This example will show how to generate the ThrustDiagram for the Free-form Tile Vault built by the BRG in Zurich, 2010. This example will show how to:
Create a Pattern
from Rhino mesh object
Relax Pattern
using custom force density values (control the curvature of the unsupported boundaries)
Refine crease in the ThrustDiagram
by modifying the ForceDiagram
(to make/accentuate creases)
For this example, a pre-made Rhino mesh will be used to generate the Pattern
. Unzip and open the file below, and do: Create pattern
> From Mesh
.
Before the Pattern
can be relaxed with custom force density values (q), fixed vertices first need to be identified. By using the Corner
and ByContinuousEdges
selection options in Modify Pattern
> Vertices Attributes
, set is_fixed
attributes of the vertices to True
.
Once the fixed vertices have been identified, force densities can be assigned to the edges and the Pattern
can be relaxed. By using the Continuous
selection option in Modify Pattern
> Edges Attributes
, force density values can be defined for continuous chain of unsupported boundary edges. With new force density values assigned, the Pattern
can be relaxed using Modify Pattern
> Relax
. Setting qs and Relax
can be repeated iteratively to achieve the desired curvature of each of the unsupported boundaries. For this example, these q values are used.
Once the Pattern
has been relaxed, anchor vertices can be be defined. In this example, a few more vertices are manually added by using the Manual
selection option in Define Boundary Conditions
> IdentifySupports
. The vertices that are already fixed are automatically defined as anchors.
After a few hundred iterations, horizontal equilibrium is found.
Use TargetHeight
parameter in Vertical Equilibrium to achieve the desired height of the ThrustDiagram
. In this example, TargetHeight
of 4.5 is used.
The creases of this ThrustDiagram
, the edges indicated in the image below that span from anchor to anchor, can be refined by modifying the ForceDiagram
.
By moving the vertices of the ForceDiagram
to elongated the edges corresponding to the creases, the transition at the creases can be smoothened and refined.