CU1703

CASEstudy
Designing Reality
An inspired design, created and developed by architects at ArchiRADAR, won first prize in
Graphisoft's 'Algorithmic Design meets BIM' competition
Architects Michele Calvano, a
Rhino & Grasshopper expert, and
Mario Sacco, an ARCHICAD &
GDL expert, both from ArchiRADAR,
have used an architectural design
workflow, using ARCHICAD, Rhinoceros
and Grasshopper to create responsive
and optimised shading panels on a
free-form high-rise project. The project
won first prize in the 'Algorithmic
Design Meets BIM' competition
sponsored by Graphisoft.
The Software used in the project,
besides Graphisoft’s ARCHICAD,
Rhinoceros and Grasshopper, included
Solibri Model Viewer and Tekla
Structures. "Using ARCHICAD, our first
aim was always to reduce time in
managing projects; using GDL gave us
a lot of flexibility in personalising
schedules and controlling quantities.
Grasshopper gave us an opportunity to
further improve this capability,"
explained Mario Sacco.
The initial, free-form conceptual shape
and geometry of the building was
created using Rhinoceros, which
provided all of the tools they needed to
efficiently create the double-curved
NURBS surfaces that are a feature of
the model, setting graphic controlpoints,
and enabling convenient, realtime
3D editing.
Grasshopper was used to overlay a
mesh surface on the previously
constructed NURBs. As a result, the
complexity of the double-curved surface
was reduced to evenly distributed planar
squad panels grouped in clusters. In
practice, this ensured that most of the
panels have a similar geometry. The
building skin, therefore, is covered by a
series of equal element groups, designed
to increase manufacturing efficiency and
reduce construction costs.
A great advantage of Grasshopper and
Rhino is that all design updates and
changes are handled in real-time, so
that any change in the NURBs in Rhino
causes an instant update of the mesh
surface generated by Grasshopper. This
way, the number and size of the planar
panels could be easily adjusted.
A triangulated grid structure was drawn
in Rhino under the principal surface
using only 3D lines, not solid shapes.
As a consequence, the 3D definition
could be kept very light and was easily
adjustable. The Grasshopper file
generated was a mere 200kb in size.
3D modelling is viewed as 'the ideal
tool' for conceptualising, creating and
visualising a building. The connection
between Grasshopper and ARCHICAD
allows us to take the process further,
making it capable of creating a direct
link between creation and production.
This frees us from following a strictly
linear process, and gives us the
freedom to explore designs in a
dynamic, light multi-model.
Generating the ARCHICAD BIM Lines,
polylines and points, thanks to the AC-
GH Connection, enables them to
become ARCHICAD objects; so the next
step was to convert the previously
generated mesh surfaces and structural
grid elements to parametric ARCHICAD
elements. In this case, the main element
of the building skin was a special, smart,
parametric sun shading screen object
(brise soleil element) written in GDL.
Thanks to the live, bi-directional
Grasshopper-ARCHICAD connection,
such sun shading elements were
created from the mesh surfaces,
enabling the conceptual model to be
transferred into a BIM model.
GENERATIVE DISTRIBUTION AND
POSITIONING OF PARAMETRIC
ARCHICAD SHADING COMPONENTS
This robust, live, two-way connection
was available throughout the entire
design development project phase. Any
changes made in the ARCHICAD
building information model would be
reflected in Rhino, and any changes
initiated in Grasshopper or Rhino would,
similarly, be instantly reflected in the BIM
project as well. As the design evolved,
the GDL elements were able to be
refined with details, and further elements
were able to be added later when
appropriate. The architectural
documentation, including quantity takeoffs
and schedules, were able to be
created easily during any phase of the
design process.
12
March/April 2017