School of Architecture

Layouts, solids, grammar interpreters and fire stations

Robert F. Woodbury et al. — Wed, 23 May 2012 06:33:25 PDT

Abstract: "This paper is presented in three main parts. First, it reports the results of an effort to combine two representations (layouts and solid models) within a single generative framework. Second, it describes fire stations as a building type and reports a phased grammar that embodies information about the type and generates fire station designs likely to be members of the type. Third, it describes a useful way of controlling grammatical generation via interactive decisions on rule application, hierarchical decomposition of designs, and ordering of the conflict set of rule instantiations."

A2 : an architectural agent in a collaborative engineering environment

Ulrich Flemming — Wed, 23 May 2012 06:33:23 PDT

Abstract: "This report describes the functionality of the Architectural Agent (A2) developed by a team at CMU as part of the USACERL- sponsored ACL (Investigation of an Agent Communication Language) project, which addresses communication issues in a distributed computer-supported building design environment. The core functionality of A2 consists of generating schematic layouts of the functional units in a spatial program; this functionality is provided by using SEED-Layout (SL) as a server; SL is a module in the Software Environment to Support the Early Phases in Building Design (SEED) currently under development at the EDRC. A2 is in addition served by the object database UniSQL and AutoCAD, used strictly for display purposes. These diverse components communicate through a message server with each other and a facilitator API provided by another team. The communication protocol and data translations are based on an active object model expressed in the specification language OML developed by the CMU team explicitly for the ACL project. The CMU team also suggests an approach toward conflict management and negotiation for an environment like ACL and describes an OML-based protocol that implements the approach. It offers general conclusions about relevant aspects of the ACL project."

Design space navigation : an annotated bibliography

Sheng-Fen Chien et al. — Wed, 23 May 2012 06:33:22 PDT

Abstract: "SEED, a Software Environment to Support the Early Phases in Building Design, allows designers to explore conceptual alternatives and to iterate over design concepts in their search for a most promising design scheme. But designers using SEED can easily get lost in the multiple design spaces they are able to generate and therefore need intelligent navigation aids. We review in this report the literature related to information navigation in electronic media, including the small subset of sources dealing specifically with design space navigation. The sources listed in the report cover two main subject areas: information navigation and information visualization."

Get with the program : common fallacies in critiques of computer-aided architectural design

Ulrich Flemming et al. — Wed, 23 May 2012 06:33:19 PDT

Abstract: "This paper introduces four common fallacies that are often developed explicitly or implied when approaches toward computer-aided architectural design are criticized from a broader 'philosophical' perspective. It suggests what the author considers more fruitful directions for research in connection with the issues raised. The first two fallacies are very general. The first of these treats design as a monolithic, indivisible process that cannot be decomposed and thus partially supported. The second one insists that computer aids support current practice as it stands and rejects approaches that challenge that practice. The last two fallacies are very specific. The first of these occurs when shape grammars and related mechanisms are criticized for being based on a 'linguistic analogy'. The last one deals with a specific version of appeals to authority that treats Heidegger as the ultimate arbiter in resolving philosophical issues in connection with computer-aided architectural design."

The representation of design problems and maintenance of their structure

Charles M. Eastman — Wed, 23 May 2012 06:33:18 PDT

Computer aided facilities management and design

O╠êmer Akin et al. — Wed, 23 May 2012 06:33:15 PDT

On the representation and generation of loosely-packed arrangements of rectangles

Ulrich Flemming et al. — Fri, 27 Apr 2012 13:01:25 PDT

Abstract: "Several computer programs that enumerate rectangular dissections as solutions to certain layout problems have established a distinct paradigm for dealing with the crucial theoretical issues involved. The present paper suggests an extension of the paradigm to include 'loosely-packed' arrangements of 'rectangles', which are of wider applicability in an architectural context. The paper introduces orthogonal structures to represent arrangements and establishes the conditions of well-formedness for these structures. It presents a grammar to enumerate orthogonal structures and suggests that best use is made of the grammar if it is incorporated into a generative expert system, able to serve as a vehicle to discover, encode and utilize a broad range of constraints and criteria in the generation of layout alternatives."

A generalized Euler-Poincare Equation

Jeff A. Heisserman et al. — Fri, 27 Apr 2012 13:01:23 PDT

Abstract: "The Euler-Poincare╠ü equation, v - e + f = 2(s - g), relates the numbers of topological elements of 2-manifold surfaces. Here v, e, f, s, and g refer to the numbers of vertices, edges, faces, shells (surfaces) and handles. However, the equation does not correctly relate the elements of non-manifold surfaces, and specifically the boundaries of r-sets. We introduce a generalized form of the Euler-Poincare╠üequation v ╠ü- e ╠ü+ f = 2(s ╠ü- g) which relates the number of vertex uses, edge uses, faces, shell uses, and handles of both 2-manifold surfaces and non-manifold surfaces of r-sets.

Behavior modeling in design system development

Robert F. Coyne et al. — Fri, 27 Apr 2012 13:01:21 PDT

Abstract: "We describe the development approach for a software environment to support the early phases in building design called SEED. The combination of capabilities offered by SEED to designers is novel and includes the integrated handling of solution prototypes. We give the reasons for using an object-oriented software engineering approach in the development of the system, which starts with a comprehensive behavioral model of the system from the user's perspective based on actors and use cases. We illustrate results from the first development phase and sketch the next phases. At the time of the CAAD FUTURES '93 conference, we will be able to report our experience in developing a first system prototype and to demonstrate the prototype."

Generative geometric design and boundary solid grammars

Jeff A. Heisserman et al. — Fri, 27 Apr 2012 13:01:20 PDT

Abstract: "This proposal introduces boundary solid grammars, a formalism for generating complex models of rigid solid objects. Solids are represented by their boundary elements, i.e. vertices, edges and facts, with coordinate geometry associated with the vertices. Labels may be associated with any of these elements. Rules match conditions of a solid or collection of solids and may modify them or create additional solids. A boundary solid grammar uses an initial solid and a set of rules to produce a language of solid models. Unary operations are introduced to ensure the validity of the boundary representations.These operations take models that may have self-intersections, interpret the models considering the given geometry and face orientations, and produce valid models. The unary operations allow the use of boolean operations together with Euler, sweeping, tweaking and gluing operations in a unified, valid scheme. The proposed formalism has been implemented. Grammars have been demonstrated that generate simple geometric forms including snowflakes, recursive octahedrons, 'fractal' mountains, and spirals. Queen Anne houses have been characterized in a more extensive grammar."

Architects' reasoning with structures and functions

Omer Akin et al. — Fri, 27 Apr 2012 13:01:18 PDT

Abstract: "While there is a visible increase of publications in the area of design thinking and signs that it is becoming a serious area of research, there is a lack of theoretical approaches that directly address its domain specific characteristics. This study attempts to develop such a theory directed towards design reasoning based on a protocol study and formal notation, among other things. Three domains of reasoning are described: construction, object, and representation. Inference making within and between these domains is described in terms of operations called functions and states called structures in a state-space representation of design. Five types of mapping which are illustrated by the protocol study are described using structures and functions.Both shortcomings and strengths of the proposed theoretical formalisms are discussed. Future work is indicated."

An introduction to structure and structure grammars

Christopher Carlson et al. — Fri, 27 Apr 2012 13:01:17 PDT

Abstract: "Structures represent relationships between parts in configurations. We define the concepts of structure and structure rewriting and show in several examples how these are applied to performing computations on designs and describing design languages."

Hands-on exploration of recursive forms

Christopher Carlson et al. — Fri, 27 Apr 2012 13:01:15 PDT

Abstract: "We describe an extremely simple paradigm that we have used to explore the graphic qualities of recursive forms, forms developed by recursively replicating a motif. Our emphasis is on form exploration, as opposed to form generation, which has been the focus of related work in this area. In spite of the simplicity of the paradigm, an enormous variety of forms and phenomena can be explored with it, including spirals, branching structures, plane symmetries and tilings, 'reptiles', iterated function systems, space-filling curves, 'squigs', meanders, textures, phylotaxis and organic forms.

Design genes

Robert F. Woodbury et al. — Fri, 27 Apr 2012 13:01:13 PDT

Abstract: "This paper proposes an organization for a genetic design system (GDS) that is derived from two sources: (1) the search paradigm in computer-aided design, (2) the structure of natural evolution. Both sources are presented in an abstract form that exposes their mechanism. The components of the search mechanism are related to those of natural evolution, and a system design based on this correspondence is advanced. A critical discussion of the design and a proposed research program are presented."

Variations in solids : a declarative treatment

Robert F. Woodbury et al. — Fri, 27 Apr 2012 13:01:11 PDT

Abstract: "Underlying the notions of variational geometry, design prototypes, features, and representation of assemblies seems to be a common concept of variations. This paper develops the core of a monontonically declarative system for variations on solids. It introduces a set of language constructs that are the basis for ASCEND, an object oriented equation solving language. It presents equations for representing certain spatial relationships between primitive geometric elements. Using plex grammar notation it develops a set of Euler operators that are monotonic in the strict sense required by the ASCEND language.These operators are collectively shown to generate representations for all plane models of 2-manifold objects and to generate only such representations. Finally it presents the core of a system for variations using the ASCEND language to implement both models and the new Euler operators."

Searching for designs : paradigm and progress

Robert F. Woodbury et al. — Fri, 27 Apr 2012 13:01:09 PDT

Abstract: "Most CAD systems operate within a paradigm that makes it impossible for computers to materially assist in design. Yet in the research community, the well-established search paradigm is technically ready for broader application. This paper describes design search using the devices of set theory and grammars. It constructs a model of design spaces as a framework for creating new types of systems, and argues that current professional CAD systems cannot easily adapt the search paradigm. Two approaches to systems that use design search, potentially exhaustive enumeration and spatial grammars are discussed with reference to existing research efforts."

Future roles of knowledge-based systems in the design process

John S. Gero et al. — Fri, 27 Apr 2012 13:01:08 PDT

Geometric design spaces

Robert F. Woodbury et al. — Fri, 27 Apr 2012 13:01:06 PDT

Abstract: "One of the goals of design research is the creation of systems that can be active participants in the design process, in contrast to many current systems that are primarily passive repositories of information. A number of techniques have been employed for these purposes, including constraint satisfaction, synthesis by analogy, prototype refinement and search in a space of designs; the last of these is the subject of this paper. Two formalisms for search in a geometric design space, structure grammars and solid grammars, are introduced."

Efficient user interface in electronic mail systems

Akin et al. — Fri, 27 Apr 2012 13:01:05 PDT

Strategies for interactive design systems

Robert F. Woodbury et al. — Fri, 27 Apr 2012 13:01:03 PDT

An information processing model of human problem solving is used to develop strategies for the design of systems for the interactive generation of designs. Systems of this type are currently not strongly developed anywhere, nor does there exist in the literature a paradigm for their creation. Design is a task which requires different interactive support than that traditionally provided by CAD systems. In this paper those differences are uncovered by comparison of two tasks; one, named definition in this paper, which seems to be well supported by existing systems and the other, the task of design. Use of an information processing model of human problem solving shows that differences between the tasks can be found in every potentially variant portion of the model.The information processing model is again used as a framework to propose mechanisms to support design. These mechanisms act by changing the underlying phenomena upon which the information processing model is built and thus effecting changes, either parametric or structural, in the model. The relative importance of the proposed mechanisms is discussed, leading to the conclusion that the interactive support of search is the most strategic direction for future research.