WO2019116401A1

WO2019116401A1 - Three-dimensional mapping machine for leather or similar material covered objects

Info

Publication number: WO2019116401A1
Application number: PCT/IT2017/000280
Authority: WO
Inventors: Matteo Mascetti
Original assignee: Camoga S.P.A.
Priority date: 2017-12-15
Filing date: 2017-12-15
Publication date: 2019-06-20

Abstract

A three-dimensional mapping machine for leather or similar material covered objects comprises a support defining a working volume for housing an object and scanning means connected to the support and suitable to define a line of sight towards an area to be mapped onto the object itself; the mapping machine further comprises dynamic variation means of the arrangement and/or the relative position between the covered object to be mapped and the scanning means.

Description

DESCRIPTION

THREE-DIMENSIONAL MAPPING MACHINE FOR LEATHER OR

SIMILAR MATERIAL COVERED OBJECTS

Technical Field

The present invention relates to a so-called mapping "machine" (of the surface) of three-dimensional leather or similar materials (artificial leather, adherent films of various nature and so on) covered objects, and in particular the present invention refers to the "mapping" functionality of such objects meaning that with such operation a scan of the surface of the objects themselves is carried out aimed at detecting the uniformity of deposition of the leather (or similar material) as well as detecting the presence of any defects and/or any contributions of other material, which, in turn, will be identified in terms of nature, position and conformation.

Background art

As is known, in different production fields three-dimensional objects are made which are then covered with film or with (more or less thin) layers of natural or synthetic leather (or also, depending on the needs, of fabric or polymeric material of various nature): an example of these production fields is given by the automotive sector, where it is common to find three- dimensional objects - having a highly variable and complex form - such as steering wheels or gear levers, internal handles or compartment panels and so on.

In the realization of such objects on an industrial level, especially where high quality and/or high cost products are produced (or again, where particularly valuable cover materials are used), a particular verification and control function of the leather "assembled" by overlapping to the objects themselves is necessary, and it is necessary the dimensional and geometric verification of the seams themselves where this leather (or similar material) has been assembled by means of seams or similar implementation systems,

In this operating environment, therefore, it is necessary to obtain a verification, on the finished three-dimensional object, both of the correct application of the leather, and the absence of defects in the leather (cuts, tears, stretches resulting from the deposition/assembly on the object and so on) and the seams or the "constraint means" similar to the seams.

Among the numerous technologies available nowadays for the three- dimensional scanning of objects, at this point we must point out some drawbacks, which are generally constituted by the remarkable specificity of the verification operations required in the cases illustrated above: in fact, although it is possible to make preliminary checks on the leather when it is still in a state "separated" by the three-dimensional object (and typically, the same Applicant of the present invention has developed various technologies in this sense to scan leather remnants arranged on a plane or on a mechanical abutment that allows its localized pretensioning), such verifications are not repeatable - with the same machinery and with the same execution methods - on the assembled/finished three-dimensional objects due to the considerable complexity of form that the objects themselves can assume.

Furthermore, the verification of the seams (or of the constraint systems and/or deposition and/or tensioning of the surface) of the leather on three- dimensional objects requires, in addition to the need to take into account a non-planar scanning surface, the implementation of particular analysis criteria and reprocessing of the scanned image, due precisely to the particular geometries or topologies that the seams realize on the surface of the object itself (and also due to the very particular types of defects that can be detected in a seam, such as, e.g., a "skipped stitch", an interruption of the sewing thread, a variable distance between the points where the needle has made its entry or exit with respect to the leather and so on).

The methods and machineries used nowadays for the scanning of three- dimensional objects also present some drawbacks in terms of operation speed and accuracy, always linked to the need of mapping an object having a complex shape in a working time as short as possible and taking into account the optimal scanning conditions that materials such as leather (or similar) require from an lighting application/optical point of view.

Detailed description of the invention

In comparison with the known art and the above-mentioned problems, the object of the present invention is therefore to provide a mapping machine of three-dimensional covered objects which overcomes the drawbacks of the known art.

More specifically, the object of the present invention is to implement a mapping machine which has a very high accuracy in the scanning of even complex three-dimensional shapes and which can detect both possible defects of the leather and of the mechanical means of surface constraint and/or of surface tensioning of the leather itself with respect to the object on which it was placed.

The object of the invention is also to provide a mapping machine which can discriminate and "classify", at least at the level of signalling to an operator, the different possible types of differences or defectives, and which is therefore also characterized by a high ergonomic/functional compatibility both as regards the loading and unloading of the object in the mapping machine and as regards the viewing of possible defects.

Furthermore, an object of the present invention is to devise a mapping machine that guarantees an optimal handling of even very complex three- dimensional objects, ensuring the possibility of scanning the entire surface of these objects themselves even in the presence of portions with concavities or convolutions particularly difficult to reach or difficult to access at least from the optical point of view.

Is now described, by way of example and not of limitation, an embodiment of the mapping machine of three-dimensional covered objects according to the invention, as shown in the accompanying figures, wherein:

- Figure 1 shows a perspective schematic view of a machinery according to the invention; and

- Figure 2 shows a schematic perspective view of a subset of functional components of the machinery of Figure 1 ;

The mapping machine according to the invention is globally indicated by the reference numeral 1 in the accompanying figures and from the functional point of view it is designed to operate on "covered" objects, which, for the purposes of the present invention, can be considered as such when they consist of a base body (which may be, for example, the steering wheel rim, including, in turn, spokes and hub, or also an armrest of an armchair and so on) and a cover element overlapped and/or tensioned at least locally on the base body by surface constraint means. From the structural point of view, the machine 1 comprises a support 2 (e.g. shaped according to a hollow parallelepiped, as in the appended figures) which in turn defines a working volume 2a within which it is possible to position, in at least one spatial arrangement, a covered object "O" (which, in effect, is to be mapped); there are also suitable scanning means 3 which are connected to the support 2 and are suitable to define a line of sight towards an area to be mapped "M" positioned "locally" on the covered object.

Advantageously, the mapping machine 1 according to the invention further comprises means of dynamic variation 4 of the arrangement and/or of the relative position between the covered object to be mapped and at least the scanning means 3: such means of dynamic variation 4 are suitable to define a plurality of areas to be mapped M, which, in turn, cooperatively define a fraction of the surface of the covered object which, depending on the needs of the moment, can also cover the entire surface of the covered object itself.

Going into detail and referring to the attached figures, it can be seen that the dynamic variation means 4 comprise a manipulation assembly 4a which can be constraint to the scanning means 3 and/or the covered object (such handling assembly 4a is able to configure the covered object in a plurality of arrangements and/or positions in the working volume 2a) and also comprise a collimation assembly 4b associated in relation complementarity to the scanning means 3 and/or to the object O, (which, instead, is suitable to configure the scanning means 3 in a plurality of pointing conditions towards the covered object in which a line of sight is constantly defined towards said plurality of areas to be mapped M).

With reference to the accompanying figures and in order to clarify the meaning of the expression "relation complementarity" just introduced, it can be seen that the handling assembly 4a is constrained to the scanning means 3 while the collimation assembly 4b is associated with the object to be mapped O (in the figures, a steering wheel for vehicles) but naturally according to the invention the opposite constraint/association condition can occur (i.e. the handling assembly 4a can be associated with the object O to be mapped while the collimation assembly 4b can be constrained to the scanning means 3).

Advantageously, the handling assembly 4a can be active in cooperation with a collimation assembly 4b, so as to guarantee the maximum "optical freedom" of the lines of sight towards any point of the surface of the (covered) object O to be scanned: in other words, the collimation assembly 4b and the handling assembly 4a are cooperatively active to define a direct line of sight without obstacles (such line of sight is then subtended by the sensor means 3 towards the area to be mapped M) on the covered object independently of any position and/or arrangement within the working volume 2a.

The functional cooperation between the handling assembly 4a and the collimation assembly 4b can give rise to different kinematic combinations, depending on the needs of the moment: e.g., it is possible that both assemblies 4a and 4b are simultaneously movable within the working volume 2a, or it is also possible that one of the two assemblies 4a or 4b is stationary with respect to the other (and in these last two alternative cases only the assembly 4a or only the assembly 4b will move while the other will remain stationary in the working volume 2a).

In even greater detail, the handling assembly 4a comprises a robotic arm: in its turn, such robotic arm can be of an anthropomorphic type and can define a predetermined number of degrees of rotational and/or translational freedom which, e.g., will be equal to or greater than five.

It should be noted that the constraint of the covered object to be mapped to the handling assembly 4a could result in a coverage, at least temporarily, of a part of the surface (to be mapped!) of the object itself: for this purpose, the handling assembly 4a can provide two or more constraint points which can be operated selectively (and alternatively with respect to one another) on two different areas of the covered object "O" or the scanning means 3, or it may even be possible to make the same points/constraint tools act on two different areas in successive moments, from a temporal point of view, on the covered object.

Instead, focusing on the collimation assembly 4b, it can be seen how the latter comprises a roto-translation kinematics (which, according to the requirements of the moment, can also be of the translational or rotary type, e.g., comprising a sliding guide) on which the scanning means 3 or the object O are movably engaged: such roto-translation kinematics can be structurally simplified with respect to the robotic arm which constitutes the handling assembly 4a and defines a relative movement path of the scanning means 3 in the working volume 2a around the covered object O.

In a possible embodiment (exemplary and not limiting!) of the invention, the aforementioned relative movement path can comprise a curved segment having a predefined arc length: such curved segment, in turn, lies on an (ideal) plane of collimation and, depending on the needs of the moment, it is possible to provide the collimating assembly 4b with suitable kinematic means which make the aforementioned arc length and/or the collimating plane movable in the space at least within the working volume 2a.

The functionality of the scanning means 3, which as previously seen must be able to determine the plurality of areas to be mapped M, must take into account the maximization of the precision and accuracy of the scanning itself (which is of fundamental importance for allowing an equal unequivocal and precise processing of scanning data): for this purpose it should be noted that the invention can advantageously provide that on the covered object the different lines of sight - which, in turn, correspond to the plurality of areas to be mapped - have always a normal orientation to the area to be mapped M itself: this condition of "constant normality of the line of sight" is, in fact, guaranteed by the coordinated movements of the handling assembly 4a and of the collimation assembly 4b.

From the point of view of the surface detection, it should be noted that the scanning means 3 can typically comprise suitable optical sensors active in the wavelengths of visible or invisible light, and (depending on the needs of the moment) of both "active" type, e.g., acting by sending a light or laser beam to the surface to be scanned, and "passive" i.e. simply able to receive the visual image of the area to be mapped.

These optical sensors must however be suitable to detect visual and/or surface characteristics of the covered object so as to make a comparative comparison or in any case so as to detect discontinuity in the images deriving from the scanning/mapping: for this purpose, the visual and/or surface characteristics which can be perceived by optical sensors can typically include:

- combinations of chromatographic and/or illumination and/or contrast parameters corresponding to reference chromatographic and/or illumination and/or contrast parameters associated with a nominal condition of the covered object and/or of said covering element (e.g., "nominal" parameters of colour, surface texture or reflexivity of the leather with which the object has been covered); and/or

- combinations of chromatographic and/or illumination and/or contrast parameters corresponding to reference chromatographic and/or illumination and/or contrast parameters associated with a nominal condition of the surface constraint means of said covered object (e.g., "nominal" parameters of colour, position, surface direction and "regularity" of the visible seam on the covered object); and/or

- combinations of chromatographic and/or illumination and/or contrast parameters corresponding to reference chromatographic and/or illumination and/or contrast parameters associated with a plurality of defective conditions of the covered object and/or covering element and/or surface constraint means (e.g., tears or abrasions or "bubbles" in the leather, areas with chromatic dystonia, interruptions of the seams or irregularities in the sewing stitches and so on).

Finally, always with reference to the attached figures, it can be noted that in the mapping machine 1 lighting control means 5 may be present, active at least on an area to be mapped 5 to determine an (optimal) illumination level: more in detail, the aforementioned lighting control means 5 may comprise:

- a predetermined number of illuminating spots 5a cooperatively active with the scanning means 3 and preferably focused on the area to be mapped M (such illuminating spots can move solidly with the optical sensors 3 or can, in any case, move on the collimation element 4b); and/or

- a predetermined number of illuminating and/or reflecting and/or shielding walls 5b arranged in the working volume 2a, which can be typically (dynamically or selectively, both in space and time) oriented with respect to the covered object in order to minimize reflections and/or refractions and/or light refractions with respect to the area to be mapped M.

As a further possible structural characteristic of the invention, it can be seen in the attached figures the presence of suitable display means 6 suitable to project a representative image to a machine operator (and possibly elaborated both in an optical sense and in any possible sense of information overlapping or digital modification) of the area to be mapped M: said display means are connected at least to the scanning means 3 to receive a data flow.

The invention allows to obtain several advantages over the known art.

First of all, thanks to the peculiar constructive architecture of the mapping machine, and in particular thanks to the presence of the anthropomorphic robotic handler, it is possible to obtain a combination of movements and "arrangement positioning" of the three-dimensional object combined with a plurality of positioning and/or pointing of the sensor means: this allows to perform always complete and accurate mappings.

Moreover, it is possible to obtain a high degree of "surface resolution" of the mappings, together with a high precision and speed of execution of the measurements themselves: this occurs both for the detection of possible defective characteristics of the leather (or similar material!) and of possible defective characteristics of the seams (or similar mechanical constraint and/or tensioning means).

Furthermore, it should be noted that the present invention always manages to guarantee the optimal conditions of "localized viewing" of the area to be mapped both in terms of guaranteeing a clear line of sight and in terms of determining, on this line of sight and on the area to be mapped, the right conditions of brightness and absence of reflections or refractions/dispersions that can distort the mapping itself.

It is finally evident that to the object of the present invention modifications or additions can be applied, which are obvious to a person skilled in the art, without departing from the scope of protection provided by the appended claims.

Claims

1. Machine for mapping three-dimensional covered objects, said covered objects (O) preferably comprising a base body and a covering element overlapped and/or tensioned at least locally on said base body by means of surface constraint, said machine (1) comprising:

- a support (2) defining a working volume (2a), at least one three- dimensional covered object being positioned in at least one spatial arrangement in said working volume (2a); and

- scanning means (3) connected to the support (2) and suitable to define a line of sight towards an area to be mapped (M) on said covered object (O), characterized in that it further comprises means for dynamic variation (4) of the arrangement and/or the related position between the covered object (O) to be mapped and at least the scanning means (3), said dynamic variation means (4) being preferably suitable to define a plurality of areas to be mapped (M) cooperatively defining the entire surface of the covered object (O).

2. Machine according to claim 1 , wherein the dynamic variation means (4) comprise a handling assembly (4a) that can be constrained to the covered object, (O) and/or to the scanning means (3), said handling assembly (4a) being able to configure the covered object (O) and/or the scanning means (3) in a plurality of arrangements and/or positions in the working volume (2a).

3. Machine according to claims 1 or 2, wherein the dynamic variation means (4) comprise a collimation assembly (4b) associated with the scanning means (3) and/or the covered object (O), said collimation assembly (4b) being suitable to configure the scanning means (3), preferably in cooperation with the handling assembly (4a), in a plurality of pointing conditions towards the covered object (O) in which a line of sight is constantly defined towards said plurality of areas to be mapped (M).

4. Machine according to any one of the preceding claims, wherein the handling assembly (4a) comprises a robotic arm.

5. Machine according to claim 4, wherein said robotic arm is of the anthropomorphic type.

6. Machine according to any one of claims 4 or 5, wherein the robotic arm defines a predetermined number of degrees of rotational and/or translational freedom, said degrees of freedom being preferably equal to or greater than five.

7. Machine according to any one of the preceding claims, wherein the collimation assembly (4b) comprises a roto-translation kinematics, preferably comprising a sliding guide, on which the scanning means (3) and/or the covered object (O) are movably engaged, said sliding guide defining a relative movement path of the scanning means (3) in the working volume (2a) and around the covered object (O).

8. Machine according to any one of the preceding claims, wherein said relative movement path comprises a curved segment having a predefined arc length and lying on a collimation plane, said arc length and/or said collimation plane being preferably movable in space at least within the working volume (2a).

9. Machine according to any one of the preceding claims, wherein the scanning means (3) are suitable to determine said plurality of areas to be mapped (M) on the covered object (O) so that lines of sight corresponding to said plurality of areas to be mapped always have a normal orientation to the area to be mapped (M) itself, the scanning means (3) preferably comprising a predetermined number of optical sensors suitable to detect visual and/or surface characteristics of the covered object (O), said visual and/or surface characteristics even more preferably comprising:

- combinations of chromatographic and/or illumination and/or contrast parameters corresponding to reference chromatographic and/or illumination and/or contrast parameters associated with a nominal condition of said covered object (O) and/or said covering element; and/or

- combinations of chromatographic and/or illumination and/or contrast parameters corresponding to reference chromatographic and/or illumination and/or contrast parameters, said reference parameters being associated with a nominal condition of said surface constraint means on said covered object (O); and/or

- combinations of chromatographic and/or illumination and/or contrast parameters corresponding to reference chromatographic and/or illumination and/or contrast parameters associated with a plurality of defective conditions of said covered object (O) and/or said covering element and/or said surface constraint means.

10. Machine according to claim 9, wherein there are also lighting control means (5) active at least on an area to be mapped (5) to determine an illumination level, said lighting control means (5) comprising:

- a predetermined number of illuminating spots (5a) cooperatively active with the scanning means (3) and preferably focused on the area to be mapped (M); and/or

- a predetermined number of illuminating and/or reflecting and/or shielding walls arranged in the working volume (2a) and which can be preferably oriented with respect to the covered object so as to minimize reflections and/or refractions and/or light refractions with respect to the area to be mapped (M).