Bridging BIM:
Digital Prototyping for greater predictability and control in building design and delivery
Robert Cohee,
Posted
12/01/2009
Increasingly
ambitious building designs, the growing technical complexity of
modern building envelopes, requirements for more sustainable design
and mounting economic pressures are all leading the building
industry to seek more efficient processes that improve
predictability and control throughout the building design process.
The integrated design and fabrication of building components is
becoming more prevalent in architecture, thus challenging ideas as
to what is possible and how project information is created and
consumed. The building industry must now begin to reevaluate its
established methods in order to become a more predictable,
sustainable and environmentally responsible business.
Building information modeling is enabling processes-such as
Integrated Project Delivery-to address these emerging trends. IPD
helps teams meet increasing client demands by easing and
integrating the collaborative efforts of owners, architects,
engineers, construction managers, fabricators and end operators at
the earliest possible stage of any project. To fully realize the
benefits of IPD, project stakeholders need to address the digital
exchange of information and the potential it has to change the
nature of how design data is communicated.
Exchanging information between architects, engineers and
construction disciplines is hardly revolutionary, however, the
mechanism in which they exchange information is. In most cases
design intent-no matter its scale or complexity-is reduced to its
simplest form and knowledge is usually lost in the translation.
Drafting, modeling, paper based and digital exchange standards have
evolved with the intention of improving communication between
author and recipient. The author understands the design to the
extent that he or she is required to fulfill their part of the
design. The recipient then interprets the author's representation
of the design and is at that time informed enough to make the
required design, purchasing, assembly, construction or fabrication
decision. And the process repeats itself-interpret intent, design
decision is made, capture intent, standardize translation mechanism
and exchange with recipient.
BIM and Digital Prototyping
BIM is an integrated process built on coordinated, reliable
information about a project from design through construction and
into operations. By adopting BIM, architects, engineers,
contractors and owners can easily create and share consistent,
digital design information and documentation; use that information
to accurately visualize, simulate and analyze performance,
appearance and cost; and reliably deliver the project faster, more
economically and with reduced environmental impact.
While the benefits of BIM are becoming increasingly recognized in
the AEC realm, the increasing prevalence of offsite building
component fabrication is driving the need for applying advanced
processes, like Digital Prototyping, that have traditionally served
the manufacturing industry. A term commonly used among fabricators
and building product manufacturers; Digital Prototyping is the
basic concept of testing a virtual, yet complete product before
it's built. The process lets you create, optimize and validate an
accurate 3-D simulation of product designs.
Through Digital
Prototyping and BIM, project teams can experience a project
digitally before it's built, simulate performance and
constructability, and communicate and interpret design intent to
more cost effectively produce design-intensive building components.
Both BIM and Digital Prototyping share a common objective to
provide a data rich model. These information rich models enable
building process participants to extract the information they need
based on their functional requirements.
When strategically applied, BIM and Digital Prototyping complement
each other to the extent that the information required for creating
and relaying architectural intent as well as manufacturing,
construction and assembly levels of detail occur as a matter of
consequence, and not as a reinterpretation of intent at each phase
of construction. An architect requires information to be created
and communicated at different levels of detail than a fabricator.
What is distinguishable is that the levels of detail are different,
meaning not more or less detail but significantly different in
their standards, representation of objects and granularity. The
level of detail required to effectively communicate intent is
determined simply by the task required to achieve it.
Today, information is re-modeled or re-drawn as it is distributed
throughout the process at an astonishing rate. Beyond the impact of
both time and budget is the loss of knowledge captured in the
original model, which often leads to an inability to retain and
clearly communicate design intent. In addition, models of
interconnecting building components are rarely combined digitally
in order to identify and resolve constructability and performance
issues between trades before the building has begun
construction.
Information as a Matter of Consequence
The illustration below is a simple example of how design is
communicated at different levels of detail. What is relevant and
important to the architect is different than the details required
to fabricate the same building component.
A digital design-to-fabrication workflow enables architects to
create the architectural level of detail using the same model from
which a fabricator is then able to create the manufacturing models
and engineering levels of detail. Therefore the information
required to perform any specific process in the workflow can be
produced without re-modeling, or re-drawing an element of a
building that has already informed the BIM model. The required
information is created as a matter of consequence and not as a
reinterpretation of intent.
Continually informing a digital BIM process through a
design-to-fabrication workflow is not married to, nor should it be
associated with, a single monolithic technology that can be all
things to all people. Today, technology solutions exist that focus
their efforts around one application as a focal point for an entire
project. Participants in the building design and construction
process require focused and targeted toolsets to assist in the
specific tasks related to the trade or activity required at that
time. The monolithic approach does not provide the ability for the
end user to choose the appropriate toolset for the task at
hand.
Resulting Benefits
The digital design-to-fabrication workflow is not something that
users can buy off of the shelf or ask for directly; nor is it
something that is done explicitly. The benefit, however, is that
constructability is improved, and aesthetics, fit and cost issues
are realized earlier in the design process. A digital
design-to-fabrication workflow opens up opportunities for improved
collaboration among architects, fabricators and builders; using
coordinated intelligent data within a fully informed building
information model.
Robert Cohee is an industry solution evangelist for
Autodesk, San Rafael, Calif. Find more information at
www.autodesk.com.
www.autodesk.com