rotation of the drum 16, the direction of rotation of which depends on the sign of the shift to be performed.

[0258] For example, Ag=0.055m and e=0.01.

[0259] After having detected the initial point of interest Pu and verified the distance Ag between this point and the mechanical guide GM, the elastomeric element 13 is swung by the swung module 70 before carrying out the cutting operation, i.e. winding the elastomeric element 13 around the drum 16. This operation is carried out by synchronizing the rotation of the drum 16 with the rotation of the reel 15.

[0260] Once the elastomeric element 13 is engaged, [Fig. 15A] shows the initial point of interest PI,i, determined before the engagement and the final point of interest PF,i which is the physical point of interest belonging to the elastomeric element 13 and which has therefore rotated around the drum 16 with it.

[0261] The cutting module 80 comprises a module 83 for determining the incision point Pinc as a function of the initial point of interest Pu and a constant distance hOffset between said incision point Pinc and the exit point Ps necessary for the cutting phases illustrated in FIGS. 13A, 13B, 13C.

[0262] The constant distance hoffset is predetermined in prior steps which will not be described.

[0263] The incision point Pinc is located at an axial offset Xoffset = sine^y • hoffse{ from the initial point of interest Pu along the axis X-X' of the drum 16, as in [Fig.l5B].

[0264] The length loffset between the exit point Ps and the initial point of interest Pu is written as follows:

[0265] ^offset ^offset ' COsSy^y

[0266] As shown in Figure 15C, the rotation angle q> to effect the locking of the elastomeric element 13 is therefore not 2ir but is equal to 2 / r- <Pojsset où offset “ loffset! R-

[0267] Thus, the exit point Ps merges with the final point of interest PFi once the elastomeric element 13 is glued to the drum 16.

[0268] The cutting module 80 further comprises a module 84 for heating the cutting tool (not shown).

[0269] The cutting module 80 further comprises a module 85 for analyzing the axial forces Fx and transverse forces Fy of the robotic arm 18 generated during the cutting operation, configured to acquire said force by a force sensor mounted on the robotic arm 18, to determine the cutting exit point Ps and to correct in real time the angle of the cutting tool during the cutting operation.

[0270] Finally, the ECU 40 comprises a welding module 90 configured to press the elastomeric element 13 as close as possible to the cut and to control a multi-profile pressure roller capable of rolling in all directions and accompanying the elastomeric element 13 as the cut progresses.

[0271] The welding module 90 is also configured to control a welding tool, called a zipper in English terms, configured to bring the cut ends of the elastomeric element 13 together in a first direction and in a second direction along the weld.

[0272] The flowchart illustrated in [Fig. 16] illustrates certain manufacturing steps of a method 100 for manufacturing tire blanks.

[0273] The method 100 comprises a step 140 of successively placing elastomeric elements 13 using the manufacturing installation 10.

[0274] To this end, the method 100 comprises, prior to the laying step 140, a step 110 of supplying the laying station 14 with elastomeric element 13, using the supply station 12, the element to be laid taking the form of a continuous strip or sheet.

[0275] The feeding step 110 comprises a step 111 of gripping a container, such as a reel 15, a reel 38 comprising a reel 15 or a roller table, by a multi-axis industrial robot 34 or an autonomous trolley. Each container comprises an elastomeric element to be placed. The feeding step 110 further comprises a step 112 of positioning the container so that the elastomeric element is in a condition to be placed and of unrolling the elastomeric element 13 until its end 13a is placed on the surface 21a of a platform 21 of the installation 10.

[0276] The laying step 140 is controlled automatically by the ECU 40. One of the robotic arms 18, equipped with the gripper 25, automatically places the elastomeric element 13 on the drum 16 for manufacturing tire blanks according to the following sequence.

[0277] The laying step 140 comprises a sequence comprising a step 150 of gripping the end portion 13a of the elastomeric element 13, a step 160 of anchoring said end 13a on the external surface 16a of the drum, a step 170 of clamping the elastomeric element 13 around the drum, a step 180 of cutting the elastomeric element 13 to the desired length and a step 190 of welding the cut portion of the elastomeric element with the anchored end portion 13a.

[0278] The step 150 of gripping the end portion 13a of the elastomeric element 13 comprises a step 151 of acquiring the image of the end portion 13a of the elastomeric element 13 on the platform 21 by the first RGB-D camera.

[0279] The gripping step 150 further comprises a step 152 of cutting the image of the end portion 13a of the elastomeric element 13 on the platform 21 into three zones Z1, Z2, Z3 as described previously with reference to the module 52 for cutting the image of the end portion 13a.

[0280] The gripping step 150 comprises a step 153 of determining the position of the gripper 25 and in particular a gripping point Pp using an image processing processor as described previously with reference to the module 53 for determining the position of the gripper 25.

[0281] The gripping step 150 comprises a step 154 ​​of correcting the initial gripping point Ppi by translating said initial gripping point Ppi by a distance Ra along the longitudinal axis XI and the extension axis Y1 of the reference frame of the gripper 25 to obtain the gripping point Ppf using the image processing processor as described previously with reference to the module 53 for determining the position of the gripper 25.

[0282] The grip point Ppf is then transmitted, during a transmission step 155, to the robotic arm 18

[0283] During step 160 of anchoring said end 13a on the external surface 16a of the drum 16, contact pressure is applied and the anchored parts of the end part 13a are gradually released.

[0284] The anchoring step 160 comprises a step 161 of laser projection and a step 162 of acquiring an image of the external surface 16a of the drum 16 taken by a second RGB-D camera directed towards drum 16.

[0285] Steps 161 and 162 are carried out before step 155 of gripping the end portion 13a of the elastomeric element 13 by the gripper 25 in order to anticipate the trajectory of the robotic arm 18 and to know where to anchor said end 13a.

[0286] The lasers comprise a first vertical laser L1, for example red, fixed indicating the center of the drum 16, a second horizontal laser L2, for example green, fixed indicating the azimuth of installation of the elastomeric elements and two variable vertical lateral lasers L3, L4, for example green, indicating the installation longitude.

[0287] The anchoring step 160 further comprises a step 163 of processing the image of the laying zone during which the lasers L1, L2, L3, L4 and a 3D point cloud are detected, the pixels associated with the lasers in the acquired image are isolated and the intersection pixel p is detected; at the intersection between the second horizontal laser L2 and one of the lateral lasers L3, L4, namely the right lateral laser L3 if the end portion 13a of the elastomeric element 13 is oriented to the right or the left lateral laser L4 if the end portion 13a is oriented to the left. The image processing step 163 is carried out using the image processing module 63 previously described.

[0288] The anchoring step 160 further comprises a step 164 determining the anchoring point Pb P2, P3 of each of the rows of magnets 25a, 25b, 25c, 25e, 25f relative to the intersection point P; in a plane Pi (jt) of normal where there is an adjusted circle C in the cloud of points of one of the lateral lasers L3, L4 and as a function of a distance dr between two rows of magnets 25a, 25b, 25c as well as the radius Ra of a magnet 25a, 25b, 25c.

[0289] The anchoring point Pb P2, P3 of each of the rows of magnets 25a, 25b, 25c, 25e, 25f is determined with reference to the module 64 for determining the anchoring points as described previously.

[0290] The anchoring step 160 further comprises a step 165 of transmitting the anchoring points PB P2, P3 of each of the rows of magnets 25a, 25b, 25c, 25e, 25f to a control module 65 of the gripper 25 configured to separately control the rows of magnets 25a, 25b, 25c, 25e, 25f of the gripper 25 and in particular the actuators of each row of magnets.

[0291] During step 170 of securing the elastomeric element 13 around the drum, the elastomeric element 13 is wound around the drum 16 through a 360° revolution once the end portion 13a of said element 13 is anchored on the external surface 16a of the drum 16.

[0292] The step 180 of cutting the elastomeric element 13 to the desired length comprises a step 181 of preparation for cutting during which an incision point Pinc is determined corresponding to the point of insertion of the cutting tool between two metal wires, using the module 81 of preparation for cutting as described above. cededly.

[0293] Step 181 of preparation for cutting is carried out upstream of step 170 of loading.

[0294] During the cutting preparation step 181, a region of interest ROI and an initial point of interest Pu are determined as described previously with reference to the cutting preparation module 81 and the image processing processor 82.

[0295] The cutting step 180 further comprises a step 183 of determining the incision point Pinc as a function of the initial point of interest Pu and a constant distance hoffset between said incision point Pinc and the exit point Ps necessary for the cutting phases illustrated in FIGS. 13A, 13B, 13C, as described previously with reference to the module 83 for determining the incision point Pinc.

[0296] The cutting step 180 further comprises a step 184 of heating the cutting tool during the cutting operation 186 and a step 185 of analyzing the axial forces Fx and transverse forces Fy of the robotic arm 18 generated during the cutting operation 186 configured to acquire said force by a force sensor mounted on the robotic arm 18, to determine the cutting exit point Ps and to correct in real time the angle of the cutting tool during the cutting operation 1586.

[0297] During step 190 of welding the cut portion of the elastomeric element with the anchored end portion 13a, the elastomeric element 13 is pressed as close as possible to the cut and a multi-profile pressure roller is controlled capable of rolling in all directions and accompanying the elastomeric element 13 as the cut 186 progresses.

[0298] During the welding step 190, a welding tool, called a zipper in English terms, is controlled, configured to bring the cut ends of the elastomeric element 13 together in a first direction and in a second direction along the weld.

[0299] The installation system and method according to the invention is designed to adapt to both existing manual installations and new installations.

Claims

Claims

1. Installation (10) for manufacturing tire blanks associated with a first orthogonal reference frame (X, Y, Z) and comprising a drum (16) for manufacturing tire blanks movable in rotation about an axis of rotation (X-X') of the first reference frame, a platform (21) arranged upstream of the drum (16), extending along a transverse axis (Y) of the first reference frame and comprising a flat surface (21a) for receiving one end (13a) of an elastomeric element (13), at least one robotic arm (18), an electronic control unit (40) configured to control the robotic arm (18), and at least one first three-dimensional camera restoring a cloud of points of coordinates measured in a reference frame associated with said first camera and having a viewing axis oriented towards the platform (21) and configured to acquire an image of the end portion (13a) of the elastomeric element (13) on the platform (21),characterized in that the robotic arm (18) comprises at least one gripper (25) associated with a second orthogonal reference mark (XI, Yl, Zl) distinct from the first reference mark (X, Y, Z) and configured to grip the end portion (13a) of the elastomeric element (13) from above and comprising at least three rows of elements made of magnetic material (25a, 25b, 25c, 25e, 25f) parallel to each other and regularly spaced from each other along an extension axis (Y 1) of the second reference mark (XI, Yl, Zl), and in that the electronic control unit (40) comprises at least: - a module (50) for gripping the end portion (13a) of the elastomeric element (13) configured to determine a gripping point (Pp) of the gripper (25) as a function of the point cloud restored by the first camera, and - a module (60) for anchoring said end (13a) on the external surface (16a) of the drum (16) configured to determine an anchoring point (Pb P2,P3) of each of the rows of magnetic material elements (25a, 25b, 25c, 25e, 25f) on the external surface (16a) of the drum (16).,

2. Installation (10) according to claim 1, in which the end portion (13a) extends along the extension axis (Yl) of the second reference mark (XI, Yl, Zl) angularly offset from the transverse axis (Y) of the first reference mark (X, Y, Z).

3. Installation (10) according to claim 1 or 2, in which the module (50) for gripping comprises: - a module (51) for acquiring the image of the end portion (13a) of the elastomeric element (13) on the platform (21) by the first camera, - a module (52) for cutting the image of the end portion (13a) of the elastomeric element (13) on the platform (21) into three zones (Z1, Z2, Z3), and - a module (53) for determining the gripping point (Pp) comprises a first image processing processor configured to determine an initial gripping point (Ppi) in the point cloud of the image from the acquisition module (51) and to correct said initial gripping point (Ppi) by translating said initial gripping point (Ppi) by a distance (Ra) corresponding to the radius of the magnetic elements (25a, 25b, 25c, 25e, 25f) of the gripper (25) along the extension axis (Yl) of the second reference point (XI, Y1,ZI) and along a second longitudinal axis (XI) of the second reference point perpendicular to said extension axis (Yl) and to determine the grip point (Ppf) transmitted to the robotic arm (18) by a transmission module (54).,

4. Installation (10) according to any one of the preceding claims, comprising a first fixed vertical laser (L1) indicating the center of the drum (16), a second fixed horizontal laser (L2) indicating the laying azimuth of the elastomeric element and two variable vertical lateral lasers (L3, L4) indicating the laying longitude, said lasers being integral with a fixed structure (28) of the installation, and in which the anchoring module (60) comprises a module (61) for projecting said lasers (L1, L2, L3, L4) onto the external surface (16a) of the drum (16).

5. Installation (10) according to claim 4, comprising a second three-dimensional camera restoring a cloud of points of coordinates measured in a reference frame associated with said second camera and having a line of sight oriented towards the drum (16) and configured to acquire an image of a laying area on the external surface (16a) of the drum (16), and in which the anchoring module (60) comprises: - a module (62) for acquiring an image of said laying area, and - a module (63) for processing the image of said laying area comprising a second image processing processor configured to detect the lasers (L1, L2, L3, L4) and an intersection pixel (pO at the intersection between the second horizontal laser (L2) and one of the lateral lasers (L3, L4) and to estimate an intersection point (PO and a point of the middle (Pm) corresponding to the three-dimensional points of the intersection pixels (pO and the middle of the drum (pm).

6. Installation (10) according to any one of the preceding claims, in which the electronic control unit (40) further comprises a module (170) for clamping the elastomeric element (13) around the drum (16), a module (180) for cutting the elastomeric element (13) to the desired length and a module (190) for welding the cut part of the elastomeric element (13) with the anchored end part (13a) on the external surface (16a) of the drum (16).

7. Installation (10) according to any one of the preceding claims, in which the gripper (25) of the robotic arm (18) comprises actuators each connected to an element made of magnetic material (25a, 25b, 25c, 25e, 25f), said actuators being controlled separately to successively release the third row of elements made of magnetic material (25c, 25e, 25f), the second row of elements made of magnetic material (25b) then the first row of elements made of magnetic material (25a).

8. Installation (10) according to any one of the preceding claims, in which the magnetic material elements (25a, 25b, 25c, 25e, 25f) of the gripper (25) of the robotic arm (18) are mounted on a support (25d) configured to be connected to the end portion of the robotic arm (18).

9. Installation (10) according to any one of the preceding claims, in which the first, second and third rows of magnetic material elements of the gripper of the robotic arm each comprise at least one magnetic material element.

10. Installation (10) according to claim 8, in which the first and second rows of magnetic material elements of the gripper of the robotic arm each comprise a single magnetic material element and in the third row comprises at least three magnetic material elements (25c, 25e, 25f), one of the magnetic material elements (25c) of the third row being aligned along the extension axis (Yl) of the second reference mark (XI, Yl, Zl) with the magnetic elements (25a, 25b) of the first and second rows.

11. Installation (10) according to any one of the preceding claims, comprising a second robot arm.

12. Installation (10) according to any one of the preceding claims, in which the platform (21) comprises at least one magnetic strip (21b) extending along a longitudinal axis (X) parallel to the axis of rotation (X-X') of the drum (16) and arranged on the receiving surface (21a) of the platform (21).

13. Method for automatically and successively fitting elastomeric elements (13) using a tire blank manufacturing installation (10) associated with a first reference frame (X, Y, Z) and comprising a tire blank manufacturing drum (16) rotatable about an axis of rotation (X-X'), a platform (21) arranged upstream of the drum (16), extending along a transverse axis (Y) of the first orthogonal reference frame (X, Y, Z) and comprising a flat surface (21a) for receiving one end (13a) of an elastomeric element (13), at least one robotic arm (18), and at least one first three-dimensional camera reproducing a cloud of points of coordinates measured in a reference frame associated with said first camera and having a sighting axis oriented towards the platform (21) and configured to acquire an image of the end portion (13a) of the elastomeric element (13) on the platform (21),the robotic arm (18) comprising at least one gripper (25) associated with a second orthogonal reference mark (XI, Yl, Zl) distinct from the first reference mark (X, Y, Z) and configured to grip the end portion (13a) of the elastomeric element (13) from above, and comprising at least three rows of elements made of magnetic material (25a, 25b, 25c, 25e, 25f) parallel to each other and regularly spaced from each other along an extension axis (Yl) of the second reference mark (XI, Yl, Zl), characterized in that it comprises at least: - a laying step (140) comprising a sequence comprising at least one step (150) of gripping the end portion (13a) of the elastomeric element (13), during which a gripping point (Pp) of the gripper (25) is determined as a function of the cloud of points restored by the first camera; and - a step (160) of anchoring said end (13a) on the external surface (16a) of the drum, during which an anchoring point (Pb P2,P3) of each of the rows of magnetic material elements (25a, 25b, 25c) on the external surface (16a) of the drum (16).,

14. Method (100) according to claim 13, wherein said end portion (13a) extends along an extension axis (Yl) of the second reference mark (XI, Yl, Zl) angularly offset from the transverse axis (Y) of the first reference mark (X, Y, Z) and wherein the step (150) of gripping the end portion (13a) of the elastomeric element (13) comprises a step (151) of acquiring the image of the end portion (13a) of the elastomeric element (13) on the platform (21) by the first camera, a step (152) of cutting the image of the end portion (13a) of the elastomeric element (13) on the platform (21) into three zones (Zl, Z2, Z3), a step (153) of determining the position of an initial gripping point (Ppi) of the gripper (25) in the point cloud of the image acquired in the acquisition step (151) using a processing processor, a step (154) of correcting the initial gripping point (Ppi) by translating the initial gripping point (Ppi) by a distance (Ra) corresponding to the radius of each of the magnetic material elements (25a, 25b, 25c) of the gripper (25) according to the extension axis (Yl) of the second reference point (XI, Yl,Zl) and along a second longitudinal axis (XI) of the second reference point perpendicular to said extension axis (Y 1) to obtain the gripping point (Ppf) and a step (155) of transmitting said gripping point (Ppf) to the robotic arm (18) with a view to gripping the end part (13a) of the elastomeric element (13) by the gripper (25).,

15. Method (100) according to claim 14, in which the anchoring step (160) comprises a step (161) of projecting lasers (L1, L2, L3, L4) and a step (162) of acquiring an image of a laying area on the external surface (16a) of the drum (16) taken by a second three-dimensional camera restoring a cloud of points of coordinates measured in a reference frame associated with said second camera and having a line of sight oriented towards the drum (16), said steps of projecting lasers and acquiring an image (161, 162) are carried out before the step (155) of taking the end portion (13a) of the elastomeric element (13) by the gripper (25), the lasers (L1, L2, L3, L4) comprising a first vertical, fixed laser (L1) indicating the center of the drum (16), a second fixed horizontal laser (L2) indicating the azimuth of installation of the elastomeric elements and two variable vertical lateral lasers (L3, L4) indicating the installation longitude.

16. The method (100) of claim 15, wherein the anchoring step (160) further comprises: - a step (163) of processing the image of the installation area, during which the lasers (L1, L2, L3, L4) and the point cloud restored by the second camera are detected, the pixels associated with the lasers (L1, L2, L3, L4) are isolated in the image acquired during the acquisition step (162) and the intersection pixel (pO) at the intersection between the second horizontal laser (L2) and one of the lateral lasers (L3, L4), - a step (164) determining the anchoring point (Pb P2, P3) of each of the rows of elements made of magnetic material (25a, 25b, 25c, 25e, 25f) relative to the point of intersection (PO in a plane (Pi (ji)) of normal (n^) where an adjusted circle (C) is located in the point cloud of one of the lateral lasers (L3, L4) and as a function of a distance (dr) between two rows of elements made of magnetic material (25a, 25b, 25c) as well as the radius (Ra) of an element made of magnetic material (25a, 25b, 25c) of the gripper (25), and - a step (165) of transmitting the anchoring points (PB P2, P3) of each of the rows of elements made of magnetic material (25a, 25b, 25c, 25e, 25f) to a module (65) for controlling the gripper (25) configured to separately control the rows of elements made of magnetic material (25a, 25b, 25c, 25e, 25f) of the gripper (25).

17. Method (100) according to any one of claims 13 to 16, comprising, prior to the laying step (140), a step (110) of supplying elastomeric element during which the end portion (13a) of the elastomeric element (13) is laid on the surface (21a) of a platform (21) of the installation (10).

18. A method (100) according to any one of claims 13 to 17, wherein the sequence of the laying step (140) further comprises a step (170) of clamping the elastomeric element (13) around the drum, a step (180) of cutting the elastomeric element (13) to the desired length and a step (190) of welding the cut portion of the elastomeric element (13) with the end portion (13a) anchored on the external surface (16a) of the drum (16).

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