This article was downloaded by: [North Dakota State University]On: 16 November 2014, At: 13:27Publisher: Taylor & FrancisInforma Ltd Registered in England and Wales Registered Number: 1072954 Registered office: Mortimer House,37-41 Mortimer Street, London W1T 3JH, UK

International Journal of Computer IntegratedManufacturingPublication details, including instructions for authors and subscription information:http://www.tandfonline.com/loi/tcim20

Assessment of laser-based reverse engineering systemsfor tangible cultural heritage conservationTiziana Segreto a , Alessandra Caggiano a & Doriana M. D'Addona aa Fraunhofer Joint Laboratory of Excellence on Advanced Production Technology,Department of Chemical, Materials & Production Engineering , University of Naples FedericoII , P.le Tecchio 80, 80125 , Naples , ItalyPublished online: 14 Jun 2013.

To cite this article: Tiziana Segreto , Alessandra Caggiano & Doriana M. D'Addona (2013) Assessment of laser-based reverseengineering systems for tangible cultural heritage conservation, International Journal of Computer Integrated Manufacturing,26:9, 857-865, DOI: 10.1080/0951192X.2013.799781

To link to this article: http://dx.doi.org/10.1080/0951192X.2013.799781

PLEASE SCROLL DOWN FOR ARTICLE

Taylor & Francis makes every effort to ensure the accuracy of all the information (the “Content”) containedin the publications on our platform. However, Taylor & Francis, our agents, and our licensors make norepresentations or warranties whatsoever as to the accuracy, completeness, or suitability for any purpose of theContent. Any opinions and views expressed in this publication are the opinions and views of the authors, andare not the views of or endorsed by Taylor & Francis. The accuracy of the Content should not be relied upon andshould be independently verified with primary sources of information. Taylor and Francis shall not be liable forany losses, actions, claims, proceedings, demands, costs, expenses, damages, and other liabilities whatsoeveror howsoever caused arising directly or indirectly in connection with, in relation to or arising out of the use ofthe Content.

This article may be used for research, teaching, and private study purposes. Any substantial or systematicreproduction, redistribution, reselling, loan, sub-licensing, systematic supply, or distribution in anyform to anyone is expressly forbidden. Terms & Conditions of access and use can be found at http://www.tandfonline.com/page/terms-and-conditions

Assessment of laser-based reverse engineering systems for tangible culturalheritage conservation

Tiziana Segreto, Alessandra Caggiano* and Doriana M. D’Addona

Fraunhofer Joint Laboratory of Excellence on Advanced Production Technology, Department of Chemical, Materials & ProductionEngineering, University of Naples Federico II, P.le Tecchio 80, 80125, Naples, Italy

(Received 20 June 2012; final version received 14 April 2013)

The process of acquiring the geometry and shape of a part and reconstructing its digital model is known as reverseengineering (RE). This approach is usefully employed in fields as diverse as product design, design modification,geometrical inspection, worn or damaged parts repair or remanufacturing, when physical object drawings, documentationor computer models are not available. The recent scientific and technical developments of RE methods and tools havebroadened the possibilities of applications in the field of cultural heritage conservation ranging from reproduction (e.g. viarapid prototyping), maintenance (e.g. computer-aided repair), multimedia tools for education and dissemination (e.g. virtualmuseums), to artefact condition monitoring (e.g. computer-aided inspection) and many more. The first stage of the REprocedure is digital data acquisition that can be carried out by means of several different tools. The selection of the 3Ddigitising system is crucial as it directly affects the process time and the quality of the point cloud, which determines thefinal digital model. In this research work, following the EC FP7 open topic on ‘Equipment assessment for laser basedapplications’ compiled in Horizon 2020, two non-contact laser-based RE systems, respectively, based on a coordinatemeasuring machine and a portable 3D scanning equipment, are utilised for the digitisation and reconstruction of a free-formtangible cultural heritage artefact to comparatively assess the RE system’s performance in terms of process time, accuracyand ease of use.

Keywords: reverse engineering; laser scanning; cultural heritage; coordinate measuring machine; portable scanning system

1. Introduction

The traditional manufacturing sequence starts with thedesigner’s idea and conception of functional constraints,performance specifications, etc., goes through the con-struction of a computer aided design (CAD) model andends with the fabrication of the physical part.Contrarywise, the reverse engineering (RE) process startswith an existing physical object, provides for the acquisi-tion of the object’s geometry and shape and realises thereconstruction of the object’s digital model: it is alsoreferred to as ‘physical-to-digital’ process (Bidanda,Motavalli, and Harding 1991; Segreto, Caggiano, andTeti 2010).

Nowadays, RE is widely used in numerous applica-tions, such as manufacturing (from the analysis of thecompetitor’s products to quality control of industrialparts) (Yao 2005), industrial design (models creation forvirtual reality environments) (Fischer and Park 1998;ElMaraghy and Rolls 2001), and technical, industrial andcultural heritage conservation, renovation, maintenanceand repair (Bernard et al. 2007; Raja and Fernandes 2008).

The development of RE methods has allowedfor interesting applications for the conservation of tangiblecultural heritage artefacts that are of crucial importance tothe study of human history as they provide a concrete

source of information and an essential contribution to thevalidation of theories. The recognition of the relevance ofthe past and of the things that tell its technical, industrialand artistic story is the reason of all the efforts spent in theprotection of objects from earlier times, i.e. the preserva-tion of tangible cultural heritage artefacts (Levoy et al.2000). As a matter of fact, the accessibility of an actualhistorical object, rather than a reproduction, is a uniqueopportunity to touch the past, but several risks are relatedto that. As an example, such objects can be damaged bythe hands of visitors, by the light required to display them,or by other risks related to making an object known andavailable (Levy and Dawson 2006).

Modern advances in technology have offered newsolutions to broaden the visibility of cultural heritageartefacts while preventing such damages. As an example,RE methods provide a valuable technological solutionable to acquire the shape and the appearance of artefactswith extraordinary precision (Varady, Martin, and Cox1997; Berndt and Carlos 2000; Rho et al. 2002). Theemployment of RE methods for cultural heritage artefactpreservation can be developed for several purposes suchas reproduction (faithful copies can be easily and quicklyobtained from 3D models through machining processes orrapid prototyping), computer-aided repair (appropriate

*Corresponding author. Email: alessandra.caggiano@unina.it

International Journal of Computer Integrated Manufacturing, 2013Vol. 26, No. 9, 857–865, http://dx.doi.org/10.1080/0951192X.2013.799781

© 2013 Taylor & Francis

Dow

nloa

ded

by [

Nor

th D

akot

a St

ate

Uni

vers

ity]

at 1

3:27

16

Nov

embe

r 20

14

software tools allow the virtual assembly of objects forartefact reconstruction without actual physical interven-tion), virtual museum realisation (location of the 3Dobjects in their original environment through the creationof suitable scenarios), inspection and monitoring (detec-tion of artefact modifications over time) (Papaioannou,Karabassi, and Theoharis 2001; Pieraccini, Guidi, andAtzeni 2001; Buzzichelli et al. 2003; Bernard 2005;Segreto, Caggiano, and Teti 2010, 2011).

For all these categories of applications, a large numberof systems based on different approaches and mechanismshave been developed and utilised. The first step of the REprocedure is digital data acquisition. This is a critical stageof the RE procedure; as a matter of fact, the choice of theRE data acquisition method affects the quality of theacquired point cloud and, consequently, the resultingreconstructed surface or CAD model (Chivate andJablokow 1993).

There are many different methods for acquiring shapedata, which use diverse mechanisms or phenomena to inter-act with the surface or volume of the object of interest(Bernard 1999). The main distinction is between contactmethods, that make use of devices such as mechanicaltouch probes, and non-contact methods, commonly basedon light, sound or magnetic fields. Probably, the broadest andmost popular methods for geometrical data acquisition arethe optical-based ones that offer reasonably fast acquisitionrates. With regards to the expanding field of optical sensor-based devices, the EC FP7 open topic on ‘Equipment assess-ment for sensor and laser-based applications’, compiled inHorizon 2020 (www.2020-horizon.com), emphasises theimportance of activities aimed at the assessment of laser-based equipment for manufacturing applications, includinglaser-based RE systems (cordis.europa.eu/fp7).

In this framework, the present research work aims atcomparatively assessing two different non-contact REscanning equipments based on laser sources in terms oftheir performance in 3D data acquisition and digital recon-struction of a cultural heritage artefact consisting of anantique porcelain sculpture of complex geometry, repre-senting the bust of a child. The acquisition procedure andthe following digital processing of the acquired free-formgeometry are illustrated and compared in order to evaluatethe performance of both systems in terms of ease of use,required processing time and final model quality.

2. Case study

The cultural heritage artefact under study is an earlytwentieth century bisque porcelain sculpture manufacturedin Limoges, reproducing one of the two original terracottabusts which depict the children of Alexandre-ThéodoreBrongniart (Louise and Alexandre), made in 1777 byJean-Antoine Houdon, a distinguished NeoclassicalFrench architect (1741–1828) (www.louvre.fr).

The sculpture, made of porcelain on a blue base withgilt rings, reproduces the head, shoulders and upper chestof the young Alexandre (Figure 1) and has the followingfeatures:

● Overall dimensions: 190 mm × 130 mm × 80 mm(height × width × depth)

● Weight: 0.5 kg● Origin: Limoges, France● Dating: 1923● Preservation state: very good conditions, without

chips, cracks or repairs.

3. Data acquisition through diverse 3D laser scanningsystems

3D digital geometry acquisition of the described porcelainsculpture was carried out by means of two diverse opticalRE systems using scanning lasers. The two systems arerespectively based on a coordinate measuring machine(CMM) and a portable scanning system (PSS).

Figure 1. Early twentieth century porcelain sculpture depictingthe bust of the young Alexandre Brongniart.

858 T. Segreto et al.

Dow

nloa

ded

by [

Nor

th D

akot

a St

ate

Uni

vers

ity]

at 1

3:27

16

Nov

embe

r 20

14

Both RE systems work on the basis of triangulationmethods, using the position and angle between a lightsource and a photo-sensing device to calculate the pointcoordinates. A laser beam is focused and projected at aspecified angle on the artefact surface, while a photosen-sitive device (video camera) senses the reflection of thesurface. Thus, by using geometric triangulation, from theknown angles and distances, the position of a surface pointrelative to a reference plane can be calculated. The REscans carried out in this way are relative measurements ofthe surface of interest and the triangulation method allowsfor data acquisition at very fast rates. The triangulationaccuracy is determined by the resolution of the photosen-sitive device and the distance between the artefact surfaceand the scanner.

3.1. Coordinate measuring machine

A CMM is a high-precision measuring device consistingof four main components: the machine, the measuringprobe, the control or computing system and the measuringsoftware. Its three axes form the machine’s coordinatesystem. The CMM utilised for this research work(Dea Global Image, Hexagon Metrology, Grugliasco,Turin, Italy) is characterised by a precision error, E,equal to 4.9 µm for point-to-point measurement, a repeat-ability of 1.7 µm and a resolution of 0.1 µm. The non-contact probing system mounted on the central carriage ofthe CMM is composed of a probe head and the actualprobe, Metris LC 15. The latter is an optical laser devicewith a high resolution, an accuracy of 8 μm and a laserstripe scanner (scan speed: 19200 pps) working on thebasis of the triangulation principle.

As the physical constraints of this system only allowto acquire the geometrical data from a limited region of anobject’s surface, multiple scans must be taken to comple-tely reverse engineer an artefact. Hence, the 3D digitaldata acquisition of the porcelain bust was carried outthrough several subsequent scans characterised by thefollowing parameters: point distance = 0.15 mm, stripedistance = 0.15 mm, overlap = 0.2 mm. Each scan isexecuted with a specific probe head orientation, controlledby the combination of two angles, A and B (Figure 2).

Figure 2. Probe head structure with two rotation axes (A-Bangles).

Figure 3. (a–b) Two different positions of the bust for CMM laser scanning.

International Journal of Computer Integrated Manufacturing 859

Dow

nloa

ded

by [

Nor

th D

akot

a St

ate

Uni

vers

ity]

at 1

3:27

16

Nov

embe

r 20

14

In order to digitally acquire the full sculpture shape, 35diverse A-B angles combinations were employed. Moreover,two different positions of the bust (Figure 3) were required toget the entire sculpture geometry because of the constraintsrelated to the maximum range value of the A angle (equal to97.5°). As a result of the selected scan parameters, the largenumber of the two-angle combinations and the two differentpositions required for the complex sculpture geometry, dataacquisition took a rather long time of about 7 working days.The first position of the sculpture on the CMM allowed toacquire the major part of the geometry (Figure 4a) andrequired the longest time. As the A angle constraints didnot allow to reach the area comprised between the chin andthe neck (Figure 4b), a second positionwas employed to scanthis specific area (Figure 4c).

When two distinct point clouds have to be merged, thedecision to be taken is whether to merge the data at thepoint cloud level, before further processing, or to processeach view to produce a corresponding partial geometricmodel, and then to merge the latter.

In this case, the first option was selected as a singlepoint cloud leads to a larger but more consistent datastructure. Thus, the two separate point clouds were alignedand merged in order to obtain a single comprehensivepoint cloud of the sculpture geometry (Figure 4d).

3.2. Portable scanning system

The 3D PSS consists of a high-precision CIMCORE(Hexagon Metrology) Infinite II SC anthropomorphic armwith seven rotational axes, provided with an optical lasersystem. The arm has an ergonomic pistol grip to enable themanual measurement of 3D points at any orientation withinthe arm’s spherical reach (2.8 m), with a precision of±0.040 mm and a repeatability of ±0.028 mm. ThePerceptron Scanworks v4 optical laser system mounted on

the arm allows to collect up to 23.000 points per second witha precision of 0.024 mm.

The 3D digital data acquisition of the porcelain bustwas carried out through subsequent line scans charac-terised by the following parameters: profile = mat white(referring to the object surface colour), scan rate = 30 Hz(maximum available value).

Each scan was executed by manually following thesurface profile without restriction to a specific angle orien-tation; in this way, data acquisition was extremely fast(1 hour).

Only one sculpture position was sufficient to acquirethe entire sculpture geometry as the arm could be rotatedwith a large freedom of movement (Figure 5). As shownin Figure 6, the various scans are highlighted by differentcolours and need further processing in order to reducescan overlapping.

In Table 1, the details of data acquisition and digitalmodel reconstruction for the two laser-based scanningsystems are summarised.

4. Reverse engineering digital models reconstruction

The digital model reconstruction of the two acquired pointclouds obtained through the two diverse RE systems wasperformed using the same 3D metrology software plat-form: Polyworks V11 by Innovmetric (InnovMetricSoftware Inc., Quebec, Canada) (Reference Manual 2011).

This software consists of several modules, each dedi-cated to a specific phase of the RE procedure. TheIMAlign module allows to scan the objects and align theresulting datasets. The IMEdit module covers severalessential steps for polygonal models editing, generationof curves, non-uniform rational basis spline (NURBS)patches and models that can be exported as CAD filesreadable by other software tools. The IMInspect module

Figure 4. (a–d) Point clouds acquired through the CMM laser scanner.

860 T. Segreto et al.

Dow

nloa

ded

by [

Nor

th D

akot

a St

ate

Uni

vers

ity]

at 1

3:27

16

Nov

embe

r 20

14

allows to compare the acquired data (e.g. point cloud) witha reference (e.g. CAD model), measure the dimensions ofspecific features and generate comparison and verificationreports.

For CAD file reconstruction and data comparison,several steps were required:

● Point cloud processing – different operations wereperformed to improve the two point clouds: noiseand overlap reduction, redundant points deletion.The resulting clouds were then wrapped to draw atriangular surface connecting every three datapoints, thus obtaining the so-called ‘polygon mesh’.

● Polygon Model editing – the geometries based ontriangles (polygon mesh) were enhanced throughseveral actions (e.g. fill holes, reconstruct mesh,optimise mesh, etc.). In Figure 7, the polygonmeshes obtained from (a) the CMM and (b) thePSS acquired point clouds are shown.

● Curves and patches generation – curves werecreated on the polygonal model to obtain closedsets for NURBS patch construction. Because thesculpture was free-form geometry, automaticcurve generation was rather difficult. Hence, thecurves automatically generated by the softwareneeded further manual improvement to achievethe four-sided boundaries required for patch gen-eration. Figure 8 shows the curves and patchesgenerated by the software for (a) the CMM and(b) the PSS polygonal models, indicating in violetthe patches to be modified and in yellow thepatches surrounded by closed sets of four magne-tised curves. As it can be noticed, many errorsoccurred and a large number of curve editingoperations such as edges and corners reconstruc-tion, boundaries creation and fitting were requiredto improve curves and patches. The final result isshown in Figure 9 for (a) the CMM and (b) thePSS curves. The final NURBS patches were thenemployed to create the NURBS models over thetwo polygonal models.

Figure 6. Portable scanning system: acquired point cloud.

Table 1. Data acquisition and digital model reconstruction details.

Data acquisition system CMM Portable scanning system

Line scans 253 51Number of points 1.251.149 104.529Number of triangles 2.501.750 207.650Number of curves 4967 2232Angles 35 diverse A-B angles combinations were

employedEach scan was executed by manually following thesurface profile without restriction to a specific angleorientation

Position of the sculpture 2 1Duration of data acquisition About 7 working days Data acquisition was extremely fast (1 hour)Duration of digital model

reconstructionAbout 7 working days About 5 working days

Figure 5. Portable scanning system: acquisition of the bust.

International Journal of Computer Integrated Manufacturing 861

Dow

nloa

ded

by [

Nor

th D

akot

a St

ate

Uni

vers

ity]

at 1

3:27

16

Nov

embe

r 20

14

● CAD phase – the NURBS models were finallyexported as IGES files, as shown in Figure 10 for(a) the CMM and (b) the PSS models.

All the described steps for the digital reconstruction of thesculpture model starting from the two acquired pointclouds required about 5 working days for the PSS pointcloud and about 7 working days for the CMM point cloud.

5. Reverse-engineered digital models comparison

A comparison between the results obtained with the twodiverse laser scanning RE systems, CMM and PSS, wascarried out on the polygonal models generated from the

acquired point clouds. The selected 3D deviation parameterwas the shortest distance between the two polygonal meshesof Figure 7 and is reported as a coloured map in Figure 11.The chosen maximum distance is ranged between ±0.5 mm,where the red colour represents the +0.5 mm distance and theviolet colour the −0.5 mm distance. The areas in red and bluecorrespond to the highest deviations between the CMM andthe PSS models, verified for the smallest and most complexfeatures of the sculpture such as the eyes, the mouth and thecurls. These high deviations correspond to a perceivablequality difference between the two models that can be easilyverified by visual examination of the two final CAD modelsshown in Figure 12.

Undoubtedly, the CMM CAD model is the most accu-rate and truthful of the two reverse-engineered digital

Figure 7. (a–b) Polygonal models obtained from (a) the CMM and (b) the PSS point cloud.

Figure 8. (a–d) Curves and patches generated by the software for (a, c) the CMM (b, d) the PSS polygonal model.

862 T. Segreto et al.

Dow

nloa

ded

by [

Nor

th D

akot

a St

ate

Uni

vers

ity]

at 1

3:27

16

Nov

embe

r 20

14

reconstructions of the sculpture, although the processingtime for the CMM procedure was much longer than thatfor the PSS procedure, particularly as regards the pointcloud acquisition (over 50 hours versus 1 hour). At anyrate, it may be worth noting that the investment cost forthe CMM-based scanning system is about 3 times higherthan for the PSS.

6. Conclusion

In this research work, a case study of laser-based REprocedure applied to a tangible cultural heritage artefacthas been illustrated by examining all the steps required toconvert the complex free-form geometry of an antiqueporcelain sculpture into its 3D digital representation.

The availability of a 3D digital model could offerseveral opportunities within the cultural heritage as well

as the manufacturing fields: as an example, the manufac-turing of scaled reproductions of tangible cultural heritageartefacts via rapid prototyping method based on RE digitalmodels represents a fast developing business sector foradditive manufacturing companies.

In the framework of the EC FP7 open topic on‘Equipment assessment for laser based applications’ com-piled in Horizon 2020, a comparative assessment of twodiverse laser scanning RE systems were employed toacquire the geometry of the free-form artefact, the firstmounted on a CMM and the second on a PSS.

The point clouds collected with the two RE systemswere then processed by applying the same 3D digitalmodel reconstruction procedure and tools. The referenceparameters selected for the assessment and comparison of

Figure 9. (a–b) Improvement of curves/patches for (a) the CMM and (b) the PSS models.

Figure 10. (a–b) NURBS models obtained from (a) the CMM (b)the PSS.

Figure 11. Comparison between the CMM and PSS polygonalmodels; the two models are superimposed in the same figure.

International Journal of Computer Integrated Manufacturing 863

Dow

nloa

ded

by [

Nor

th D

akot

a St

ate

Uni

vers

ity]

at 1

3:27

16

Nov

embe

r 20

14

the RE systems performance are related to the ease of use,the required scanning and processing time as well as thequality of the obtained 3D digital models of the artefact.

As expected on the basis of hardware features consid-erations, the CMM-based RE procedure proved to be themost accurate and truthful. However, the point cloudacquisition time was more than one order of magnitudelonger than that for the PSS-based RE procedure and theinvestment cost for the CMM-based system is about threetimes higher than that for the PSS-based system.

The analysis of the obtained results takes into considera-tion not only the accuracy of the final 3D model of the free-form object, but also the required time for final modelachievement and the investment relevance for systempurchase.

In view of future developments, the results obtained inthis research work will be employed to identify and carryout effective selection procedures for the most appropriateRE system in the different applications within the manu-facturing as well as the cultural heritage fields, such asproduct design, re-design and repair and/or cultural heri-tage reproduction, maintenance and monitoring. Particularattention will be given to the issues of RE system selectionfor scaled reproduction via additive manufacturing.

AcknowledgementsThis research work was carried out within the framework of theExecutive Program of Scientific and Technological Co-operationbetween Italy and China, Ministry of Foreign Affairs, under theSignificant Bi-Lateral Project on: Reverse Engineering Methodsfor 3D Digital Reconstruction, in collaboration with the TienjinUniversity, Tienjin, China (duration: 2010-2013). TheFraunhofer Joint Laboratory of Excellence for AdvancedProduction Technology (Fh - J_LEAPT) at the Department ofMaterials and Production Engineering, University of Naples

Federico II, is gratefully acknowledged for its support to thisresearch activity.

ReferencesBernard, A. 1999. “A Review of State-of-the-Art Reverse

Engineering.” In Proceedings of the TCT Conference,177–188. Nottingham, October.

Bernard, A. 2005. “Virtual Engineering: Methods and Tools.”Journal of Engineering Manufacture 219 (B5): 413–422.

Bernard, A., F. Laroche, S. Ammar-Khodja, and N. Perry.2007. “Impact of New 3D Numerical Devices andEnvironments on Redesign and Valorisation ofMechanical Systems.” CIRP Annals – ManufacturingTechnology 56 (1): 143–148.

Bidanda, B., S. Motavalli, and K. Harding. 1991. “ReverseEngineering: An Evaluation of Prospective Non-ContactTechnologies and Applications in Manufacturing Systems.”International Journal of Computer IntegratedManufacturing 4 (3): 145–156.

Berndt, E., and J. Carlos. 2000. “Cultural Heritage in the MatureEra of Computer Graphics.” IEEE Computer Graphics andApplications 20 (1): 36–37.

Buzzichelli, G., L. Iuliano, D. Pocci, and E. Vezzetti. 2003.“Reverse Engineering: Applicazioneal Aecupero diBassorilievi.” Progetto Restauro 25: 3–7.

Chivate, P. N., and A. G. Jablokow. 1993. “Solid-ModelGeneration from Measured Point Data.” Computer-AidedDesign 25 (9): 587–599.

ElMaraghy, W., and C. Rolls. 2001. “Design by Quality ProductDigitization.” CIRP Annals 50 (1): 93.

Fischer, A., and S. Park. 1998. “3D Scanning and Level of DetailModelling for Design and Manufacturing.” CIRP Annals 47(1): 91.

Levoy, M., K. Pulli, B. Curless, S. Rusinkiewicz, D. Koller,L. Pereira, and M. Ginzton, S. Anderson, J. Davis, J.Ginsberg, J. Shade, and D. Fulk. 2000. “The DigitalMichelangelo Project: 3D Scanning of Large Statues.” InACM SIGGRAPH 2000, Computer Graphics Proceedings,131–144, New Orleans, LA, July.

Figure 12. (a–b) NURBS models obtained from (a) the CMM (b) the PSS.

864 T. Segreto et al.

Dow

nloa

ded

by [

Nor

th D

akot

a St

ate

Uni

vers

ity]

at 1

3:27

16

Nov

embe

r 20

14

Levy, R., and P. Dawson. 2006. “Reconstructing a Thule WhaleboneHouse Using 3D Imaging.” IEEE MultiMedia 13 (2): 78–83.

Papaioannou, G., E. A. Karabassi, and T. Theoharis. 2001.“Virtual Archaeologist: Assembling the Past.” IEEEComputer Graphics and Applications 21 (2): 53–59.

Pieraccini, M., G. Guidi, and C. Atzeni. 2001. “3D Digitizing ofCultural Heritage.” Journal of Cultural Heritage 2 (1): 63–70.

Polyworks V11, Reference Manual, 2011, Innovmetric.Raja, V., and K. J. Fernandes, eds. 2008. Reverse Engineering:

An Industrial Perspective. 242 p. London: Springer-Verlag.Rho, H.-M., Y. Jun, S. Park, and H.-R. Choi. 2002. “A Rapid

Reverse Engineering System for Reproducing 3D HumanBusts.” CIRP Annals 51 (1): 139–143.

Segreto, T., A. Caggiano, andR. Teti. 2010. “3DDigital Reconstructionof a Cultural Heritage Marble Sculpture.” In 7th CIRP Interna-tional Conference on Intelligent Computation in Manufacturing

Engineering – CIRP ICME ’10, 116–119, Capri, June 23–25,University of Naples.

Segreto, T., A. Caggiano, and R. Teti. 2011. “Diverse NonContact Reverse Engineering Systems for Cultural HeritagePreservation.” In 7th International Conference on DigitalEnterprise Technology – DET 2011, 486–493, Athens,September 28–30, University of Patras, ISBN 978-960-88104-2-6.

Varady, T., R. R. Martin, and J. Cox. 1997. “Reverse Engineeringof Geometric Models – An Introduction.” Computer-AidedDesign 29 (4): 255–226.

Yao, A. W. L. 2005. “Applications of 3D Scanning and ReverseEngineering Techniques for Quality Control of QuickResponse Products.” The International Journal of AdvancedManufacturing Technology 26 (11–12): 1284–1288. AccessedApril 2013. http://www.2020-horizon.com/

International Journal of Computer Integrated Manufacturing 865

Dow

nloa

ded

by [

Nor

th D

akot

a St

ate

Uni

vers

ity]

at 1

3:27

16

Nov

embe

r 20

14