Digital Models – Associative Geometry: Architecture

Digital Models – Associative Geometry: musealization peculiarity of monuments in extension Águas Livres Aqueduct as a case study

Ana Cristina Chalaça Gil

Extended abstract of the thesis to obtain the Master degree in

Architecture Juri President: Professora Doutora Teresa Frederica Tojal de Valsassina Heitor Supervisor: Professora Doutora Maria Helena Neves Pereira Ramalho Rua Juri: Professora Doutora Ana Paula Filipe Tomé

November 2011

Digital Models – Associative Geometry: the peculiarity of monuments in extension Águas Livres Aqueduct as a case study

Ana Cristina Chalaça Gil Under supervision of Maria Helena Neves Pereira Ramalho Rua DECivil, IST, Lisboa, Portugal November 2011

ABSTRACT

Nowadays, the existing information on heritage goes beyond the physical concept. The invention of the internet and the development of information and communication technologies has changed how museum exhibit their collections, how they interact with the public and with the patrimonial object, beyond the simple reproduction of works. Despite the discussion associated with virtual museums, the main advantage of making an object part of a virtual museum is promoting its interpretation within its environment, which is a regular procedure on scientific studies. This thesis aims to reflect on the tridimensional representation of monuments that, due to their character and function, spread out through the territory, which complicates the survey procedure and therefore the elaboration of the digital models. Additionally, the virtual model is intended to allow “visits” in loco. The purpose of the work is to formulate a methodology to be applied in similar cases. It evaluates the potential use of these digital tools, which are based on the association of geometry with alpha numeric metadata. Associative geometry allows the model to automatically adapt to new data, thus avoiding the need for a completely new model with each future update, whenever new information is uncovered. The case study presented is the Águas Livres Aqueduct, National Monument which extends along a vast area of the territory of Lisbon and Tagus Valley.

Keywords: 3D model, associative geometry, digital project.

1. Introduction are dependent processes of the election of values. Heritage is defined as a collection of the works of man in which a community recognizes their specific and particular values and with whom they identify. The identification and valuation of heritage

Nowadays, the conscious identity in its most global sense leads to several initiatives in the interests of preserving heritage.

The concept of virtual museum is a recent phenomenon in the context of museology, where the digital object corresponds to a new type of heritage. For example, the project "Rome Reborn", an international initiative whose aim is to create 3D digital models illustrating the urban context of ancient

Rome,

with

two

purposes:

historical

research (restricted model) and public dissemination (simplified model of generic access). The

monuments

whose

characteristics

extend the territory have not been subjected to major interventions of this kind. The reason for this comes down to extensive process

of model

development, mainly in the survey, both because of its length and sometimes by the existence of technical limitations. It would be crucial the existence of a process

that

could

accelerate

the

data

communication without losing accuracy.

procedure for the preparation of these models based on existing data and occasional surveys in order to make a first model of this type of monuments, though, when necessary are able to be easily and expeditiously edited afterwards. The present model will then be of relevance both in terms of direct work with the aqueduct or on the aspect of works of conservation and future surveys. On the other hand, it will take a more educational aspect of visualization and interaction with the general public in heritage files or even in a virtual museum. With the process developed, and with the use of appropriate software with associative and parametric features, it ends up in a cyclic process of model development that arrives early to the general public (Figure 1). To this end, we seek to evaluate the of

representation

geometry of

in

the

three-dimensional

associative models

of

monuments that stretch across the territory and at the same time their ability to add data.

into account the proposed modeling method.

The objective is the: - Creation of a list of tools and systematic survey and obtaining factual information; - Identification of the major limitations of current

Therefore, this thesis aims to develop a

applicability

Image1. Proposed virtual model development process taking

tools in the survey, especially when implemented in extensive monuments; -

Preparation

of

a

survey

methodology

and

representation of the type of monument in study; - Development of a database; - Systematization of repetitive processes of the initial phase using Scheme programming in order to minimize production errors; - Georeferencing data; - Realization of a digital model, capable of supporting future data additions and be open to visitors after the event. As a case study of an extensive monument, it was chosen the Águas Livres Aqueduct, more precisely its general section, which begins in the Mãe de Água Velha in Belas and ending in Mãe de Água of Amoreiras through five counties, Sintra, Oeiras, Loures Amadora and Lisbon, for a total of 14,200 km (9,000 steps).

2. Heritage In The Digital Age

research sites - which are complemented with graphic and cartographic databases.

Since the first informal attempts, in antiquity, to the present museum created with the specific goal of protecting the movable heritage and educating the public, the museology has adapted and continues to adapt to new realities, as can be seen in generality of the current media.

Communication Technologies) and in particular the Internet, the museum has become a new reality as a result of the introduction of the virtual platform.

well

communication

as

it

regarding the detection of traces is located in a nonsuperficial layer. It does hamper the collection of heritage whose characteristics is buried in length

an

excellent

means

allows

mutually

a

conducts of aqueducts. The geotagging appears here as an auxiliary survey process because it allows overlay data from different sources on the same basis.

The way the museums use the Internet is as

sensing methods, that present some limitations

and extends throughout the territory, such as the

So, with the advent of ICT (Information and

varied,

The archaeology has, direct and indirect, remote

of

greater

interaction with both the public and among experts.

For

the

final

representation

of

an

architectural object it must be taken into account its surroundings as it is also necessary a survey and representation of the land itself.

The type of digital material exposed and how its done has also evolved.

Currently, modeling technologies applied to

The UNESCO Charter for the Preservation of

heritage to obtain 3D models are photogrammetry

Digital Heritage came steer the various existing

and laser scanner, which allows to reproduce reality

developments in this matter, recognizing this new type

by survey, eventually it may be supplemented by

of heritage as well the validation of digital museums.

shaping tools on the construction of the model.

The concern about their heritage and digital preservation is not restricted only to museums, but by an awareness and collective initiative of public and private entities and individuals that together contribute to the safeguarding of international heritage.

The development of parametric drawing tools allowed the emergence of other programs aimed at creating projects in the digital environment, known as BIM (Building Information Modelling).

The memory is a testament to the legacy of

The BIM, in addition of possessing the skills

past generations and leads to the knowledge of

(graphic) of a CA(A)D program (Computer Aided

cultural identity, where the assimilation of the

Architectural Design), depends on the spatial

community has a key role in its preservation and

relationships

protection through education, training, research,

quantities and descriptions of the different elements

science and tourism.

that make up the object. It combines three-

of

parameters

(alphanumeric),

dimensional model to a database that can be 3. Process of compiling an Architectural /

accessed automatically.

Archaeological Register Autodesk Revit it’s a configurable BIM with The digital model is part of an architectural

associative properties, ie enables modeled objects

register. The development of three-dimensional

to be modified, in interactive mode, according to the

model is dependent on the initial phase of data

values assigned to its variables, both in tables and

collection, which in turn stems from a historical and

directly in the model, and try different possible

archaeological approach - literature sources and

solutions. In turn, the associative geometries allow

the establishment of relationships between the

It was necessary to use an orderly process

different components of the same object, which fit

and systematic work where the existing information.

hierarchically according to the changes made to

This information was then processed by multiple

certain elements.

software.

This type of application allows to overcome

In each phase we used appropriate software,

the gaps of the survey phase, since it allows the

including Google Earth, Microsoft Excel and Autodesk

model to be supplemented at any time by updating

Autocad, Arcgis, Blender and Revit (Figure 2).

individual entities or groups of entities without having Autodesk Revit presents itself as the key

to completely redo the model.

software because it enables the creation of the 3D model 4. Case Study

associative

and

parametric

with

an

associated database. Blender, in turn, is the software that makes

Each monument has its own important and detailed characteristics. It is necessary to take into account

viewing and consequently the interaction between the virtual model and the general public.

both the typology of the features or specifications of particular cases when it comes to the approach

The

remaining

intermediate

auxiliary

software’s are important to obtain the final object.

methodology to the characterization of the elements of the monument in question. In this way, it allows to parameterize the general elements of the case study - Aqueduct such as the barrel, the turrets and the wall with their bows, and follow the same procedure to the special elements: angular towers (with the particularity of suffering a range of rotation angle and to adapt to different orientations of the barrel), ogival arches

Image 2. Work sequence developed in the present

and other joints.

model. The process described below generalizes

The process was systematized into five

and systematizes the method for obtaining and

fundamental sequential phases: data collection, data

reporting data on the monuments that are extended

processing, architectural survey, digital modeling

in space and time for future representations.

and virtual modeling. These are materialized by drawing the line of travel of the Aqueduct, the

1º. Data Acquisition

parameterization of families, the modeling of land and conversion of the model for virtual support.

It’s the gathering of all the available and relevant

The information collected is very important for the development of the final model. The data derived from geographical

the following sources: mapping, survey,

technical drawings.

photographic

survey

and

evidence to the preparation of the monument in study. It is very important to have details of the project, as well as photographs and cartographic elements. In the absence of any of these elements, it is important to predict its development even with an approximate degree of accuracy.

As this methodology was designed precisely for

important to invest a little time learning the program,

such cases, i.e. so that the model can be updated

in order to plan in advance the most expedient

easily and expeditiously as the data is being

method of creating the elements, before moving to

acquired, the problem of rigor in the materialization

its development.

of information is naturally cautious.

Thus, it is possible to have a model that supports all

At this stage it is advisable to use Google Earth

the changes to be imposed.

and Excel as an aid to work. 5º. Virtual modeling 2º. Survey After finishing the modeling, the model is It is important to carry out surveys so that you

implemented in a program of three-dimensional

can continue the process even when the collected

visualization and interaction that may allow its use in

information is inhibitive to the elaborating of the

real time, with some level of immersion, where it’s

generic model.

applied materials, textures and shadows. This phase allows the musealization of the

3º. Treatment of data

monument in question, making it available to the general public.

After the collection phase and possible punctual surveys, the data is processed, both for developing

5. conclusion

of the monument model as the land and its surroundings. For better accuracy of the final results it is important to entangle all information, especially regarding the location of elements by local sampling.

The heritage consciousness and the consequent preservation of heritage monuments must begin with each person. The creation of digital models is important because it corresponds well to an

Taking into account the development of monuments of great extent, it is crucial to create the structural axis, since all the modeling is dependent on it. This requires that all points are identified (numbered and / or appointed) and properly referenced.

environment of public and private entities, such as universities

and

institutions

of

socio-cultural

responsibility, which enable the development of models suitable for the formulation of leading research to the protection of heritage. But this is not enough to create the models, there must be specific local file access and disclosure of databases and it’s

At this stage, it is advisable to use georeferenced

programs

and

a

CAD

where museums have an important role.

program

associated with programming language so it can be used programs created in the Scheme language, as it automates the repetitive and time consuming process that could lead to random errors.

The

monuments

in

extension

are

at

a

disadvantage in this transition to the virtual museum acquisition, because they generate a larger effort on the lengthy process of survey to which they need to submit. Reason why the development of models with

4º. Three-dimensional modeling

isolated elements, i.e. the monuments very well defined and contained was favored at the expense

At this stage it is convenient to use a program BIM with parametric and associative capability. It is

of monuments that extend in space and time. This thesis finds its relevance in this particular point,

taking advantage of this apparent drawback as an

Finally, the experimentation

of

the model

added value by developing a methodology that

revealed the advantage of using new technologies

provides everything for the recreation of objects that

for viewing / manipulation, including game engines,

can be applied to future models, which can then be

which allow greater immersion and realism of the

used either by technicians either by the general

object exposed, visual quality and real-time.

public.

This methodology is based on the software with parametric and associative properties which allows automatic model updating and modifying much easily and expeditiously. However there is the awareness that the modeling programs adopted, as well as all existing, have limitations that must be overcome to reach the desired product, and sometimes it is needed to make concessions so that there is consistency in the generated information.

The programming languages make the process more efficient, avoiding unnecessary time, detaching user from routine tasks. If this communication software was developed, this type of procedure, that was applied in the present work in the generation of the axis director of the model, could well be extended and implemented to the next stage of interaction with the BIM software. Thus, the whole process of preparing the three-dimensional model would be made by recourse to a programming language. However, given that the model is intended to be handled by technical heritage experts, it was considered that it would be more practical the use of BIM at the expense of a fully automated, once you lose the interactive portion and editing elements and its very selective view of informative tables.

Nevertheless, it is considered that the program used, and as the model designed, produced the desired result. In the sense that it has developed a digital model useful for the technicians use in the management, protection and maintenance of the monument: as a virtual model that allows the public to interact in an educational and fun way.

Future Developments

The digital model has generated widespread use, by EPAL technical, management, preservation and maintenance of the Aqueduct.

The main advantage of the model now created is the chance to let edit and adapt to new sprites specific data that may be obtained as the correct location and sizing of elements of the aqueduct are being known, without having to redo the whole process from the beginning. Updating the model could be implemented successively, until they reach the level of rigor appropriate to the scientific requirements, and if the area surrounding the monument is also considered for modeling, as conducted in this study it can be provided with a tool to consider in its the design and architecture of urban

planning,

which

will

develop

in

the

surrounding area. In turn, the works are complemented by field photogrammetric surveys and / or partial digital scanning,

to

obtain

the

most

representative

components stereo to my of the monument, these images can be used to increase the level of detail of the surface to finish of the model and to replace the current texturing process by use of standard images.

Once the virtual model has the potential to come to the collection of the Museum of Water, it can be used on the creation of by-products, resulting from the simplification of the base model that require less computing resources so it can be more easily manipulated. This type of models, summarized and statistically more didactic function, are extremely suitable to be integrated into national systems to support

the

scientific

community,

such

as

Endovélico whose mission may be extended to cover also the centralization of information on the simplified models in order to disseminate interactive monuments. The methodology developed in this work can be used as an aid to future representations of monuments in length, providing the conversion of such heritage to the new existing reality - virtual reality - in parallel with the proliferation of the use of these new tools allowed because of the greater software capacity. This allows us to foresee the potential

application

of

emerging

technologies

rendering engines of video games on simulations of heritage, enjoying its high performance and realistic rendering capabilities. Finally, there would be a greater advantage in the development of interaction between software, which would automate and streamline the whole process even more, as well improve the current BIM tools and their associative properties. 6.

References

[1] BRØNNUM, Rasmus – “Associative design at berlage”. Agosto de 2007. Disponível em: http://rasmusbroennum.wordpress.com/2007/08/19/associativ e-design/ (25-01-2011) [2] CHOAY, Françoise – Alegoria do património. Lisboa: Ed. 70, 1999. [3] HENRIQUES, Rosali – “Museus virtuais e cibermuseus: a internet e os museus”. Memória, museologia e virtualidade: um estudo sobre o Museu Pessoa. Lisboa: Universidade Lusófona de Humanidades e Tecnologia, 2004. [4] KOLAREVIC, Branko – Architecture in the digital age : design and manufacturing. New York : Spon Press, 2003. [5] MATEUS, Luís – “A conservação do património arquitectónico e as novas Metodologias de documentação baseadas na Fotogrametria e na digitalização laser “ in Mestrado em Arquitetura e Reabilitação Urbana. Lisboa: FAUTL, Maio 2011. [6] PEREIRA, Zulmira – Elaboração de um Arquivo Arquitectónico inserido

num

Modelo

Tridimensional

Urbano.

Lisboa:

Faculdade de Ciências da Universidade do Porto, Setembro de 2003. [7] UNESCO – Carta para a Preservação do Património Digital. Paris: UNESCO, 2003. http://www.romereborn.virginia.edu/rome_reborn_2_documents/

Images 2. - 8. Images of the generated model.