FR2858083A1 - Identity authentication system uses electronic processor to compare a person's signature and analyse their behaviour when writing it - Google Patents

Abstract

System consists of a sensory surface (1) with a dynamic stress detector (2) coupled to it, connected to an electronic processor (3) that uses a suitable algorithm to analyse the signal from the sensory surface and deliver a signal that compares a person's signature with their behaviour when writing it. The system consists of a sensory surface (1) with a dynamic stress detector (2) coupled to it, connected to an electronic processor (3) that uses a suitable algorithm to analyse the signal from the sensory surface and deliver a signal that compares a person's signature with their behaviour when writing it. The stress detector contains piezo-active elements (6), e.g. piezoelectric ceramics or plastics, piezoresistive, magneto- electric, capacitive or optical devices.

Description

Description

  The present invention relates to an authentication and identification device for securing access to areas, places or vehicles or authorize the use of a device or service.

  The purpose of authentication and identification devices is to prove the identity of the person requesting access to a place, a service or a machine. To prove your identity, there are different solutions that concern what we have (card, badge, document), what we know (password, code) or what we are. The last solution refers to biometrics, which consists of identifying a person on the basis of automatically recognizable and verifiable physical characters or behavioral traits.

  The access control market has opened up with the proliferation of systems, but none is effective against fraud, because most use an external identifier such as badge, card, key, code. These external identifiers may be stolen, lost or falsified. Passwords and codes can be stolen or forgotten. To overcome these drawbacks, authentication procedures can become very restrictive for the user (memorization of codes, change of passwords, etc.). It is therefore obvious that the only non-falsifiable authentication is to refer not to a external identifier but to the person himself. This is what biometrics allows.

  At present, it can be considered that there are two categories of biometric technologies: o Techniques for analyzing human morphology (fingerprints, hand shape, facial features, drawing of the venous network of the eye, retinal scanning , voice ...) o Behavior analysis techniques: * The way to use a computer keyboard (pressure exerted, typing speed ...) * The dynamics of the signature (speed of movement, accelerations In general, the techniques for analyzing human morphology are considered to be expensive because they use very sophisticated sensor and signal processing technologies. Some of these techniques are relatively uncomfortable and intrusive like retinal scanning. Others are not very accurate when considering their rate of false 30 acceptances (voice, shape of the hand or face). As far as behavioral analysis techniques are concerned, they are generally considered as inexpensive, not very intrusive but not very precise and rather greedy in data processing and storage power.

  To overcome these drawbacks, the present invention aims to provide a 3s means of authentication and identification safe and cheap based on the analysis of an electrical signal generated by a sensitive surface on which the user draws a graphic or sign characterizing it (signature, initials, graphic code). This device is similar to the dynamic analysis of a signature without having the complexity.

  Indeed, the analysis of a dynamic signature requires specific tablets or touch panels 40 to analyze the graphical aspect of the signature through a sensor grid for digitizing the signature in space. Other devices, quite complex, use the placement in the space of a digital pen with different sensors (acceleration and pressure).

  Conversely, the present invention does not require any sensor array on the sensitive surface or any particular object to analyze the graphics. In one of its preferred embodiments, the present invention utilizes a simple piezoelectric element coupled to the sensitive surface to generate the clean and unique electrical signal to each user.

  In the field of piezoelectric elements applied to authentication and identification devices, mention may be made of US4833279 (1999) Digital computer writing board which uses an array of piezoelectric elements to detect the position of a stylus on a touch screen. Another patent (US-2002053857 2002- Piezoelectric identification device and application thereof) uses sheets of PVDF-type piezoelectric plastics material to provide a multilayer sensor array for fixing the image of a fingerprint. A patent (FR62674051 1992 - Device for identifying a person, especially by fingerprint detection) of the same type but using a different technology makes it possible to record fingerprints.

  All these techniques use touch panels designed using sensor network technologies, electrode grids, rather complex multilayers leading to 60 pixelate (or digitize) graphics. The reliability and accuracy of these authentication devices rely on the performance and definition of the associated sensor network.

  On the other hand, the sensor network technologies implemented use relatively expensive and sophisticated manufacturing means close to the semiconductor industry or the printed circuit.

  In contrast, the present invention aims to provide a very simple, inexpensive, reliable and robust authentication and identification device based essentially on: o The spectral analysis of the temporal signal generated by the realization of the graphic o The memorization by learning a reference graphic.

  o Simple coupling technology of one or more electroactive elements.

  o Comparison of authentication graphics with reference graphics.

  The subject of the present invention is therefore an authentication and identification device, comprising a sensitive surface (1) on which is coupled a dynamic stress sensor (2) linked to a processing electronics (3) making it possible to analyze by a suitable algorithm, the signal from the sensitive surface, characterized in that said device delivers an electrical signal correlated both to the geometric layout of a figure and the pulse necessary for this plot. This double correlation makes it possible to authenticate the signature, initials or graphical code of a person by basing this authentication not only on the originality of the graphic design but also on the impulse, specific to each, during the realization of this graphics.

  Preferably, the sensitive surface (1) is a plate of robust insulating or conducting material comprising at least one electroactive element which generates a signal when the sensitive surface 85 is mechanically stressed during the production of the graphic.

  Advantageously, the electroactive element or elements are made of piezoelectric material such as ceramics or plastics of the PVDF type.

  Advantageously, the electroactive element or elements are coupled to the plate by bonding but mechanical coupling by any means of attachment can also be achieved.

  According to a first embodiment, the plate comprising the piezoelectric element or elements is biased in bending, but any other mode of mechanical stressing can be used.

  According to this same embodiment, the plate is fixed at its edges, but other mechanical fasteners can be made insofar as the performances of the device are not related to the embodiments of the sensitive surface. According to this embodiment, the size of the plate may be variable depending on whether the graphics are done with the finger or with a stylus-like object.

  According to a first embodiment, the processing electronics (3) consists of a housing placed at a distance from the sensitive surface, but this electronics could be integrated with the sensitive surface 100. Advantageously, this electronics comprises a signal processor and storage means for analyzing the signals and storing them.

  Advantageously, the processing electronics includes software for defining an algorithmic analyzing the time and frequency signals. Advantageously, the processing software includes a learning mode for constituting and storing reference signals. Advantageously, the processing software compares the authentication and identification signal with the reference signals. Advantageously, the processing electronics rejects or accepts the authentication and identification signal.

  Advantageously, the processing electronics triggers an audible or light warning when the authentication signal is rejected. Upon acceptance of the authentication signal, a sound or light warning may be issued signaling acceptance. Advantageously, the processing electronics sends a control signal to different organs controlling an access, a device or a service.

  Advantageously, the sensitive surface will not be supplied with energy, insofar as, in a preferred embodiment, it uses one or more piezoelectric elements which generate the authentication signal by the simple mechanical stressing of the sensitive surface. .

  According to a variant of the device, the authentication signal produced by the sensitive panel may be used to power a radio frequency transmitter which will transmit this same signal to the processing electronics that will be deported.

  The device according to the invention is intended for various access control applications which will be given, without this being a limitation to its applications, some examples.

  The device according to the invention can be installed as a standalone device but the sensitive surface can also be a constituent part of the building elements such as doors, windows, displays and supporting structures, to control access to places or spaces. 125 This concept of space is clearly extended to all means of transport. - 5

  The device according to the invention can be used or integrated in devices or devices (screen, housings, mechanical or plastic structure) requiring authentication before use. No restriction is to be made on the types of devices that can come from applications as varied as telematics, computing, industrial equipment, home automation, telecommunications, medical equipment, etc.

  Hereinafter, we will first describe a first embodiment with reference to FIGS. 1, 2, 3 and 4.

  With reference to FIG. 1, it can be seen that the plate (4) is fixed on a fixed frame (5) in such a way as to tolerate a bending movement of this plate. This plate comprises a piezoelectric element (6) glued on its underside. This plate being of conductive material, a single electrode (7) is connected to the processing electronics (3), the other electrode being the mass (8). Referring to Fig. 2, when a stylus finger or object draws a graph or sign (9), the plate (4) is mechanically biased. The piezoelectric sensor 140 (6) translates this mechanical stress into a temporal signal (10) which accounts for both the shape of the graph and the dynamic pressure exerted during its production. These two characteristics are specific to the person who draws this graph or sign. Figure 2 gives an example (or sample) of time signal corresponding to an original graph or sign (Alpha). Figure 3.1 corresponds to a reference signal 145 previously stored and Figure 3.2 to an authentication signal which will be analyzed and compared to the reference signal. Figures 4.1 & 4.2 correspond to other samples respectively of reference signal and authentication signal. The processing electronics (3) comprises a processor and associated software that makes it possible to compare any authentication signal with the reference signals previously stored in memory during the learning phase.

Claims (13)

claims:   1. Authentication and identification device, comprising a sensitive surface (1) on which is coupled a dynamic stress sensor (2) linked to a processing electronics (3) for analyzing, by an appropriate algorithm, the signal from the sensitive surface, characterized in that the said device delivers an electrical signal related to the pulse generated by a given pattern thus imbrigating, in the same signal, a confidential code (the plot) and a behavioral characteristic (l impulse of the plot) specific to each individual.   2. Device according to claim 1, wherein the dynamic stress sensor consists of piezoelectric elements such as piezoelectric, piezoresistive, magnetoelectric, capacitive or optical.   3. Device according to claim 1, wherein the sensitive surface is itself made of piezoelectric materials either piezoelectric ceramics or piezoelectric plastics for example PVDF type.   4. Device according to claim 1, wherein the sensitive surface is biased in flexion or compression and on which are coupled one or more piezoelectric elements regardless of the nature of the material and the manner of arranging them.   5. Device according to claims 1 & 4, wherein the sensitive surface is made of insulating or conductive materials such as, for example, glass, stainless steel, aluminum or plastic without any restriction on the nature of the material of the surface is given.   6. Device according to claims 1, wherein the sensitive surface consists of building elements such as windows, doors, displays and more generally supporting structures located in places requiring access control.   7. The device according to claim 1, wherein the sensitive surface consists of building elements such as screens, housings or mechanical structures in any device or device requiring authentication before use.   8. Device according to claims 1, in which the graphic code or the signature are inscribed on the sensitive surface with either the finger or with a stylus-type object.   9. Device according to claim 1, wherein the electronics is used to acquire the signals, process them by spectral analysis and save them.   10. Device according to claim 1, wherein the electronics makes it possible to store reference signals by learning.   11. Device according to claim 1 & 3, wherein the sensitive surface is not powered by an electrical source.   12. Device according to claim 1 & 3, wherein the useful authentication signal is used to provide energy to a radiofrequency transmitter.   13. Apparatus according to claim 12, wherein the radio frequency transmitter transmits the useful authentication signal to a processing electronics having a receiver.