C2.5 Increased Force Densities

Change the global force densities to vary the pull the mesh up higher. (by Lotte)

Objective

We will learn how the magnitude of uniform force densities controls the form-found shape.

Procedure

The file is exactly the same as in C2.4 External Loads with the following modifications:

Increase the Force Densities

In the default edge attributes, we will change the force densities 'q' from 1 to 2 for example. This doubles the q uniformly in all edges. With the analogy from C0. Principles, this means that there are twice as many units pulling on the cables.

....
# set default edge attributes
dea = {
    'q': 2.0,             # Force densities of an edge. > NEW!
    '...
}
mesh.update_default_edge_attributes(dea)
...

Always visualise the new geometry in a new layer, so that you can compare the difference.

Comparison to Force Densities 1

It can be observed that the mesh is pulled up again by the higher force densities. This also reflects in the magnitude of reaction forces.

form-found mesh with q=2 vs. q=1 (below) with difference in reaction forces (for q=1 lighter green)

Obvious also in the edge forces are much higher which can be seen also in the comparison of the tube's diameters.

Experiment with higher and lower force densities to get a feeling for it.