WO1988007656A1 - Systeme a interferometres de detection de position - Google Patents

Systeme a interferometres de detection de position Download PDF

Info

Publication number
WO1988007656A1
WO1988007656A1 PCT/GB1988/000214 GB8800214W WO8807656A1 WO 1988007656 A1 WO1988007656 A1 WO 1988007656A1 GB 8800214 W GB8800214 W GB 8800214W WO 8807656 A1 WO8807656 A1 WO 8807656A1
Authority
WO
WIPO (PCT)
Prior art keywords
probe
interferometers
interferometer
retro
reflector
Prior art date
Application number
PCT/GB1988/000214
Other languages
English (en)
Inventor
David Roberts Mcmurtry
Original Assignee
Renishaw Plc
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Renishaw Plc filed Critical Renishaw Plc
Publication of WO1988007656A1 publication Critical patent/WO1988007656A1/fr

Links

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
    • G01B11/00—Measuring arrangements characterised by the use of optical techniques
    • G01B11/002—Measuring arrangements characterised by the use of optical techniques for measuring two or more coordinates
    • G01B11/005—Measuring arrangements characterised by the use of optical techniques for measuring two or more coordinates coordinate measuring machines

Definitions

  • This invention relat'es to interferometer systems for measuring the position of an object.
  • an interferometer system to locate the position of an object within a three dimensional co-ordinate reference system.
  • the object might be a workpiece-sensing probe mounted in the quill of a co-ordinate measuring machine, which can move in the three co-ordinate directions.
  • the quill or the probe carries a retroreflector, and a plurality of tracking interferometers are fixed relative to the base of the machine.
  • These interferometers each fire a laser beam which tracks the retroreflector and measure very precisely the distance from the interferometer to the retroreflector.
  • the precise X, Y and Z co-ordinates of the retroreflector can be deter ⁇ ined by trigonometry
  • the present invention provides an interferometer system for determining the position of an object, comprising:
  • a probe for sensing the object the probe being movable in three co-ordinate dimensions relative to a base upon which the object is moun-table; a plurality of retroreflectors mounted so as to be movable with the probe; a plurality of tracking interferometers each arranged to fire a beam at a said retroreflector, to receive a reflected beam back from the retroreflector and to measure the distance along the beam path between the interferometer and the retroreflector.
  • a useful improvement of the known system described above can be achieved by the use of two retroreflectors on the probe, and sufficient interferometers to determine their positions. This enables a determination to be made as to whether the probe is mounted in a tilted manner. Given a known relationship between the sensing tip of the probe and the retrore lectors (e.g. determined by datuming the probe against a reference surface) , the position in space of the sensing tip can be determined. This can be achieved using four tracking interferometers, two firing their beams at each retroreflector.
  • the sensing tip of the probe in space, it is preferred that there should be at least three retroreflectors mounted with the probe, with an appropriate number of interferometers to enable a determination of the position of each. If one can thus determine the location in space of three points associated with the probe, then its positio'n can be determined absolutely, even if the probe suffers misalignment in all six of its degrees of freedom (three degrees of translational freedom and three degrees of rotational freedom).
  • the co-ordinate measuring machine has a base 10 upon which may be placed a workpiece 12 to be measured.
  • a probe 14 is mounted in a quill (not shown) of the machine so as to be movable in +_X, +_Y and ⁇ 2, directions by conventional means.
  • the probe 14 has a stylus 16 with a stylus tip 18 for contacting the surfaces of the workpiece 12, and the probe 14 produces a signal on a line 20 to a machine control computer 22 when contact with the workpiece is detected, in known manner.
  • the computer 22 also controls movement of the probe in the X, Y, Z directions.
  • the machine is provided with an interferometer system 24, comprising six tracking laser interferometers, whose outputs are designated 30,31,32,33,34,35.
  • the interferometers are supplied from a common laser light source 26 via suitable beam splitters (not shown).
  • the probe 14 is provided with three corner cube retroreflectors 50, 51, 52, the function of which is to receive the laser beams from the interferometers and reflect them back whence they came.
  • Other forms of retroreflector are perfectly possible, for example cats eye retroreflectors.
  • each interferometer comprises a beam splitter which splits the laser beam in o a reference arm and a measurement arm.
  • the measurement arm of the beam is directed to one of the retroreflectors on the probe 14.
  • Each interferometer has a fringe detector, and a respective fringe counter 40, 41, 42, 43,44, 45 in which a count of the number of fringes passing the detector is kept. In this way, a count is kept of the distance from the respective interferometer to the corresponding retroreflector on the probe.
  • These distances are passed to a computer 60 which then determines the X, Y and Z co-ordinates of the probe by triangulation.
  • the computer 60 reads the instantaneous value of all of the counters 40 - 45, and performs a calculation to determine the X, Y, Z co-ordinates of the stylus tip 18, based upon the known separations of the interferometers and of the retroreflectors. These co-ordinates are passed to the machine control computer 22. In particular, the control computer 22 demands a calculation of these co-ordinates from the computer 60 based on the instantaneous values of the counters at the time the probe signal is received on line 20.
  • each interferometer can track the X, Y and Z movements of the probe 14
  • each of the outputs is via a servo-controlled gimballed mirror, which pivots under the servo control about two orthogonal axes.
  • This servo control is controlled by a quad detector which senses the return beam from the probe 14 and ensures that the laser beam tracks the probe.
  • quad detector which senses the return beam from the probe 14 and ensures that the laser beam tracks the probe.
  • Such servo-controlled tracking arrangements are known.
  • the three retroreflectors on the probe are not co-linear. Consequently, if the position of each of the three retroreflectors is determined, and if there is a constant relationship between the retroreflectors and the stylus tip 18, the position of the stylus tip 18 is thus uniquely determined.
  • each retroreflector 50, 51, 5 it would be possible for each retroreflector 50, 51, 5 to be associated with a pair of the interferometers. Knowing the respective distance from the interferomete to the retroflector indicated by each of the counters 40 - 45, and knowing the relative spacings of the interferometers and the relative spacings of the retrore lectors, the computer 60 has sufficient information to uniquely determine the position in spac of the stylus tip 18 (or more broadly, of a datum poin on the probe 14 having a fixed relationship with the stylus tip 18) .
  • interferometers rather than working the interferometers in such a 2-2-2 arrangement, with two interferometers for each retroreflector 50, 51, 52, it is possible to use them in a 3-2-1 arrangement. That is, three of the interferometers 32, 33, 34 track one retroreflector 50 another two interferometers 31, 35 track a second retroreflector 51, while the last retroreflector 52 is tracked by only one interferometer 30.
  • This arrangement permits full positional information to be determined by the computer 60, just as adequately as a 2-2-2 arrangement, and is preferable because the calculations performed by the computer 60 start from better conditioned matrices, and are therefore simpler.
  • Three retroreflectors and six interferometers is the minimum requirement for complete positional information about the probe.
  • some redundancy may be built into the system by providing one or more extra interferometers.
  • the advantage of such redundancy becomes apparent if one considers the case where one of the laser beams is broken during the course of a measurement. If there are no redundant interferometers, then upon the breaking of a beam, the corresponding counter 40 - 45 will lose count of the number of fringes which its corresponding interferometer has detected. Consequently, the output of that interferometer could no longer be relied upon.
  • the interferometer would lose track of its corresponding retroreflector.
  • the only solution when a beam is broken is to completely reset the system and commence the measurement again. This is a cumbersome operation.
  • a alternative is to scan the area, searching for the retrore lector, but this is also a cumbersome operation, particularly since one has to verify that one has locked onto the correct retroreflector.
  • the computer With 3-3-3 system with redundant interferometers, however, if any beam is broken, the computer still has sufficient information to know the absolute position of each retroreflector. It can therefore be arranged to control the servo-control mechanism of the interferometer with the broken beam, and to update the corresponding counter, until such time as the beam returns. That is to say, each beam can be recalibrate automatically when it returns after being broken, without interrupting the normal measurement operations of the machine.
  • a further type of redundancy which is possible is to provide more than three retroreflectors on the probe, each tracked by an appropriate number of interferometers.
  • the advantage of this is that it enables the computer 60 to keep track of the position of the probe even if one of the retroreflectors is taken behind the workpiece 12 during the course of a measurement, thus breaking all the beams which play on that retroreflector.
  • the embodiment described can be used on a machine tool desired, instead of on a co-ordinate measuring machine.

Landscapes

  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Length Measuring Devices By Optical Means (AREA)

Abstract

Un capteur (14) est mobile en trois dimensions pour détecter la position d'une pièce à travailler (12). Six interféromètres (30-35) de localisation projettent chacun un faisceau laser sur un des trois rétro-réflecteurs (50, 51, 52) associés au capteur et reçoivent ledit faisceau au retour. Un compteur de franges d'interférence (40-45) pour chaque interféromètre mesure la distance entre l'interféromètre respectif et le rétro-réflecteur correspondant. Trois interféromètres (32, 33, 34) sont associés au premier rétro-réflecteur (50), deux 31, 35) au second, et un (30) au troisième (52). L'ordinateur (60) reçoit ainsi suffisamment d'informations pour calculer de manière univoque la position dans l'espace d'une donnée de référence du capteur (14), quelle que soit la position et l'orientation du capteur.
PCT/GB1988/000214 1987-03-21 1988-03-21 Systeme a interferometres de detection de position WO1988007656A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
GB878706790A GB8706790D0 (en) 1987-03-21 1987-03-21 Interferometer position measurement system
GB8706790 1987-03-21

Publications (1)

Publication Number Publication Date
WO1988007656A1 true WO1988007656A1 (fr) 1988-10-06

Family

ID=10614417

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/GB1988/000214 WO1988007656A1 (fr) 1987-03-21 1988-03-21 Systeme a interferometres de detection de position

Country Status (2)

Country Link
GB (1) GB8706790D0 (fr)
WO (1) WO1988007656A1 (fr)

Cited By (20)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE4312579A1 (de) * 1993-04-17 1994-10-20 Matthias Schum Meßmaschine
DE4328533A1 (de) * 1993-08-25 1995-03-02 Matthias Schum Meßmaschine
WO1995014905A1 (fr) * 1993-11-25 1995-06-01 Renishaw Plc Dispositifs servant a mesurer des positions
GB2285550A (en) * 1994-01-05 1995-07-12 Creo Products Inc Optical coordinate measuring system for large objects
EP0754930A2 (fr) * 1995-07-20 1997-01-22 Bayerische Motoren Werke Aktiengesellschaft, Patentabteilung AJ-3 Dispositif pour le balayage des surfaces de mesure
WO1998057121A1 (fr) * 1997-06-12 1998-12-17 Werth Messtechnik Gmbh Appareil de mesure de coordonnees comportant un palpeur et detecteur optique mesurant la position de ce dernier
WO2001088470A1 (fr) * 2000-05-17 2001-11-22 Unisensor Aps Systeme de mesure et procede de mesure d'angles et de distances
EP1174679A2 (fr) * 2000-07-18 2002-01-23 Nikon Corporation Boitier pour interféromètre
WO2002027264A1 (fr) * 2000-09-28 2002-04-04 Carl Zeiss Appareil de mesure de coordonnees
WO2002066922A2 (fr) * 2001-02-20 2002-08-29 Max Bögl Bauunternehmung GmbH & Co. KG Procede pour mesurer et/ou usiner une piece
EP1251328A2 (fr) * 2001-04-13 2002-10-23 Carl Zeiss Système et procédé pour déterminer la position ou/et l'orientation de deux objets l'un part rapport à l'autre ainsi que appareil de guidage d'un faisceau, interféromètre et appareil pour modifier la longueur du trajet optique utilisé dans un tel système et procédé
DE10118668A1 (de) * 2001-04-14 2002-10-24 Schott Glas Koordinatenmeßvorrichtung
EP1510779A1 (fr) * 2003-08-29 2005-03-02 metronom AG Procédé pour déterminer des coordonnées de position
EP1541959A1 (fr) * 2003-12-09 2005-06-15 metronom AG Dispositif et procédé pour déterminer des ccordonnées de position
EP1672313A1 (fr) * 2004-12-20 2006-06-21 Steinbichler Optotechnik Gmbh Inspection automatique de pièces
WO2012028388A1 (fr) * 2010-08-30 2012-03-08 Carl Zeiss Ag Unité de mesure, système de mesure et procédé de détermination d'une position relative et d'une orientation relative
DE102015204796A1 (de) * 2015-03-17 2016-09-22 Carl Zeiss Industrielle Messtechnik Gmbh Koordinatenmessgerät mit beweglichem Sensorträger und Positionsbestimmungseinrichtung, sowie Verfahren zum Betreiben eines Koordinatenmessgeräts
DE102015205566A1 (de) * 2015-03-26 2016-09-29 Carl Zeiss Industrielle Messtechnik Gmbh Kalibrierung eines an einem beweglichen Teil eines Koordinatenmessgeräts angebrachten taktilen Tasters
DE102016113531A1 (de) * 2016-07-22 2018-01-25 Etalon Ag Messsystem zum Messen von Längen und/oder Längenänderungen
WO2020104666A1 (fr) * 2018-11-22 2020-05-28 Carl Zeiss Industrielle Messtechnik Gmbh Procédé et dispositif servant à définir au moins une position et une orientation spatiales et à orienter au moins un objet de mesure

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1981002627A1 (fr) * 1980-03-06 1981-09-17 Caterpillar Tractor Co Dispositif de determination de coordonnee
EP0144546A1 (fr) * 1983-09-23 1985-06-19 Firma Carl Zeiss Machine de mesure à plusieurs coordonnées
US4621926A (en) * 1985-04-30 1986-11-11 Lasercon Corporation Interferometer system for controlling non-rectilinear movement of an object

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1981002627A1 (fr) * 1980-03-06 1981-09-17 Caterpillar Tractor Co Dispositif de determination de coordonnee
EP0144546A1 (fr) * 1983-09-23 1985-06-19 Firma Carl Zeiss Machine de mesure à plusieurs coordonnées
US4621926A (en) * 1985-04-30 1986-11-11 Lasercon Corporation Interferometer system for controlling non-rectilinear movement of an object

Cited By (32)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE4312579A1 (de) * 1993-04-17 1994-10-20 Matthias Schum Meßmaschine
DE4328533A1 (de) * 1993-08-25 1995-03-02 Matthias Schum Meßmaschine
US5604593A (en) * 1993-11-25 1997-02-18 Renishaw Plc Interferometer position measurement system with extensible legs
WO1995014905A1 (fr) * 1993-11-25 1995-06-01 Renishaw Plc Dispositifs servant a mesurer des positions
GB2285550A (en) * 1994-01-05 1995-07-12 Creo Products Inc Optical coordinate measuring system for large objects
GB2285550B (en) * 1994-01-05 1997-09-17 Creo Products Inc Optical coordinate measuring system for large objects
EP0754930A3 (fr) * 1995-07-20 1997-12-17 Bayerische Motoren Werke Aktiengesellschaft, Patentabteilung AJ-3 Dispositif pour le balayage des surfaces de mesure
DE19526526A1 (de) * 1995-07-20 1997-01-23 Bayerische Motoren Werke Ag Vorrichtung zum optischen Abtasten von Meßflächen
EP0754930A2 (fr) * 1995-07-20 1997-01-22 Bayerische Motoren Werke Aktiengesellschaft, Patentabteilung AJ-3 Dispositif pour le balayage des surfaces de mesure
WO1998057121A1 (fr) * 1997-06-12 1998-12-17 Werth Messtechnik Gmbh Appareil de mesure de coordonnees comportant un palpeur et detecteur optique mesurant la position de ce dernier
WO2001088470A1 (fr) * 2000-05-17 2001-11-22 Unisensor Aps Systeme de mesure et procede de mesure d'angles et de distances
EP1174679A2 (fr) * 2000-07-18 2002-01-23 Nikon Corporation Boitier pour interféromètre
EP1174679A3 (fr) * 2000-07-18 2003-03-12 Nikon Corporation Boitier pour interféromètre
WO2002027264A1 (fr) * 2000-09-28 2002-04-04 Carl Zeiss Appareil de mesure de coordonnees
WO2002066922A2 (fr) * 2001-02-20 2002-08-29 Max Bögl Bauunternehmung GmbH & Co. KG Procede pour mesurer et/ou usiner une piece
WO2002066922A3 (fr) * 2001-02-20 2003-12-04 Boegl Max Bauunternehmung Gmbh Procede pour mesurer et/ou usiner une piece
DE10118392A1 (de) * 2001-04-13 2002-11-07 Zeiss Carl System und Verfahren zum Bestimmen einer Position oder/und Orientierung zweier Objekte relativ zueinander sowie Strahlführungsanordnung, Interferometeranordnung und Vorrichtung zum Ändern einer optischen Weglänge zum Einsatz in einem solchen System und Verfahren
US7358516B2 (en) 2001-04-13 2008-04-15 Carl Zeiss Ag System and method for determining a position or/and orientation of two objects relative to each other as well as beam guiding arrangement, interferometer arrangement and device for changing an optical path length for use in such a system and method
EP1251328A2 (fr) * 2001-04-13 2002-10-23 Carl Zeiss Système et procédé pour déterminer la position ou/et l'orientation de deux objets l'un part rapport à l'autre ainsi que appareil de guidage d'un faisceau, interféromètre et appareil pour modifier la longueur du trajet optique utilisé dans un tel système et procédé
EP1251328A3 (fr) * 2001-04-13 2002-11-27 Carl Zeiss Système et procédé pour déterminer la position ou/et l'orientation de deux objets l'un part rapport à l'autre ainsi que appareil de guidage d'un faisceau, interféromètre et appareil pour modifier la longueur du trajet optique utilisé dans un tel système et procédé
DE10118668A1 (de) * 2001-04-14 2002-10-24 Schott Glas Koordinatenmeßvorrichtung
DE10118668B4 (de) * 2001-04-14 2004-02-05 Schott Glas Koordinatenmeßvorrichtung
EP1510779A1 (fr) * 2003-08-29 2005-03-02 metronom AG Procédé pour déterminer des coordonnées de position
EP1541959A1 (fr) * 2003-12-09 2005-06-15 metronom AG Dispositif et procédé pour déterminer des ccordonnées de position
EP1672313A1 (fr) * 2004-12-20 2006-06-21 Steinbichler Optotechnik Gmbh Inspection automatique de pièces
WO2012028388A1 (fr) * 2010-08-30 2012-03-08 Carl Zeiss Ag Unité de mesure, système de mesure et procédé de détermination d'une position relative et d'une orientation relative
US9329027B2 (en) 2010-08-30 2016-05-03 Carl Zeiss Ag Measuring unit, measuring system and method for determining a relative position and relative orientation
DE102015204796A1 (de) * 2015-03-17 2016-09-22 Carl Zeiss Industrielle Messtechnik Gmbh Koordinatenmessgerät mit beweglichem Sensorträger und Positionsbestimmungseinrichtung, sowie Verfahren zum Betreiben eines Koordinatenmessgeräts
DE102015205566A1 (de) * 2015-03-26 2016-09-29 Carl Zeiss Industrielle Messtechnik Gmbh Kalibrierung eines an einem beweglichen Teil eines Koordinatenmessgeräts angebrachten taktilen Tasters
DE102015205566B4 (de) 2015-03-26 2020-01-23 Carl Zeiss Industrielle Messtechnik Gmbh Kalibrierung eines an einem beweglichen Teil eines Koordinatenmessgeräts angebrachten taktilen Tasters
DE102016113531A1 (de) * 2016-07-22 2018-01-25 Etalon Ag Messsystem zum Messen von Längen und/oder Längenänderungen
WO2020104666A1 (fr) * 2018-11-22 2020-05-28 Carl Zeiss Industrielle Messtechnik Gmbh Procédé et dispositif servant à définir au moins une position et une orientation spatiales et à orienter au moins un objet de mesure

Also Published As

Publication number Publication date
GB8706790D0 (en) 1987-04-23

Similar Documents

Publication Publication Date Title
WO1988007656A1 (fr) Systeme a interferometres de detection de position
US6870605B2 (en) Method of measuring length and coordinates using laser tracking interferometric length measuring instruments
CA1186893A (fr) Systeme de metrologie a coordonnees ponctuelles pour polygones
US4691446A (en) Three-dimensional position measuring apparatus
US7285793B2 (en) Coordinate tracking system, apparatus and method of use
Fan et al. A six-degree-of-freedom measurement system for the motion accuracy of linear stages
US5076690A (en) Computer aided positioning system and method
US5267014A (en) Position and orientation measurement device
US4663852A (en) Active error compensation in a coordinated measuring machine
US4261107A (en) Coordinate locating device
Takatsuji et al. The relationship between the measurement error and the arrangement of laser trackers in laser trilateration
US4892407A (en) Optical measuring apparatus for use on machines
JP2579226B2 (ja) 干渉測定装置用光学装置
JPH01502530A (ja) 位置決定装置
GB1254911A (en) Method and apparatus for interferometric measurement
US4714344A (en) Laser apparatus for monitoring geometric errors
US4538911A (en) Three-dimensional interferometric length-measuring apparatus
EP1509747B1 (fr) Systeme de metrologie pour deplacement 3d de precision
US10473451B2 (en) Measuring the position of objects in space
GB2170005A (en) Interferometric multicoordinate measuring device
JP3394972B2 (ja) 自動工作機械
JP2795613B2 (ja) 移動体の位置及び姿勢の測定方法
GB2069169A (en) Measuring apparatus and method for determining the three- dimensional position of a body
Osawa et al. Evaluation of the performance of a novel laser tracker used for coordinate measurements
JPS6363904A (ja) 材料の加工及び測定用の装置

Legal Events

Date Code Title Description
AK Designated states

Kind code of ref document: A1

Designated state(s): JP US

AL Designated countries for regional patents

Kind code of ref document: A1

Designated state(s): AT BE CH DE FR GB IT LU NL SE