Responding to growing concerns regarding energy-efficient facades, this paper describes the structure and process followed in the design of a responsive sun-shading system based on the use of rotating plates with two degrees of freedom. The proposal considers, among others, the definition of variable design parameters, areas of performance evaluation and control, and construction detailing development represented by a first 1:2 unit (module) model. In the process, computational simulation procedures were employed to explore configurational possibilities that would provide high-performance solutions to the light requirements of the particular covered spaces. In developing the system, it was noticed that due to the highly subjective requirements of users in terms of quantity and quality of lighting, a purely Boolean control system would not always be appropriate. Following from that, and taking advantage of the dynamic nature of the system, a further approach of control supported by fuzzy logic was also implemented at the operative state, whose logic is explained. Digital simulations were carried out to assess the performance of the system, and their results demonstrate more even light distribution levels compared to traditional systems.

One of the products of engineering, besides constructed artifacts, is design documentation. To understand how design participants use documentation, designers and typical documentation users were interviewed and protocols were taken of them both creating and using design documentation. The protocols were taken from realistic projects of preliminary design for heating, ventilation, and air conditioning systems (HVAC). The studies of document creation and use revealed three important issues: (1) design participants not only look up design facts; they frequently access documents to obtain information about the rationale for design decisions; (2) the design rationale that they see often is missing from the documents; and (3) design requirements change frequently over a project life cycle so that design documents are often inconsistent and out of date. Recognizing these documentation issues in design practice, a new approach was developed in which documents are no longer static records, but rather interactive design models supporting a case. The feasibility of the approach was demonstrated by constructing a running system and testing it with designers on realistic problems. The costs and benefits of creating and using documentation of design rationale also were analyzed. In particular, the active documents approach was evaluated for a routine, preliminary design in domains where community practice is widely shared and largely standardized. The approach depends on the feasibility of creating a parametric design model for the design domain.

Engineering conceptual design can be defined as that phase of the product development process during which the designer takes a specification for a product to be designed and generates many broad solutions to it. This paper presents a constraint-based approach to supporting interactive conceptual design. The approach is based on an expressive and general technique for modeling: the design knowledge that a designer can exploit during a design project; the life-cycle environment that the final product faces; the design specification that defines the set of requirements the product must satisfy; and the structure of the various schemes that are developed by the designer. A computational reasoning environment based on constraint filtering is proposed as the basis of an interactive design support tool. Using such a tool, human designers can be assisted in interactively developing and evaluating a set of schemes that satisfy the various constraints imposed on the design.

This article contains a description of a constraint solver that determines complete solution spaces. These spaces are defined by sets of constraints in continuous variables. Interactive design is supported through improvements to existing algorithms that have increased system performance. In addition, heuristics for activating the best set of preferred constraints for a design task are presented, and two ways are proposed for interactively exploring design alternatives. IDIOM is an application framework that has successfully tested these algorithms for interactive apartment layout design.