Cumincad : CUMINCAD Papers : Search Results

CumInCAD is a Cumulative Index about publications in Computer Aided Architectural Design
supported by the sibling associations ACADIA, CAADRIA, eCAADe, SIGraDi, ASCAAD and CAAD futures

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_id	c19c
authors	Beliveau, Y.J.
year	1996
title	What can real-time positioning do for construction?
source	Automation in Construction 5 (2) (1996) pp. 79-89
summary	New technologies are now available that can rapidly measure three-dimensional coordinates of objects. The integration of these fast 3-D Real-time Position Measurement (D-RtPM) devices and CAD (3D-RtPM/CAD) technologies can be viewed as a better tool for surveyors or as a means to change the most fundamental concepts of the construction industry. 3D-RtPM/CAD is a better surveying tool; however, 3D-RtPM/CAD as the basis for fundamental change within the construction industry is the issue.There are several potential technologies that can provide real-time position measurement. This paper will limit presentation to two of these. The first is based on recent developments in Global Positioning Systems. The second is a new laser-based product, OdysseyTM (Odyssey is a trademark of Spatial Positioning Systems, Inc.). Odyssey received the NOVA award in March, 1995 because of its recognized performance enhancement to the construction industry. These positioning systems provide the capability for equipment and crafts people to view the project from a graphical representation in which they see their position interactively updated. Potential benefits to the construction industry are presented. The research needed achieving maximum benefits of these systems is also presented.
series	journal paper
more	http://www.elsevier.com/locate/autcon
last changed	2003/05/15 21:22

_id	7670
authors	Sawicki, Bogumil
year	1995
title	Ray Tracing – New Chances, Possibilities and Limitations in AutoCAD
source	CAD Space [Proceedings of the III International Conference Computer in Architectural Design] Bialystock 27-29 April 1995, pp. 121-136
summary	Realistic image synthesis is nowadays widely used in engineering applications. Some of these applications, such as architectural, interior, lighting and industrial design demand accurate visualization of non-existent scenes as they would look to us, when built in reality. This can only be archived by using physically based models of light interaction with surfaces, and simulating propagation of light through an environment. Ray tracing is one of the most powerful techniques used in computer graphics, which can produce such very realistic images. Ray tracing algorithm follows the paths of light rays backwards from observer into the scene. It is very time consuming process and as such one could not be developed until proper computers appeared, In recent years the technological improvements in computer industry brought more powerful machines with bigger storage capacities and better graphic devices. Owing to increasing these hardware capabilities successful implementation of ray tracing in different CAD software became possible also on PC machines. Ray tracing in AutoCAD r.12 - the most popular CAD package in the world - is the best of that example. AccuRender and AutoVision are an AutoCAD Development System (ADS) applications that use ray tracing to create photorealistic images from 3D AutoCAD models. These ,internal"' applications let users generate synthetic images of threedimensional models and scenes entirely within AutoCAD space and show effects directly on main AutoCAD screen. Ray tracing algorithm accurately calculates and displays shadows, transparency, diffusion, reflection, and refraction from surface qualities of user-defined materials. The accurate modelling of light lets produce sophisticated effects and high-quality images, which these ray tracers always generates at 24-bit pixel depth,"providing 16,7 million colours. That results can be quite impressive for some architects and are almost acceptable for others but that coloured virtual world, which is presented by ray tracing in AutoCAD space in such convincing way, is still not exactly the same as the real world. Main limitations of realism are due to the nature of ray tracing method Classical ray tracing technique takes into account the effects of light reflection from neighbouring surfaces but, leaves out of account the ambient and global illumination arising out of complex interreflections in an environment. So models generated by ray tracing belong to an "ideal" world where real materials and environment can't find their right place. We complain about that fact and say that ray tracing shows us "too specular world", but (...) (...) there is anything better on the horizon? It should be concluded, that typical abilities of today's graphics software and hardware are far from exploited. As was observed in literature there have been various works carried along with the explicit intention of overcoming all these ray tracing limitations, These researches seem to be very promising and let us hope that their results will be seen in CAD applications soon. As it happens with modelling, perhaps the answer will come from a variety of techniques that can be combined together with ray tracing depending on the case we are dealing with. Therefore from the point of view of an architects that try to keep alive some interest on the nature of materials and their interaction with form, "ray tracing" seems to be right path of research and development that we can still a long way follow, From the point of view of the school, a critical assimilation of "ray tracing" processes is required and one that might help to determinate exactly their distortions and to indicate the correct way of its development and right place in CAAD education. I trust that ray tracing will become standard not only in AutoCAD but in all architectural space modelling CAD applications and will be established as a powerful and real tool for experimental researches in architectural design process. Will be the technological progress so significant in the nearest future as it is anticipated?
series	plCAD
last changed	2000/01/24 10:08

_id	bf5f
authors	Chen, Xiangping
year	1995
title	Representation, Evaluation and Edition of Feature-based and Constraint- based Design
source	Purdue University
summary	This thesis investigates a general and systematic approach to feature-based and constraint-based design. We combine feature-based design and constraint-based design by globally decomposing a design into a sequence of feature attachments and locally defining and positioning each feature by constraints. Analogous to the concept of high-level programming languages, we formalize a layered design model that eliminates the dependency of a design representation on a solid modeler. With this design model, design intent, such as feature descriptions and constraints, is stored in an unevaluated, modeler-independent design representation while the geometry to which it corresponds is stored in an evaluated, modeler-dependent design representation. The separation essentially relies on a naming and matching schema that converts between a geometric reference and a generic name, and a design compiler that automatically instantiates the unevaluated design representation to an evaluated design representation with respect to a solid modeler. The geometric references for defining feature attributes and constraints are recorded with their generic names in the unevaluated design representation. We propose several techniques for naming geometric entities unambiguously. The design compilation or instantiation involves remapping a generic name back to a geometric reference in the selected geometric modeler, solving constraints and implementing feature operations or attachments. Instead of developing a constraint solver for this design compiler, we use an independent and general solver. Feature attachment operations are different from classical Boolean operations in solid modeling. However, we provide a semantics for them that is based on existing operations in solid modeling. The layered design model allows users to edit archived conceptual designs to derive new designs quickly. We investigate the coordination of later features in the unevaluated and modeler-independent representation when a feature is edited and provide a method for editing feature-based and constraint-based design. We also discuss how to extend this work to a commercial feature-based and constraint-based CAD system.
series	thesis:PhD
last changed	2003/02/12 22:37

_id	1a52
authors	Amor, R., Augenbroe, G., Hosking, J., Rombouts and W., Grundy, J.
year	1995
title	Directions in modelling environments
source	Automation in Construction 4 (3) (1995) pp. 173-187
summary	Schema definition is a vital component in the computerised A/E/C projects. existing tools to manage this task are limited both in terms of the scope Of problems they can tackle and their integration with each other. This paper describes a global modellling and development environment for large modelling projects. This environment provides a total solution from initial design of schemas to validation, manipulation arid navigation through final models. A major benefit of the described system is the ability to provide multiple views of evolving schemas (or models) in both graphical and textual forms This allows modellers to visualise their schemas and instance models either textually or graphically as desired. The system automatically maintains the Conisistency of the informalion in these views even when modifications are made in other views. Simple and intuitive view navigation methods allow required information to he rapidly accessed. The environment supports strict checking of model instances and schemas in one of the major ISO-standardised modelling languages no used in product data technology. Ill this paper we show how such a modelling environment has been constructed for evaluation in the JOULE founded COMBINE project.
keywords	Modelling Environment; Consistency; Multiple Views: Views; Building Models; Information Management; Integrated System; Product Modelling
series	journal paper
email
more	http://www.elsevier.com/locate/autcon
last changed	2003/05/15 14:33

_id	c642
authors	Andersen, T. and Carlsen, N.V.
year	1995
title	Software design of maintainable knowledge-based systems for building design
source	Automation in Construction 4 (2) (1995) pp. 101-110
summary	Identifying and establishing a basic structure for knowledge representation is one of the keys to successful design of knowledge-based computer systems. In Building Design and Construction, this initial knowledge structure can be achieved by utilizing a query driven approach to software engineering. As (user) queries reflect the user's demand for in/output, it is natural to link the overall user dialogue with key elements in the knowledge base direct connections between user screen and objects in the knowledge base support prototyping and testing the application during development. However, the price for pursuing this approach in its pure form can be high, as needs for later maintenance and augmentation of the system can be very hard to fulfill. To overcome these problems, a strict user interlace, software separation strategy must be. introduced at early stages of software design. and implemented as a global control module as independent of the knowledge processing as possible.
keywords	Knowledge-based; Query driven: Software design; User interlace: Separation; Maintainable systems
series	journal paper
more	http://www.elsevier.com/locate/autcon
last changed	2003/06/02 09:35

_id	7a20
id	7a20
authors	Carrara, G., Fioravanti, A.
year	2002
title	SHARED SPACE’ AND ‘PUBLIC SPACE’ DIALECTICS IN COLLABORATIVE ARCHITECTURAL DESIGN.
source	Proceedings of Collaborative Decision-Support Systems Focus Symposium, 30th July, 2002; under the auspices of InterSymp-2002, 14° International Conference on Systems Research, Informatics and Cybernetics, 2002, Baden-Baden, pg. 27-44.
summary	The present paper describes on-going research on Collaborative Design. The proposed model, the resulting system and its implementation refer mainly to architectural and building design in the modes and forms in which it is carried on in advanced design firms. The model may actually be used effectively also in other environments. The research simultaneously pursues an integrated model of the: a) structure of the networked architectural design process (operators, activities, phases and resources); b) required knowledge (distributed and functional to the operators and the process phases). The article focuses on the first aspect of the model: the relationship that exists among the various ‘actors’ in the design process (according to the STEP-ISO definition, Wix, 1997) during the various stages of its development (McKinney and Fischer, 1998). In Collaborative Design support systems this aspect touches on a number of different problems: database structure, homogeneity of the knowledge bases, the creation of knowledge bases (Galle, 1995), the representation of the IT datum (Carrara et al., 1994; Pohl and Myers, 1994; Papamichael et al., 1996; Rosenmann and Gero, 1996; Eastman et al., 1997; Eastman, 1998; Kim, et al., 1997; Kavakli, 2001). Decision-making support and the relationship between ‘private’ design space (involving the decisions of the individual design team) and the ‘shared’ design space (involving the decisions of all the design teams, Zang and Norman, 1994) are the specific topic of the present article. Decisions taken in the ‘private design space’ of the design team or ‘actor’ are closely related to the type of support that can be provided by a Collaborative Design system: automatic checks performed by activating procedures and methods, reporting of 'local' conflicts, methods and knowledge for the resolution of ‘local’ conflicts, creation of new IT objects/ building components, who the objects must refer to (the ‘owner’), 'situated' aspects (Gero and Reffat, 2001) of the IT objects/building components. Decisions taken in the ‘shared design space’ involve aspects that are typical of networked design and that are partially present in the ‘private’ design space. Cross-checking, reporting of ‘global’ conflicts to all those concerned, even those who are unaware they are concerned, methods for their resolution, the modification of data structure and interface according to the actors interacting with it and the design phase, the definition of a 'dominus' for every IT object (i.e. the decision-maker, according to the design phase and the creation of the object). All this is made possible both by the model for representing the building (Carrara and Fioravanti, 2001), and by the type of IT representation of the individual building components, using the methods and techniques of Knowledge Engineering through a structured set of Knowledge Bases, Inference Engines and Databases. The aim is to develop suitable tools for supporting integrated Process/Product design activity by means of a effective and innovative representation of building entities (technical components, constraints, methods) in order to manage and resolve conflicts generated during the design activity.
keywords	Collaborative Design, Architectural Design, Distributed Knowledge Bases, ‘Situated’ Object, Process/Product Model, Private/Shared ‘Design Space’, Conflict Reduction.
series	other
type	symposium
email
last changed	2005/03/30 16:25

_id	6279
id	6279
authors	Carrara, G.; Fioravanti, A.
year	2002
title	Private Space' and ‘Shared Space’ Dialectics in Collaborative Architectural Design
source	InterSymp 2002 - 14th International Conference on Systems Research, Informatics and Cybernetics (July 29 - August 3, 2002), pp 28-44.
summary	The present paper describes on-going research on Collaborative Design. The proposed model, the resulting system and its implementation refer mainly to architectural and building design in the modes and forms in which it is carried on in advanced design firms. The model may actually be used effectively also in other environments. The research simultaneously pursues an integrated model of the: a) structure of the networked architectural design process (operators, activities, phases and resources); b) required knowledge (distributed and functional to the operators and the process phases). The article focuses on the first aspect of the model: the relationship that exists among the various ‘actors’ in the design process (according to the STEP-ISO definition, Wix, 1997) during the various stages of its development (McKinney and Fischer, 1998). In Collaborative Design support systems this aspect touches on a number of different problems: database structure, homogeneity of the knowledge bases, the creation of knowledge bases (Galle, 1995), the representation of the IT datum (Carrara et al., 1994; Pohl and Myers, 1994; Papamichael et al., 1996; Rosenmann and Gero, 1996; Eastman et al., 1997; Eastman, 1998; Kim, et al., 1997; Kavakli, 2001). Decision-making support and the relationship between ‘private’ design space (involving the decisions of the individual design team) and the ‘shared’ design space (involving the decisions of all the design teams, Zang and Norman, 1994) are the specific topic of the present article. Decisions taken in the ‘private design space’ of the design team or ‘actor’ are closely related to the type of support that can be provided by a Collaborative Design system: automatic checks performed by activating procedures and methods, reporting of 'local' conflicts, methods and knowledge for the resolution of ‘local’ conflicts, creation of new IT objects/ building components, who the objects must refer to (the ‘owner’), 'situated' aspects (Gero and Reffat, 2001) of the IT objects/building components. Decisions taken in the ‘shared design space’ involve aspects that are typical of networked design and that are partially present in the ‘private’ design space. Cross-checking, reporting of ‘global’ conflicts to all those concerned, even those who are unaware they are concerned, methods for their resolution, the modification of data structure and interface according to the actors interacting with it and the design phase, the definition of a 'dominus' for every IT object (i.e. the decision-maker, according to the design phase and the creation of the object). All this is made possible both by the model for representing the building (Carrara and Fioravanti, 2001), and by the type of IT representation of the individual building components, using the methods and techniques of Knowledge Engineering through a structured set of Knowledge Bases, Inference Engines and Databases. The aim is to develop suitable tools for supporting integrated Process/Product design activity by means of a effective and innovative representation of building entities (technical components, constraints, methods) in order to manage and resolve conflicts generated during the design activity.
keywords	Collaborative Design, Architectural Design, Distributed Knowledge Bases, ‘Situated’ Object, Process/Product Model, Private/Shared ‘Design Space’, Conflict Reduction.
series	other
type	symposium
email
last changed	2012/12/04 07:53

_id	47c7
authors	Fasse, Isabelle and Paul, Jean Claude
year	1995
title	Realistic Rendering and Computer-Aided Lighting Design in Architecture
source	Sixth International Conference on Computer-Aided Architectural Design Futures [ISBN 9971-62-423-0] Singapore, 24-26 September 1995, pp. 241-255
summary	This paper presents an application of realistic rendering to computer aided design in architecture. The application concerns lighting design of buildings. We describe a library of algorithms which allows the simulation of the light sources emittance, surfaces reflectance/transmittance, and light propagation laws. Our general algorithm can compute a physically based simulation of illumination in complex geometric models and offers the capability to change the inputs without recalculating the entire global physical solution. Since the solution is view independent, hardware graphic accelerations are then used to generate the images. Two industrial experimentations have proved that our system can help designers to evaluate small iterations in the design, as well as compare global alternative solutions. Therefore, design quality improvement can be obtained while saving the costly full scale trials that are necessary when conventional methods are used.
keywords	Computer-Aided Design, Computer Graphics, Synthesis Images, Architectural Design, Lighting Engineering
series	CAAD Futures
last changed	1999/08/03 17:16

_id	1886
authors	Rychter, Zenon
year	1995
title	Matematical Architectural Syntesis
source	CAD Space [Proceedings of the III International Conference Computer in Architectural Design] Bialystock 27-29 April 1995, pp. 283-297
summary	Extremes converge. Life blossoms on the boundary. All creative thinking, architectural or mathematical, is essentially the some. Today legions of dull computers take over the role of renaissance giants in integrating all ways of thinking. On the sensual level, computer art is often indistinguishable from computer simulations of physical processes, such as fractals representing chaos. On the logical level, all information boils down to the language of bits, sequences of O's and I's or X's and Y's if you like- there just has to be two of them, like Adam and Eve at the beginning of mankind. Creating means synthesizing, composing, constructing a whole from elements. But often the starting point, the finish, the middle stages and methods are fuzzy, vague, ill- defined-ore all yet to be discovered or conceived. It is like groping in a dark labyrinth, searched and created at the same time. There are many branches to discover and explore, many dead ends forcing retreat, no guarantee of a solution, and even no clear idea of what a solution might be. It is a trial- and-error, generate-and-test, back-and-forth, top-down and bottom-up, global and local, inductive and deductive, rigorous at times and fuzzy most of the time, ameba-like process or bunch of processes. In this, creative, perspective both architecture and mathematics become experimental sciences: as such they require laboratories. Computer systems (hardware plus software) supply today the necessary environment, ways and means. To the happy user of a general-purpose platform, straddling the architecture-mathematics boundary-with one leg on a general-purpose computer-aided design system, like AutoCAD, and the other leg on a general-purpose mathematical system, like Mathematica, the essential unity of creatively doing both architecture and mathematics is hard to overlook.
series	plCAD
last changed	2000/01/24 10:08

_id	b633
authors	Tan, Milton and Teh, Robert (Eds.)
year	1995
title	The Global Design Studio [Conference Proceedings]
source	Sixth International Conference on Computer-Aided Architectural Design Futures [ISBN 9971-62-423-0] Singapore, 24-26 September 1995, 779 p.
summary	1995 marks the 10th anniversary of the CAAD Futures series of international conferences which is dedicated to "promoting (...) the advancement of computer-aided architectural design in the service of those concerned with the quality of the built environment". It also marks the first time this important forum is held in Asia; hosted by the School of Architecture, National University of Singapore. This proceedings is a compilation of the sixty nine papers which were selected by an International Review Committee and presented at the conference in Singapore on 24-26 September 1995. The Chapters are organised according to the themes covered by the conference -Electronic Design Media, Environmental Simulation & Decision Support, Generative Systems, Scene and Product Modelling, Virtual Reality, Information Delivery Systems & Geographic Information Systems, Shape Grammar, Recognition & Emergence, Precedence & Prototypes, Case-based Reasoning, and Cooperative Design.
series	CAAD Futures
email
last changed	2003/05/16 20:58

_id	0611
authors	Ward, Gregory J.
year	1995
title	Making global illumination user-friendly
source	Eurographics Workshop on Rendering
summary	Global illumination researchers tend to think in terms of mesh density and sampling frequency, and their software reflects this in its user interface. Advanced rendering systems are rife with long command lines and parameters for tuning the sample densities, thresholds and other algorithm-specific variables, and the novice user is quickly lost in a sea of possibilities. This paper details a successful effort of making one such global illumination system usable by people who understand their problems, even if they do not understand the methods needed to solve them, through an assisted oracle approach. A single program is introduced to map a small set of intuitive control variables to the rendering commands and parameter settings needed to produce the desired output in a reasonable time. This new executive program then serves as the basis for a graphical user interface that is both friendly in its appearance and reliable in its performance. Finally, we conclude with some future directions for improving this interface.
series	other
last changed	2003/04/23 15:50

_id	ijac20032101
id	ijac20032101
authors	Koutamanis, Alexander
year	2004
title	CAAD's Seven Arguable Virtues
source	International Journal of Architectural Computing vol. 2 - no. 1
summary	In 1995 Maver proposed seven deadly sins for CAAD as the prelude to a critical discussion on the principles, methods and practices of the field. In an attempt to return to this discussion, in this paper these sins are linked to the seven deadly sins and the complementary seven heavenly virtues. The analysis of computational processes into a theoretic, an algorithmic and an implementational framework provides a framework for the positioning of sins and possible or already attained virtues in CAAD.
series	journal
email
more	http://www.multi-science.co.uk/ijac.htm
last changed	2007/03/04 07:08

_id	0bbb
authors	Alshawi, Mustafa
year	1995
title	Dynamic Generation of Design Plans at the Brief Stage
source	Sixth International Conference on Computer-Aided Architectural Design Futures [ISBN 9971-62-423-0] Singapore, 24-26 September 1995, pp. 219-228
summary	The traditional approach to design and construction suffers from many limitations. As the technology becomes more available to the average users, the need for an effective and efficient solution has never been greater. This paper introduces an alternative approach to the life cycle of construction projects "application controlled process". Based on this approach, a framework for an Integrated Construction Environment (ICE) has been developed and implemented in a prototype demonstrator "SPACE" (Simultaneous Prototyping for An integrated Construction Environment). This paper is only concerns with those parts of the ICE which are relevant to the dynamic generation of design drawings. The NIRMANI system aims at generating a schematic design by retrieving previous design solutions that match the problem specification from a multimedia case library. While the Bay Design Systems aims at re-adjusting the produced design solution to minimise construction problems.
keywords	Integrated Environments, Case-Based Design, Project Life Cycle, Integrated Construction Environment
series	CAAD Futures
email
last changed	2003/11/21 15:15

_id	00e7
authors	Bushby, S.T.
year	1997
title	BACnetTM: a standard communication infrastructure for intelligent buildings
source	Automation in Construction 6 (5-6) (1997) pp. 529-540
summary	Intelligent buildings require integration of a variety of computer-based building automation and control system products that are usually made by different manufacturers. The exchange of information among these devices is critical to the successful operation of the building systems. Proprietary approaches to providing this communication have created great challenges for system integrators and hampered the development of intelligent building technology. Even though digital automation and control technology has been widely available for more than a decade and islands of automation are common, intelligent buildings with integrated building services are still more of a promise than a reality. BACnetTM is a standard communication protocol for building automation and control networks developed by the American Society of Heating, Refrigerating and Air-conditioning Engineers (ASHRAE, Standard 135-1995: BACnetTM--A Data Communication Protocol for Building Automation and Control Networks. American Society of Heating, Refrigerating, and Air-conditioning Engineers. Atlanta, Georgia, USA, 1995). BACnetTM provides the communication infrastructure needed to integrate products made by different vendors and to integrate building services that are now independent. This paper describes the main features of the BACnetTM protocol and early experience implementing it.
series	journal paper
more	http://www.elsevier.com/locate/autcon
last changed	2003/05/15 21:22

_id	a036
authors	Ervin, Stephen and Westort, Caroline
year	1995
title	Procedural Terrain: A Virtual Bulldozer
source	Sixth International Conference on Computer-Aided Architectural Design Futures [ISBN 9971-62-423-0] Singapore, 24-26 September 1995, pp. 257-265
summary	We describe a system for procedural landform design, which uses the simple metaphor of a two-dimensional profile or Çbladeë, swept along a three-dimensional trajectory, or Çpathë, leaving behind a modeled surface in its wake. This Çpathë and Çbladeë system can mimic a common bulldozer ñ a simple rectangular blade moved along a path constrained to straight lined and large radius curves ñ as well as more fanciful landform designs ñ a blade of continually changing profile swept along an exponential spiral path, for instance. Our prototype Çbulldozerë (implemented in AutoLisp) operates in a field of procedurally defined landform Çprimitivesë to create a virtual surface, and uses a standard rectangular mesh for displaying the resultant landform.
keywords	Digital Terrain Model, Procedural Model, Landscape Design, Landform
series	CAAD Futures
last changed	1999/08/03 17:16

_id	2068
authors	Frazer, John
year	1995
title	AN EVOLUTIONARY ARCHITECTURE
source	London: Architectural Association
summary	In "An Evolutionary Architecture", John Frazer presents an overview of his work for the past 30 years. Attempting to develop a theoretical basis for architecture using analogies with nature's processes of evolution and morphogenesis. Frazer's vision of the future of architecture is to construct organic buildings. Thermodynamically open systems which are more environmentally aware and sustainable physically, sociologically and economically. The range of topics which Frazer discusses is a good illustration of the breadth and depth of the evolutionary design problem. Environmental Modelling One of the first topics dealt with is the importance of environmental modelling within the design process. Frazer shows how environmental modelling is often misused or misinterpreted by architects with particular reference to solar modelling. From the discussion given it would seem that simplifications of the environmental models is the prime culprit resulting in misinterpretation and misuse. The simplifications are understandable given the amount of information needed for accurate modelling. By simplifying the model of the environmental conditions the architect is able to make informed judgments within reasonable amounts of time and effort. Unfortunately the simplications result in errors which compound and cause the resulting structures to fall short of their anticipated performance. Frazer obviously believes that the computer can be a great aid in the harnessing of environmental modelling data, providing that the same simplifying assumptions are not made and that better models and interfaces are possible. Physical Modelling Physical modelling has played an important role in Frazer's research. Leading to the construction of several novel machine readable interactive models, ranging from lego-like building blocks to beermat cellular automata and wall partitioning systems. Ultimately this line of research has led to the Universal Constructor and the Universal Interactor. The Universal Constructor The Universal Constructor features on the cover of the book. It consists of a base plug-board, called the "landscape", on top of which "smart" blocks, or cells, can be stacked vertically. The cells are individually identified and can communicate with neighbours above and below. Cells communicate with users through a bank of LEDs displaying the current state of the cell. The whole structure is machine readable and so can be interpreted by a computer. The computer can interpret the states of the cells as either colour or geometrical transformations allowing a wide range of possible interpretations. The user interacts with the computer display through direct manipulation of the cells. The computer can communicate and even direct the actions of the user through feedback with the cells to display various states. The direct manipulation of the cells encourages experimentation by the user and demonstrates basic concepts of the system. The Universal Interactor The Universal Interactor is a whole series of experimental projects investigating novel input and output devices. All of the devices speak a common binary language and so can communicate through a mediating central hub. The result is that input, from say a body-suit, can be used to drive the out of a sound system or vice versa. The Universal Interactor opens up many possibilities for expression when using a CAD system that may at first seem very strange.However, some of these feedback systems may prove superior in the hands of skilled technicians than more standard devices. Imagine how a musician might be able to devise structures by playing melodies which express the character. Of course the interpretation of input in this form poses a difficult problem which will take a great deal of research to achieve. The Universal Interactor has been used to provide environmental feedback to affect the development of evolving genetic codes. The feedback given by the Universal Interactor has been used to guide selection of individuals from a population. Adaptive Computing Frazer completes his introduction to the range of tools used in his research by giving a brief tour of adaptive computing techniques. Covering topics including cellular automata, genetic algorithms, classifier systems and artificial evolution. Cellular Automata As previously mentioned Frazer has done some work using cellular automata in both physical and simulated environments. Frazer discusses how surprisingly complex behaviour can result from the simple local rules executed by cellular automata. Cellular automata are also capable of computation, in fact able to perform any computation possible by a finite state machine. Note that this does not mean that cellular automata are capable of any general computation as this would require the construction of a Turing machine which is beyond the capabilities of a finite state machine. Genetic Algorithms Genetic algorithms were first presented by Holland and since have become a important tool for many researchers in various areas.Originally developed for problem-solving and optimization problems with clearly stated criteria and goals. Frazer fails to mention one of the most important differences between genetic algorithms and other adaptive problem-solving techniques, ie. neural networks. Genetic algorithms have the advantage that criteria can be clearly stated and controlled within the fitness function. The learning by example which neural networks rely upon does not afford this level of control over what is to be learned. Classifier Systems Holland went on to develop genetic algorithms into classifier systems. Classifier systems are more focussed upon the problem of learning appropriate responses to stimuli, than searching for solutions to problems. Classifier systems receive information from the environment and respond according to rules, or classifiers. Successful classifiers are rewarded, creating a reinforcement learning environment. Obviously, the mapping between classifier systems and the cybernetic view of organisms sensing, processing and responding to environmental stimuli is strong. It would seem that a central process similar to a classifier system would be appropriate at the core of an organic building. Learning appropriate responses to environmental conditions over time. Artificial Evolution Artificial evolution traces it's roots back to the Biomorph program which was described by Dawkins in his book "The Blind Watchmaker". Essentially, artificial evolution requires that a user supplements the standard fitness function in genetic algorithms to guide evolution. The user may provide selection pressures which are unquantifiable in a stated problem and thus provide a means for dealing ill-defined criteria. Frazer notes that solving problems with ill-defined criteria using artificial evolution seriously limits the scope of problems that can be tackled. The reliance upon user interaction in artificial evolution reduces the practical size of populations and the duration of evolutionary runs. Coding Schemes Frazer goes on to discuss the encoding of architectural designs and their subsequent evolution. Introducing two major systems, the Reptile system and the Universal State Space Modeller. Blueprint vs. Recipe Frazer points out the inadequacies of using standard "blueprint" design techniques in developing organic structures. Using a "recipe" to describe the process of constructing a building is presented as an alternative. Recipes for construction are discussed with reference to the analogous process description given by DNA to construct an organism. The Reptile System The Reptile System is an ingenious construction set capable of producing a wide range of structures using just two simple components. Frazer saw the advantages of this system for rule-based and evolutionary systems in the compactness of structure descriptions. Compactness was essential for the early computational work when computer memory and storage space was scarce. However, compact representations such as those described form very rugged fitness landscapes which are not well suited to evolutionary search techniques. Structures are created from an initial "seed" or minimal construction, for example a compact spherical structure. The seed is then manipulated using a series of processes or transformations, for example stretching, shearing or bending. The structure would grow according to the transformations applied to it. Obviously, the transformations could be a predetermined sequence of actions which would always yield the same final structure given the same initial seed. Alternatively, the series of transformations applied could be environmentally sensitive resulting in forms which were also sensitive to their location. The idea of taking a geometrical form as a seed and transforming it using a series of processes to create complex structures is similar in many ways to the early work of Latham creating large morphological charts. Latham went on to develop his ideas into the "Mutator" system which he used to create organic artworks. Generalising the Reptile System Frazer has proposed a generalised version of the Reptile System to tackle more realistic building problems. Generating the seed or minimal configuration from design requirements automatically. From this starting point (or set of starting points) solutions could be evolved using artificial evolution. Quantifiable and specific aspects of the design brief define the formal criteria which are used as a standard fitness function. Non-quantifiable criteria, including aesthetic judgments, are evaluated by the user. The proposed system would be able to learn successful strategies for satisfying both formal and user criteria. In doing so the system would become a personalised tool of the designer. A personal assistant which would be able to anticipate aesthetic judgements and other criteria by employing previously successful strategies. Ultimately, this is a similar concept to Negroponte's "Architecture Machine" which he proposed would be computer system so personalised so as to be almost unusable by other people. The Universal State Space Modeller The Universal State Space Modeller is the basis of Frazer's current work. It is a system which can be used to model any structure, hence the universal claim in it's title. The datastructure underlying the modeller is a state space of scaleless logical points, called motes. Motes are arranged in a close-packing sphere arrangement, which makes each one equidistant from it's twelve neighbours. Any point can be broken down into a self-similar tetrahedral structure of logical points. Giving the state space a fractal nature which allows modelling at many different levels at once. Each mote can be thought of as analogous to a cell in a biological organism. Every mote carries a copy of the architectural genetic code in the same way that each cell within a organism carries a copy of it's DNA. The genetic code of a mote is stored as a sequence of binary "morons" which are grouped together into spatial configurations which are interpreted as the state of the mote. The developmental process begins with a seed. The seed develops through cellular duplication according to the rules of the genetic code. In the beginning the seed develops mainly in response to the internal genetic code, but as the development progresses the environment plays a greater role. Cells communicate by passing messages to their immediate twelve neighbours. However, it can send messages directed at remote cells, without knowledge of it's spatial relationship. During the development cells take on specialised functions, including environmental sensors or producers of raw materials. The resulting system is process driven, without presupposing the existence of a construction set to use. The datastructure can be interpreted in many ways to derive various phenotypes. The resulting structure is a by-product of the cellular activity during development and in response to the environment. As such the resulting structures have much in common with living organisms which are also the emergent result or by-product of local cellular activity. Primordial Architectural Soups To conclude, Frazer presents some of the most recent work done, evolving fundamental structures using limited raw materials, an initial seed and massive feedback. Frazer proposes to go further and do away with the need for initial seed and start with a primordial soup of basic architectural concepts. The research is attempting to evolve the starting conditions and evolutionary processes without any preconditions. Is there enough time to evolve a complex system from the basic building blocks which Frazer proposes? The computational complexity of the task being embarked upon is not discussed. There is an implicit assumption that the "superb tactics" of natural selection are enough to cut through the complexity of the task. However, Kauffman has shown how self-organisation plays a major role in the early development of replicating systems which we may call alive. Natural selection requires a solid basis upon which it can act. Is the primordial soup which Frazer proposes of the correct constitution to support self-organisation? Kauffman suggests that one of the most important attributes of a primordial soup to be capable of self-organisation is the need for a complex network of catalysts and the controlling mechanisms to stop the reactions from going supracritical. Can such a network be provided of primitive architectural concepts? What does it mean to have a catalyst in this domain? Conclusion Frazer shows some interesting work both in the areas of evolutionary design and self-organising systems. It is obvious from his work that he sympathizes with the opinions put forward by Kauffman that the order found in living organisms comes from both external evolutionary pressure and internal self-organisation. His final remarks underly this by paraphrasing the words of Kauffman, that life is always to found on the edge of chaos. By the "edge of chaos" Kauffman is referring to the area within the ordered regime of a system close to the "phase transition" to chaotic behaviour. Unfortunately, Frazer does not demonstrate that the systems he has presented have the necessary qualities to derive useful order at the edge of chaos. He does not demonstrate, as Kauffman does repeatedly, that there exists a "phase transition" between ordered and chaotic regimes of his systems. He also does not make any studies of the relationship of useful forms generated by his work to phase transition regions of his systems should they exist. If we are to find an organic architecture, in more than name alone, it is surely to reside close to the phase transition of the construction system of which is it built. Only there, if we are to believe Kauffman, are we to find useful order together with environmentally sensitive and thermodynamically open systems which can approach the utility of living organisms.
series	other
type	normal paper
last changed	2004/05/22 14:12

_id	a8f0
authors	Goel, V.
year	1995
title	Sketches of thought
source	MA: MIT Press, Cambridge
summary	Much of the cognitive lies beyond articulate, discursive thought, beyond the reach of current computational notions. In Sketches of Thought, Vinod Goel argues that the cognitive computational conception of the world requires our thought processes to be precise, rigid, discrete, and unambiguous; yet there are dense, ambiguous, and amorphous symbol systems, like sketching, painting, and poetry, found in the arts and much of everyday discourse that have an important, nontrivial place in cognition. Goel maintains that while on occasion our thoughts do conform to the current computational theory of mind, they often are -- indeed must be - vague, fluid, ambiguous, and amorphous. He argues that if cognitive science takes the classical computational story seriously, it must deny or ignore these processes, or at least relegate them to the realm of the nonmental. As a cognitive scientist with a design background, Goel is in a unique position to challenge cognitive science on its own territory. He introduces design problem solving as a domain of cognition that illustrates these inarticulate, nondiscursive thought processes at work through the symbol system of sketching. He argues not that such thoughts must remain noncomputational but that our current notions of computation and representation are not rich enough to capture them. Along the way, Goel makes a number of significant and controversial interim points. He shows that there is a principled distinction between design and nondesign problems, that there are standard stages in the solution of design problems, that these stages correlate with the use of different types of external symbol systems; that these symbol systems are usefully individuated in Nelson Goodman's syntactic and semantic terms, and that different cognitive processes are facilitated by different types of symbol systems.
series	other
last changed	2003/04/23 15:14

_id	cf40
authors	Leyh, W.
year	1995
title	Automatic assembly of a commercial cavity block system
source	Automation in Construction 4 (2) (1995) pp. 147-167
summary	In an earlier publication (Leyh, 1993) the "Experiences with the Construction of a Building Assembly Robot" have been dealt with. The application of that robot system for the automatic assembly of commercial cavity blocks is the subject of a subsequent report which consists of two parts: in the first, this paper, we primarily deal with the assembly methods, in the second we deal with their realization. What is characteristic of cavity blocks is the fact that they are at first assembled dry, without cementing material, and the masonry is later filled with mortar. As to their weight and dimension, the cavity blocks used by the company GISOTON are adjusted to the ergonomics of a mason. The entirely different characteristics and abilities of assembly robots are not taken into consideration. However, their dimensional tolerance is relatively small (0.5 mm). Furthermore as cavity bricks, they have conic and oval recesses. Both features are strongly favourable for automation. This paper will highlight specific problems during automized construction assembly with commercial standard assembly elements, and help to solve them.
keywords	Robotics; Assembly methods; Jointing technique; Reference system; Gripper construction
series	journal paper
more	http://www.elsevier.com/locate/autcon
last changed	2003/06/02 09:36

_id	02f7
authors	Liebich, Thomas and Kim, Inhan
year	1995
title	ID'EST: An Integrated Modelling Framework for Management of Architectural Data
source	Sixth International Conference on Computer-Aided Architectural Design Futures [ISBN 9971-62-423-0] Singapore, 24-26 September 1995, pp. 377-387
summary	An Integrated Design Environment, IDE, facilitates cooperation between different disciplines. The paper investigates the data modelling framework, distinguishes between homogeneous and heterogeneous model worlds, discusses the formal mapping mechanisms available to establish a heterogeneous model world, and introduces a way to incorporate CAD systems into IDE A prototype IDE has been developed to prove these methods. The ID'EST prototype comprises its own core data model, different schemas to cope with several design views, and interfaces to incorporate external CAD systems. A prototype architectural data model has been defined, that includes core data models and aspect models for enclosure system and spatial system. Conventional CAD systems can be integrated into ID'EST, if they are able to map data from the aspect models into their own data structure, and vice versa, on a high semantic level. The inherent methods of classifying data in CAD, layers, macros and attached attributes, have been used to retrieve product data from CAD data files. The usability of conventional CAD systems as data instantiation tools for IDE has been proved and a path has been shown, by which existing tools can be integrated into new technology solutions.
keywords	Product Modelling, Formal Mapping Specification, Computer-Aided Design
series	CAAD Futures
email
last changed	2003/05/16 20:58

_id	e092
authors	Streilein, André and Hirschberg, Urs
year	1995
title	Integration of Digital Photogrammetry and CAAD: Constraint-Based Modelling and Semi-Automatic Measurement
source	Sixth International Conference on Computer-Aided Architectural Design Futures [ISBN 9971-62-423-0] Singapore, 24-26 September 1995, pp. 35-47
summary	The integration of state-of-the-art photogrammetric methods with the capabilities of CAAD has great potential for a variety of architectural applications. This paper describes the current status of an ongoing research project which aims to develop an easy to use tool for the photogrammetric generation of accurate, reliable and well structured 3D CAAD models of architectural objects. The system essentially consists of a standard CAAD package to which additional functionality was added and a Digital Photogrammetry Station (DIPS), providing semi-automatic computer measurement. The paper concentrates on two main issues in the design of the system: the data-integration and the CAAD-based 3D feature extraction. The data-integration is achieved using a knowledge-base. On top of an adequate data-transfer between the two systems this knowledge-base enables constraint-based modelling in CAAD and qualitatively controlled measurement in DIPS. In the section about Digital Photogrammetry we describe the 3D feature extraction procedure in detail and point out how the qualitative control can be achieved. A practical example is used to illustrate the performance of the system.
series	CAAD Futures
email
last changed	2003/06/10 12:12

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