753

A Web-enabled Configuration System for Interior Design

Maura Mengoni1, Damiano Raponi1 and Roberto Raffaeli2

1Università Politecnica delle Marche, m.mengoni@univpm.it, d.raponi@univpm.it2Università degli Studi eCampus, roberto.raffaeli@uniecampus.it

ABSTRACT

Web-enabling technologies represent the next generation of design environments to design and man-ufacture complex systems, such as them characterizing contract furniture. In the context of webapplications to facilitate and support teamwork in collaborative product development, the paperpresents a CAD-based infrastructure for the 3D visualization of co-designed solutions, the on-linecustomization of furniture items and the creation of a shared relational database of products, architec-tural scenes and knowledge-based rules guiding configuration. A double-level geometry is presentedto manage 3D web representation and product structure. A use case is adopted to show main platformfunctionalities and possible advantages for the extensible contract furniture cluster.

Keywords: web-enabling technologies, collaborative product development, CAD, WebGL

1. INTRODUCTION

Nowadays, contract furniture (CF) represents apromising opportunity for SMEs to be competitivein the worldwide market. Contract furniture is atransversal business which aims to provide finishedcommodities for hospitality, retailing, as well as forstores, offices and restaurants.

The process of CF design requires the involve-ment of different actors (product designer, architects,supplier, etc.) that are often distributed worldwideand work on the same project to achieve a sharedgoal. An high level of collaboration and synchro-nization is required, from the integration of single“pieces of work” which are individually developed(i.e. tasks, decisions) to the combination of differ-ent working actions due to the actors’ working way(i.e. work at computers, talk to other designers orspecialist, solve problems by acting on the prod-uct models) [4]. The different social background,knowledge and skills of the involved stakeholderstrigger research toward the creation of adequatesupporting tools for proper data visualization andmanagement.

A previous research work [13] has outlined themain characteristics of contract furniture design andthe main problems to manage such extensible andtemporary cluster of involved companies, differentin size, adopted information technologies, developed

products, project goals, skill, etc. Two main openissues has emerged:

• no Computer Supported Cooperative Work sys-tem is dedicated to this complex applicationarea, whose needs regard the simultaneous sup-port of information exchange along the fur-niture life cycle, the management of multipleand conflicting design constraints and processrequirements and finally the creation and shar-ing of the whole furnishing Bill of Materials[7,8];

• the management of an high level of furnish-ing customization is complex as personalizationdepends on numerous requirements: from theneeds of the target market, the standards ofthe country, the customer profiles, the contracttypology, the design style, the target cost to theexpected performance, etc. It is much more thana simple variation of the item dimension as itis extended to finishing, functions, aesthetics,etc. In addition it does not regard the singlefurniture item, but the whole space. As a con-sequence a CAD-based solution must manageconfiguration at different levels of abstraction.A browser-based tool could enable users to visu-alize and interact with complex 3D configura-tion [14].

Computer-Aided Design & Applications, 12(6), 2015, 753–764, http://dx.doi.org/10.1080/16864360.2015.1033341© 2015 CAD Solutions, LLC, http://www.cadanda.com

754

Contract furniture design lacks of integrated, flex-ible and cost-effective supporting solutions. The Webis surely the most powerful tool to provide a light-weight and an operation system-independent plat-form for users to search, browse, retrieve, shareand manipulate information in the context of the CFdesign. Most research works propose a CollaborativeProduct Data Model (CPDM) and a constraint-basedCollaborative Design Process Model (CDPM) to facili-tate the management and coordination of the collab-orative design process as well as design knowledgemanagement [20]. In other works [5–21] the Internetis leveraged to build an environment that connectsdistributed CAD software clients to a centralizedproduct data server for collaborative design. Sometechnological difficulties emerge and require to beovercome. Firstly, large CAD files require an unbear-able down-loading time over the Internet. Besides,parts are usually modeled with different software sys-tems or even with different versions. The visualizationof the CAD model would not be possible if therewere no general standards for 3D graphical represen-tation and effective transmission strategies over thenetworks.

In conclusion, no solution offers an integratedenvironment for collaborative data management,product modeling and customization, review anddecision-making [13]. In this context the presentresearch work proposes a platform which consists offour main user interfaces: one dedicated to the onlineproduct configuration and 3D visualization of the cus-tom solution, one to the selection of the personalizeditems and their integration into a 3D architecturalspace, one to manufacturing companies to definemodels and design contractions and one to supportthe co-design of integral solutions.

The paper mainly focuses on the description of theweb-enabled geometry representation and configura-tion system that allows 3D CAD models of architec-tural spaces and furniture items to be customized andshared by designers and manufacturers within thenetwork of companies. Configuration is based on a setof knowledge-based rules that guarantee the coher-ence of the designed solutions against manufacturingand installation constraints.

Therefore, the main contributions are: the devel-oped 3D-web based visualization of integral solu-tions and single items; the adopted infrastructure toexchange and synchronize data among the differentdesktop and internet based applications; the struc-ture of the virtual prototype as a compendium ofboth geometric, functional, technological features forenabling companies to contribute with their specificknowledge; the developed graphic rendering algo-rithms which are homogenous for web and CAD-based tools; and, finally, the modality to guarantee thecoherence of information flowing across the systemmodules by sharing models and data structures.

After the description of the architecture ofthe developed configuration system, a test case is

implemented to demonstrate the advantages for thefinal users. In fact, several stakeholders are involved,from the architect which combines design productsto achieve environments with higher aesthetic value,to the company which can promote a better contex-tualization of the own products. Finally, the end useris advantaged by knowing about new “Made in Italy”products and modern living environments.

2. BACKGROUND

2.1. 3D Model Sharing on the Web

In order to cope with the requirements of collab-orative systems on webs with limited bandwidthcapability, the research community has initially inves-tigated in innovative light-weight 3D standards and3D streaming communications [7]. As a result somededicated formats, such as VRML, X3D (eXtensible3D), W3D (Web 3D) and MPEG-4 were launched.

The VRML files describe the 3D scene in termsof geometric objects, triangular meshes, operationsand properties of the scene. It has the advantage ofbeing written in text format. The major disadvantageof VRML is the dimension of the files since no com-pression has been built in. The download and displayspeeds are not satisfied.

X3D is a major upgrade from VRML aiming to morelight-weight representation. It is being developedunder the Web3D Consortium’s (www.web3d.org)standardization process. Nodes in X3D are repre-sented in XML tags so as to take full advantagesand potentials of XML on the Internet. MoreoverX3D incorporates numerous 3D techniques includingadvanced rendering and multi-texturing, NURBS sur-faces and IEEE Distributed Interactive Simulation (DIS)networking.

MPEG-4 has been proposed to define a binary com-pression format to encode VRML in binary represen-tation. As the major objective of adopting MPEG-4 isfor multi-media applications, MPEG-4 supports mediamixing and audio composition, and it can easily mixwith rich forms of media, video and audio for multi-media collaborations in a Web-enabled environment.

Behr et al. [4] provided an overview of the avail-able 3D web technologies with a division in plug-in,i.e. Java3D, O3D, and plug-in-less solutions, i.e. Can-vas3D or other solutions that use 2D browser toolsto simulate a 3D pipeline. VRML and X3D languagesare actually developed to describe 3D scenes in termsof geometry, material and illumination, while theirrendering inside a web browser requires the instal-lation of specific plug-ins or applets. Examples arethe Active X technology which operates on Microsoft’sweb browser and operating system, or other compo-nents, such as a Java Applets which run on differentplatforms [11].

Experiences of architectures to share 3D contentsvia web browser can be found in Visintini et al. [18]and in OSG4Web [3, 15]. The first consists in a browser

Computer-Aided Design & Applications, 12(6), 2015, 753–764, http://dx.doi.org/10.1080/16864360.2015.1033341© 2015 CAD Solutions, LLC, http://www.cadanda.com

755

plug-in that uses an OpenSceneGraph library thatsupport Level-of-Detail (LOD) objects and can load dif-ferent 3D model formats. Among them, Java3D is awell-known high-level programming API for visualiz-ing and manipulating 3D models. Java3D has rich setof 2D and 3D objects and behaviors and it encom-passes 3D geometry compression and LOD. A binarygeometry compression format is utilized both as arun-time in-memory format, as well as a storageand network format. Finally Java3D supports a widevariety of file formats to accommodate many vendor-specific CAD formats, interchange formats and VRML.

These latter peculiarities are particularly useful forlarge scale visualizations. The drawback of these pur-pose developed technologies is the need to installexternal components necessary for its functionality.To solve this issue, the WebGL approach was devel-oped and it is expected to grow considerably inthe future [6, 10]. WebGL is an API developed toextend the capability of JavaScript language in orderto control the graphic card from the most widespreadbrowsers (Firefox, Chrome, Safari). It is based on theOpenGL ES 2.0 standard to be supported also byembedded and portable devices.

Actually many graphics libraries rely on WebGL.For instance, Google O3D is a graphic API expresslydesigned to create interactive 3D application withina browser [12]. It was conceived as a browser plug-in, but one year later it was turned into a JavaScriptlibrary based on WebGL.

2.2. Configuration Systems in the FurnitureDesign

Generally speaking, given a set of components withcertain properties and ports connecting them, con-figuration can be defined as the activity of findinga solution in combining such components while ful-filling a set of constraints [9, 17]. The set of con-straints that restricts product variants is related totechnical limitations, economic factors and produc-tion processes [16]. Narrowing the scope to the CFdesign, configuration systems are intended as propri-etary or open-source platforms, which allow 2D and3D environments to be created and furniture itemspositioned and rendered. They need to be easy-to-use,intuitive and low cost.

Web-enabled configuration systems allow datato be easily shared through the web. The userimports 3D model from some shared libraries.Some examples of existing systems are Sweethome3D (http://www.sweethome3d.com/) and DomusPlan-ner (http://www.domusplanner.com/). However, suchsystems poorly support the technical configuration ofthe products, its structure, rules and constraints, sothat they are suitable for the final customer but notexpert users such as architects or manufactures.

Other CAD-based configuration systems includededicated commercial configuration systems or

open-source platforms. They implement function-alities to handle CAD models, configure themin a certain environment and to generate com-plete BOM. They adopt a single company perspec-tive, so they cannot support collaboration and co-design within an extended network. Some exam-ples are Metron (http://tesysoftware.net/), 3CADevolution (http://www.3cadevolution.it) and Mobilia(http://mobiliasoft.com/).

An comprehensive analysis of the configura-tion systems lead to include the BIM (BuildingInformation Modeling) technology, which includecommon commercial systems such as ArchiCAD(http://www.graphisoft.com/archicad/), Revit (http://www.autodesk.com) and Allplan (http://www.nemetschek-allplan.eu) [1]. They implement functionsto generate a CAD model of an architectural buildingcharacterized by its geometry, spatial relationships,information about materials and building elements,costs and project schedule [2]. They support the inte-rior design but cannot support the extensive collabo-ration among several companies and stakeholders.

In conclusion, the analysis of the availabletechnologies has highlighted the lack of solutionsdedicated to the contract furniture. In particular,web-enabled configuration platforms are desirableto manage technical features, product variants, thewhole environment configuration, rules, real-time col-laboration and high-quality rendering. A knowledgeapproach leverages the development of productswhich can be configured in several variants. Built-in rules allow the designer to create configurationswhich respect the user needs, permit multiple alter-natives to be quickly tested, and avoid design errorscaused by the lack of technical knowledge.

3. APPROACH AND PLATFORM DESCRIPTION

This section presents a CAD-Based infrastructureto support the 3D visualization and configurationof furniture items, the creation of a shared rela-tional database of products and integral solutions,the definition of design rules and, finally, the config-uration of the whole architectural spaces by selectingand positioning furniture items according to the pre-defined rules. Before detailing the proposed systemarchitecture, the adopted product structure and thegeometrical representations necessary to meet the CFrequirements are described.

3.1. Product Structure and GeometryRepresentation

An original representation is introduced to managethe geometry, the appearance and the configurationrules of the products. Fig. 1 depicts the main elementsof the representation.

Product is here intended in a broad and transversesense, including an entire environment, a group of

Computer-Aided Design & Applications, 12(6), 2015, 753–764, http://dx.doi.org/10.1080/16864360.2015.1033341© 2015 CAD Solutions, LLC, http://www.cadanda.com

756

Fig. 1: Representation of the product: structure, variants, graphics, rules.

products (e.g. kitchen), single product instances (e.g.dishwasher) and product inner structures (e.g. draw-ers of a cabinet). The product is captured by the con-cept of occurrence. An occurrence defines the relativeorientations of its child occurrences. The whole ambi-ent is therefore a hierarchic structure constituted bya tree of occurrences. Such hierarchy allows pieces ofconfiguration to be realized separately, combined andreused.

Each occurrence contains the definition of a prod-uct through a list of codes. A code is an instance of aphysical product as it appears in the company repos-itories (e.g. Enterprise Resource Planning or Prod-uct Lifecycle Management systems). It includes theitem geometrical representation, its non-geometricattributes and embedded light definitions. The differ-ent codes act as variants of the occurrence. Only onecode is active at a time.

The geometry of a code is defined on two levels.The first one is a render mesh whose vertices include

texture mapping coordinates. The second one is ahidden simplified B-Rep analytic representation to beused as the basis for geometric functionalities such asmating, part measuring and positioning. Fig. 2 showsthe two representations in case of a bathroom sink.A mesh capturing the details of the bowl and theaesthetic features provides the render geometry. Asimplified geometry consists of boxes correspondingto the sink overall dimensions and a hole as a ref-erence for the tap. The advantage of such duality isto have the possibility to implement low-cost func-tionalities for precise part positioning, mating andmeasuring of the distances.

The memory request due to the use of a sim-plified geometry in addition to the rendering modelis negligible. In fact, the bounding box or similarelementary shapes are suitable for the majority of thecases to provide sufficient geometric elements, suchas faces, edges and vertices, to mate and measure thedeveloped composition. The B-Rep representation of

Fig. 2: Example of geometric representation of a bathroom sink.

Computer-Aided Design & Applications, 12(6), 2015, 753–764, http://dx.doi.org/10.1080/16864360.2015.1033341© 2015 CAD Solutions, LLC, http://www.cadanda.com

757

such simple shapes is very light and does not wasteresources of the computer, realizing an acceptablecompromise.

The geometry is input through Step files for theB-Rep geometry and Vrml files for the render mesh.The two formats have been chosen for being diffusedand flexible. In fact, step files contain the definition ofsolid geometry in terms of geometric and topologicaldata. They can be created with the majority of com-mercial CAD systems. On the other hand, the render-ing model requires meshes, texture mapping, materialand lights definition. Vrml files include such datawhich can be in such a way transferred from othersoftware system. However, the proposed productdefinition includes more extended characterizationof the rendering properties, such as custom lights,bump mapping, shadows, etc . . . . Such attributes aredefined by the developed user interfaces and saved ina proprietary format.

As defining a new product, three cases are distin-guished:

• Vrml + Step files: The Vrml contains the meshdefinition, texture mapping, material attributesand the textures images. The Step provides forthe simplified geometry. The bounding boxes ofthe two representations are checked to be coher-ent each other. The Vrml is created by a systemwhich has functionalities for advanced mate-rial definition and texture mapping, for instance3DS Max by Autodesk.

• Only Vrml file: in this case the simplified B-Repis computed from the bounding box of themesh.

• Only Step file: in this case it is assumed thatthe geometry is detailed, for instance it comesfrom a CAD model of the design department.Functionalities are provided to compute themesh and the texture mapping from the B-Rep.The B-Rep is then substituted by its boundingbox.

3.2. Configuration Rules

The product exhibits several degrees of configuration.The first one is given by the codes which basically rep-resent different geometric solutions. Secondly, eachproduct variant may then have in turn several graphicvariants, e.g. different materials combinations to beapplied on the same geometry. The set of mesheswhich are used to render the object is split in groups,i.e. portions of the geometry with the same materialdefinition. A graphic variant maps material defini-tions to each mesh group. Finally, the geometry canbe modified by anisotropic scaling.

A set of parameters is introduced to control thestatus of the occurrence, such as the current code, thestatus of the geometry and the appearance. A param-eter is a variable which can assume numeric or textual

values in a certain domain. Rules operate on theseparameters to implement configuration logics. Param-eters can be freely defined by the user. Some of themare reserved and created by the system, such as:

• Variant: an integer controlling the active codeindex;

• GraphicVariant: an integer controlling the activegraphic variant index;

• Index: an incremental read-only index to distin-guish repetitions of the same code in the wholeconfiguration;

• Quantity: an integer value causing copies of theoccurrence to appear in the configuration. If thevalue is zero the occurrence is eliminated fromthe configuration;

• DeltaX, DeltaY, DeltaZ, RotX, RotY, RotZ:numeric values to transform the occurrence bya parametric roto-translation;

• ScaleX, ScaleY, ScaleZ: parameters controllingthe anisotropic scaling of the occurrence;

• Width, Depth, Height: Dimensions of the bound-ing box of the code geometry. Such values areread-only.

Rules are defined as expressions in the followingform:

Pi = f (P0, P1, . . . , Pj , . . . , PN ) where j �= i (3.1)

Every parameter is computed as function of theothers as in equation 3.1. The adopted syntax isstandard and recalls MS Excel formulas (examples inequation 3.2). An exclamation mark is used to sepa-rate an occurrence name from the parameter name.The inference engine is able to detect parametersdependencies and rearranges the order of the rulesto solve them.

Handle!Quantity = SELECT (Cabinet!Variant; 2;3;4;1;0)

Handle!Spacing = SELECT (Cabinet!Variant;360;180;180;0)

Handle!DeltaZ = −Handle!Spacing ∗ Handle!Index (3.2)

Each parameter can be exposed thanks to a spe-cific flag. If exposed, a parameter becomes usable asconfiguration input option. The user can change thevalue to obtain different product definition thanks therecalculation of the rules and consequent updating ofthe other parameters.

Finally, rendering materials and lights are definedwith a good level of complexity. The material includesstandard parameters such as diffuse color, specu-lar color, transparency, etc . . . , and maps for dif-fuseness, transparency, reflectiveness and bumping.Light description comprises ambient, directional, spotlights options but also custom illumination diagramsfrom ELUMDAT files (*.ltd) [19]. Lights can be definedin the environment or be geometrically associated toproducts such as lamps.

Computer-Aided Design & Applications, 12(6), 2015, 753–764, http://dx.doi.org/10.1080/16864360.2015.1033341© 2015 CAD Solutions, LLC, http://www.cadanda.com

758

3.3. Real Time Rendering

The scene rendering relies on the parallel comput-ing capabilities of the PC graphic cards (GPU). Therequirements for high quality rendering, such as per-pixel shade computation, shadows projection, bumpmapping, custom lights definition, is achieved thanksto the programming capabilities of the GPU.

The rendering behavior of a graphic card is con-trollable through the Shading Languages, which allowdevelopers to customize the fixed rendering pipelinethanks to some shading algorithms, i.e. Vertex Shaderand Fragment Shader. In the present work, theOpenGL Shading Language (GLSL) [10] is exploited toreach the desired high quality rendering effects onboth desktop applications and web pages.

A Vertex Shader is a piece of code which runs forevery vertex given to the GPU. The purpose is to trans-form each vertex’s 3D position in virtual space to the2D coordinate at which it appears on the screen alsocomputing the depth value for the Z-buffer. Fig. 3

reports an example of GLSL code for a Vertex Shader.On the contrary, the Fragment Shaders runs for everypixel on the screen and basically compute color andother attributes.

The adopted GLSL code can be used on both desk-top and web applications. In fact, the OpenGL APIsallows activating interactions between the CPU, wheregeometric data are managed, and the GPU. On a webpage, the advent of the WebGL and HTML5 technolo-gies has given the possibility of controlling the GPUthrough the JavaScript [14].

3.4. System Architecture

A major contribution in the field of the furniture con-figuration is given by the proposed architecture forthe distributed model sharing (Fig. 4). The productsare stored on a remote repository in a server on thecloud. Information retrieved in the system databaseflows across four different platform modules mostly

Fig. 3: Example of GLSL code from a Vertex Shader.

Fig. 4: System architecture, user roles and types of exchanged data.

Computer-Aided Design & Applications, 12(6), 2015, 753–764, http://dx.doi.org/10.1080/16864360.2015.1033341© 2015 CAD Solutions, LLC, http://www.cadanda.com

759

through a proprietary file format (*.dn) which embedthe described representation scheme.

Data sharing modalities, i.e. type of informationand access, are subjected to the specific user role asfollows:

• Administrator: it has full access to the systemand the responsibility of the managements ofthe shared data. Such role is in charge of thecluster leader company;

• Company: it loads its own products to theserver by the Definer module. It has also read-only access to other company products and itcan use them for sample compositions. A localreplica of the DB is provided to allow off-lineoperability. Synchronization is allowed once theuser connects to the Internet and logs with itsspecific role;

• Designer: it refers to architects and other spe-cialists which use the platform (Web Cata-log, Configurator and Co-Designer modules) todesign contract environments. The designer roleallows products to be downloaded to a local DBand the configured solutions to be updated andshared;

• End user: a generic user which browse the Inter-net by the Web Catalog module searching forfurniture solutions.

More specifically the features of the system imple-mentation and the user interfaces of the softwaremodules are here described:

• Web Catalog: a web-based virtual marketplacepromoting in an appealing way the productsoffered by different manufacturers. The soft-ware allows user identification, authenticationand tracking to achieve a complete profile. Oncelogged, the user can view a rich catalog of prod-ucts and assess all predefined variants by ahigh quality rendering. The catalog is written inASP.NET code to produce dynamic Web pages,applications and services and adopts WebGL forrendering interactive 2D and 3D graphics ofproduct models, scene and solutions within anycompatible web browser;

• Configurator: a configuration tool able to sup-port the 3D configuration of both productsand architectural space according to a set ofknowledge-based rules and best practices. Itemsare positioned in the environment from the Vir-tual Catalog by following manufacturing guide-lines, technical constraints and geometrical rela-tionships among objects in space. The systemis interfaced and synchronized with the VirtualCatalog to keep the selected products and solu-tions ever updated. The Configurator is imple-mented on the .NET Framework adopting object-oriented computer languages and exploits the

programming capabilities of the graphic cardthrough the shading language to realize 2D and3D photorealistic rendering.

• Definer: a management tool to enable com-panies uploading products and solutions intothe catalog, preset the product variants (e.g.colors, finishing, functions, features) and addtechnical documentation suited for the differentfurniture stakeholders (e.g. contractors, design-ers, architects and end-users). For each itemthe company provides the 3D model, indicateexisting or customizable characteristics, spec-ify possible accessories or auxiliary functions,define customizable features and allowed rangeof modification, add installation and configu-ration constraints and finally attach technicalinformation such as manuals and data sheets.The module is developed by the same imple-menting technology of the configuration systemand is synchronized with the platform-shareddatabase.

• Co-Designer: a collaborative design tool to allowdesigners to interact with company techniciansin case some special product requirements areneeded.

From a technical point of view, the synchroniza-tion among the server, the definer and the config-urator systems is allowed by remote connection todatabase through the OLE DB standard while files aretransferred through the FTP protocol. The commu-nication between the server and the Web Catalog isbased on the standard HTTP protocol. The geomet-ric data are transmitted from the server to the clientside in XML format, parsed by JavaScript code andtemporary stored by the web page DOM.

4. AN APPLICATION TEST CASE: THE SERVICEDAPARTMENT

The described platform is completely developed andtested thanks to the DesigNET initiative, an Ital-ian project promoting innovation and Made in Italylifestyle in the context of companies operating in theCF sector.

The application of the proposed platform to adeveloped test case is described in this section. Itconcerns an application in a typical example of CF,i.e. a serviced apartment. It is a type of furnishedapartment available for short-term or long-term stays,which provides amenities for daily use.

Ten SMEs were involved in the project which wasled by a designer who developed the concept andcoordinated the work of the companies. The apart-ment is composed of four main areas: the kitchen,the living room, the bedroom and the bathroom asshown in Fig. 5. In these areas companies have workedtogether to integrate their products considering func-tional, aesthetic and dimensional constraints.

Computer-Aided Design & Applications, 12(6), 2015, 753–764, http://dx.doi.org/10.1080/16864360.2015.1033341© 2015 CAD Solutions, LLC, http://www.cadanda.com

760

Fig. 5: Geometric model of the studied serviced apartment.

4.1. Products Definition through the DefinerSoftware

As a first step, companies uploaded some items intothe platform thanks to the Definer tool. The softwarewas installed as a desktop application in each com-pany that used it to define the products and populatea local DB.

A new product can be created with or withoutgeometry providing a unique name and identifier.The choice of creating a product without geometryis to group more articles under a wider definition.The geometry is loaded from CAD models in STEPand/or in VRML formats as described above. Productis then populated with attributes, variants, differentdimensions, components and colors.

For example, a cabinet has two or more draw-ers with different handle options and is equippedwith oven, hob, and combine various finishes. Prod-uct attributes are given by: name, space type, com-pany name, category, line, code, description, notes,attached technical documents, preview, market tar-get, contract type, pricing, product type and thevisibility (Fig. 6). The visibility attribute set the avail-ability of the product across the platform, i.e. the WebCatalog, the Configurator, both or none. Also sometags are added to classify the product on the basisof specific design features such as eco-sustainability,hygiene, multi-sensoriality and safety.

The product instance is enriched with new codes,i.e. variants, or with occurrences, i.e. child parts. Vari-ants and child occurrences are defined from scratchor are reused from other products. Graphic variantsare then associated to codes.

For instance, five codes and five occurrences aredefined for the cabinet. Codes activation and occur-rences visibility, as well as dimensions and orien-tation in the space, are controlled by the parame-ters and rules which determine valid combinations.

Fig. 6: Non geometrical attributes of a productdefinition in the Definer software.

Additional parameters are added to fulfill specialneed of customization. Some parameters are thenchosen to be exposed to the user of the Web Catalogand/or the Configurator.

In particular, for the cabinet test case four customparameters are added in the parent occurrence: onefor the type of handle, one for the wood color, onefor the finishing of the work plane and one for thetype of the hob. Another parameter is added to thehandle child occurrence to set the spacing betweenthe handles.

At the end, eighteen color combinations, eighttypes of handle, ten finishes of the work plane andtwo types of hob are defined (Fig. 7). Nine rules are

Computer-Aided Design & Applications, 12(6), 2015, 753–764, http://dx.doi.org/10.1080/16864360.2015.1033341© 2015 CAD Solutions, LLC, http://www.cadanda.com

761

Fig. 7: Variants of the cabinet (left) and tree of configurations from the Definer software (right).

input to manage the quantity and the spacing amonghandles, the code of the active handle, the graphicvariant of the base, the graphic variants of the workplane, the presence and the variant of the hob.

The product definition is then completed with theinstallation constraints. They relate to the maximumdistance to the power socket and the request forcontact to the wall.

Once ended the product definitions, the companycan log it into the server and update the server DB toshare the documents across all applications.

4.2. Product Sharing through the Web Catalog

As new products are uploaded on the server, theyare accessible from the Web Catalog website. Prod-ucts are classified according to categories, i.e. kitchen,bath, living, wellness. The catalog has free access toallow products to be publicized. The private user canbrowse the pages, view the 3D rendering, change theconfigurations, download documentation and contactthe producer by email. A search function is also pro-vided on the basis of criteria such as company name,contract type, pricing.

The members of the DesigNET network, i.e. com-panies and architects, have a special login to theWeb Catalog. They can open a workspace where per-sonal data are organized in two main containers:“my projects” and “my collaborative sessions”. Thefirst one contains the developed solutions uploadedto the server, while the second one traces the co-design sessions held with the company technicians

to solve specific design problems. Collaborative ses-sions can be triggered on a specific product searchedin the catalog or from the items used for a developedsolution.

4.3. Products Usage in the Configurator Software

The Configurator is used by an architect or a designerto create a configuration with a wizard composed byfive main steps. The Configurator makes use of theproducts downloaded from the server after synchro-nization with the local DB. The configurator providesread-only access to products so they can be used andmodified in the limits fixed by the companies in theprevious definition phase.

The tool is here described taking the ServicedApartment as example. A new configuration startswith the definition of some project attributes such as:the name of the project, the type of the environment(i.e. hotel apartment, commercial space, etc . . . ), thetarget market, the location, the pricing, the dimen-sions of the environment, the number of the rooms.The geometry of the environment is loaded from aSTEP file.

In the second step the designer details the modelof the Serviced-Apartment adding some tags to detectthe rooms. He also input key-points for indicatingthe position of windows, doors, electrical socket anddrainages. In the third step the designer places itemsin the environment. Drag and drop functionality areprovided to easy the task of choosing an item from

Computer-Aided Design & Applications, 12(6), 2015, 753–764, http://dx.doi.org/10.1080/16864360.2015.1033341© 2015 CAD Solutions, LLC, http://www.cadanda.com

762

the available product tree and put it in the graphi-cal area. The item can then be configured by choosingsuitable values from the exposed parameters: variant,dimension, color and other options.

The system allows the products to be exactly posi-tioned in several ways, such as snapping, mating andalignment of faces and edges, or by imputing precisetranslation and rotations. Measurement and alterna-tive rendering options are available to easy the posi-tioning task. Items are positioned in the environment

by following manufacturing guidelines, technical con-straints and geometrical relationships among objectsin space. Referring to the cabinet case, the designerselects the variant, i.e. with two drawers or with ovenand hob, the color of the wooden doors, the typeof the handles, the finishing of the work plane andthe type of the hob. When selecting the variant withoven and hob, the system alerts the user with thedesign guideline of positioning the product close toan electrical socket.

Fig. 8: The test case, from the product definition to the configuration of a Serviced-Apartment.

Computer-Aided Design & Applications, 12(6), 2015, 753–764, http://dx.doi.org/10.1080/16864360.2015.1033341© 2015 CAD Solutions, LLC, http://www.cadanda.com

763

The fourth step takes care of saving the worklocally and in the remote server. If saved in the cloud,the configuration is available in the workspace intothe Web Catalog for sharing and/or launching webcollaborative sessions.

The fifth and last step provides tools to exportconfiguration data. Six options are available:

• export the 3D configured environment to aVRML file

• export the plant of the environment to a 2D DXFfile

• generate a BOM of the products in the environ-ment

• generate a printable report with the data ofthe project, the data of the products and theinstallation guidelines

• export the data sheet and the other attachmentsof the products

• saving the 3D model of the products in STEP orVRML format

The exported data is useful to share the configura-tion among the stakeholders and to provide technicalinformation to trigger the procurement or productionof the selected products. Fig. 8

4.4. Results

System experimentation is still at a preliminary leveldue to the large amount of work to be done to pop-ulate DB and formalize the implicit knowledge of allinvolved stakeholders in implemented rules.

The project of a Serviced-Apartment was reallyuseful to identify the main system potentialities andthe drawbacks to be overcome. Users’ feedback ispromising. All actors, from manufacturers to design-ers recognized the importance of the platform toshare project evolution and items customization fromthe preliminary concept development. The integra-tion with company ERP and the interoperability withmost of the adopted CAD increase system accept-ability and easiness-to-upload items, define possiblevariants, create custom solutions and integrate prod-ucts from different manufactures with a set of sharedtechnical and geometrical constraints, The graphicrendering of the virtual Catalog allows companies topresent their offers in an amazing and attracting wayand final users to intuitively assess their choices.

The adoption of two levels for geometry repre-sentation, in the Definer and in the Configurator,results to be useful to switch between a render meshto view the products in a realistic image and a B-Rep representation necessary to position parts andother geometrical functionalities. Data exchange andsynchronization latency and hence system efficiencyappear to be proper enough for the applicationsidentified in contract furniture. The configuration

rules of the products are a key aspect to guaran-tee the technical validity of the developed solutionsand make possible to integrate items from differentmanufactures without design errors.

5. CONCLUSIONS

A CAD-based configuration system exploiting web-enabling capabilities is presented. Implementationresults are described in detail focusing on how thesystem is able to share and synchronize informa-tion among different platform modules and how datacoming from different sources is keep updated.

The case study for experimentation is the designof a Serviced-Apartment. It has demonstrated thesystem functionalities and the flow of work acrossthe stakeholders. The preliminary results outline theusability of the system and the achieved effectivenessin terms of tool flexibility, time to market reduc-tion and capability to manage design conflicts. Allthese parameters need to be objectively measured bycollecting more use cases.

REFERENCES

[1] Arayici, Y.; Coates, P.; Koskela, L.; Kagioglou,M.; Usher, C.; O’Reilly, K.: Technology adoptionin the BIM implementation for lean architec-ture practice, Automation in Construction, 20,2011, 189–195. http://dx.doi.org/10.1016/j.autcon.2010.09.016

[2] Azhar, L.; Hein, M.; Sketo, B.: BuildingInformation Modeling (BIM): Benefits, Risksand Challenges, Leadership and Manage-ment in Engineering, 11(3), 2011, 241–252.http://dx.doi.org/10.1061/(ASCE)LM.1943-5630.0000127

[3] Baldissini, S.; Manferdini, A. M.; Masci, A.: Aninformation system for the integration, man-agement and visualization of 3D reality basedarcheological model from different operators,Proceedings of the 3rd ISPRS InternationalWorkshop 3D-ARCH 2009, 2009, Trento, Italy.

[4] Behr, J.; Eschler, Y.: X3DOM – A DOM-based HTML/X3D Integration Model, Proceed-ings of the 14th International Conference on3D Web Technology, 2009, 127–135. http://dx.doi.org/10.1145/1836049.1836076

[5] Cheng, J.; Han, C.; Law, Y.; Zhang, Y.; Kumar,B.: Web-enabled model-based CAD for design,Proceedings of the International Conference onComputing in Civil and Building Engineering,2010.

[6] Di Benedetto, M.; Ponchio, F.; Ganovelli, F.;Scopigno, R.: SpiderGL: A JavaScript 3D Graph-ics Library for Next-Generation WWW, Pro-ceedings of the 15th International Confer-ence on Web 3D Technology, 2010, 165–174.http://dx.doi.org/10.1145/1836049.1836075

Computer-Aided Design & Applications, 12(6), 2015, 753–764, http://dx.doi.org/10.1080/16864360.2015.1033341© 2015 CAD Solutions, LLC, http://www.cadanda.com

764

[7] Fuh, I.; Li, W.: Advances in collaborative CAD:the state of art, Computer Aided Design, 37(5)2005, 571–581. http://dx.doi.org/10.1016/j.cad.2004.08.005

[8] He, F.; Han, S.: A method and tool for human-human interaction and instant collaboration inCSCW-based CAD, Computer in Industry, 57(8–9), 2006, 740–751. http://dx.doi.org/10.1016/j.compind.2006.04.019

[9] Hulubei, T.; Freuder, E.; Wallace, R.: TheGoldilocks problem, AI EDAM 2003, 17(1),2003, 3–11. http://dx.doi.org/10.1017/S0890060403171028

[10] Khronos Group, Open standards for mediaauthoring and acceleration, http://www.khronos.org, 2009.

[11] Manferdini, A. M.; Remondino, F.: A Review ofReality-Based 3D Model Generation, Segmen-tation and Web-Based Visualization Methods,International Journal of Heritage in the DigitalEra, 1(1), 2012, 103–121. http://dx.doi.org/10.1260/2047-4970.1.1.103

[12] Manferdini, A. M.; Remondino, F.: Reality-based3D modeling, segmentation and web-basedvisualization, Digital Heritage, 6436, 2010,110–124. http://dx.doi.org/10.1007/978-3-642-16873-4_9

[13] Mengoni, M.; Peruzzini, M.; Raffaeli, R.; Raponi,D.: A web-based platform to support contractfurniture design, Computer Aided Design &Applications, 11(5), 2014, 533–543. http://dx.doi.org/10.1080/16864360.2014.902684

[14] Moncur, R.; Jensen, C.; Teng, C.; Red, E.: Dataconsistency and conflict avoidance in a multi-user CAx environment, Computer Aided Design& Application, 10(5), 2006, 727–744. http://dx.doi.org/10.3722/cadaps.2013.727-744

[15] Pescarin, S.; Calori, L.; Camporesi, C..; Ioio, M.D.; Forte, M.; Galeazzi, F.; Imboden S.; Moro, A.;

Palombini, A.; Vassallo, V.; Vico, L.: Back to 2ndAD A VR on-line experience with Virtual RomeProject, VAST’08 Proceedings of 9th Intenra-tional Symposium on Virtual Reality, Arche-ology and Cultural Heritage, 2008, 109–116.http://dx.doi.org/10.2312/VAST/VAST08/109-116

[16] Raffaeli, R.; Mengoni, M.; Germani, M.: Improv-ing the link between computer-assisted designand configuration tools for the design ofmechanical products, Artificial Intelligence forEngineering Design, Analysis and Manufac-turing, 27(1), 2013, 51–64. http://dx.doi.org/10.1017/S0890060412000388

[17] Sabin, D.; Weigel, R.: Product configurationframeworks – a survey, IEEE Intelligent Sys-tems, 13(4), 1998, 42–49. http://dx.doi.org/10.1109/5254.708432

[18] Visintini, D.; Siotto, E.; Menean, E.: 3D mod-eling of the St. Anthony Abbot Church in S.Daniele del Fiuli (I): From laser scanning andphotogrammetry to Vrml/X3D model, Proceed-ings of the 3rd ISPRS International Workshop,2009.

[19] Wallner, G.: Geometry of arbitrary light distri-butions, Proceedings of the 3th InternationalConference on geometry and graphics, 2008,Dresden, Germany.

[20] Wang, J.; Tang, M.; Song, L.; Jiang, S.:Design and implementation of an agent-based collaborative product design system,Computer in Industry, 60(7), 2009, 520–535.http://dx.doi.org/10.1016/j.compind.2009.03.001

[21] Zeng, J.; Chen, W.; Ding, Q.: A Web-basedCAD system, Journal of Materials Process-ing Technology, 139(1–3), 2003, 229–232.http://dx.doi.org/10.1016/S0924-0136(03)00225-5

Computer-Aided Design & Applications, 12(6), 2015, 753–764, http://dx.doi.org/10.1080/16864360.2015.1033341© 2015 CAD Solutions, LLC, http://www.cadanda.com