In
early 1999 IDE entered into a business relationship with specialty
bicycle manufacturer Kestrel-USA. Six months later the award winning
KM40 Airfoil
emerged. Specific to triathelete time trial riders and a one-piece,
airfoiled, carbon fiber construction, the KM40 attracted multiple
design industry awards during 1999 and 2000.
The success of the KM40 program went beyond exceptional design.
Because of IDE's precise CAD development, resulting in highly
accurate compression mold tooling, Kestrel
retained IDE to take on a new and unique challenge in bicycle
frame design - to develop five new modular carbon composite aero
road frames within a development cycle previously unheard of.
This was possible because of IDE's unique combination of design
and engineering skills.
Kestrel's goal was to develop a modular carbon frame that would
be offered in five different sizes. The strategy for the modular
construction was to have common chain and seat stays, which through
a common fluid seam would mate to five different triangles (main
frame sections). The advantages to this strategy are the utilization
of smaller tools, which are easier to heat and cool, resulting
in manufacturing efficiency, a faster development cycle due to
part commonality, and a distinct aesthetic created by the mating
details of the chain and seat stays and main frame sections. The
chain and seat stays are finished with an exposed carbon weave
enhanced by a high polished clear coat. The main frame sections
are finished in a choice of high polished gloss white, kona blue,
or black. The visual effect of the complementary finishes is striking.
Kestrel began initial design concepts with an industrial designer
who had designed several of Kestrel's earlier bike frames. The
design goal was aimed at a reincarnation of the Kestrel 4000 with
enhanced aerodynamic attributes. Once a direction for the look
of the frame was established, he made a hand crafted model of
one of the five frame sizes. IDE then began the refinement and
detail design of the frames based on the selected profile and
the hand crafted model.
Five
New Frames In A Fraction Of The Time
One
of the early technical challenges was conceiving of a way to develop
the 3D NURBS CAD models so they could be modified to create the
four additional frame sizes without starting from scratch for
each size. One of the middle size frames, the Model 550 (55 cm)
was selected to be developed first. This was followed by the Model
520 (52cm), Model 570 (57 cm), Model 480 (48 cm), and finally
the Model 600 (60 cm). IDE began the development of the 570 in
April 2000 and was able to complete the development of all five
frames by November. Kestrel introduced the first two production
tooled models by September of the same year for a remarkably short
8 month development cycle.
IDE developed a modeling strategy to efficiently handle the development
of the five different frame sizes. The fixed mounting points for
each frame size were laid out in ProEngineer with a "relations"
script for all five frames. It was determined that each frame
would have its own developed triangle, which would mount to a
common chain stay and one of two seat stays. Therefore, IDE had
to develop the detail design for five triangles, two seat stays,
and one chain stay. The "relations" data was then imported into
Rhino 3D for the basis of the NURBS development of each bike.
The seat stays and chain stay, which were common elements, were
developed first. The mating seat tubes were unique to each frame
size. The airfoil sections of the triangles were designed "floating"
without seams or joints. Each triangle's tube elements had a different
angular relationship and position; thus a master file was created
in Rhino with the five major tube elements.
The main tube was designed with a high NURBS UV mesh density,
making it possible to remove and add sections of the mesh for
size changes. The mesh had to be dense enough to ensure the bond
joint section remained intact regardless of the tube length. Once
all components were positioned properly, blended joints were placed
between the tube sections and secondary features were added for
cable ports, derailleur, and water bottle mounting.
Using 3D CAD modeling versus hand made wooden molds and plastic
prototypes, IDE detailed five different frames in a fraction of
the typical time traditionally required.
IDE also developed the product branding for the Talon. Just as
with the frame design, the graphics were meant to update the design
language of the original Kestrel 4000 with unique Talon imagery.
The bold color palette of the 4000 was applied to the new graphics
and the juxtaposition of the various colors was done in such a
way that the same decals could be used effectively on all frame
colors.
