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WO2001029575A1 - System for electromagnetic detection and identification of objects by acoustic excitation - Google Patents

System for electromagnetic detection and identification of objects by acoustic excitation Download PDF

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Publication number
WO2001029575A1
WO2001029575A1 PCT/FR1999/002665 FR9902665W WO0129575A1 WO 2001029575 A1 WO2001029575 A1 WO 2001029575A1 FR 9902665 W FR9902665 W FR 9902665W WO 0129575 A1 WO0129575 A1 WO 0129575A1
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Prior art keywords
detection
marker
transmitter
objects
antenna
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PCT/FR1999/002665
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French (fr)
Inventor
Didier Spada
Emmanuel Thommerel
Jean-Christophe Valmalette
Jean-Raymond Gavarri
David Marchais
Gilles Nolibe
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Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S13/00—Systems using the reflection or reradiation of radio waves, e.g. radar systems; Analogous systems using reflection or reradiation of waves whose nature or wavelength is irrelevant or unspecified
    • G01S13/74—Systems using reradiation of radio waves, e.g. secondary radar systems; Analogous systems
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S15/00—Systems using the reflection or reradiation of acoustic waves, e.g. sonar systems
    • G01S15/86—Combinations of sonar systems with lidar systems; Combinations of sonar systems with systems not using wave reflection
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S11/00—Systems for determining distance or velocity not using reflection or reradiation

Definitions

  • the present invention relates to a system for electromagnetic detection and identification of objects by acoustic excitation makes it possible to locate and identify remotely, any object comprising a Piezo-Electro-Magnetic (PEM) sensor.
  • PEM Piezo-Electro-Magnetic
  • the patented system concerns both the PEM sensor, the exciter or device allowing it to be excited by an acoustic wave, as well as the receiver-reader or device allowing the reading of the electromagnetic signal returned by the sensor, (FIG. 1).
  • the originality of this invention lies in the possibility offered by this type of PEM marker to be detected remotely through a medium which may be homogeneous or heterogeneous of the solid, liquid or gaseous type.
  • Orra pellera marker a material or set of materials or complex device, 15 placed near or on an object whose location is to be ensured from a distance, and capable of delivering a characteristic signal.
  • a piezoelectric component is produced from a polarizable material, which, under the action of an external pressure (constraints) or under the action of a vibration, delivers an electric current I.
  • An electromagnetic component consists of a material or an inductance capable of generating an electromagnetic field or wave (conventional coil of inductance L).
  • the marker system considered is capable of being excited by an acoustic wave and emitting an electromagnetic wave.
  • piezoelectric material sintered ceramic PZT with an approximate chemical formula Pb Zr 0
  • Foucault. are easily detectable up to depths of the order of 60 cm, using coil type antennas (magnetometers) [4].
  • Piezoelectric transducers are also used in vibration detection and positioning applications [9]. From these various applications, we therefore propose to create a system capable of both locating and identifying a target, and this, at an emitter-marker distance of the order of 1.50 m.
  • the PEM marker system is first composed of a piezoelectric material (P), possibly an element acting as a transfer function (T), and finally, a transmitting antenna (A).
  • P piezoelectric material
  • T transfer function
  • A transmitting antenna
  • This system can be subjected either to a pressure constraint, or to an acoustic or vibratory wave, or to a mechanical impulse: it delivers under these various actions a correlated electromagnetic response.
  • the system is sensitive to at least one frequency of mechanical, acoustic, vibrational excitation.
  • the piezoelectric element has at least one resonant frequency.
  • the transfer function allows the non-linearity of the signal in order to make it more complex, inducing for example a coding (possibly use of a varistor or an electronic chip).
  • the electric current flowing in the antenna emits a signal in the form of an electromagnetic wave.
  • the system receiving this signal consists of an antenna and a signal processing module.
  • the support of the system is either a rigid polymer plate or a flexible polymer film.
  • the antenna A is produced directly on the support, either by means of a conductive paint, a photoetching or by mechanical etching (pigmented composite support): ( Figure 2). The characteristics are shown in Figure 2.
  • the piezoelectric component P is installed directly on the antenna support ( Figures 3 and 4). The layout is visible in the figure. The dimensions of the piezoelectric component P are variable and adapted to a given resonant frequency.
  • the transfer function T can be arranged between the component P and the antenna A.
  • This function T can be provided in various ways: introduction into the manufacture of a semiconductor element, of an electronic component of varistor type with non-linear response, an electronic chip comprising a processor element and memory, etc.
  • the transmitter has the function of directing an acoustic wave (or pulse) towards the marker: shock emitter, train of vibrational waves, etc.
  • a loudspeaker can act as a complex transmitter.
  • This transmitter can transmit simple (mono or multi chromatic) or complex waveforms (broadband frequency functions)
  • the function of the receiver-reader is to capture the electromagnetic wave re-emitted by the marker and to process it.

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  • Engineering & Computer Science (AREA)
  • Radar, Positioning & Navigation (AREA)
  • Remote Sensing (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Geophysics And Detection Of Objects (AREA)

Abstract

The invention concerns a device for the location and remote identification of any object comprising a piezo electromagnetic sensor (PEM). The system concerns both the PEM sensor, the drive or device for sound wave excitation and the receiver-reproducer for reading the electromagnetic signal returned by the sensor. Said device is designed for remote detection of objects, bearing or incorporating said type of PEM marker, through a solid, liquid or gaseous medium which may be homogeneous or heterogeneous.

Description

Système de détection et d'identification électromagnétique d'objets par excitation acoustiqueElectromagnetic object detection and identification system by acoustic excitation

La présente invention concerne un système de détection et d'identification électromagnétiques d'objets par excitation acoustique permet de localiser et d'identifier à distance, tout objet comportant un capteur Piezo-Electro-Magnétique (PEM). Le système breveté concerne à la fois le capteur PEM, l'excitateur ou dispositif permettant de l'exciter par une onde 5 acoustique, ainsi que le récepteur-lecteur ou dispositif permettant la lecture du signal électromagnétique renvoyé par le capteur, (figure 1)The present invention relates to a system for electromagnetic detection and identification of objects by acoustic excitation makes it possible to locate and identify remotely, any object comprising a Piezo-Electro-Magnetic (PEM) sensor. The patented system concerns both the PEM sensor, the exciter or device allowing it to be excited by an acoustic wave, as well as the receiver-reader or device allowing the reading of the electromagnetic signal returned by the sensor, (FIG. 1).

L'originalité de cette invention réside dans la possibilité qu'offre ce type de marqueur PEM d'être détecté à distance au travers d'un milieu qui peut être homogène ou hétérogène de type solide, liquide ou gazeux. 10The originality of this invention lies in the possibility offered by this type of PEM marker to be detected remotely through a medium which may be homogeneous or heterogeneous of the solid, liquid or gaseous type. 10

DEFINITIONSDEFINITIONS

Orra pellera marqueur un matériau ou ensemble de matériaux ou dispositif complexe, 15 disposé à proximité ou sur un objet dont on veut assurer la localisation à distance, et capable de délivrer un signai caractéristique.Orra pellera marker a material or set of materials or complex device, 15 placed near or on an object whose location is to be ensured from a distance, and capable of delivering a characteristic signal.

Un composant piézoélectrique est réalisé à partir d'un matériau polarisable, qui, sous l'action d'une pression externe (contraintes) ou sous l'action d'une vibration, délivre un courant électrique I.A piezoelectric component is produced from a polarizable material, which, under the action of an external pressure (constraints) or under the action of a vibration, delivers an electric current I.

20 Un composant électromagnétique est constitué d'un matériau ou d'une inductance capable de générer un champ ou une onde électromagnétique (bobine classique d'inductance L).An electromagnetic component consists of a material or an inductance capable of generating an electromagnetic field or wave (conventional coil of inductance L).

Le système marqueur considéré est capable d'être excité par une onde acoustique et d'émettre une onde électromagnétique.The marker system considered is capable of being excited by an acoustic wave and emitting an electromagnetic wave.

D'où notre définition de "marqueur Piézo-Électro-Maqnétique" ou marqueur PEM.Hence our definition of "Piezo-Electro-Maqnetic marker" or PEM marker.

2525

Exemples de matériau piézo-électrique adapté : la céramique frittée PZT de formule chimique approchée Pb Zr 0|5 Ti 0.5 03.Examples of suitable piezoelectric material: sintered ceramic PZT with an approximate chemical formula Pb Zr 0 | 5 Ti 0 .5 0 3 .

30 ETAT DE L'ART.30 STATE OF THE ART.

La recherche d'objets enfouis a fait l'objet de nombreuses études. Il existe ainsi de nombreux détecteurs de métaux capables de discriminer les cibles en fonction de leur conductivité et s'affranchissant de la minéralisation du sol ( [1 ],[2] et [3] ). 35 Ces détecteurs sont basés sur le principe de détection par recherche des courants deThe search for buried objects has been the subject of numerous studies. There are thus many metal detectors capable of discriminating targets based on their conductivity and bypassing the mineralization of the soil ([1], [2] and [3]). 35 These detectors are based on the principle of detection by searching for

Foucault. Ces derniers sont aisément détectables jusqu'à des profondeurs de l'ordre de 60 cm, à l'aide d'antennes de type bobines (magnétomètres) [4].Foucault. The latter are easily detectable up to depths of the order of 60 cm, using coil type antennas (magnetometers) [4].

D'autres systèmes de détection existent actuellement sur le marché : ce sont les radars de prospection minière. Ceux-ci permettent de localiser des objets ou métaux enfouis à de grandes profondeurs (200 - 300 m), mais à la condition qu'ils soient de volumes importants. Ces détecteurs sont essentiellement basés sur des mesures de moments magnétiques et sur des mesures d'hytérésis ( [5] et [6] ).Other detection systems currently exist on the market: these are mining prospecting radars. These make it possible to locate objects or metals buried in great depths (200 - 300 m), but on condition that they are of large volumes. These detectors are essentially based on measurements of magnetic moments and on measurements of hyteresis ([5] and [6]).

Des systèmes de repérage et de positionnement par détection de moments magnétiques existent déjà, notamment dans le domaine de la navigation sous-marine. Le problème de ce marquage est qu'il faut faire au préalable des mesures du champ terrestre, puis des comparaisons de moments magnétiques ( [7] et [8] ).Marking and positioning systems by detection of magnetic moments already exist, particularly in the field of underwater navigation. The problem with this marking is that it is necessary to make measurements of the earth's field first, then comparisons of magnetic moments ([7] and [8]).

Les transducteurs piézo-électriques sont également utilisés dans des applications de détection de vibrations et de positionnement [9]. A partir de ces diverses applications, nous proposons donc de créer un système capable à la fois de localiser et d'identifier une cible, et ce, à une distance émetteur- marqueur de l'ordre de 1 ,50 m.Piezoelectric transducers are also used in vibration detection and positioning applications [9]. From these various applications, we therefore propose to create a system capable of both locating and identifying a target, and this, at an emitter-marker distance of the order of 1.50 m.

LE MARQUEUR PEM.THE PEM MARKER.

1) Le système marqueur PEM est d'abord composé d'un matériau piézo-électrique (P), éventuellement d'un élément faisant office de fonction de transfert (T), et enfin, d'une antenne émettrice (A).1) The PEM marker system is first composed of a piezoelectric material (P), possibly an element acting as a transfer function (T), and finally, a transmitting antenna (A).

2) Ce système peut être soumis soit à une contrainte de pression, soit à une onde acoustique ou vibratoire, soit à une impulsion mécanique : il délivre sous ces diverses actions une réponse électromagnétique corrélée.2) This system can be subjected either to a pressure constraint, or to an acoustic or vibratory wave, or to a mechanical impulse: it delivers under these various actions a correlated electromagnetic response.

3) Le système est sensible à au moins une fréquence d'excitation mécanique, acoustique, vibrationnelle. L'élément piézo-électrique possède au moins une fréquence de résonance.3) The system is sensitive to at least one frequency of mechanical, acoustic, vibrational excitation. The piezoelectric element has at least one resonant frequency.

4) Sous l'effet de l'excitation, l'élément piézo-électrique crée un courant électrique.4) Under the effect of the excitation, the piezoelectric element creates an electric current.

5) Celui-ci peut être éventuellement modifié par le biais de la fonction de transfert (T) : ce courant modifié est enfin envoyé dans l'antenne A.5) This can be modified if necessary via the transfer function (T): this modified current is finally sent to antenna A.

6) La fonction de transfert permet la non - linéarité du signal afin de le rendre plus complexe, induisant par exemple un codage (éventuellement utilisation d'une varistance ou d'une puce électronique).6) The transfer function allows the non-linearity of the signal in order to make it more complex, inducing for example a coding (possibly use of a varistor or an electronic chip).

7) Le courant électrique circulant dans l'antenne émet un signal sous forme d'une onde électromagnétique. 8) Le système récepteur de ce signal est composé d'une antenne et d'un module de traitement du signal.7) The electric current flowing in the antenna emits a signal in the form of an electromagnetic wave. 8) The system receiving this signal consists of an antenna and a signal processing module.

MONTAGE ET MODE DE REALISATIONASSEMBLY AND EMBODIMENT

1) Le support du système est soit une plaque rigide polymère soit un film souple polymère.1) The support of the system is either a rigid polymer plate or a flexible polymer film.

2) L'antenne A est réalisée directement sur le support, soit par le biais d'une peinture conductrice, d'une photogravure ou par gravure mécanique (support composite pigmenté) : (figure 2). Les caractéristiques sont indiquées sur la figure 2.2) The antenna A is produced directly on the support, either by means of a conductive paint, a photoetching or by mechanical etching (pigmented composite support): (Figure 2). The characteristics are shown in Figure 2.

3) Dans le cas d'une gravure mécanique sur un composite chargé de pigments métalliques, l'action mécanique d'une pointe, ou thermique d'un laser, induit un sillon conducteur électrique.3) In the case of mechanical etching on a composite charged with metallic pigments, the mechanical action of a point, or the thermal action of a laser, induces an electrically conductive groove.

4) Le composant piézo-électrique P est implanté directement sur le support - antenne (figures 3 et 4). La disposition est visible sur la figure. Les dimensions du composant piézo-électrique P sont variables et adaptées à une fréquence de résonance donnée.4) The piezoelectric component P is installed directly on the antenna support (Figures 3 and 4). The layout is visible in the figure. The dimensions of the piezoelectric component P are variable and adapted to a given resonant frequency.

5) Les jonctions sont métalliques.5) The junctions are metallic.

6) La fonction de transfert T peut être disposée entre le composant P et l'antenne A. Cette fonction T peut être assurée de diverses manières : introduction dans la fabrication d'un élément semi-conducteur, d'un composant électronique de type varistor à réponse non linéaire, d'une puce électronique comprenant un élément processeur et de la mémoire, etc..6) The transfer function T can be arranged between the component P and the antenna A. This function T can be provided in various ways: introduction into the manufacture of a semiconductor element, of an electronic component of varistor type with non-linear response, an electronic chip comprising a processor element and memory, etc.

7) L'émetteur à pour fonction de diriger une onde acoustique (ou impulsion) vers le marqueur : émetteur de chocs, train d'ondes vibratoires, etc.. Un haut-parleur peut faire fonction d'émetteur complexe. Cet émetteur peut émettre des formes d'ondes simples (mono ou multi chromatiques) ou complexes (fonctions à large bande fréquentielle)7) The transmitter has the function of directing an acoustic wave (or pulse) towards the marker: shock emitter, train of vibrational waves, etc. A loudspeaker can act as a complex transmitter. This transmitter can transmit simple (mono or multi chromatic) or complex waveforms (broadband frequency functions)

8) Le récepteur-lecteur à pour fonction de capter l'onde électromagnétique ré-émise par le marqueur et de la traiter.8) The function of the receiver-reader is to capture the electromagnetic wave re-emitted by the marker and to process it.

9) L'émetteur et le récepteur sont reliés entre eux afin de corréler les ondes émises et les ondes reçues. REFERENCES9) The transmitter and the receiver are linked together in order to correlate the waves transmitted and the waves received. REFERENCES

[1] Métal detector for discriminatory détection of buried objects, US Patent nβ 4096432[1] Metal detector for discriminatory detection of buried objects, US Patent n β 4096432

[2] Métal detecting appartus having improved ground effect immunity, US Patent nβ 3823365[2] Metal detecting appartus having improved ground effect immunity, US Patent n β 3823365

[3] Métal detector for distinguishing between precious métal objects and other métal objects, US Patent n° 3875498[3] Métal detector for distinguishing between precious metal objects and other metal objects, US Patent n ° 3875498

[4] James E. Lenz, Procceeding of the IEEE, vol 78, nβ6, 1990.[4] James E. Lenz, Procceeding of the IEEE, vol 78, n β 6, 1990.

[5] Geophysical surveying with audio frequency eictromagnetic fields and orthogonal receiver coils, US Patent n° 3617866[5] Geophysical surveying with audio frequency eictromagnetic fields and orthogonal receiver coils, US Patent n ° 3617866

[6] P. Lastargues, Magnétisme en géologie et prospection magnétique au sol, ED. Masson et Cie[6] P. Lastargues, Magnetism in geology and magnetic prospecting on the ground, ED. Masson et Cie

[7] Magnetic marker position fixing System for underwater vehicles, US Patent n° 5357437[7] Magnetic marker position fixing System for underwater vehicles, US Patent n ° 5357437

[8] Underwater buried mine classifier, US Patent n° 4766385[8] Underwater buried mine classifier, US Patent No. 4766385

[9] Body surface position locator for ultrasound transducer, US patent n° 5619999 [9] Body surface position locator for ultrasound transducer, US patent n ° 5619999

Claims

REVENDICATIONS 1) Le système émetteur - récepteur décrit un principe de localisation et d'identification d'objets à distance, sans contact, objets étant enfouis ou apparents. Le principe utilisé pour la détection est le «piézo-électro-magnétisme».1) The transmitter-receiver system describes a principle of localization and identification of objects at a distance, without contact, objects being buried or apparent. The principle used for detection is “piezo-electro-magnetism”. 2) L'émetteur est un système générant une impulsion sous forme d'une onde ou d'un train d'ondes acoustique.2) The transmitter is a system generating an impulse in the form of an acoustic wave or train of waves. 3) Le marqueur est un système constitué d'un élément piézo-électrique P, connecté à une antenne, via un éventuel dispositif de transfert T (élément non linéaire, puce électronique, dispositif de codage...).3) The marker is a system consisting of a piezoelectric element P, connected to an antenna, via a possible transfer device T (non-linear element, electronic chip, coding device, etc.). 4) Le dispositif de transfert T est un élément non linéaire, une puce électronique, un dispositif de codage.4) The transfer device T is a non-linear element, an electronic chip, a coding device. 5) L'élément piézo-électrique P est un matériau céramique façonné de manière à être accordé sur des fréquences caractéristiques. Il est capable de délivrer une impulsion électrique, corrélée à l'excitation acoustique, vers le circuit de transfert, puis vers l'antenne A.5) The piezoelectric element P is a ceramic material shaped so as to be tuned on characteristic frequencies. It is capable of delivering an electrical pulse, correlated to the acoustic excitation, to the transfer circuit, then to the antenna A. 6) L'antenne A est un dispositif conducteur (type inductance ou circuit RLC) capable de générer un champ magnétique corrélé au courant électrique délivré par le dispositif piézo-électrique / fonction de transfert.6) The antenna A is a conductive device (inductance or RLC circuit type) capable of generating a magnetic field correlated to the electric current delivered by the piezoelectric device / transfer function. 7) Le récepteur est constitué d'une antenne de réception adaptée à l'émission du marqueur, et connectée à un système de traitement du signal.7) The receiver consists of a reception antenna adapted to the transmission of the marker, and connected to a signal processing system. 8) Le récepteur est couplé à l'émetteur.8) The receiver is coupled to the transmitter. 9) Le traitement du signal permet d'analyser la forme du signal retour, les amplitudes et déphasages.9) Signal processing makes it possible to analyze the shape of the return signal, the amplitudes and phase shifts. 10)La détection est réalisée au travers de milieux solides homogènes ou hétérogènes, liquides et éventuellement gazeux.10) The detection is carried out through homogeneous or heterogeneous solid media, liquid and possibly gaseous. 11)Le caractère sélectif de la détection est assuré par une distribution ou association de marqueurs à caractères diversifiés (fréquence, fonction de transfert...). 12)L'association de marqueurs différents permet par mesure différentielle d'évaluer la distance entre l'émetteur et le marqueur.11) The selective nature of the detection is ensured by a distribution or association of markers with diversified characters (frequency, transfer function, etc.). 12) The association of different markers makes it possible by differential measurement to evaluate the distance between the transmitter and the marker. 13)Le système décrit précédemment permet la localisation et l'identification de tout objet auquel aura été associé un marqueur donné.13) The system described above allows the location and identification of any object with which a given marker has been associated. 14) Les applications potentielles.14) Potential applications. 15)A titre d'exemple, quelques applications : - localisation de câbles, de tuyaux et de structures enterrés ou enfouies ;15) As an example, some applications: - location of cables, pipes and buried or buried structures; - localisation de vêtements (avalanches, éboulements...) ;- location of clothing (avalanches, landslides, etc.); - détection de mines ;- mine detection; - détection de bornes de marquage (travaux publics) ;- detection of marking posts (public works); - codage de pièces détachées automobiles, avioniques, industrielles... - coding of automotive, avionics, industrial spare parts ...
PCT/FR1999/002665 1999-10-18 1999-10-27 System for electromagnetic detection and identification of objects by acoustic excitation Ceased WO2001029575A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR9913114A FR2799841A1 (en) 1999-10-18 1999-10-18 Contactless buried piezoelectric detection system has piezoelectric acoustic transmitter activating piezoelectric transfer module which returns the signal to be received and processed
FR99/13114 1999-10-18

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Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1990003070A1 (en) * 1988-09-16 1990-03-22 Universal Tracking Systems Ltd. A/S Identification system
US4935907A (en) * 1988-02-22 1990-06-19 Friedman Mark B Electronic homing system
JPH03233381A (en) * 1990-02-08 1991-10-17 Takeshi Ikeda Distance measuring system
WO1994005090A1 (en) * 1992-08-14 1994-03-03 Magellan Corporation (Australia) Pty. Ltd. Identification apparatus

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4935907A (en) * 1988-02-22 1990-06-19 Friedman Mark B Electronic homing system
WO1990003070A1 (en) * 1988-09-16 1990-03-22 Universal Tracking Systems Ltd. A/S Identification system
JPH03233381A (en) * 1990-02-08 1991-10-17 Takeshi Ikeda Distance measuring system
WO1994005090A1 (en) * 1992-08-14 1994-03-03 Magellan Corporation (Australia) Pty. Ltd. Identification apparatus

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
PATENT ABSTRACTS OF JAPAN vol. 016, no. 015 (P - 1298) 14 January 1992 (1992-01-14) *

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