FR2553878A1 - Optical position-referencing system - Google Patents
Optical position-referencing system Download PDFInfo
- Publication number
- FR2553878A1 FR2553878A1 FR8316949A FR8316949A FR2553878A1 FR 2553878 A1 FR2553878 A1 FR 2553878A1 FR 8316949 A FR8316949 A FR 8316949A FR 8316949 A FR8316949 A FR 8316949A FR 2553878 A1 FR2553878 A1 FR 2553878A1
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- Prior art keywords
- fiber
- sensor
- receiving
- optical
- wavelength
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- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
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- 230000003287 optical effect Effects 0.000 title claims description 15
- 239000000835 fiber Substances 0.000 claims abstract description 25
- 239000013307 optical fiber Substances 0.000 claims abstract description 13
- 238000005259 measurement Methods 0.000 claims abstract description 3
- 230000005540 biological transmission Effects 0.000 claims description 7
- 230000010365 information processing Effects 0.000 claims description 2
- CBENFWSGALASAD-UHFFFAOYSA-N Ozone Chemical compound [O-][O+]=O CBENFWSGALASAD-UHFFFAOYSA-N 0.000 claims 1
- 101100502609 Caenorhabditis elegans fem-1 gene Proteins 0.000 description 3
- 101100334582 Drosophila melanogaster Fem-1 gene Proteins 0.000 description 3
- 238000010586 diagram Methods 0.000 description 3
- 238000003491 array Methods 0.000 description 1
- 239000006185 dispersion Substances 0.000 description 1
- 238000006073 displacement reaction Methods 0.000 description 1
- 238000007493 shaping process Methods 0.000 description 1
- 238000011144 upstream manufacturing Methods 0.000 description 1
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01D—MEASURING NOT SPECIALLY ADAPTED FOR A SPECIFIC VARIABLE; ARRANGEMENTS FOR MEASURING TWO OR MORE VARIABLES NOT COVERED IN A SINGLE OTHER SUBCLASS; TARIFF METERING APPARATUS; MEASURING OR TESTING NOT OTHERWISE PROVIDED FOR
- G01D5/00—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable
- G01D5/26—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable characterised by optical transfer means, i.e. using infrared, visible, or ultraviolet light
- G01D5/32—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable characterised by optical transfer means, i.e. using infrared, visible, or ultraviolet light with attenuation or whole or partial obturation of beams of light
- G01D5/34—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable characterised by optical transfer means, i.e. using infrared, visible, or ultraviolet light with attenuation or whole or partial obturation of beams of light the beams of light being detected by photocells
- G01D5/347—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable characterised by optical transfer means, i.e. using infrared, visible, or ultraviolet light with attenuation or whole or partial obturation of beams of light the beams of light being detected by photocells using displacement encoding scales
- G01D5/34707—Scales; Discs, e.g. fixation, fabrication, compensation
- G01D5/34715—Scale reading or illumination devices
- G01D5/34723—Scale reading or illumination devices involving light-guides
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01D—MEASURING NOT SPECIALLY ADAPTED FOR A SPECIFIC VARIABLE; ARRANGEMENTS FOR MEASURING TWO OR MORE VARIABLES NOT COVERED IN A SINGLE OTHER SUBCLASS; TARIFF METERING APPARATUS; MEASURING OR TESTING NOT OTHERWISE PROVIDED FOR
- G01D5/00—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable
- G01D5/26—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable characterised by optical transfer means, i.e. using infrared, visible, or ultraviolet light
- G01D5/268—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable characterised by optical transfer means, i.e. using infrared, visible, or ultraviolet light using optical fibres
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Arrangements For Transmission Of Measured Signals (AREA)
Abstract
Description
La présente invention concerne les systèmes de repèrage de @@@ @@@@ @@@@@@ par exemple en mouvement dans l'es
@@@ de façon @@@@@ optique. The present invention relates to the tracking systems of @@@ @@@@ @@@@@@ for example in motion in the es
@@@ optically @@@@@.
La présente invention s'applique tout particulièrement aux gouvernes pour l'aéronautique, la marine, etc... The present invention applies very particularly to control surfaces for aeronautics, the navy, etc.
Des systèmes de repérage de la position d'un mobile sont déjà connus. Ils consistent à disposer un capteur sur le mobile à repérer et à transmettre les informations reçues vers un calculateur d'exploitation des résultats. La plupart des systèmes connus supposent un apport d'énergie électrique et sont donc sensibles aux interférences radio électriques et aux impulsions électromagnétiques. Systems for locating the position of a mobile are already known. They consist of placing a sensor on the mobile to locate and transmit the information received to a computer for processing the results. Most known systems assume an electrical energy supply and are therefore sensitive to radio interference and electromagnetic pulses.
La présente invention vise à s'affranchir de tous ces inconvénients en-proposant un système entièrement passif et numérique. De plus, le système est particulièrement économi- que en nombre de composants. The present invention aims to overcome all these drawbacks by proposing an entirely passive and digital system. In addition, the system is particularly economical in terms of number of components.
La présente invention s'applique à tout déplacement, aussi bien angulaire que linéaire. The present invention applies to any displacement, both angular and linear.
Le système de repérage de l'invention consiste essentiellement à disposer des moyens optiques pour relier l'entrée et la sortie d'au moins un capteur de mesure, lesdits moyens optiques étant formés d'une seule fibre optique émission et d'une seule fibre optique réception par capteur, lesdites fibres étant reliées à la grille codeuse de chaque capteur par l'intermédiaire d'un dispcsitif purement optique dispersif et focalisateur. ledit dispositif dispersif séparant le faisceau lumineux transmis par chaque fibre (émission ou réception) en fonction de leur longueur d'onde, ledit dispositif de focalisation focalisant chaque faisceau de longueur d'onde donnée en un point déterminé de la grille codeuse de chaque capteur. The tracking system of the invention essentially consists of having optical means for connecting the input and the output of at least one measurement sensor, said optical means being formed from a single emission optical fiber and from a single fiber. optical reception by sensor, said fibers being connected to the coding grid of each sensor by means of a purely optical dispersive and focusing device. said dispersive device separating the light beam transmitted by each fiber (emission or reception) according to their wavelength, said focusing device focusing each beam of given wavelength at a determined point on the coding grid of each sensor.
Selon une première caractéristique, chaque longueur d'onde transporte un élément binaire d'information. According to a first characteristic, each wavelength carries a binary element of information.
Selon une autre caractéristique, les éléments binaires sont multiplexés temporellement et transmis en série sur une même fibre optique aussi bien à l'émission qu'à la réception. According to another characteristic, the binary elements are time multiplexed and transmitted in series on the same optical fiber both at transmission and at reception.
Selon une autre caractéristique, chaque secteur de la roue codeuse transforme l'état binaire porté par le faisceau de longueur d'onde qui lui est attribué selon l'information à transmettre. According to another characteristic, each sector of the coding wheel transforms the binary state carried by the wavelength beam which is allocated to it according to the information to be transmitted.
Selon une autre caractéristique, p capteurs sont reliés chacun au moyen d'une fibre émettrice et d'une fibre réceptrice, chaque fibre émettrice recevant une multitude de signaux numériques fournis par une tête optique émission, chaque fibre réceptrice transmettant son signal numérique à l'entrée d'une photodiode d'un dispositif récepteur, ledit dispositif récepteur étant lui-même relié à un dispositif de traitement de l'information. According to another characteristic, p sensors are each connected by means of a transmitting fiber and a receiving fiber, each transmitting fiber receiving a multitude of digital signals supplied by a transmitting optical head, each receiving fiber transmitting its digital signal to the input of a photodiode of a receiving device, said receiving device itself being connected to an information processing device.
D'autres avantages et caractér stiques appareltront: à la lecture de la description suivante illustrée par des dessins. Other advantages and features will become apparent on reading the following description illustrated by drawings.
La figure 1 représente une réalisation d'un capteur pour le système de repérage de l'invention. Figure 1 shows an embodiment of a sensor for the tracking system of the invention.
La figure 2 représente un schéma général du système de repérage de l'invention. FIG. 2 represents a general diagram of the tracking system of the invention.
La figure 3 représente un diagramme des temps des signaux numériques émis en ligne. FIG. 3 represents a time diagram of the digital signals transmitted online.
Des capteurs de position sont déjà connus. Ils consistent essentiellement en une grille codeuse divisée en secteurs, chaque secteur correspondant à une position bien déterminée. Position sensors are already known. They essentially consist of a coding grid divided into sectors, each sector corresponding to a well-defined position.
Cette grille codeuse est solidaire du mobile dont on souhaite repérer la position. La figure 1 désigne par G une telle grille codeuse. On raccorde selon l'invention une telle grille G1 du capteur C1 de l'invention au moyen d'une même fibre optique
Fem1 émission et d'une même fibre optique réception Fri. En effet, la fibre optique émission Fermi transmet les longueurs d'onde ...i devant les secteurs convenablement choisis 12 n de la grille G1.A cet effet, on interpose entre la fibre émission Fem1 et la grille G1 un dispositif optique Pem dispersif et focalisateur permettant, d'une part, de disperser la lumière transmise par la fibre Fem1 en fonction de sa longueur d'onde propre, d'autre part, de focaliser chacun de ces faisceaux monochromatiques sur le secteur approprié de la grille codeuse G1. Un tel dispositif optique Pem est aisément réalisable par tout homme de métier. En sortie de la grille codeuse G1 , on dispose le dispositif optique inverse qui effectue la focalisation et la transmission sur une même fibre optique Fr1 réception de ces différents signaux.This coding grid is integral with the mobile of which it is desired to identify the position. FIG. 1 designates by G such a coding grid. According to the invention, such a grid G1 of the sensor C1 of the invention is connected by means of the same optical fiber.
Fem1 transmission and same fiber optic reception Fri. Indeed, the Fermi emission optical fiber transmits the wavelengths ... i in front of the suitably chosen sectors 12 n of the grid G1. For this purpose, an optical device Pem dispersive is interposed between the emission fiber Fem1 and the grid G1 and focusing allowing, on the one hand, to disperse the light transmitted by the fiber Fem1 according to its own wavelength, on the other hand, to focus each of these monochromatic beams on the appropriate sector of the coding grid G1. Such a Pem optical device can be easily produced by any person skilled in the art. At the output of the coding grid G1, there is the reverse optical device which performs the focusing and the transmission on the same optical fiber Fr1 receiving these different signals.
La figure 2 représente le mode d'exploitation d'un tel capteur C1 en amont et en aval. Les différentes longueurs d'onde sont générées par une tête optique émission 1 formée, soit, d'un laser multiaccordable, soit, d'un nombre n de lasers. Dans ce dernier cas, chaque laser émet un signal optique numérique, c'est à dire une impulsion qui est un "un" binaire. FIG. 2 represents the operating mode of such a sensor C1 upstream and downstream. The different wavelengths are generated by an emission optical head 1 formed either of a multi-tunable laser or of a number n of lasers. In the latter case, each laser emits a digital optical signal, ie a pulse which is a binary "one".
Un signal d'horloge fourni par le dispositif électronique de commande 2 répartit régulièrement dans le temps l'impulsion fournie par chaque laser. Ainsi, en se référant au diagramme des temps de la figure 3, le laser ( ) fournit le premier son "un" binaire, puis décalé de ft le second laser ( ) et ainsi de suite sachant qu'une période d'horloge est divisée de fa çon appropriée, par exemple en n temps t égaux. Un coupleur 11, disposé en sortie de ces lasers, couple de façon connue en soi les différents signaux numériques émis par ces n lasers pour les transmettre tous sur p fibres optiques.A clock signal supplied by the electronic control device 2 regularly distributes the pulse supplied by each laser over time. Thus, with reference to the time diagram in FIG. 3, the laser () provides the first sound "a" binary, then shifted by ft the second laser () and so on knowing that a clock period is divided appropriately, for example in n equal times. A coupler 11, disposed at the output of these lasers, couples in a manner known per se the various digital signals emitted by these n lasers to transmit them all over p optical fibers.
En effet, si p capteurs Cj sont utiles pour le repérage, on raccorde chacun de ces p capteurs à l'aide d'une fibre émission. Ainsi, le capteur Cj de la figure 1 est relié au coupleur 11 du dispositif 1 grâce à la fibre Femj. On comprend aisément que la grille codeuse G. du capteur C. reçoit alors
J - J en série les différentes longueurs d'onde, chaque longueur d'onde étant alors reçue sur le secteur approprié de cette grille Gj. En retour, la grille codeuse G. interrompt le fais
J J ceau lumineux de certaines longueurs d'onde (correspondant à un état binaire de l'intervalle de temps qui est attribué à cette longueur d'onde) ce qui modifie l'état binaire de ce signal.Cette grille codeuse G renvoie les faisceaux des au j tres longueurs d onde (qui se trouvent dans l'autre état binaire) vers la fibre réceptrice Fr. par l'intermédiaire du dispositif de dispersion et focalisation Pr comme décrit à l'aide de la figure 1. Chacune des p fibres de réception Frj sont recues sur un dispositif détecteur 3. Ce dispositif 3 de reception peut, par exemple, être formé de barrettes de p photodiodes comme il est bien connu de l'homme de métier (à chaque capteur, on fait alors correspondre une photodiode).In fact, if p sensors Cj are useful for locating, each of these p sensors is connected using an emission fiber. Thus, the sensor Cj in FIG. 1 is connected to the coupler 11 of the device 1 thanks to the fiber Femj. It is easy to understand that the coding grid G. of the sensor C. then receives
J - J serially the different wavelengths, each wavelength then being received on the appropriate sector of this grid Gj. In return, the coding grid G. interrupts the doing
JJ light beam of certain wavelengths (corresponding to a binary state of the time interval which is assigned to this wavelength) which modifies the binary state of this signal. This coding grid G returns the beams of the at j very wavelengths (which are in the other binary state) towards the receiving fiber Fr. by means of the dispersion and focusing device Pr as described with the aid of FIG. 1. Each of the p fibers of reception Frj are received on a detector device 3. This reception device 3 can, for example, be formed of arrays of p photodiodes as is well known to those skilled in the art (a photodiode is then matched to each sensor) .
On notera qu'il peut être avantageux de réunir les p fibres optiques émission Fem. sur un même câble à fibres opti J ques et de raccorder chaque capteur C. à la fibre qui lui est
J attribuée grâce à des dérivateurs Dem . En réception, il est de même avantageux de regrouper les p fibres optiques récep tion F sur un même câble, un dérivateur Dr. raccordant cha J J que capteur à la fibre du câble qui lui est affectée. Les fibres réceptrices Fr. transmettent donc en série les informations numériques codées par chaque capteur vers le dispositif 3 de réception. Il suffit alors de transmettre les informations détectées par les p photodiodes du dispositif récepteur 3 vers un dispositif électronique 4 de mise en forme des informations numériques qui sont ensuite appliquées à l'entrée d'un calculateur 5.It will be noted that it may be advantageous to combine the p fem emission optical fibers. on the same optic fiber cable and connect each sensor C. to the fiber it has
J assigned thanks to Dem. In reception, it is also advantageous to group the p receiving optical fibers F on the same cable, a Dr. tap-off connecting each JJ sensor to the fiber of the cable assigned to it. The receiving fibers Fr. therefore transmit the digital information coded by each sensor in series to the receiving device 3. It then suffices to transmit the information detected by the p photodiodes of the receiving device 3 to an electronic device 4 for shaping the digital information which is then applied to the input of a computer 5.
De tels systèmes d'exploitation des résultats sont à la portée de l'homme de l'art et ne serort pas plus avant explicités. Such results processing systems are within the reach of those skilled in the art and will not be explained further.
Un tel système permet. le repérage de -la position d'une gouverne. Ainsi, lorsqu'il s'agit d'un avion, les capteurs C. Such a system allows. the location of the position of a control surface. Thus, when it is an airplane, the C sensors.
J peuvent être placés sur les ailes de l'avion, les boîtiers 1, 2, 3, 4, 5 se trouvant dans la carlingue. Le système del'invention permet ainsi la transmission purement optique et numérique des informations. J can be placed on the wings of the aircraft, the boxes 1, 2, 3, 4, 5 being in the cabin. The inventive system thus allows purely optical and digital transmission of information.
Un tel système serait également applicable à tout traitement d'informations numériques fournies par divers appareils de mesure. Such a system would also be applicable to any processing of digital information supplied by various measuring devices.
Claims (5)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| FR8316949A FR2553878B1 (en) | 1983-10-25 | 1983-10-25 | OPTICAL POSITION MARKING SYSTEM |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| FR8316949A FR2553878B1 (en) | 1983-10-25 | 1983-10-25 | OPTICAL POSITION MARKING SYSTEM |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| FR2553878A1 true FR2553878A1 (en) | 1985-04-26 |
| FR2553878B1 FR2553878B1 (en) | 1987-04-17 |
Family
ID=9293472
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| FR8316949A Expired FR2553878B1 (en) | 1983-10-25 | 1983-10-25 | OPTICAL POSITION MARKING SYSTEM |
Country Status (1)
| Country | Link |
|---|---|
| FR (1) | FR2553878B1 (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0214845A2 (en) * | 1985-09-06 | 1987-03-18 | The University Of Liverpool | Device and method for determining displacement |
| WO1987005691A2 (en) * | 1986-03-13 | 1987-09-24 | Bertin & Cie | Remote opto-electronic detection device for detecting a physical magnitude |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4117460A (en) * | 1976-11-01 | 1978-09-26 | United Technologies Corporation | Sensing device |
| GB2054995A (en) * | 1979-07-14 | 1981-02-18 | Marconi Co Ltd | Optical position encoder arrangement |
| EP0034107A1 (en) * | 1980-02-11 | 1981-08-19 | United Technologies Corporation | Optical encoder using time domain multi-plexer |
-
1983
- 1983-10-25 FR FR8316949A patent/FR2553878B1/en not_active Expired
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4117460A (en) * | 1976-11-01 | 1978-09-26 | United Technologies Corporation | Sensing device |
| GB2054995A (en) * | 1979-07-14 | 1981-02-18 | Marconi Co Ltd | Optical position encoder arrangement |
| EP0034107A1 (en) * | 1980-02-11 | 1981-08-19 | United Technologies Corporation | Optical encoder using time domain multi-plexer |
Cited By (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0214845A2 (en) * | 1985-09-06 | 1987-03-18 | The University Of Liverpool | Device and method for determining displacement |
| EP0214845A3 (en) * | 1985-09-06 | 1989-03-01 | The University Of Liverpool | Device and method for determining displacement |
| WO1987005691A2 (en) * | 1986-03-13 | 1987-09-24 | Bertin & Cie | Remote opto-electronic detection device for detecting a physical magnitude |
| WO1987005692A2 (en) * | 1986-03-13 | 1987-09-24 | Bertin & Cie | Remote opto-electronic detection device and method for the detection of physical magnitudes |
| EP0241332A2 (en) * | 1986-03-13 | 1987-10-14 | Bertin & Cie | Opto-electronic device to detect a physical quantity at a distance |
| EP0242250A2 (en) * | 1986-03-13 | 1987-10-21 | Bertin & Cie | Opto-electronic device to detect a physical quantity at a distance |
| WO1987005692A3 (en) * | 1986-03-13 | 1988-04-21 | Bertin & Cie | Remote opto-electronic detection device and method for the detection of physical magnitudes |
| WO1987005691A3 (en) * | 1986-03-13 | 1988-04-21 | Bertin & Cie | Remote opto-electronic detection device for detecting a physical magnitude |
| EP0241332A3 (en) * | 1986-03-13 | 1988-06-08 | Bertin & Cie | Opto-electronic device to detect a physical quantity at a distance |
| EP0242250A3 (en) * | 1986-03-13 | 1988-06-15 | Bertin & Cie | Opto-electronic device to detect a physical quantity at a distance |
Also Published As
| Publication number | Publication date |
|---|---|
| FR2553878B1 (en) | 1987-04-17 |
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