Direct modeling or history-free CAD has grabbed its share of
headlines in the 3-D design world this past year, and Autodesk recently made its splash with a
preview of its new Fusion
technology slated for a future version of Inventor.
Inventor Fusion which Autodesk officials were clear to
position as a technology preview, not a product introduction claims to meld the
power and control of parametric, history-based modeling with the flexibility
and ease of use traditionally offered by direct modelers in a single product,
according to Autodesk officials. The company has opted to unite the two
modeling techniques in one packaged application based on the belief that both
approaches have relevance for different types of design functions, officials
"Parametric and direct modeling both remain relevant," says
Andrew Anagnost, vice president of CAD/CAE for Autodesk's manufacturing
solutions, who drew comparisons between the need for these two approaches and
the co-existence of Autodesk's AutoCAD 2-D software and its Inventor 3-D
offering. "The reason is each one is good at different things."
Parametric or history-based modeling, traditionally the
focus of Inventor and most modern 3-D MCAD programs, uses parent/child
relationships, parameters and features to build intelligence into a model. This kind of tool is typically well suited
for working on complex, highly engineered products and families of products. In
comparison, history-free modelers, sometimes referred to as explicit modeling
tools, create and tweak models through direct interaction with the geometry,
adding parameters and features only when needed. This approach, considered to
be much more flexible, is considered highly effective for companies creating
new products from scratch, along with those that require a relatively quick and
easy way to come up with conceptual designs on an on-going basis.
While both categories of 3-D CAD tools have been around for
decades, direct modeling has grabbed much of the spotlight lately thanks in
part to the entrance of players like SpaceClaim,
a newcomer whose value proposition is based solely on the perceived benefits of
direct modeling. Long-time CAD stalwarts have also planted a stake in direct
modeling ground. Some, like SolidWorks,
have added direct modeling features to their parametric-based tools, while
others have gone further, like PTC,
which acquired CoCreate last year and is offering its direct modeling
package as a complement to its existing Pro/ENGINEER product.
The Autodesk Fusion strategy perhaps most closely mirrors Siemens
PLM Software, which announced Synchronous Technology, used in both
SolidEdge and NX. Like Fusion, Synchronous Technology claims to marry the best
of both direct and history-based CAD tools. It provides direct control of a
model and immediate feedback, an approach Siemens officials say delivers a new
way of interacting with parametric, history-based models without being constrained
by the way a model was constructed.
Given that Fusion is a technology preview, analysts say it's
premature to discern the differences between it and Synchronous Technology.
However, they say interest in direct modeling tools in general is on the rise,
driven mostly by the need of an extended design team to accommodate
multi-source CAD. "Everyone has to be able to compete in a world where their
partners are using lots of different technologies," says Monica Schnitger,
president of Schnitger Corp., a
market analyst firm specializing in engineering. "Most companies can't afford
to have a seat of NX, Pro/E, Solidworks or Inventor sitting around in their
design shops. Direct modelers are pretty good with dealing with multi-source
CAD. Removing the concept of the history tree creates a common ground
Autodesk officials say the Fusion technology will enable
engineers to switch between parametric and direct workflows as it make sense
for a particular task and the software will track the changes in a single
digital model. "The system will take responsibility for how to bring these two
models together," says Kevin Schneider, Autodesk product manager in the
manufacturing solutions division. The alternative approach having two tool sets
that don't share information well has been one of the principal limitations of
previous generations of direct modeling tools, he says.
Useability is another big focus of the Fusion technology.
Autodesk is aiming to replace many of the abstract software concepts that users
have had to learn to be productive in CAD with context-sensitive
point-of-access tools that present only what is needed at the cursor. Instead
of having to hunt around in toolbars, an engineer could hover over an object
and the options that make sense for that particular option will pop up. "The
details present themselves as appropriate, which significantly lowers the
burden and number of tools users need to learn and opens this up to non-CAD
jockeys," Schneider says.
Autodesk officials declined to say exactly when or in
what Inventor release the Fusion technology will surface. The company will,
however, offer a free download of Inventor Fusion Technology Preview on Autodesk Labs later this year.