LU83333A1 - USE OF SURFACE TEXTURES AS A SINGLE IDENTITY MARK - Google Patents

Description

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USE OF DS SURFACE TEXTURES AS A RANDOM BRAND OF UNIQUE IDENTITY.

i ^ Object of the present invention is the realization of a method which uses | reads the texture or surface condition of an object to be able to characterize and identify it in a unique way.

We can thus recognize an object or part of the object by a ca-! ·%.

an unchanging characteristic of its own.

The possibilities of identifying objects are numerous; for example, we have known the principle of identification for a long time, but the j-seal is an object in itself that we seek to recognize; after i must guarantee that the seal belongs to the object it protects. It is therefore ! it of limited reliability and poorly resistant to fraud.

! i: j In the field of facility control, we have nuclear structures, j! Random tagging techniques are already used. Cr. can quote 1-

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Innrcu-age by dispersion of solid particles in a solid matrix; the immutable nature being the distribution of the particles as well as their size, frozen once and for all within a solid volume; the means of measurement calls upon the ultrasonic waves and their reflection in the heterogeneous system ^ which, with the revealing transducer employed must constitute an immutable whole.

i 1 Recognition requires an ultrasonic transmission of information, that is to say an exact repositioning of the transducer, and an absolute identicity between transducers used successively, compared to the three-dimensional network of dispersed particles, i-in this case therefore, the character uses ultrasonic waves to be measured; it is not directly revealed. In addition, very special Lechnologies are necessary, j Γ ’- 2 - i: To alleviate the above drawbacks, according to the invention proposes a new method for identifying objects.

J Any solid object is limited to a surface. If a solid object is injectable by nature, its surface, considered as an inseparable envelope, is i! as well. Without the usual conditions, the surirce â'ur. object ctr.trirue dljà à j j its identification.

We therefore propose to use the texture or surface condition of the objects to be able to characterize them in a uniform way.

The surface must present in the area where it is used, a certain - random character; this is generally the case in terms of surface roughness | these mechanics. If it is used as it came from construction, it will be said to be natural. If necessary, it will be locally transformed by overwiring; dd _ f | or scratching or surface scraping to give it a well random texture, that is to say an adequate marking.

it (f ILThe texture, natural or imparted, is the immutable character. Its record, by feeler, pen or any other means, is the means of identification.

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According to the main characteristic of the invention, part of the surface of the object to be identified is taken, the information contained in a profile of said surface is analyzed and said profile is recorded.

According to another characteristic of the invention, the signals of. profile of the surface to be analyzed are transposed and sampled in the frequency domain f '.

The attached figure shows how the section of a mechanical surface pre- | feels a random topographic aspect. The uniqueness of the cut comes from the richness of resident information! on the surface of an object: i! ’F I * - 3 - '; peaks, valleys, plateaus, heights, directions, etc. when it is e. ·: plcrée i ri '1, 1 at the desired scale.

ί A _i s Consequently, if two surfaces have dimensions and aspects similar to the manufacturing scale (tolerance, finishes, profile), one can always find, at a finer scale, a state of roughness which can differentiate. In our case, it is the asperity element and the valley element and their location that are important.

Then arises, for identification, the problem of the exact repositioning of the probe in front of the section explored previously;

It has been verified that a part placed on a simple st.mtif fitted with a lug, when it is replaced another time on the same stntif, gives the same | information.

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The redfepositioning can be of two types: the identity 1 plate or other support) is brought to 1'-ppmr. it d · .. · sure, it s.1: put here brand i 'transportable; or else the apparatus is "-η- 'at 1 · structured-rrrruru and it is then a fixed mark.

The surface profile signal can be viewed directly on paper or it can be digitized, that is to say we count the asperities, we measure the heights, the distances and we obtain a digital key of the said

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signal.

Profile sigals can also be transposed and sampled in the frequency domain, so that partial spectra can be used as an identity key to a texture.

The identification method proposed by this patent makes it possible to guarantee structures already, protected by conventional seals. It - h - i can in itself constitute a sealing technique. Iron example, the threaded rod and bolt assembly can be filed flush and constitute a single mark; if someone were to unscrew the bolt, they could never re-screw it and reposition it exactly in relation to the screw. Profile measurement, straddling screws and bolts, would detect this fraud.

This method lends itself well to the identification of objects using their own topographic texture, without having to practice a reference hole in them. rence. As for example: paintings, statues or furniture, the other 11 or methods or techniques of identification would not be possible without in-do: mqger the work of art.

| j Another advantage of our method is that the j | reading can be small and -not require large; means for cor.mef identification is the case for piezo-i transducers! electric.

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Claims (3)

11. Method for identifying objects by surface texture analysis, characterized in that the tone takes up a part of the surface of the object to be identified, the information contained in a profile of said surface is analyzed and said said is recorded profile. 2. A method of identifying objects by surface texture analysis according to claim 1, characterized in that the signals of the profile * of the surface to be analyzed are transposed and sampled in the frequency domain. . 3) Method for identifying objects by surface texture analysis according to claim 1, characterized in that the surface part to be analyzed has been previously treated. I k) Method of identifying objects by surface texture analysis (according to claims 1 and 3i characterized in that the surface part to be analyzed has been sanded. 5. Method of identifying objects by surface texture analysis according to claims 1 and 3, characterized in that the exploration scale is variable. V s * !!!!!!!!! } i J i _ LuxerfcGur ”, t r.a: l -; l; 1 & fccrr-ieEicn! ff * W \ 'f · lu F'1 “I \ o. \ t> /