SE1550114A1 - Milking arrangement - Google Patents

Description

2G 30 WO Ettíå/Ol-ßíiåi PCTiNL2013/O5G1-i8í speokied besm, a osrrtara for repsatsdiy ribtairiing an iiriags of a rsflscted part of said isssin, and a control unit arranged to form s threedirnensionsl image ironi said intogs by coinparirig said intogs with at least one reference reflection image of said nanm and taken with said ciamara, and ststistically oross~oorreiating said snackis pattern in said image with said sosokie pattern in said st least one reference reflection image, whereiit the control unit is itinher arranged to identify said tsats and to detect the iooation thereof with respect to the camera, on the basis of said three* dirneiwsional irnage_ in such a milkirig arrangsrnsnt, and such a control means, it ttrrns out to be possible to deteot tests, end thus connect the test oups, reiiabiy and fast. ln tuartioiiiar a fast detection is advaniageous as rniiking animals are live orsattires, that can inove in an iinpreciiotsbie way, hindsring easy detection and connection. 'l"liersfora, ii that detection is rieriorined swiftiy, connection becomes more reliable.

Special sinhodiihonis of the inventioii ars described in the dependent oisirns, ss well as in what follows. it is noied that the technology of creating a snackis pattern such as caused hy interfereitco among different components of a ditfused baarn, and to use the speokla pattern to estabiish position, orientaiion and/or movement is itself known from ao. the gainebox controller Kineot and their software developers Printeâšense, see ag. httrxI/www .j oystiqtzorn-/Zïii 0/061191kinect~how-it-worksßiro:nåtts-coinparty-behind» ihe-toohí. Theretora, for specific teohniosi details reference is :nade to corresponding publications such as WOZGQY/Ofiâtiišö. in the tvreserit appiicatiori, the presence of a inemory for one or more referenoe images of tiie speokles at' known distanoss, and other parts iiecessary to perform the method from the cited WOTBES document are dsemsd impiioitiy include-d in the rniiking arrangement, in particular in the control means. Heroin, various steps regarding the oross-oorreiatioii of an image to a ' reference image are given in an exempiary embodiment on pages 15 and further, liereby included by reference. i lt is furthermora rioted that detection of Structures and objects in a three~dimsnsioriai image is also known in the an. Depending on the objects to be detected, a ntimoer of criteria may be applied to the image. For example, if a test has to be dsteoted, one U! 10 2D 3G WG 281 åi/'Û 14341 TI NLliii åfflåflsi-Sl con took for s irioro or loss cylindrical object with a oiarnætor of .shout 2~3 om sno s length rooghiy between 2 sno 8- om, with s rounciso tio to this lowor side sno oonnootod st the Lippsr side to a much higgor splioricai structure, and niorsover being provided in fourfold in s trapszoiciai syrnmotry. Furthornicurs, ss finger dsisctioiw iiss sirssoy bssn contompiatsd for Kinoct sno such iiko syststns with only connputing power dotortniriing the roouirod rosotutioit, and as tests and fingers are goorriotrioslly like objects, the prssonily contoinplatsd systoin is woli suitool for test detection. Of ooorso, if other oojoots hood to os dstectscl, suitable; criteria can ho provided, based on knowledge of the ooornotry of those tvi-aiscts. ln advantage-ratas emoociimonts, the control uriit is furthor srrsngod to rietsct at toast one oi said foot cups and the position thorooi with respect to the itsinsra, on the basis of said tiiror-æciirriorisionai intogs. By not only idsntifyihg a toat and dotocting its location, but also ootocting tiio position of a tost cup in the image. the control unit csn determine the rnutuai distance oottvoon the toot cup and the test to which ii is to be connootsdr By oontroiiing the guiding of the test cup by ininiinising that distance, the efficiency wiil bo improved, lt siso snsuros that any mispositioning of the test cup on the robot arm con ho oorroctsci, Fsiiirig to do so and tislng only a lossio position rnigiit cause urisuooossful attempts to corinoct, which docresses system efficiency, A partictiiar advantage of the systsrn with rospoot to for example-e trisnguistion systems, using two or more Cameras, is that s single camera suffices to do measurements. An actual image by the camera is oornpsrsd and crosscorroiotsd with a storeo roisrsrico intogs takten before by the same camera ot s knovvn distance.

This makes the system loss vulnsratnio to inalfunctions of s camera (ss it has only one), but aiso faster, as oniy one image si a timo has to ho acquired. This increased spoed helps in ohtaining the incrsassd ootsction speed, in particuiar for unprooictahiy nioviiwg animals. Furthermore, ii also iiolos inst, contrsry to timo«of~ flight inossuromr-znts, no sampling of s moduiatod signal is necessary for each pixel scpsrateiy, nor integration of said signai for avsraging, to increase baoi signai-tc» noiso ratios. insvitahly, this takes time, whilo the arrsngoinont according to the invention only requires the grsbbing ot' a single image to doteot rnomentary position, since the processing can he ciono oxtornaily, with o high-power coinputer, that dose thus not hood tribe oro-sent very itoar the oamors or ovon on the robot arm. 10 15 20 25 30 WG 2014/81-'8341 .PCTÅNLZÜI 31050481 Thsretore, in a particular einbociiinent, the control nteans has a single oarriera that is arranged to reneatedly obtain an image of a refleoted part ot said heam from rrhich image the control unit fornis a thrse-dimsnsioriai image. it is stressad here that this single oarnera relates to the gratibing of the iiriage for iriaking the three~diinensional image, Other hanteras may be present for other purposes. “the torrning ot' the three diinsnsionai image stiil takes place hy cross-oorrelatinig the apeokle pattern in it with the speskle pattern of one or more reference images, as stored in the controi means.

Advantagsousiy, the specitle pattern generator' is arranged to generets a oonatant and random speckled pattern. 'This allow easlar' oross~correiation of the image with the reference image, as each part of the pattern is in principle unique, and can be traæcl in the ciistorted received image rnors easily. Howsver, it is also possible to use a speokie pattern generator that is arranged to ganerate a speckle pattern having some degree of regularity, up to a sompieteiy regular çnattsrn. in srnhodiments, the milking airangement according to the inveriticin further cornprises sin additionai sensor different from said camera, said sensor being arranged to obtain at least one additienai image of a reflssted part ot said lseam in a way that ditters from the way of said camera, and wherein the control unit is arranged to use said aciditionai image in identify/ing at least said teats. With such embodiments, an additional image is avaiiable' to improve the detection capabilities of the control means. Because in Lise, the ttetetztirsn of teats wili often depend on eg. edge detection and the like. But xwhen a surface is iriolined sharply, the refiected speckie pattern wiil be iocaliy weak andtor much distorted, lt is then relativeiy difficult to determine whether tiis- signal is just weak but real, or whether there is some note or other signai clisturbaitce. in other words, niany iiiteiihood criteria used to detect edges and the liite will have difticulties deterrnining such edges with a high acsuracy.

Now, by using an additionai image, this acouraoy artd iikelitiood may be improved, because it becomes better pcissibie to cieterrnirie wilethsr a structure in the acquired image is a real edge or similar structure by comparing it with the correspondingw part ot the additionai image. if the iatter tor example shows a similar disoontinuity, the likeiihood of there being a reai edge is higher, while a Smooth stirface in the additional image heips to oonoluds that there is not. 1G 15 20 30 Vi! 0 liiifliíiiïášál PCT/NLZOI 31050481 '-14 in smbooimonts, the additional sensor oornprises a therrnal image centern or en iiitresoiind sensor. Generaliy, such sensors ars loss susoootihls to din, es a layer of dirt wiil often sstili retisct ulirasound in rnusii the serna way es clean tissue does, and rziirt wiil assunie a temrierattirtæ that is often ritual-i ae the same es the underlyirrg tissiis. "ihsreiors, using such actditionai iiriegss irriproves the rslistvility of the originai, tnree-diinerisioiiei image. Eg., such a thermai image camera protiiioos a ihermal image of the region of interest Since en ucicior and the tests, but also most other body parts, are et inore then 30 “C (such as st shout 33-35 °C), which is ælntosi always much :none then einbieiit temperature, these structurss ars easily visible.

Also: since such a sensor rneasiires completely ciiifereiit, but reiovaiii parannoter, this additional image is also available for other purposes, such as hosith nioriitoriiig and general animal management. For example, it a test or iiodsr Quarter lies sn intianiinationï this inay show up in the thermographio irriage as si rise in ternpereture.

Actditionally or oternatively, the additional sensor oomprises a visual camera.

Sirniloriyg any peroeived rnatching (disyzoriiinuities in the visuei iamgs as compared with the original image may support the finding of an edge or other structure, while non~nietohing images support the abssnoe of such Structures Furthermore, there are very cheap, coinpsot, versatile and reliable visusi oameras avaiiabie. ln oarticuiar ernbedirnents, the control unit is arrongeizi to determine a movement for at least a part of said at least one additional image. Preisrably the cxt-ntrol unit is turthomiore to use said movement in cietscting the tooation of at least the tears with respect to the control nieans. 8peoificaily, the movement roiates to speed, direction of rnovemsnt or prefsrably both. Furthermore. the movement is, ivhensver possible, determine-ad for a structure already recognised in either the aciciitionai image or the (originei) image.

As rneniioneci above, anirrials are livs crsatures, that can move tinexpeotscily. More in particular, any movement of the rniiking animal as s whole will have a relatively large effect on the position of the teats. Thorefore, test iniaging is important in order to obtain an errangernent that can reliably connect tsat oups to tsats. But being abie to monitor and track such rnovenisnts in processing the image for detsoting the teets also helps in improving the rsiiabiiiiy of the milkirig arrangement. By using rnovornent 'iÜ 15 2D 30 WO 261 »â/íilálšål PCT/NL2013/050481 recognition for the edditionoi sensor, use man inte friade of ariy eveiietiie greater eeee in doirtg so then for' the image detection based on speokie patterns. in partioutar, the edditionai sensor coinprises a irieuai corner-a erreiiged to renaste-city obtain en additional irriage, wrierein the control unit coinprisss visuai image recognition software and is arranged to determine a rate ot' nioverhent for one or more struciuros as dotected in the actditionai image by the image recognition software. Stich niotioh detection is nirieh ntore eesiiy done with visuai teoriniciiies, erid its resuits con be used in corrscting any nreestirements and deterrninations for the origihai image and its subsequent processing into a threodimensionai image_ For example, when the direction ond rate of movement oi' a structure rscognissd as e test iip is deterrnined by rneeiis of the sdditionei visuei images, it becomes easisr to prediot where to find matohing parts of the speokie pattern in s suhssquent image in the crosecorroisting step. After att, ii' a movement is swirti the reiative ciispieoomerit of eg. a teat iip in the intogs-z can he such thai: the speckis pattern wiii be distorted with respect to the previous image to e rsiativeiy high degree. With khowiedge of the movement, that can be determined in psraiiei with the .ecquiring of the originai image, and oi' course irvith krrowiedge of the previousiy obtained three-dimensionei image, the :wow thros-dimensionai image and thus the speci-tie pattern to he expected can he predioted to a higher degree, so that the actuei determination of the new three» dimension-ai image can be performed quicker, The invention wiii now be described in more detail hy means of some iiondimiting einbodiiheiits and drawings, in which: - Figure i very diagrarrimaticaiiy shows a niiiitihg arrangernent 'i according to the inventiori, in a perspective side eievationai view; ~ Figure 2 very diegreinmeticoiiy shows a part of the milking orrangemont 1 in niore deteii; and ~ Figures 3A and 36 diagrarnmsticaiiy show a part of a reference image, and ofvan actuai image, respectiveiy.

Figure 1 very disgramrnaiticaiiy shows a mtiking arrangsment i according to the inventioh, in a. perspective side elsvationai view. 'líi 15 30 30 Wi) flifißílíilášál FCT/N L2U13/'05G4S1 The inilking arrangeineiit i cornprises a rnilking parlour 2, that is presentiy occupied hy a rniikirig ariiinal 3 having en iidder' 4 with teets 5. The arrangernerii further corrnorises e control unit 6 vrith a robot arm 'P2 here oerrying a teat cup 8. and with a camera Q having a field of view 'ill Herein, the centrera 9 is comprísed in the control nieans for controliing niovernent of the robot arm 7.

The rnilkirig parlour 2 may be a spatialiy fixed inilkiitg parlour, or may he a pannor on a roiery platform. The pannor may oompriee a single inilking box, or niay be a port or” a niulti~taarlour orrangernent. The robot arm 7 niey be o dedicated robot ann for iust a single rniiking periour or may he a diepiaoeable robot arm to opierate in a plurality of rniiking pariours 2, in particular in a herring bone setup or for e rotary piatforrn.

The control Linit 6 is arrariged to control ao. the milk-ing process, with settings for niilking, quality oontrol and so on, but is in particular aieo erranged to control operation of the robot arm 7 virith the lieip of information from the camera 9. Garnera 9 has a field of view 10 that is eirangeo' to he suitable to acquire a view of a relevant part of the milking anirrial 3 and/oi' the miiking parlour 2. ln particular, the rieid of view 'lO is arrenged to he ehie to comprise, when in use, a view of att least e part of the udder 4, teate 5 and at least one toai cup 8. The camera Q may be positionen on the robot arm T, on the control unit 6, directly connected to the iniiking parlour 2 or any other suitable poeitiori, as iong as in use a suitable field of view can be erronged. in each case, the threedirnensiorial image then provides coordinates in a respective coordinate frame, such as with respect to the robot arm, the control unit, the rnilkšng pariour, resoectively. in particular, positioning the carnera on the robot arm is very suitable for stationen; rniiking parlours. For iniiking errangernents with a roten; platform on which a plurality of milkiiwg parlours has been provided, it may be advonlageotis to provide the camera in a fixed position with respect to the ground.

Figure 2 very diegrarnmaticelly' shows a part of 'the milking arrangement 1 in more detail, in particular the camera 9 and the control unit ß.

Tine carriera Q cornprises an illuminatitzn unit 'ii and en imaging tinit 17. The illuminetion unit li cornprises o laser 12, eniitting a laser beam 13. A diriuser 14 and a ditiractive elenierwt 15 turn the beem 13 into en ernitted speckled bearn 16. 10 15 20 25 30 WU' 2014/014341 PCIVN 142013105948! "the inioging unit W, iievirwg tlne field of view 'l O ot the centern 9, oornprises irnegirig optios tät, that create en image of the tieio of iziew onto the sensor 19, that provides intaget: to the control unit o, that in turn oomprises en image processor 20 ond e. memory 21, An additional rgh camera has been indiceted hy numera! 22, anti hes o tield-oiflview 23, it is sxplioitly noted itere 'ritat the rgb camera 22 is not s pan of the Garnera 9 that is errangecl to ecquire images for gerierstirig; the throesciiritoitsional image. ln rise, the laser “iQ ernits ra laser beam 13 ot a tiseful wavelength, having a wevelengtli between 600 and 'lZOQ rim! preterohiy between 700 and 1090 nrn. NlR tree en sdvaritege ttiat ambient levels are relativeiy low and the sensitivity of rnost eyes is also low. Therefore, inconvenience for eg. cows ie relativeiy iow. The laser hsa-im then is sent through a oiffusor 14, such as e piece ot ground glass, that generator; a soeckie pattern in the boom, or s specltleo heem, hy interierenoe effects within the propegeted hearn, The rliftreotive element 15 itelps to control the brightness level in e direction transverse to the been: propogetiort direction. ii ie iiotecl that the position of the ditfraotive etentent 15 they otso he between loser 12 and ditfuser 14. The difiuser 14 :hey aiso he a different kind of specklo pattern generator, such ss a holographio plate, or a transoarency with en imprinteo pattern.

For more irrforniatioit regarding the oitiuser 14 and the ctiftrsctive element to, and regarding the technical background of this technique, reference is made to WO2OOW043038, incorporoteo hy reference, and in particular to page 5-8.

The sneoitlecl beam is emitted and iiits an object, in this case an Lidclor 4 vtfith teats S.

A part of the radiation is retlectect towards the imaging unit iT, in which the imeging optics “28 torrn an image of the retlected radiation onto the sensor tQ. the sensor 19 could be e occl sensor, a cmos sensor or the like. Advantogeously, the imeging unit coniprises e filter, trarismittirig substanttally only radiation with the wavelength of the laser source i2, in order to filter out as much ornoient light os possible. The image formed in sensor iQ is then sent to tive image processor 20, in which it is orooessed end ao compared to orte or more reference iniages stored in rnentory 21. "the ntemory 21 could also serve to store temoorarily or permanently the image from sensor 19, es well as any stihsequent image from saint sensor. lt is noteri that Figure 10 '35 20 25 3G WO 2014/91434! P(É'I'INI..ZU13IÜS(I4SI 2 is not in scale, ene thai the iiiuniinetion Linit *ii and the iniaging unit 17 are preferebiy positionen very eiose to eeeh rather. Furthermore, ii is not relevant wiiere, inet ie in »vhich pen oi the errengeriieni, the processing takes piece. Aiierrieiiveiy, the processing couici take piece within the imaging unii i? or in a device piiysiceiiy separate ironi the control Linit 6. Of boiirse, the coniroi unit 6 shouid be connected to ihe image processor 20 in such a way inet the reeuiis and iriiorniaiiioii of the letter azan be iieeci by the ioriner in the periorniing oi its coniroiiing tasks.

Vifiih reference numerei 22, en additional serisor in tiie form of a rgb Garnera has been inciibateci. Iis iieicfiof-viexr/ eriouici be riveriapçiirig with the iieirkoinziew “iO of the cemererimeging unit 17 es rnuch ae poseibie. The rgb cernere 22 een/es to provide a visoai image for eupporiing the iormeiiivn of the 'iiiree»dirnerieir.>riai image and the iniege enci object recogniiiori in said ihree-ciirrierisioiwai image: Thereto, the rgb camera is epereiiveiy connected to the image processor 20. The letter can cornpere en image from the rgb Garnera 22 to the aciuei image from the imeging unit 1? and or io iis sirbsequeni ihree-dirnerieionai iniege. ii a structure or, edge or object is apparently deiecied in the (aciuei or) threedirnensionei image bot eonneihirig is deiermineci to be wrong, such es a wrorg number ef :ieiecteci ieeis, then the rgb image niey be taken into account. For exampie, assume five ieais iiave been deterrnined in the threeoimensionei image, but the rgb image shows e continuous coiour' and/or iiiteneity on the position (ie. epetiei engie) of one of ine tears and its imrnedieie surroundings, then ii is safe to conciude thai thai particular position does ÛÛÉ Cfifiíêïifl <9 'iiêåå in a simiiai' fashion, ii is possible to use the rgb camera 22 es a means to determine movement of objects in the image. ii ie reiaitiveiy easy to deierrniiwe movement by means of en optioei (rgb) ceniere and image. "Fherr if a structure in the ihree~ dimensioner! iniage has been coupied (crosecorreieied) io the rgb image, in other words its posiiien and distance are known, e ciiepiecemeni in tiie rgb irriage can be coupied to e dispiaoenient in the three-dimensionen imagei Then, the new and dieiorted speokie pattern can be predicied to some degree. This inekee the cross» oorreieting of the riew erieckie raaitiern in the eubseqiient image from imaging unit 17 eesier.

(Il 10 15 20 130 WO Iêíliâ/'Ol-llfiål PCT/NL20l3/05Û-»ll8l Figure 3A diegramntaticaiiy shows e part of e reiereme image, and Figure SB ciiegreinniaticeily shows e part of en actual image taken by the inieging unit 17. “liite reference irriage 3A is en image of tiie erieckied beani, taken at a lrnown oistarttze. “the image show/e the pattern of the epecltlee as present in space et eeid clietence. .lust for convenience, the pattern is shown as ccrnpletelyi regular. This greatiy einipïifies the following discussion. Hcvrever, it is to be noticed that a random, iicnerepetitive pattern is rnuch rriore convenient in practice. ae this allows to identify a part of the actual iniege much eesier ertcl with much more certairity. Furthermore, elthriiigli dois tweve been inclirzeted, this does not niean thai there ere only bright spets while all the rest ie riark. Rather, the cicts indicate brighter parts in the image, while the parts around and inbetweeii the dets ie derker, but not necessariiy completely dark, even without a view to arribient light.

The actual image 323, highly ioealiseci in this case, shows how the errtitted speckled beein 16 would be imaged when illumineting a part of a miiking animal 3. One can see a pattern ct the speclrles. Some parts are lecking dcte, ohviotisly the parts where no reilective object is present. Furthermore, some parts :to show a pattern, that, however, has been cletornted with respect to the original. 'the deformation of the pattern, and in peirticular the distance bettveen neighboiiring speciiles, and also the (average) size of the epectries is an indicetion ot the orientation and the distance with respect to the camera (or imaging unit) of the sits-face retiecting the speckle pattern, hut can also else he compared with the rlistence et wiiicli the reference image 3A was taken. For exampte, e part pattern sligiilly above the centre ot Figure 38 shot-vs speckles at about the same distance es in Figure 3A, and also in about e square pattern. This inciicates that the reflectlng etirtace is Oriented substentielly trensversely with respect to the camera and at about the same distance es for image 3A. To the left and right thereof, the speckles are rnore and inore closer together, end run et? to the top of the page. This inslicates that the surface hencls further away, ie. bencis to the hack, ario ftirtherrriore ie slightly inolinect such as to face the ground. in all, the central part of the iniage seems to resembie roughly a sembcircie, better: e half» Sphere. Looking :nere closely, four Structures can be found having a more or less cyiindrical shape with a rounded rip. These ere obviously the teats. To the extreme left end right edges of the Figure BB, similar cylinorical Structures can be seen, which i!! iQ i5 2G WO ZÛN/'GHSÅI FCT/N L2013/0å043l Ii can bra rænogriised as the iegs, wniiet the iarga strustura ai tns top of ttie Figure vviii be the: betty. Nnta that in this case tha image anaiysis is a kinci of two--step analysis.

First: a: 'tnrea--diniensinnai image is cræateci by ciætermining, for as niany points or speckies as inossibie, the spatiai coorciinaies tnæreot. Then, the tnrewáintæiisionai intagit is turtnsr analysed in order to sxtract stirfaces and snapes tnerefrain, by mreans of intaget and shape racogriitirin techniques. "these are per se deerned known to the: skiiiect petrson. it wiii be ciear tittat in the above Figure 38, the picture, is much ciearer than wiii be the case in isractice, Fer exampiie. there is no dirt, nciise or background signal present, the Structures (tags, ticiciær, teats) are aii separated and easiiy recognisabie. On the miner nandr it is nioræ cšitfictiit to actuaiiy positicin the strtictures in space (te, deterininæ the right orientatioiw and distance) with a cornpisteiy reguiai' pattern, as it is ritat possible to ciistinguisn parts in a repetitivez pattern. 'i'nereto, an irregular' pattern is used, for exam pie raridorn or reguiar thøugit nnn~repetitive patterns. With strcti patterns, it is easier to crossæorræiate parts of the coliæoted image and sirniiar parts of the reference intag-e, as no so-caiied wrappirig probiern occursr Reference is again friade tø WO2007/O43Ci36.

The atnove embociiinæiwts arici drawings ara not intenciæci to iimit the invænticiii, the: scene of wiiich is determined by tita- appended ciaiins.

Claims (8)

'IG 15 20 25 30 Wi) 2014/01 4341 PCTIN LZIiitš/Oätišâí

1. 2. CLAiit/iâ i. Miiking arrarrgairtartt (i) oornprisirtg: - a niiiking pariour (2) with test Cops (8), - a robot arm (7) for connocting tha taat cuos to tha iaats (5) of a miiking animai (3) - a controi ftir-sans (6, 9; ti, 'iïi for controiiirig the robot arm, wnarsiiw said control maana coniptíso: « a conaraiii tight sourca (12) arrangaci to eniit a cotiarent tuaain (33) of optical radiation, - a spackia tuattarn generator ('14) arrangad to irnpart a spackia pattern to said baam, inaraby torrning a soackiad boom ('26), ~ a carttara (9) ior rapaatadiyf obtainirig an intogs of a raiiactad part of said ioearn, and - a oontroi tinit (6) arrangoci to term a thraa-dinionsionai image frorn said image by contparing said imaga wittt at iaast one reference raiiactioii image of said baam and taken witn said camara, and otatisticaiiy cxoss-corraiatirtg said aoaoitia pattern in said imaga with said spackia pattarri in said at toast ons raiaranca ratiatztion image, wiiarain the control unit is further arrangad to identity said iaats and to Gatact the iocation ttisreof »vith raaoact to tiva carnara, on the basis of said tiiraa-ziirtiansionai image,

2. iviiilting arrangamant according to oiaim i, wharain the controi unit is 'further arrangad to datact at iaast one of said taat supa and tha position tharadi with respect to tha camera, on the basis of said threa--dimansioiwai image.

3. iiiiiiking arrangsment according to any pracading ciaim, wherein the controi nteans has a singis cainara that is arrangad to rapaatediy obtain an image of a reiiactad part of said beam from which image the controi unit ionris a threa- dimarisionai image.

4. Miiking arrangamani according to any praceciing cziaim, wharain tha spackiæ pattern generator is arrangao to ganarata a constant and random speckied pattern,

5. Miiking arrangamant according to any prscading ciaim, further comprisiiwg an additionai sensor ciiifarant ironi said camera, said sensor being arranged to obtain at 10 WG 201-4/ÜIä3-làï }?(I'l{“/'NL2013/050481 13 laws: :ma addlïlmal image of a ræflecïed part m' said bsanfz in a way that dlffærs 'frorn the way said carnæfa abïains said lznage, and wherem the control :mit is arranged to use said aclrlillnnal šrmage än iderzflfylrwg at least said tsats.

6. lvlllklng arrangemerli accclrcillwg to clalm 5, wherelrl the addltlønal sensor cornpršses a thermal image carnera.

7. _ Nlllklrxg arfangsrnent according to olalm 5 or 6. whæræln the additional sensor oomprlses a visual camera.

8. Mllklng arrangement according to any of clalms 53, wherem the cønlrol unit is arrangecí in deïefmíne a fnavemenl for al least a pan of said at least ones addlllønal image, and preferabšy to Llse said movement in dstælttlng tlne lncaïiøn clf at least the tests wltll respect to tha control rneans.