Cadalyst AEC Tech News #124 (July 15, 2004)15 Jul, 2004 By: Sara Ferris
The BE Conference proper was preceded by daylong research seminars in both architecture and GIS. Hosted by Robert Aish, Bentley's director of research, the Building Research & Technology Seminar covered an assortment of projects. Many of these projects used Bentley's parametric Generative Components technology, which is expected to become available in beta form later this year. First introduced by PTC in its Pro/ENGINEER product, parametric design technology is prevalent in mechanical design software. The research seminar also covered other technologies and design approaches adopted from the mechanical design world.
Generative Components basically provide the parametric modeling capabilities commonly found in mechanical design software, in which constraints govern relationships among geometric features. When the value of a parameter changes, related variables update to reflect the change. This makes it easy to modify designs, experiment with changes to variables, and create families of similar parts. The system ends up doing parts of the design process based on the rules, or parameters.
Bentley's Generative Components comes with a set of predefined relationships, and you can create your own. It also includes a feature history that you can replay. It's also possible to put off defining parameters. The challenge in developing parametric technology for architecture is making systems that people can use, said presenter Rob Woodbury of Simon Fraser University.
Members of blobitecture pioneer Greg Lynn's research and development crew demonstrated the use of Generative Components in the design of an apartment complex. The goal was to create neighborhoods of 50 units each, with escalators providing access to each neighborhood. The project was designed in an Excel spreadsheet, with each cell representing an apartment. A set of 122 trusses were parametrically linked to the escalators, so that when escalators were moved or routed to different floors, the trusses automatically adjusted. More than 20,000 unique components were linked in this project.
Traditionally, architecture involves custom manufacturing-each project is unique. Mechanical design and manufacturing focuses both on standardized production and on mass customization, in which a unique product is quickly assembled from standard modules or components.
Greg Lynn discussed a flatware design in which he developed one primitive on which to base multiple objects. He also showed an example of complex variation in a coffee set made from aircraft titanium.
An architectural example featured modular homes, each a unique configuration of standard fabricated sections. Think hard-boiled eggs sliced up and rearranged.
RAPID PROTOTYPING AND CNC MACHINING
Both of these technologies fit in with the trend toward mass customization because they enable efficient production of small part runs. For one project, custom door handles were machined directly from CAD files. CNC technology is being used in the ongoing work of building Gaudi's Sagrada Familia church.
The ARTHUR Project aims to promote virtual reality as an architectural and urban planning tool, replacing the traditional physical models. Participants use a head-mounted viewing device and a hand-held wand to manipulate the building model. Changes are reflected in the model immediately.
Generative Components also is accessible through a programming interface, and several researchers demonstrated how they linked up design analysis tools. Lisa Matthews used CFD (computational fluid dynamics) software to analyze the stability of cable net and membrane tensile structures under differing airflow conditions.
OTHER NOTES FROM THE CONFERENCE
Returning to mass customization for a moment, AEC Technologies offers ArchSeries, which streamlines the creation of design-to-order products such as kitchen cabinets and bathroom fixtures. The products run on top of MicroStation and integrate with ERP and MRP programs. They automatically generate price quotes and product orders that automatically update when the CAD layout changes.
ArchVision showed its newly released ArchVision Composer ($249), which lets you add RPC (rich photorealistic content) to 2D renderings and photographs. RPC is ArchVision's format for displaying 3D-like images with minimal polygonal geometry to keep file sizes small. The company offers a vast assortment of RPC images and plug-ins needed to insert them into visualization programs. With features like automatic scaling, shadow generation and opacity, and saturation and brightness controls, ArchVision Composer inserts realistic entourage-like people, trees, and cars into renderings. ArchVision Composer runs as a stand-alone application or in conjunction with Adobe Photoshop or Photoshop Elements. Setting up an image in ArchVision Composer is as easy as establishing a horizon line and adjusting the scale of a person to match the background.
Autodesk Technical Evangelist Lynn Allen guides you through a different AutoCAD feature in every edition of her popular "Circles and Lines" tutorial series. For even more AutoCAD how-to, check out Lynn's quick tips in the Cadalyst Video Gallery. Subscribe to Cadalyst's Tips & Tricks Tuesdays free e-newsletter and we'll notify you every time a new video tip is available. All exclusively from Cadalyst!